(* Copyright (c) 2008, Adam Chlipala
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - The names of contributors may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *)

(* Pretty-printing C jr. *)

structure CjrPrint :> CJR_PRINT = struct

open Print.PD
open Print

open Cjr

val dummyt = (TRecord 0, ErrorMsg.dummySpan)

structure E = CjrEnv
structure EM = ErrorMsg

structure SK = struct
type ord_key = string
val compare = String.compare
end

structure SS = BinarySetFn(SK)
structure SM = BinaryMapFn(SK)
structure IS = IntBinarySet

structure CM = BinaryMapFn(struct
                           type ord_key = char
                           val compare = Char.compare
                           end)

val debug = ref false

val dummyTyp = (TDatatype (Enum, 0, ref []), ErrorMsg.dummySpan)

val ident = String.translate (fn #"'" => "PRIME"
                               | ch => str ch)

val p_ident = string o ident

fun isUnboxable (t : typ) =
    case #1 t of
        TDatatype (Default, _, _) => true
      | TFfi ("Basis", "string") => true
      | _ => false

fun p_typ' par env (t, loc) =
    case t of
        TFun (t1, t2) => (EM.errorAt loc "Function type remains";
                          string "<FUNCTION>")
      | TRecord i => box [string "struct",
                          space,
                          string "__uws_",
                          string (Int.toString i)]
      | TDatatype (Enum, n, _) =>
        (box [string "enum",
              space,
              string ("__uwe_" ^ #1 (E.lookupDatatype env n) ^ "_" ^ Int.toString n)]
         handle CjrEnv.UnboundNamed _ => string ("__uwd_UNBOUND__" ^ Int.toString n))
      | TDatatype (Option, n, xncs) =>
        (case ListUtil.search #3 (!xncs) of
             NONE => raise Fail "CjrPrint: TDatatype marked Option has no constructor with an argument"
           | SOME t =>
             case #1 t of
                 TDatatype _ => p_typ' par env t
               | TFfi ("Basis", "string") => p_typ' par env t
               | _ => box [p_typ' par env t,
                           string "*"])
      | TDatatype (Default, n, _) =>
        (box [string "struct",
              space,
              string ("__uwd_" ^ #1 (E.lookupDatatype env n) ^ "_" ^ Int.toString n ^ "*")]
         handle CjrEnv.UnboundNamed _ => string ("__uwd_UNBOUND__" ^ Int.toString n))
      | TFfi (m, x) => box [string "uw_", p_ident m, string "_", p_ident x]
      | TOption t =>
        if isUnboxable t then
            p_typ' par env t
        else
            box [p_typ' par env t,
                 string "*"]

and p_typ env = p_typ' false env

fun p_rel env n = string ("__uwr_" ^ ident (#1 (E.lookupERel env n)) ^ "_" ^ Int.toString (E.countERels env - n - 1))
    handle CjrEnv.UnboundRel _ => string ("__uwr_UNBOUND_" ^ Int.toString (E.countERels env - n - 1))

fun p_enamed env n =
    string ("__uwn_" ^ ident (#1 (E.lookupENamed env n)) ^ "_" ^ Int.toString n)
    handle CjrEnv.UnboundNamed _ => string ("__uwn_UNBOUND_" ^ Int.toString n)

fun p_con_named env n =
    string ("__uwc_" ^ ident (#1 (E.lookupConstructor env n)) ^ "_" ^ Int.toString n)
    handle CjrEnv.UnboundNamed _ => string ("__uwc_UNBOUND_" ^ Int.toString n)

fun p_pat_preamble env (p, _) =
    case p of
        PWild => (box [],
                  env)
      | PVar (x, t) => (box [p_typ env t,
                             space,
                             string "__uwr_",
                             p_ident x,
                             string "_",
                             string (Int.toString (E.countERels env)),
                             string ";",
                             newline],
                        E.pushERel env x t)
      | PPrim _ => (box [], env)
      | PCon (_, _, NONE) => (box [], env)
      | PCon (_, _, SOME p) => p_pat_preamble env p
      | PRecord xps =>
        foldl (fn ((_, p, _), (pp, env)) =>
                  let
                      val (pp', env) = p_pat_preamble env p
                  in
                      (box [pp', pp], env)
                  end) (box [], env) xps
      | PNone _ => (box [], env)
      | PSome (_, p) => p_pat_preamble env p

fun p_patCon env pc =
    case pc of
        PConVar n => p_con_named env n
      | PConFfi {mod = m, con, ...} => string ("uw_" ^ ident m ^ "_" ^ ident con)

fun p_pat (env, exit, depth) (p, _) =
    case p of
        PWild =>
        (box [], env)
      | PVar (x, t) =>
        (box [string "__uwr_",
              p_ident x,
              string "_",
              string (Int.toString (E.countERels env)),
              space,
              string "=",
              space,
              string "disc",
              string (Int.toString depth),
              string ";"],
         E.pushERel env x t)
      | PPrim (Prim.Int n) =>
        (box [string "if",
              space,
              string "(disc",
              string (Int.toString depth),
              space,
              string "!=",
              space,
              Prim.p_t_GCC (Prim.Int n),
              string ")",
              space,
              exit],
         env)
      | PPrim (Prim.String s) =>
        (box [string "if",
              space,
              string "(strcmp(disc",
              string (Int.toString depth),
              string ",",
              space,
              Prim.p_t_GCC (Prim.String s),
              string "))",
              space,
              exit],
         env)
      | PPrim _ => raise Fail "CjrPrint: Disallowed PPrim primitive"

      | PCon (dk, pc, po) =>
        let
            val (p, env) =
                case po of
                    NONE => (box [], env)
                  | SOME p =>
                    let
                        val (p, env) = p_pat (env, exit, depth + 1) p

                        val (x, to) = case pc of
                                          PConVar n =>
                                          let
                                              val (x, to, _) = E.lookupConstructor env n
                                          in
                                              ("uw_" ^ ident x, to)
                                          end
                                        | PConFfi {mod = m, con, arg, ...} =>
                                          ("uw_" ^ ident m ^ "_" ^ ident con, arg)

                        val t = case to of
                                    NONE => raise Fail "CjrPrint: Constructor mismatch"
                                  | SOME t => t
                    in
                        (box [string "{",
                              newline,
                              p_typ env t,
                              space,
                              string "disc",
                              string (Int.toString (depth + 1)),
                              space,
                              string "=",
                              space,
                              case dk of
                                  Enum => raise Fail "CjrPrint: Looking at argument of no-argument constructor"
                                | Default => box [string "disc",
                                                  string (Int.toString depth),
                                                  string "->data.",
                                                  string x]
                                | Option =>
                                  if isUnboxable t then
                                      box [string "disc",
                                           string (Int.toString depth)]
                                  else
                                      box [string "*disc",
                                           string (Int.toString depth)],
                              string ";",
                              newline,
                              p,
                              newline,
                              string "}"],
                         env)
                    end
        in
            (box [string "if",
                  space,
                  string "(disc",
                  string (Int.toString depth),
                  case (dk, po) of
                      (Enum, _) => box [space,
                                        string "!=",
                                        space,
                                        p_patCon env pc]
                    | (Default, _) => box [string "->tag",
                                           space,
                                           string "!=",
                                           space,
                                           p_patCon env pc]
                    | (Option, NONE) => box [space,
                                             string "!=",
                                             space,
                                             string "NULL"]
                    | (Option, SOME _) => box [space,
                                               string "==",
                                               space,
                                               string "NULL"],
                  string ")",
                  space,
                  exit,
                  newline,
                  p],
             env)
        end

      | PRecord xps =>
        let
            val (xps, env) =
                ListUtil.foldlMap (fn ((x, p, t), env) =>
                                      let
                                          val (p, env) = p_pat (env, exit, depth + 1) p

