/*
  Copyright (c) 2008 Alessandro Warth <awarth@cs.ucla.edu>
*/

// TODO: make returns inside "in" statements work, e.g., function() { in w1 { return arr.printString() } }()
// in { ... } -> {if ((_inR = function($world) { ...; return _nothing }()) != _nothing) return _inR}

// TODO: for-in, (pre/post)-(in/de)crements, and modified assignments

eval(readFile("Worlds_Library"))

ometa WJSParser <: BSJSParser {
  isKeyword :x = ?(x == 'abort')
               | ?(x == 'world')
               | ?(x == 'scope')
               | super('isKeyword', x),
  primExprHd   = "world"                        -> ['world']
               | "scope"                        -> ['scope']
               | "new" "world"                  -> ['newWorld']
               | super('primExprHd'),
  stmt         = "abort"                        -> ['abort']
               | "try" block:tb "else" block:eb -> ['wtry', tb, eb]
               | "in" expr:w block:b            -> ['in', w, b]
               | super('stmt')
}

makeFunction = function(fs, body) {
  return '(function() { var $staticScope = $scope;'+
                      ' return function($world, $this) {' +
                               ' var $scope = $staticScope.makeChild();' +
                               fs + body + '}})()'
}

ometa WJSTranslator <: BSJSTranslator {
  initialize = { self.level = 0 },

  fargs = [anything*:fs]                           -> { var ss = []
                                                        fs.each(function(v, i) { ss.push('$scope.decl($world, "' + v +
                                                                                         '", arguments[' + (i + 2) + ']);') })
                                                        ss.join('') },
  trans = ['world']                                -> '$world'
        | ['scope']                                -> '$scope'
        | ['this']                                 -> '$this'
        | ['var' :n trans:v]                       -> ('$scope.decl($world, "' + n + '", ' + v + ')')
        | ['get' :n]                               -> ('$scope.get($world, "' + n + '")')
        | ['set' ['get' :n] trans:v]               -> ('$scope.set($world, "' + n + '", ' + v + ')')
        | ['getp' trans:p trans:x]                 -> ('$world.get(' + x + ', ' + p + ')')
        | ['set' ['getp' trans:p trans:x] trans:v] -> ('$world.set(' + x + ', ' + p + ', ' + v + ')')
        | ['call' trans+:f_and_as]                 -> ('$world.call(null, ' + f_and_as.join(',') + ')')
        | ['send' :m trans:r trans*:as]            -> ('$world.send(' + r + ', "' + m + '"' +
                                                                    as.map(function(a) { return ',' + a }).join('') + ')')
        | ['newWorld']                             -> ('$world.makeChild()')
        | ['new' :x trans*:as]                     -> ('newAndInitialize($world, $scope.get($world, "' + x + '")' +
                                                                    as.map(function(a) { return ',' + a }).join('') + ')')
        | ['func' fargs:fs
           {self.level++} trans:body
           {self.level--}]                         -> makeFunction(fs, body)
        | ['abort']                                -> 'throw abort'
        | ['wtry' trans:tb trans:te]               -> { var r = '$world.tryElse(function($world){' + tb + '; return nothing},' +
                                                                               'function($world){' + te + '; return nothing})'
                                                        self.level > 0 ? 'if (($_ = ' + r + ')!==nothing) return $_' : r }
        | ['in' trans:w trans:b]                   -> ('(function($world) {' + b + '})(' + w + ')')
        | ['arr'  trans*:xs]                       -> ('[' + xs.join(',') + '].toWJSArray()')
        | ['json' trans*:xs]                       -> ('({' + xs.join(',') + '}).toWJSObject()')
        | ~['mset'  anything*]
          ~['forIn' anything*]
          super('trans')
}

compileWJS = function(code) {
  var tree = WJSParser.matchAll(code, "topLevel", undefined, function(m, i) { throw fail.delegated({errorPos: i}) })
  return WJSTranslator.match(tree, 'trans')
}

$scope.decl($world, "eval",    function($world, $this, s) { return eval(compileWJS(s)) })
$scope.decl($world, "prompt",  function($world, $this, s) { return prompt(s) })
$scope.decl($world, "confirm", function($world, $this, s) { return confirm(s) })

translateCode = compileWJS




foo = new object()
foo.initialize = function(x) { alert("making a foo, x = " + x) }
new foo(1234)
foo.aaa = 5
new foo(1234).aaa
{x: 1}.x

function(x, y) {
console.log("before x=" + x + ", y=" + y)
try {
  x = 1
  y = 2
  console.log("during x=" + x + ", y=" + y)
  abort
}
else { console.log("aborted") }
console.log("after x=" + x + ", y=" + y)
}(1234, 4321)

// scopes are 1st class
scope.has("z")
scope.decl("z", 42)
scope.has("z")
scope.get("z")
scope.set("z", 1234)
z

// testing bool prototype
bool.isBool = true
true.isBool
({}).isBool

// testing number prototype
number.fact = function() { return this === 0 ? 1 : this * (this - 1).fact() }
5.fact()

// testing array prototype
array.push = function(x) {
  this.length = this.length + 1
  this[this.length - 1] = x
  return x
}
array.map = function(f) {
  var r = []
  for (var idx = 0; idx < this.length; idx = idx + 1)
    r.push(f(this[idx]))
  return r
}
array.reduce = function(f, z) {
  var r = z
  for (var idx = 0; idx < this.length; idx = idx + 1)
    r = f(r, this[idx]) 
  return r
}
[1, 2, 3].reduce(function(x, y) { return x + " " + y }, "")

// testing string prototype
string.shout = function() { alert("<<< " + this + " >>>") }
"hello".shout()


gensym = function() {
  gensym.count = gensym.count + 1
  return "_gensm_" + gensym.count
}
gensym.count = 0

scopeProto.unify = function(x, v) {
  if (this.has(x) && this.get(x) !== v)
    abort
  else return this.decl(x, v)
}

father = function(x, y, s, k) {
  try  { s.unify(x, "abe");   s.unify(y, "homer"); k(s) } else {
  try  { s.unify(x, "homer"); s.unify(y, "bart");  k(s) } else {
  try  { s.unify(x, "homer"); s.unify(y, "lisa");  k(s) } else {}}}
}
grandfather = function(x, y, s, k) {
  try { var z = gensym(); father(x, z, s, function(s) { father(z, y, s, k) }) }
  else {}
}

     father("a", "b", scope, function() { if (confirm("a=" + a + ", b=" + b + "\n\nmore results?")) abort })
grandfather("c", "d", scope, function() { if (confirm("c=" + c + ", c=" + c + "\n\nmore results?")) abort })