                                          val p = box [string "{",
                                                       newline,
                                                       p_typ env t,
                                                       space,
                                                       string "disc",
                                                       string (Int.toString (depth + 1)),
                                                       space,
                                                       string "=",
                                                       space,
                                                       string "disc",
                                                       string (Int.toString depth),
                                                       string ".__uwf_",
                                                       p_ident x,
                                                       string ";",
                                                       newline,
                                                       p,
                                                       newline,
                                                       string "}"]
                                      in
                                          (p, env)
                                      end) env xps
        in
            (p_list_sep newline (fn x => x) xps,
             env)
        end

      | PNone t =>
        (box [string "if",
              space,
              string "(disc",
              string (Int.toString depth),
              space,
              string "!=",
              space,
              string "NULL)",
              space,
              exit,
              newline],
         env)

      | PSome (t, p) =>
        let
            val (p, env) =
                let
                    val (p, env) = p_pat (env, exit, depth + 1) p
                in
                    (box [string "{",
                          newline,
                          p_typ env t,
                          space,
                          string "disc",
                          string (Int.toString (depth + 1)),
                          space,
                          string "=",
                          space,
                          if isUnboxable t then
                              box [string "disc",
                                   string (Int.toString depth)]
                          else
                              box [string "*disc",
                                   string (Int.toString depth)],
                          string ";",
                          newline,
                          p,
                          newline,
                          string "}"],
                     env)
                end
        in
            (box [string "if",
                  space,
                  string "(disc",
                  string (Int.toString depth),
                  space,
                  string "==",
                  space,
                  string "NULL)",
                  space,
                  exit,
                  newline,
                  p],
             env)
        end

local
    val count = ref 0
in
fun newGoto () =
    let
        val r = !count
    in
        count := r + 1;
        string ("L" ^ Int.toString r)
    end
end

fun patConInfo env pc =
    case pc of
        PConVar n =>
        let
            val (x, _, dn) = E.lookupConstructor env n
            val (dx, _) = E.lookupDatatype env dn
        in
            ("__uwd_" ^ ident dx ^ "_" ^ Int.toString dn,
             "__uwc_" ^ ident x ^ "_" ^ Int.toString n,
             "uw_" ^ ident x)
        end
      | PConFfi {mod = m, datatyp, con, ...} =>
        ("uw_" ^ ident m ^ "_" ^ ident datatyp,
         "uw_" ^ ident m ^ "_" ^ ident con,
         "uw_" ^ ident con)

fun p_unsql wontLeakStrings env (tAll as (t, loc)) e =
    case t of
        TFfi ("Basis", "int") => box [string "uw_Basis_stringToInt_error(ctx, ", e, string ")"]
      | TFfi ("Basis", "float") => box [string "uw_Basis_stringToFloat_error(ctx, ", e, string ")"]
      | TFfi ("Basis", "string") =>
        if wontLeakStrings then
            e
        else
            box [string "uw_Basis_strdup(ctx, ", e, string ")"]
      | TFfi ("Basis", "bool") => box [string "uw_Basis_stringToBool_error(ctx, ", e, string ")"]
      | TFfi ("Basis", "time") => box [string "uw_Basis_stringToTime_error(ctx, ", e, string ")"]

      | _ => (ErrorMsg.errorAt loc "Don't know how to unmarshal type from SQL";
              Print.eprefaces' [("Type", p_typ env tAll)];
              string "ERROR")

fun p_getcol wontLeakStrings env (tAll as (t, loc)) i =
    case t of
        TOption t =>
        box [string "(PQgetisnull (res, i, ",
             string (Int.toString i),
             string ") ? NULL : ",
             case t of
                 (TFfi ("Basis", "string"), _) => p_getcol wontLeakStrings env t i
               | _ => box [string "({",
                           newline,
                           p_typ env t,
                           space,
                           string "*tmp = uw_malloc(ctx, sizeof(",
                           p_typ env t,
                           string "));",
                           newline,
                           string "*tmp = ",
                           p_getcol wontLeakStrings env t i,
                           string ";",
                           newline,
                           string "tmp;",
                           newline,
                           string "})"],
             string ")"]
             
      | _ =>
        p_unsql wontLeakStrings env tAll
                (box [string "PQgetvalue(res, i, ",
                      string (Int.toString i),
                      string ")"])

datatype sql_type =
         Int
       | Float
       | String
       | Bool
       | Time
       | Nullable of sql_type

fun p_sql_type' t =
    case t of
        Int => "uw_Basis_int"
      | Float => "uw_Basis_float"
      | String => "uw_Basis_string"
      | Bool => "uw_Basis_bool"
      | Time => "uw_Basis_time"
      | Nullable String => "uw_Basis_string"
      | Nullable t => p_sql_type' t ^ "*"

fun p_sql_type t = string (p_sql_type' t)

fun getPargs (e, _) =
    case e of
        EPrim (Prim.String _) => []
      | EFfiApp ("Basis", "strcat", [e1, e2]) => getPargs e1 @ getPargs e2

      | EFfiApp ("Basis", "sqlifyInt", [e]) => [(e, Int)]
      | EFfiApp ("Basis", "sqlifyFloat", [e]) => [(e, Float)]
      | EFfiApp ("Basis", "sqlifyString", [e]) => [(e, String)]
      | EFfiApp ("Basis", "sqlifyBool", [e]) => [(e, Bool)]
      | EFfiApp ("Basis", "sqlifyTime", [e]) => [(e, Time)]

      | EFfiApp ("Basis", "sqlifyIntN", [e]) => [(e, Nullable Int)]
      | EFfiApp ("Basis", "sqlifyFloatN", [e]) => [(e, Nullable Float)]
      | EFfiApp ("Basis", "sqlifyStringN", [e]) => [(e, Nullable String)]
      | EFfiApp ("Basis", "sqlifyBoolN", [e]) => [(e, Nullable Bool)]
      | EFfiApp ("Basis", "sqlifyTimeN", [e]) => [(e, Nullable Time)]

      | ECase (e,
               [((PCon (_, PConFfi {mod = "Basis", con = "True", ...}, _), _),
                 (EPrim (Prim.String "TRUE"), _)),
                ((PCon (_, PConFfi {mod = "Basis", con = "False", ...}, _), _),
                 (EPrim (Prim.String "FALSE"), _))],
               _) => [(e, Bool)]

      | _ => raise Fail "CjrPrint: getPargs"

fun p_ensql t e =
    case t of
        Int => box [string "uw_Basis_attrifyInt(ctx, ", e, string ")"]
      | Float => box [string "uw_Basis_attrifyFloat(ctx, ", e, string ")"]
      | String => e
      | Bool => box [string "(", e, string " ? \"TRUE\" : \"FALSE\")"]
      | Time => box [string "uw_Basis_sqlifyTime(ctx, ", e, string ")"]
      | Nullable String => e
      | Nullable t => box [string "(",
                           e,
                           string " == NULL ? NULL : ",
                           p_ensql t (box [string "*", e]),
                           string ")"]

fun notLeaky env allowHeapAllocated =
    let
        fun nl (t, _) =
            case t of
                TFun _ => false
              | TRecord n =>
                let
                    val xts = E.lookupStruct env n
                in
                    List.all (fn (_, t) => nl t) xts
                end
              | TDatatype (dk, _, ref cons) =>
                (allowHeapAllocated orelse dk = Enum)
                andalso List.all (fn (_, _, to) => case to of
                                                       NONE => true
                                                     | SOME t => nl t) cons
              | TFfi ("Basis", "string") => false
              | TFfi _ => true
              | TOption t => allowHeapAllocated andalso nl t
    in
        nl
    end

fun capitalize s =
    if s = "" then
        ""
    else
        str (Char.toUpper (String.sub (s, 0))) ^ String.extract (s, 1, NONE)

fun unurlify env (t, loc) =
    let
        fun unurlify' rf t =
            case t of
                TFfi ("Basis", "unit") => string ("uw_unit_v")
              | TFfi (m, t) => string ("uw_" ^ ident m ^ "_unurlify" ^ capitalize t ^ "(ctx, &request)")

              | TRecord 0 => string "uw_unit_v"
              | TRecord i =>
                let
                    val xts = E.lookupStruct env i
                in
                    box [string "({",
                         newline,
                         box (map (fn (x, t) =>
                                      box [p_typ env t,
                                           space,
                                           string "uwr_",
                                           string x,
                                           space,
                                           string "=",
                                           space,
                                           unurlify' rf (#1 t),
                                           string ";",
                                           newline]) xts),
                         string "struct",
                         space,
                         string "__uws_",
                         string (Int.toString i),
                         space,
                         string "tmp",
                         space,
                         string "=",
                         space,
                         string "{",
                         space,
                         p_list_sep (box [string ",", space]) (fn (x, _) => box [string "uwr_",
                                                                                 string x]) xts,
                         space,
                         string "};",
                         newline,
                         string "tmp;",
                         newline,
                         string "})"]
                end

              | TDatatype (Enum, i, _) =>
                let
                    val (x, xncs) = E.lookupDatatype env i

                    fun doEm xncs =
                        case xncs of
                            [] => string ("(uw_error(ctx, FATAL, \"Error unurlifying datatype "
                                          ^ x ^ "\"), (enum __uwe_"
                                          ^ x ^ "_" ^ Int.toString i ^ ")0)")
                          | (x', n, to) :: rest =>
                            box [string "((!strncmp(request, \"",
                                 string x',
                                 string "\", ",
                                 string (Int.toString (size x')),
                                 string ") && (request[",
                                 string (Int.toString (size x')),
                                 string "] == 0 || request[",
                                 string (Int.toString (size x')),
                                 string ("] == '/')) ? __uwc_" ^ ident x' ^ "_" ^ Int.toString n),
                                 space,
                                 string ":",
                                 space,
                                 doEm rest,
                                 string ")"]
                in
                    doEm xncs
                end

              | TDatatype (Option, i, xncs) =>
                if IS.member (rf, i) then
                    box [string "unurlify_",
                         string (Int.toString i),
                         string "()"]
                else
                    let
                        val (x, _) = E.lookupDatatype env i

                        val (no_arg, has_arg, t) =
                            case !xncs of
                                [(no_arg, _, NONE), (has_arg, _, SOME t)] =>
                                (no_arg, has_arg, t)
                              | [(has_arg, _, SOME t), (no_arg, _, NONE)] =>
                                (no_arg, has_arg, t)
                              | _ => raise Fail "CjrPrint: unfooify misclassified Option datatype"

                        val rf = IS.add (rf, i)
                    in
                        box [string "({",
                             space,
                             p_typ env t,
                             space,
                             string "*unurlify_",
                             string (Int.toString i),
                             string "(void) {",
                             newline,
                             box [string "return (request[0] == '/' ? ++request : request,",
                                  newline,
                                  string "((!strncmp(request, \"",
                                  string no_arg,
                                  string "\", ",
                                  string (Int.toString (size no_arg)),
                                  string ") && (request[",
                                  string (Int.toString (size no_arg)),
                                  string "] == 0 || request[",
                                  string (Int.toString (size no_arg)),
                                  string "] == '/')) ? (request",
                                  space,
                                  string "+=",
                                  space,
                                  string (Int.toString (size no_arg)),
                                  string ", NULL) : ((!strncmp(request, \"",
                                  string has_arg,
                                  string "\", ",
                                  string (Int.toString (size has_arg)),
                                  string ") && (request[",
                                  string (Int.toString (size has_arg)),
                                  string "] == 0 || request[",
                                  string (Int.toString (size has_arg)),
                                  string "] == '/')) ? (request",
                                  space,
                                  string "+=",
                                  space,
                                  string (Int.toString (size has_arg)),
                                  string ", (request[0] == '/' ? ++request : NULL), ",
                                  newline,
                                  
                                  if isUnboxable  t then
                                      unurlify' rf (#1 t)
                                  else
                                      box [string "({",
                                           newline,
                                           p_typ env t,
                                           space,
                                           string "*tmp",
                                           space,
                                           string "=",
                                           space,
                                           string "uw_malloc(ctx, sizeof(",
                                           p_typ env t,
                                           string "));",
                                           newline,
                                           string "*tmp",
                                           space,
                                           string "=",
                                           space,
                                           unurlify' rf (#1 t),
                                           string ";",
                                           newline,
                                           string "tmp;",
                                           newline,
                                           string "})"],
                                  string ")",
                                  newline,
                                  string ":",
                                  space,
                                  string ("(uw_error(ctx, FATAL, \"Error unurlifying datatype " ^ x
                                          ^ "\"), NULL))));"),
                                  newline],
                             string "}",
                             newline,
                             newline,

                             string "unurlify_",
                             string (Int.toString i),
                             string "();",
                             newline,
                             string "})"]
                    end

              | TDatatype (Default, i, _) =>
                if IS.member (rf, i) then
                    box [string "unurlify_",
                         string (Int.toString i),
                         string "()"]
                else
                    let
                        val (x, xncs) = E.lookupDatatype env i

                        val rf = IS.add (rf, i)

                        fun doEm xncs =
                            case xncs of
                                [] => string ("(uw_error(ctx, FATAL, \"Error unurlifying datatype "
                                              ^ x ^ "\"), NULL)")
                              | (x', n, to) :: rest =>
                                box [string "((!strncmp(request, \"",
                                     string x',
                                     string "\", ",
                                     string (Int.toString (size x')),
                                     string ") && (request[",
                                     string (Int.toString (size x')),
                                     string "] == 0 || request[",
                                     string (Int.toString (size x')),
                                     string "] == '/')) ? ({",
                                     newline,
                                     string "struct",
                                     space,
                                     string ("__uwd_" ^ ident x ^ "_" ^ Int.toString i),
                                     space,
                                     string "*tmp = uw_malloc(ctx, sizeof(struct __uwd_",
                                     string x,
                                     string "_",
                                     string (Int.toString i),
                                     string "));",
                                     newline,
                                     string "tmp->tag",
                                     space,
                                     string "=",
                                     space,
                                     string ("__uwc_" ^ ident x' ^ "_" ^ Int.toString n),
                                     string ";",
                                     newline,
                                     string "request",
                                     space,
                                     string "+=",
                                     space,
                                     string (Int.toString (size x')),
                                     string ";",
                                     newline,
                                     string "if (request[0] == '/') ++request;",
                                     newline,
                                     case to of
                                         NONE => box []
                                       | SOME (t, _) => box [string "tmp->data.uw_",
                                                             p_ident x',
                                                             space,
                                                             string "=",
                                                             space,
                                                             unurlify' rf t,
                                                             string ";",
                                                             newline],
                                     string "tmp;",
                                     newline,
                                     string "})",
                                     space,
                                     string ":",
                                     space,
                                     doEm rest,
                                     string ")"]
                    in
                        box [string "({",
                             space,
                             p_typ env (t, ErrorMsg.dummySpan),
                             space,
                             string "unurlify_",
                             string (Int.toString i),
                             string "(void) {",
                             newline,
                             box [string "return",
                                  space,
                                  doEm xncs,
                                  string ";",
                                  newline],
                             string "}",
                             newline,
                             newline,

                             string "unurlify_",
                             string (Int.toString i),
                             string "();",
                             newline,
                             string "})"]
                    end

              | TOption t =>
                box [string "(request[0] == '/' ? ++request : request, ",
                     string "((!strncmp(request, \"None\", 4) ",
                     string "&& (request[4] == 0 || request[4] == '/')) ",
                     string "? (request += 4, NULL) ",
                     string ": ((!strncmp(request, \"Some\", 4) ",
                     string "&& request[4] == '/') ",
                     string "? (request += 5, ",
                     if isUnboxable  t then
                         unurlify' rf (#1 t)
                     else
                         box [string "({",
                              newline,
                              p_typ env t,
                              space,
                              string "*tmp",
                              space,
                              string "=",
                              space,
                              string "uw_malloc(ctx, sizeof(",
                              p_typ env t,
                              string "));",
                              newline,
                              string "*tmp",
                              space,
                              string "=",
                              space,
                              unurlify' rf (#1 t),
                              string ";",
                              newline,
                              string "tmp;",
                              newline,
                              string "})"],
                     string ") :",
                     space,
                     string "(uw_error(ctx, FATAL, \"Error unurlifying option type\"), NULL))))"]

              | _ => (ErrorMsg.errorAt loc "Unable to choose a URL decoding function";
                      space)
    in
        unurlify' IS.empty t
    end

fun p_exp' par env (e, loc) =
    case e of
        EPrim p => Prim.p_t_GCC p
      | ERel n => p_rel env n
      | ENamed n => p_enamed env n
      | ECon (Enum, pc, _) => p_patCon env pc
      | ECon (Option, pc, NONE) => string "NULL"
      | ECon (Option, pc, SOME e) =>
        let
            val to = case pc of
                         PConVar n => #2 (E.lookupConstructor env n)
                       | PConFfi {arg, ...} => arg

            val t = case to of
                        NONE => raise Fail "CjrPrint: ECon argument status mismatch"
                      | SOME t => t
        in
            if isUnboxable t then
                p_exp' par env e
            else
                box [string "({",
                     newline,
                     p_typ env t,
                     space,
                     string "*tmp",
                     space,
                     string "=",
                     space,
                     string "uw_malloc(ctx, sizeof(",
                     p_typ env t,
                     string "));",
                     newline,
                     string "*tmp",
                     space,
                     string "=",
                     p_exp' par env e,
                     string ";",
                     newline,
                     string "tmp;",
                     newline,
                     string "})"]
        end
      | ECon (Default, pc, eo) =>
        let
            val (xd, xc, xn) = patConInfo env pc
        in
            box [string "({",
                 newline,
                 string "struct",
                 space,
                 string xd,
                 space,
                 string "*tmp",
                 space,
                 string "=",
                 space,
                 string "uw_malloc(ctx, sizeof(struct ",
                 string xd,
                 string "));",
                 newline,
                 string "tmp->tag",
                 space,
                 string "=",
                 space,
                 string xc,
                 string ";",
                 newline,
                 case eo of
                     NONE => box []
                   | SOME e => box [string "tmp->data.",
                                    string xn,
                                    space,
                                    string "=",
                                    space,
                                    p_exp env e,
                                    string ";",
                                    newline],
                 string "tmp;",
                 newline,
                 string "})"]          
        end
      | ENone _ => string "NULL"
      | ESome (t, e) =>
        if isUnboxable t then
            p_exp' par env e
        else
            box [string "({",
                 newline,
                 p_typ env t,
                 space,
                 string "*tmp",
                 space,
                 string "=",
                 space,
                 string "uw_malloc(ctx, sizeof(",
                 p_typ env t,
                 string "));",
                 newline,
                 string "*tmp",
                 space,
                 string "=",
                 p_exp' par env e,
                 string ";",
                 newline,
                 string "tmp;",
                 newline,
                 string "})"]

      | EFfi (m, x) => box [string "uw_", p_ident m, string "_", p_ident x]
      | EError (e, t) =>
        box [string "({",
             newline,
             p_typ env t,
             space,
             string "tmp;",
             newline,
             string "uw_error(ctx, FATAL, \"",
             string (ErrorMsg.spanToString loc),
             string ": %s\", ",
             p_exp env e,
             string ");",
             newline,
             string "tmp;",
             newline,
             string "})"]
      | EApp ((EError (e, (TFun (_, ran), _)), loc), _) =>
        p_exp env (EError (e, ran), loc)

      | EFfiApp (m, x, es) => box [string "uw_",
                                   p_ident m,
                                   string "_",
                                   p_ident x,
                                   string "(ctx, ",
                                   p_list (p_exp env) es,
                                   string ")"]
      | EApp (f, args) =>
        parenIf par (box [p_exp' true env f,
                          string "(ctx,",
                          space,
                          p_list_sep (box [string ",", space]) (p_exp env) args,
                          string ")"])

      | EUnop (s, e1) =>
        parenIf par (box [string s,
                          space,
                          p_exp' true env e1])

      | EBinop (s, e1, e2) =>
        if Char.isAlpha (String.sub (s, size s - 1)) then
            box [string s,
                 string "(",
                 p_exp env e1,
                 string ",",
                 space,
                 p_exp env e2,
                 string ")"]
        else
            parenIf par (box [p_exp' true env e1,
                              space,
                              string s,
                              space,
                              p_exp' true env e2])

      | ERecord (i, xes) => box [string "({",
                                 space,
                                 string "struct",
                                 space,
                                 string ("__uws_" ^ Int.toString i),
                                 space,
                                 string "tmp",
                                 space,
                                 string "=",
                                 space,
                                 string "{",
                                 p_list (fn (_, e) =>
                                            p_exp env e) xes,
                                 string "};",
                                 space,
                                 string "tmp;",
                                 space,
                                 string "})" ]
      | EField (e, x) =>
        box [p_exp' true env e,
             string ".__uwf_",
             p_ident x]

      | ECase (e, pes, {disc, result}) =>
        let
            val final = newGoto ()

            val body = foldl (fn ((p, e), body) =>
                               let
                                   val exit = newGoto ()
                                   val (pr, _) = p_pat_preamble env p
                                   val (p, env) = p_pat (env,
                                                         box [string "goto",
                                                              space,
                                                              exit,
                                                              string ";"],
                                                         0) p
                               in
                                   box [body,
                                        box [string "{",
                                             newline,
                                             pr,
                                             newline,
                                             p,
                                             newline,
                                             string "result",
                                             space,
                                             string "=",
                                             space,
                                             p_exp env e,
                                             string ";",
                                             newline,
                                             string "goto",
                                             space,
                                             final,
                                             string ";",
                                             newline,
                                             string "}"],
                                        newline,
                                        exit,
                                        string ":",
                                        newline]
                               end) (box []) pes
        in
            box [string "({",
                 newline,
                 p_typ env disc,
                 space,
                 string "disc0",
                 space,
                 string "=",
                 space,
                 p_exp env e,
                 string ";",
                 newline,
                 p_typ env result,
                 space,
                 string "result;",
                 newline,
                 body,
                 string "uw_error(ctx, FATAL, \"",
                 string (ErrorMsg.spanToString loc),
                 string ": pattern match failure\");",
                 newline,
                 final,
                 string ":",
                 space,
                 string "result;",
                 newline,
                 string "})"]
        end

      | EWrite e => box [string "(uw_write(ctx, ",
                         p_exp env e,
                         string "), uw_unit_v)"]

      | ESeq (e1, e2) => box [string "(",
                              p_exp env e1,
                              string ",",
                              space,
                              p_exp env e2,
                              string ")"]
      | ELet (x, t, e1, e2) => box [string "({",
                                    newline,
                                    p_typ env t,
                                    space,
                                    string "__uwr_",
                                    p_ident x,
                                    string "_",
                                    string (Int.toString (E.countERels env)),
                                    space,
                                    string "=",
                                    space,
                                    p_exp env e1,
                                    string ";",
                                    newline,
                                    p_exp (E.pushERel env x t) e2,
                                    string ";",
                                    newline,
                                    string "})"]

      | EQuery {exps, tables, rnum, state, query, body, initial, prepared} =>
        let
            val exps = map (fn (x, t) => ("__uwf_" ^ ident x, t)) exps
            val tables = ListUtil.mapConcat (fn (x, xts) =>
                                                map (fn (x', t) => ("__uwf_" ^ ident x ^ ".__uwf_" ^ ident x', t)) xts)
                                            tables
                                                                                              
            val outputs = exps @ tables
            val outputs = ListMergeSort.sort (fn ((s1, _), (s2, _)) => String.compare (s1, s2) = GREATER) outputs

            val wontLeakStrings = notLeaky env true state
            val wontLeakAnything = notLeaky env false state
        in
            box [string "(uw_begin_region(ctx), ",
                 if wontLeakAnything then
                     string "uw_begin_region(ctx), "
                 else
                     box [],
                 string "({",
                 newline,
                 string "PGconn *conn = uw_get_db(ctx);",
                 newline,
                 case prepared of
                     NONE => box [string "char *query = ",
                                  p_exp env query,
                                  string ";",
                                  newline]
                   | SOME _ =>
                     let
                         val ets = getPargs query
                     in
                         box [p_list_sepi newline
                                          (fn i => fn (e, t) =>
                                                      box [p_sql_type t,
                                                           space,
                                                           string "arg",
                                                           string (Int.toString (i + 1)),
                                                           space,
                                                           string "=",
                                                           space,
                                                           p_exp env e,
                                                           string ";"])
                                          ets,
                              newline,
                              newline,

                              string "const char *paramValues[] = { ",
                              p_list_sepi (box [string ",", space])
                              (fn i => fn (_, t) => p_ensql t (box [string "arg",
                                                                    string (Int.toString (i + 1))]))
                              ets,
                              string " };",
                              newline,
                              newline]
                     end,
                 string "int n, i;",
                 newline,
                 p_typ env state,
                 space,
                 string "acc",
                 space,
                 string "=",
                 space,
                 p_exp env initial,
                 string ";",
                 newline,
                 string "PGresult *res = ",
                 case prepared of
                     NONE => string "PQexecParams(conn, query, 0, NULL, NULL, NULL, NULL, 0);"
                   | SOME n => box [string "PQexecPrepared(conn, \"uw",
                                    string (Int.toString n),
                                    string "\", ",
                                    string (Int.toString (length (getPargs query))),
                                    string ", paramValues, NULL, NULL, 0);"],
                 newline,
                 newline,

                 string "if (res == NULL) uw_error(ctx, FATAL, \"Out of memory allocating query result.\");",
                 newline,
                 newline,

                 string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                 newline,
                 box [string "PQclear(res);",
                      newline,
                      string "uw_error(ctx, FATAL, \"",
                      string (ErrorMsg.spanToString loc),
                      string ": Query failed:\\n%s\\n%s\", ",
                      case prepared of
                          NONE => string "query"
                        | SOME _ => p_exp env query,
                      string ", PQerrorMessage(conn));",
                      newline],
                 string "}",
                 newline,
                 newline,

                 string "uw_end_region(ctx);",
                 newline,
                 string "uw_push_cleanup(ctx, (void (*)(void *))PQclear, res);",
                 newline,
                 string "n = PQntuples(res);",
                 newline,
                 string "for (i = 0; i < n; ++i) {",
                 newline,
                 box [string "struct",
                      space,
                      string "__uws_",
                      string (Int.toString rnum),
                      space,
                      string "__uwr_r_",
                      string (Int.toString (E.countERels env)),
                      string ";",
                      newline,
                      p_typ env state,
                      space,
                      string "__uwr_acc_",
                      string (Int.toString (E.countERels env + 1)),
                      space,
                      string "=",
                      space,
                      string "acc;",
                      newline,
                      newline,

                      p_list_sepi (box []) (fn i =>
                                            fn (proj, t) =>
                                               box [string "__uwr_r_",
                                                    string (Int.toString (E.countERels env)),
                                                    string ".",
                                                    string proj,
                                                    space,
                                                    string "=",
                                                    space,
                                                    p_getcol wontLeakStrings env t i,
                                                    string ";",
                                                    newline]) outputs,
             
                      newline,
                      newline,

                      string "acc",
                      space,
                      string "=",
                      space,
                      p_exp (E.pushERel
                                 (E.pushERel env "r" (TRecord rnum, loc))
                                 "acc" state) 
                            body,
                      string ";",
                      newline],
                 string "}",
                 newline,
                 newline,
                 string "uw_pop_cleanup(ctx);",
                 newline,
                 if wontLeakAnything then
                     box [string "uw_end_region(ctx);",
                          newline]
                 else
                     box [],
                 string "acc;",
                 newline,
                 string "}))"]
        end

      | EDml {dml, prepared} =>
        box [string "(uw_begin_region(ctx), ({",
             newline,
             string "PGconn *conn = uw_get_db(ctx);",
             newline,
             case prepared of
                 NONE => box [string "char *dml = ",
                              p_exp env dml,
                              string ";",
                              newline]
               | SOME _ =>
                 let
                     val ets = getPargs dml
                 in
                     box [p_list_sepi newline
                                      (fn i => fn (e, t) =>
                                                  box [p_sql_type t,
                                                       space,
                                                       string "arg",
                                                       string (Int.toString (i + 1)),
                                                       space,
                                                       string "=",
                                                       space,
                                                       p_exp env e,
                                                       string ";"])
                                      ets,
                          newline,
                          newline,

                          string "const char *paramValues[] = { ",
                          p_list_sepi (box [string ",", space])
                                      (fn i => fn (_, t) => p_ensql t (box [string "arg",
                                                                            string (Int.toString (i + 1))]))
                                      ets,
                          string " };",
                          newline,
                          newline]
                 end,
             newline,
             newline,
             string "PGresult *res = ",
             case prepared of
                 NONE => string "PQexecParams(conn, dml, 0, NULL, NULL, NULL, NULL, 0);"
               | SOME n => box [string "PQexecPrepared(conn, \"uw",
                                string (Int.toString n),
                                string "\", ",
                                string (Int.toString (length (getPargs dml))),
                                string ", paramValues, NULL, NULL, 0);"],
             newline,
             newline,

             string "if (res == NULL) uw_error(ctx, FATAL, \"Out of memory allocating DML result.\");",
             newline,
             newline,

             string "if (PQresultStatus(res) != PGRES_COMMAND_OK) {",
             newline,
             box [string "PQclear(res);",
                  newline,
                  string "uw_error(ctx, FATAL, \"",
                  string (ErrorMsg.spanToString loc),
                  string ": DML failed:\\n%s\\n%s\", ",
                  case prepared of
                      NONE => string "dml"
                    | SOME _ => p_exp env dml,
                  string ", PQerrorMessage(conn));",
                  newline],
             string "}",
             newline,
             newline,

             string "PQclear(res);",
             newline,
             string "uw_end_region(ctx);",
             newline,
             string "uw_unit_v;",
             newline,
             string "}))"]

      | ENextval {seq, prepared} =>
        let
            val query = case seq of
                            (EPrim (Prim.String s), loc) =>
                            (EPrim (Prim.String ("SELECT NEXTVAL('" ^ s ^ "')")), loc)
                          | _ =>
                            let
                                val query = (EFfiApp ("Basis", "strcat", [seq, (EPrim (Prim.String "')"), loc)]), loc)
                            in
                                (EFfiApp ("Basis", "strcat", [(EPrim (Prim.String "SELECT NEXTVAL('"), loc), query]), loc)
                            end
        in
            box [string "(uw_begin_region(ctx), ",
                 string "({",
                 newline,
                 string "PGconn *conn = uw_get_db(ctx);",
                 newline,
                 case prepared of
                     NONE => box [string "char *query = ",
                                  p_exp env query,
                                  string ";",
                                  newline]
                   | SOME _ =>
                     box [],
                 newline,
                 string "PGresult *res = ",
                 case prepared of
                     NONE => string "PQexecParams(conn, query, 0, NULL, NULL, NULL, NULL, 0);"
                   | SOME n => box [string "PQexecPrepared(conn, \"uw",
                                    string (Int.toString n),
                                    string "\", 0, NULL, NULL, NULL, 0);"],
                 newline,
                 string "uw_Basis_int n;",
                 newline,
                 newline,

                 string "if (res == NULL) uw_error(ctx, FATAL, \"Out of memory allocating nextval result.\");",
                 newline,
                 newline,

                 string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                 newline,
                 box [string "PQclear(res);",
                      newline,
                      string "uw_error(ctx, FATAL, \"",
                      string (ErrorMsg.spanToString loc),
                      string ": Query failed:\\n%s\\n%s\", ",
                      case prepared of
                          NONE => string "query"
                        | SOME _ => p_exp env query,
                      string ", PQerrorMessage(conn));",
                      newline],
                 string "}",
                 newline,
                 newline,

                 string "uw_end_region(ctx);",
                 newline,
                 string "n = PQntuples(res);",
                 newline,
                 string "if (n != 1) {",
                 newline,
                 box [string "PQclear(res);",
                      newline,
                      string "uw_error(ctx, FATAL, \"",
                      string (ErrorMsg.spanToString loc),
                      string ": Wrong number of result rows:\\n%s\\n%s\", ",
                      case prepared of
                          NONE => string "query"
                        | SOME _ => p_exp env query,
                      string ", PQerrorMessage(conn));",
                      newline],
                 string "}",
                 newline,
                 newline,

                 string "n = ",
                 p_unsql true env (TFfi ("Basis", "int"), loc)
                         (string "PQgetvalue(res, 0, 0)"),
                 string ";",
                 newline,
                 string "PQclear(res);",
                 newline,
                 string "n;",
                 newline,
                 string "}))"]
        end

      | EUnurlify (e, t) =>
        let
            fun getIt () =
                if isUnboxable t then
                    unurlify env t
                else
                    box [string "({",
                         newline,
                         p_typ env t,
                         string " *tmp = uw_malloc(ctx, sizeof(",
                         p_typ env t,
                         string "));",
                         newline,
                         string "*tmp = ",
                         unurlify env t,
                         string ";",
                         newline,
                         string "tmp;",
                         newline,
                         string "})"]
        in
            box [string "({",
                 newline,
                 string "uw_Basis_string request = uw_Basis_maybe_strdup(ctx, ",
                 p_exp env e,
                 string ");",
                 newline,
                 newline,
                 string "(request ? ",
                 getIt (),
                 string " : NULL);",
                 newline,
                 string "})"]
        end

and p_exp env = p_exp' false env

fun p_fun env (fx, n, args, ran, e) =
    let
        val nargs = length args
        val env' = foldl (fn ((x, dom), env) => E.pushERel env x dom) env args
    in
        box [string "static",
             space,
             p_typ env ran,
             space,
             string ("__uwn_" ^ ident fx ^ "_" ^ Int.toString n),
             string "(",
             p_list_sep (box [string ",", space]) (fn x => x)
                        (string "uw_context ctx" :: ListUtil.mapi (fn (i, (_, dom)) =>
                                                                      box [p_typ env dom,
                                                                           space,
                                                                           p_rel env' (nargs - i - 1)]) args),
             string ")",
             space,
             string "{",
             newline,
             box[string "return(",
                 p_exp env' e,
                 string ");"],
             newline,
             string "}"]
    end

fun p_decl env (dAll as (d, _) : decl) =
    case d of
        DStruct (n, xts) =>
        let
            val env = E.declBinds env dAll
        in
            box [string "struct",
                 space,
                 string ("__uws_" ^ Int.toString n),
                 space,
                 string "{",
                 newline,
                 p_list_sep (box []) (fn (x, t) => box [p_typ env t,
                                                        space,
                                                        string "__uwf_",
                                                        p_ident x,
                                                        string ";",
                                                        newline]) xts,
                 string "};"]
        end
      | DDatatype (Enum, x, n, xncs) =>
        box [string "enum",
             space,
             string ("__uwe_" ^ ident x ^ "_" ^ Int.toString n),
             space,
             string "{",
             space,
             p_list_sep (box [string ",", space]) (fn (x, n, _) =>
                                                      string ("__uwc_" ^ ident x ^ "_" ^ Int.toString n)) xncs,
             space,
             string "};"]
      | DDatatype (Option, _, _, _) => box []
      | DDatatype (Default, x, n, xncs) =>
        let
            val xncsArgs = List.mapPartial (fn (x, n, NONE) => NONE
                                             | (x, n, SOME t) => SOME (x, n, t)) xncs
        in
            box [string "enum",
                 space,
                 string ("__uwe_" ^ ident x ^ "_" ^ Int.toString n),
                 space,
                 string "{",
                 space,
                 p_list_sep (box [string ",", space]) (fn (x, n, _) =>
                                                          string ("__uwc_" ^ ident x ^ "_" ^ Int.toString n)) xncs,
                 space,
                 string "};",
                 newline,
                 newline,
                 string "struct",
                 space,
                 string ("__uwd_" ^ ident x ^ "_" ^ Int.toString n),
                 space,
                 string "{",
                 newline,
                 string "enum",
                 space,
                 string ("__uwe_" ^ ident x ^ "_" ^ Int.toString n),
                 space,
                 string "tag;",
                 newline,
                 box (case xncsArgs of
                          [] => []
                        | _ => [string "union",
                                space,
                                string "{",
                                newline,
                                p_list_sep newline (fn (x, n, t) => box [p_typ env t,
                                                                         space,
                                                                         string ("uw_" ^ ident x),
                                                                         string ";"]) xncsArgs,
                                newline,
                                string "}",
                                space,
                                string "data;",
                                newline]),
                 string "};"]
        end

      | DDatatypeForward _ => box []

      | DVal (x, n, t, e) =>
        box [p_typ env t,
             space,
             string ("__uwn_" ^ ident x ^ "_" ^ Int.toString n),
             space,
             string "=",
             space,
             p_exp env e,
             string ";"]
      | DFun vi => p_fun env vi
      | DFunRec vis =>
        let
            val env = E.declBinds env dAll
        in
            box [p_list_sep newline (fn (fx, n, args, ran, _) =>
                                        box [string "static",
                                             space,
                                             p_typ env ran,
                                             space,
                                             string ("__uwn_" ^ ident fx ^ "_" ^ Int.toString n),
                                             string "(uw_context,",
                                             space,
                                             p_list_sep (box [string ",", space])
                                                        (fn (_, dom) => p_typ env dom) args,
                                             string ");"]) vis,
                 newline,
                 p_list_sep newline (p_fun env) vis,
                 newline]
        end
      | DTable (x, _) => box [string "/* SQL table ",
                              string x,
                              string " */",
                              newline]
      | DSequence x => box [string "/* SQL sequence ",
                            string x,
                            string " */",
                            newline]
      | DDatabase s => box [string "static void uw_db_validate(uw_context);",
                            newline,
                            string "static void uw_db_prepare(uw_context);",
                            newline,
                            newline,
                            string "void uw_db_init(uw_context ctx) {",
                            newline,
                            string "PGconn *conn = PQconnectdb(\"",
                            string (String.toString s),
                            string "\");",
                            newline,
                            string "if (conn == NULL) uw_error(ctx, BOUNDED_RETRY, ",
                            string "\"libpq can't allocate a connection.\");",
                            newline,
                            string "if (PQstatus(conn) != CONNECTION_OK) {",
                            newline,
                            box [string "char msg[1024];",
                                 newline,
                                 string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                 newline,
                                 string "msg[1023] = 0;",
                                 newline,
                                 string "PQfinish(conn);",
                                 newline,
                                 string "uw_error(ctx, BOUNDED_RETRY, ",
                                 string "\"Connection to Postgres server failed: %s\", msg);"],
                            newline,
                            string "}",
                            newline,
                            string "uw_set_db(ctx, conn);",
                            newline,
                            string "uw_db_validate(ctx);",
                            newline,
                            string "uw_db_prepare(ctx);",
                            newline,
                            string "}",
                            newline,
                            newline,
                            string "void uw_db_close(uw_context ctx) {",
                            newline,
                            string "PQfinish(uw_get_db(ctx));",
                            newline,
                            string "}",
                            newline,
                            newline,

                            string "int uw_db_begin(uw_context ctx) {",
                            newline,
                            string "PGconn *conn = uw_get_db(ctx);",
                            newline,
                            string "PGresult *res = PQexec(conn, \"BEGIN\");",
                            newline,
                            newline,
                            string "if (res == NULL) return 1;",
                            newline,
                            newline,
                            string "if (PQresultStatus(res) != PGRES_COMMAND_OK) {",
                            box [string "PQclear(res);",
                                 newline,
                                 string "return 1;",
                                 newline],
                            string "}",
                            newline,
                            string "return 0;",
                            newline,
                            string "}",
                            newline,
                            newline,

                            string "int uw_db_commit(uw_context ctx) {",
                            newline,
                            string "PGconn *conn = uw_get_db(ctx);",
                            newline,
                            string "PGresult *res = PQexec(conn, \"COMMIT\");",
                            newline,
                            newline,
                            string "if (res == NULL) return 1;",
                            newline,
                            newline,
                            string "if (PQresultStatus(res) != PGRES_COMMAND_OK) {",
                            box [string "PQclear(res);",
                                 newline,
                                 string "return 1;",
                                 newline],
                            string "}",
                            newline,
                            string "return 0;",
                            newline,
                            string "}",
                            newline,
                            newline,

                            string "int uw_db_rollback(uw_context ctx) {",
                            newline,
                            string "PGconn *conn = uw_get_db(ctx);",
                            newline,
                            string "PGresult *res = PQexec(conn, \"ROLLBACK\");",
                            newline,
                            newline,
                            string "if (res == NULL) return 1;",
                            newline,
                            newline,
                            string "if (PQresultStatus(res) != PGRES_COMMAND_OK) {",
                            box [string "PQclear(res);",
                                 newline,
                                 string "return 1;",
                                 newline],
                            string "}",
                            newline,
                            string "return 0;",
                            newline,
                            string "}",
                            newline]

      | DPreparedStatements [] =>
        box [string "static void uw_db_prepare(uw_context ctx) {",
             newline,
             string "}"]
      | DPreparedStatements ss =>
        box [string "static void uw_db_prepare(uw_context ctx) {",
             newline,
             string "PGconn *conn = uw_get_db(ctx);",
             newline,
             string "PGresult *res;",
             newline,
             newline,

             p_list_sepi newline (fn i => fn (s, n) =>
                                             box [string "res = PQprepare(conn, \"uw",
                                                  string (Int.toString i),
                                                  string "\", \"",
                                                  string (String.toString s),
                                                  string "\", ",
                                                  string (Int.toString n),
                                                  string ", NULL);",
                                                  newline,
                                                  string "if (PQresultStatus(res) != PGRES_COMMAND_OK) {",
                                                  newline,
                                                  box [string "char msg[1024];",
                                                       newline,
                                                       string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                                       newline,
                                                       string "msg[1023] = 0;",
                                                       newline,
                                                       string "PQclear(res);",
                                                       newline,
                                                       string "PQfinish(conn);",
                                                       newline,
                                                       string "uw_error(ctx, FATAL, \"Unable to create prepared statement:\\n",
                                                       string (String.toString s),
                                                       string "\\n%s\", msg);",
                                                       newline],
                                                  string "}",
                                                  newline,
                                                  string "PQclear(res);",
                                                  newline])
                         ss,
             
             string "}"]

datatype 'a search =
         Found of 'a
       | NotFound
       | Error

fun p_sqltype'' env (tAll as (t, loc)) =
    case t of
        TFfi ("Basis", "int") => "int8"
      | TFfi ("Basis", "float") => "float8"
      | TFfi ("Basis", "string") => "text"
      | TFfi ("Basis", "bool") => "bool"
      | TFfi ("Basis", "time") => "timestamp"
      | _ => (ErrorMsg.errorAt loc "Don't know SQL equivalent of type";
              Print.eprefaces' [("Type", p_typ env tAll)];
              "ERROR")

fun p_sqltype' env (tAll as (t, loc)) =
    case t of
        (TOption t, _) => p_sqltype'' env t
      | _ => p_sqltype'' env t ^ " NOT NULL"

fun p_sqltype env t = string (p_sqltype' env t)

fun p_sqltype_base' env t =
    case t of
        (TOption t, _) => p_sqltype'' env t
      | _ => p_sqltype'' env t

fun p_sqltype_base env t = string (p_sqltype_base' env t)

fun is_not_null t =
    case t of
        (TOption _, _) => false
      | _ => true

fun p_file env (ds, ps) =
    let
        val (pds, env) = ListUtil.foldlMap (fn (d, env) =>
                                             (p_decl env d,
                                              E.declBinds env d))
                             env ds

        val fields = foldl (fn ((ek, _, _, ts), fields) =>
                               case ek of
                                   Core.Link => fields
                                 | Core.Action =>
                                   case List.nth (ts, length ts - 2) of
                                       (TRecord i, _) =>
                                       let
                                           val xts = E.lookupStruct env i
                                           val xtsSet = SS.addList (SS.empty, map #1 xts)
                                       in
                                           foldl (fn ((x, _), fields) =>
                                                     let
                                                         val xtsSet' = Option.getOpt (SM.find (fields, x), SS.empty)
                                                     in
                                                         SM.insert (fields, x, SS.union (SS.delete (xtsSet, x),
                                                                                         xtsSet'))
                                                     end) fields xts
                                       end
                                     | _ => raise Fail "CjrPrint: Last argument of action isn't record")
                     SM.empty ps

        val fnums = SM.foldli (fn (x, xs, fnums) =>
                                  let
                                      val unusable = SS.foldl (fn (x', unusable) =>
                                                                  case SM.find (fnums, x') of
                                                                      NONE => unusable
                                                                    | SOME n => IS.add (unusable, n))
                                                     IS.empty xs

                                      fun findAvailable n =
                                          if IS.member (unusable, n) then
                                              findAvailable (n + 1)
                                          else
                                              n
                                  in
                                      SM.insert (fnums, x, findAvailable 0)
                                  end)
                    SM.empty fields

        fun makeSwitch (fnums, i) =
            case SM.foldl (fn (n, NotFound) => Found n
                            | (n, Error) => Error
                            | (n, Found n') => if n = n' then
                                                  Found n'
                                               else
                                                   Error) NotFound fnums of
                NotFound => box [string "return",
                                 space,
                                 string "-1;"]
              | Found n => box [string "return",
                                space,
                                string (Int.toString n),
                                string ";"]
              | Error =>
                let
                    val cmap = SM.foldli (fn (x, n, cmap) =>
                                             let
                                                 val ch = if i < size x then
                                                              String.sub (x, i)
                                                          else
                                                              chr 0

                                                 val fnums = case CM.find (cmap, ch) of
                                                                 NONE => SM.empty
                                                               | SOME fnums => fnums
                                                 val fnums = SM.insert (fnums, x, n)
                                             in
                                                 CM.insert (cmap, ch, fnums)
                                             end)
                               CM.empty fnums

                    val cmap = CM.listItemsi cmap
                in
                    case cmap of
                        [(_, fnums)] =>
                        box [string "if",
                             space,
                             string "(name[",
                             string (Int.toString i),
                             string "]",
                             space,
                             string "==",
                             space,
                             string "0)",
                             space,
                             string "return",
                             space,
                             string "-1;",
                             newline,
                             makeSwitch (fnums, i+1)]
                      | _ =>
                        box [string "switch",
                             space,
                             string "(name[",
                             string (Int.toString i),
                             string "])",
                             space,
                             string "{",
                             newline,
                             box (map (fn (ch, fnums) =>
                                          box [string "case",
                                               space,
                                               if ch = chr 0 then
                                                   string "0:"
                                               else
                                                   box [string "'",
                                                        string (Char.toString ch),
                                                        string "':"],
                                               newline,
                                               makeSwitch (fnums, i+1),
                                               newline]) cmap),
                             string "default:",
                             newline,
                             string "return",
                             space,
                             string "-1;",
                             newline,
                             string "}"]
                end

        fun p_page (ek, s, n, ts) =
            let
                val (ts, defInputs, inputsVar) =
                    case ek of
                        Core.Link => (List.take (ts, length ts - 1), string "", string "")
                      | Core.Action =>
                        case List.nth (ts, length ts - 2) of
                            (TRecord i, _) =>
                            let
                                val xts = E.lookupStruct env i
                            in
                                (List.take (ts, length ts - 2),
                                 box [box (map (fn (x, t) => box [p_typ env t,
                                                                  space,
                                                                  string "uw_input_",
                                                                  p_ident x,
                                                                  string ";",
                                                                  newline]) xts),
                                      newline,
                                      box (map (fn (x, t) =>
                                                   let
                                                       val n = case SM.find (fnums, x) of
                                                                   NONE => raise Fail "CjrPrint: Can't find in fnums"
                                                                 | SOME n => n

                                                       val f = case t of
                                                                   (TFfi ("Basis", "bool"), _) => "optional_"
                                                                 | _ => ""
                                                   in
                                                       box [string "request = uw_get_",
                                                            string f,
                                                            string "input(ctx, ",
                                                            string (Int.toString n),
                                                            string ");",
                                                            newline,
                                                            string "if (request == NULL)",
                                                            newline,
                                                            box [string "uw_error(ctx, FATAL, \"Missing input ",
                                                                 string x,
                                                                 string "\");"],
                                                            newline,
                                                            string "uw_input_",
                                                            p_ident x,
                                                            space,
                                                            string "=",
                                                            space,
                                                            unurlify env t,
                                                            string ";",
                                                            newline]
                                                   end) xts),
                                      string "struct __uws_",
                                      string (Int.toString i),
                                      space,
                                      string "uw_inputs",
                                      space,
                                      string "= {",
                                      newline,
                                      box (map (fn (x, _) => box [string "uw_input_",
                                                                  p_ident x,
                                                                  string ",",
                                                                  newline]) xts),
                                      string "};",
                                      newline],
                                 box [string ",",
                                      space,
                                      string "uw_inputs"])
                            end

                          | _ => raise Fail "CjrPrint: Last argument to an action isn't a record"
            in
                box [string "if (!strncmp(request, \"",
                     string (String.toString s),
                     string "\", ",
                     string (Int.toString (size s)),
                     string ") && (request[",
                     string (Int.toString (size s)),
                     string "] == 0 || request[",
                     string (Int.toString (size s)),
                     string "] == '/')) {",
                     newline,
                     string "request += ",
                     string (Int.toString (size s)),
                     string ";",
                     newline,
                     string "if (*request == '/') ++request;",
                     newline,
                     box [string "{",
                          newline,
                          box (ListUtil.mapi (fn (i, t) => box [p_typ env t,
                                                                space,
                                                                string "arg",
                                                                string (Int.toString i),
                                                                space,
                                                                string "=",
                                                                space,
                                                                unurlify env t,
                                                                string ";",
                                                                newline]) ts),
                          defInputs,
                          p_enamed env n,
                          string "(",
                          p_list_sep (box [string ",", space])
                                     (fn x => x)
                                     (string "ctx"
                                      :: ListUtil.mapi (fn (i, _) => string ("arg" ^ Int.toString i)) ts),
                          inputsVar,
                          string ", uw_unit_v);",
                          newline,
                          string "return;",
                          newline,
                          string "}",
                          newline,
                          string "}"]
                    ]
            end

        val pds' = map p_page ps

        val tables = List.mapPartial (fn (DTable (s, xts), _) => SOME (s, xts)
                                       | _ => NONE) ds
        val sequences = List.mapPartial (fn (DSequence s, _) => SOME s
                                          | _ => NONE) ds

        val validate =
            box [string "static void uw_db_validate(uw_context ctx) {",
                 newline,
                 string "PGconn *conn = uw_get_db(ctx);",
                 newline,
                 string "PGresult *res;",
                 newline,
                 newline,
                 p_list_sep newline
                            (fn (s, xts) =>
                                let
                                    val sl = CharVector.map Char.toLower s

                                    val q = "SELECT COUNT(*) FROM pg_class WHERE relname = '"
                                            ^ sl ^ "'"

                                    val q' = String.concat ["SELECT COUNT(*) FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = '",
                                                            sl,
                                                            "') AND (",
                                                            String.concatWith " OR "
                                                              (map (fn (x, t) =>
                                                                       String.concat ["(attname = 'uw_",
                                                                                      CharVector.map
                                                                                          Char.toLower (ident x),
                                                                                      "' AND atttypid = (SELECT oid FROM pg_type",
                                                                                      " WHERE typname = '",
                                                                                      p_sqltype_base' env t,
                                                                                      "') AND attnotnull = ",
                                                                                      if is_not_null t then
                                                                                          "TRUE"
                                                                                      else
                                                                                          "FALSE",
                                                                                      ")"]) xts),
                                                            ")"]

                                    val q'' = String.concat ["SELECT COUNT(*) FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = '",
                                                             sl,
                                                             "') AND attname LIKE 'uw_%'"]
                                in
                                    box [string "res = PQexec(conn, \"",
                                         string q,
                                         string "\");",
                                         newline,
                                         newline,
                                         string "if (res == NULL) {",
                                         newline,
                                         box [string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Out of memory allocating query result.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                                         newline,
                                         box [string "char msg[1024];",
                                              newline,
                                              string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                              newline,
                                              string "msg[1023] = 0;",
                                              newline,
                                              string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Query failed:\\n",
                                              string q,
                                              string "\\n%s\", msg);",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (strcmp(PQgetvalue(res, 0, 0), \"1\")) {",
                                         newline,
                                         box [string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Table '",
                                              string s,
                                              string "' does not exist.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "PQclear(res);",
                                         newline,

                                         string "res = PQexec(conn, \"",
                                         string q',
                                         string "\");",
                                         newline,
                                         newline,
                                         string "if (res == NULL) {",
                                         newline,
                                         box [string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Out of memory allocating query result.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                                         newline,
                                         box [string "char msg[1024];",
                                              newline,
                                              string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                              newline,
                                              string "msg[1023] = 0;",
                                              newline,
                                              string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Query failed:\\n",
                                              string q',
                                              string "\\n%s\", msg);",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (strcmp(PQgetvalue(res, 0, 0), \"",
                                         string (Int.toString (length xts)),
                                         string "\")) {",
                                         newline,
                                         box [string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Table '",
                                              string s,
                                              string "' has the wrong column types.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "PQclear(res);",
                                         newline,
                                         newline,

                                         string "res = PQexec(conn, \"",
                                         string q'',
                                         string "\");",
                                         newline,
                                         newline,
                                         string "if (res == NULL) {",
                                         newline,
                                         box [string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Out of memory allocating query result.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                                         newline,
                                         box [string "char msg[1024];",
                                              newline,
                                              string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                              newline,
                                              string "msg[1023] = 0;",
                                              newline,
                                              string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Query failed:\\n",
                                              string q'',
                                              string "\\n%s\", msg);",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (strcmp(PQgetvalue(res, 0, 0), \"",
                                         string (Int.toString (length xts)),
                                         string "\")) {",
                                         newline,
                                         box [string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Table '",
                                              string s,
                                              string "' has extra columns.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "PQclear(res);",
                                         newline]
                                end) tables,

                 p_list_sep newline
                            (fn s =>
                                let
                                    val sl = CharVector.map Char.toLower s

                                    val q = "SELECT COUNT(*) FROM pg_class WHERE relname = '"
                                            ^ sl ^ "' AND relkind = 'S'"
                                in
                                    box [string "res = PQexec(conn, \"",
                                         string q,
                                         string "\");",
                                         newline,
                                         newline,
                                         string "if (res == NULL) {",
                                         newline,
                                         box [string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Out of memory allocating query result.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (PQresultStatus(res) != PGRES_TUPLES_OK) {",
                                         newline,
                                         box [string "char msg[1024];",
                                              newline,
                                              string "strncpy(msg, PQerrorMessage(conn), 1024);",
                                              newline,
                                              string "msg[1023] = 0;",
                                              newline,
                                              string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Query failed:\\n",
                                              string q,
                                              string "\\n%s\", msg);",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "if (strcmp(PQgetvalue(res, 0, 0), \"1\")) {",
                                         newline,
                                         box [string "PQclear(res);",
                                              newline,
                                              string "PQfinish(conn);",
                                              newline,
                                              string "uw_error(ctx, FATAL, \"Sequence '",
                                              string s,
                                              string "' does not exist.\");",
                                              newline],
                                         string "}",
                                         newline,
                                         newline,
                                         string "PQclear(res);",
                                         newline]
                                end) sequences,

                 string "}"]

        val hasDb = List.exists (fn (DDatabase _, _) => true | _ => false) ds
    in
        box [string "#include <stdio.h>",
             newline,
             string "#include <stdlib.h>",
             newline,
             string "#include <string.h>",
             newline,
             string "#include <math.h>",
             newline,
             if hasDb then
                 box [string "#include <postgresql/libpq-fe.h>",
                      newline]
             else
                 box [],
             newline,
             string "#include \"",
             string (OS.Path.joinDirFile {dir = Config.includ,
                                          file = "urweb.h"}),
             string "\"",
             newline,
             newline,
             p_list_sep newline (fn x => x) pds,
             newline,
             string "int uw_inputs_len = ",
             string (Int.toString (SM.foldl Int.max 0 fnums + 1)),
             string ";",
             newline,
             newline,
             string "int uw_input_num(char *name) {",
             newline,
             makeSwitch (fnums, 0),
             string "}",
             newline,
             newline,
             string "void uw_handle(uw_context ctx, char *request) {",
             newline,
             p_list_sep newline (fn x => x) pds',
             newline,
             string "uw_error(ctx, FATAL, \"Unknown page\");",
             newline,
             string "}",
             newline,
             newline,
             if hasDb then
                 validate
             else
                 box [],
             newline,
             if List.exists (fn (DDatabase _, _) => true | _ => false) ds then
                 box []
             else
                 box [newline,
                      string "void uw_db_init(uw_context ctx) { };",
                      newline,
                      string "int uw_db_begin(uw_context ctx) { return 0; };",
                      newline,
                      string "int uw_db_commit(uw_context ctx) { return 0; };",
                      newline,
                      string "int uw_db_rollback(uw_context ctx) { return 0; };",
                      newline]]
    end

fun p_sql env (ds, _) =
    let
        val (pps, _) = ListUtil.foldlMap
                       (fn (dAll as (d, _), env) =>
                           let
                               val pp = case d of
                                            DTable (s, xts) =>
                                            box [string "CREATE TABLE ",
                                                 string s,
                                                 string "(",
                                                 p_list (fn (x, t) =>
                                                            box [string "uw_",
                                                                 string (CharVector.map Char.toLower x),
                                                                 space,
                                                                 p_sqltype env (t, ErrorMsg.dummySpan)]) xts,
                                                 string ");",
                                                 newline,
                                                 newline]
                                          | DSequence s =>
                                            box [string "CREATE SEQUENCE ",
                                                 string s,
                                                 string ";",
                                                 newline,
                                                 newline]
                                          | _ => box []
                           in
                               (pp, E.declBinds env dAll)
                           end)
                       env ds
    in
        box pps
    end

end