var mainModule;
var modules = {};

var nextmethodId = 0;
var methodIds = {};
function getMethodId(methodName)
{
	if (!(methodName in methodIds)) {
		methodIds[methodName] = nextmethodId++;
		
	}
	return methodIds[methodName];
}

function importSym(obj, src, key)
{
	if(!(key in src)) {
		throw new Error(key +' not found in source object for import');
	}
	if(key in obj) {
		throw new Error(key +' already exists in target object for import')
	}
	obj[key] = src[key];
}

function doImport(obj, src, symlist)
{
	if (symlist === undefined) {
		each(src, function(key,val) {
			if (key != 'parent') {
				importSym(obj, src, key);
			}
		});
	} else {
		for (var i = 0; i < symlist.length; ++i) {
			importSym(obj, src, symlist[i]);
		}
	}
	return obj;
}

op.prototype.toC = function(isReceiver) {
	var optoMeth = {'+': 'ADD_', '-': 'SUB_', '*': 'MUL_', '/': 'DIV_', '%': 'MOD_', '=': 'EQ_', '!=': 'NEQ_', '<': 'LT_', '>': 'GT_', '>=': 'GEQ_', '<=': 'LEQ_', '.': 'CAT_'};
	var method = optoMeth[this.op];
	return 'mcall(' + getMethodId(method) + '/* ' + method + ' */, 2, (object *)' + this.left.toC() + ', ' + this.right.toC() + ')\n';
};

function escapeCName(name)
{
	if (name == 'self') {
		return name;
	}
	name = name.replace("_", "UN_").replace(":", "CN_").replace("!", "EX_").replace('?', 'QS_').replace('@', 'AT_');
	name = 'tp_' + name;
	return name;
}

function getSymbolPrefix(info, symbols)
{
	var pre = '';
	switch(info.type) {
	case 'self':
		
		pre = (new symbol('self', symbols)).toC() + '->';
		break;
	case 'parent':
		pre = (new symbol('self', symbols)).toC() + '->header.';
		for (var i = 0; i < info.depth; ++i) {
			pre += (i ? '->' : '') + 'parent';
		}
		pre = '((' + info.selftype + ' *)' + pre + ')->';
		break;
	case 'upvar':
		pre = 'env->';
		for (var i = info.startdepth; i < info.depth; ++i) {
			pre += 'parent->';
		}
		break;
	case 'recupvar':
		if (info.subtype == 'object') {
			pre = 'self->env->';
		} else {
			//TODO: fill this case in if necessary
		}
		pre += getSymbolPrefix(info.parent);
	case 'closedover':
		pre = 'myenv->';
	}
	return pre;
}

symbol.prototype.toC = function() {
	var name = this.cleanName();
	var info = this.symbols.find(name);
	if (!info) {
		throw new Error('symbol ' + name + ' not found');
	}
	if (info.type == 'toplevel') {
		return toplevel.moduleVar(name);
	} else if (info.type == 'self' && info.def instanceof lambda) {
		return 'mcall(' + getMethodId(name) + '/* ' + name + ' */, 1, ' + (new symbol('self', this.symbols)).toC() + ')';
	} else if (info.type == 'parent' && info.def instanceof lambda) {
		var obj = (new symbol('self', this.symbols)).toC() + '->header.';
		for (var i = 0; i < info.depth; ++i) {
			obj += (i ? '->' : '') + 'parent';
		}
		return 'mcall(' + getMethodId(name) + '/* ' + name + ' */, 1, ' + obj + ')';
	}
	return getSymbolPrefix(info, this.symbols) + escapeCName(name);
}

var declaredInts = {};

intlit.prototype.toC = function() {
	var str = this.val < 0 ? 'neg_' + (0-this.val).toString() : this.val.toString();
	if (!(this.val in declaredInts)) {
		toplevelcode += 'obj_int32 int32_' + str + ' = {{&obj_int32_meta, NULL}, ' + this.val.toString() + '};\n';
		declaredInts[this.val] = true;
	}
	return '((object *)&int32_' + str + ')';
}

floatlit.prototype.toC = function() {
	return 'make_float(' + this.val.toString() + ')';
}

var declaredStrings = {};
var nextStringId = 0;

strlit.prototype.toC = function() {
	if (!(this.val in declaredStrings)) {
		//TODO: get the proper byte length
		toplevelcode += 'string str_' + nextStringId + ' = {{&string_meta, NULL}, ' + this.val.length + ', ' + this.val.length + ', "' + this.val.replace('\\', '\\\\').replace('"', '\\"').replace('\n', '\\n').replace('\r', '\\r') + '"};\n';
		declaredStrings[this.val] = nextStringId++;
	}
	return '((object *)&str_' + declaredStrings[this.val] + ')';
}

listlit.prototype.toC = function() {
	var ret = 'make_list(' + this.val.length;
	for (var i = 0; i < this.val.length; i++) {
		ret += ', ' + this.val[i].toC();
	}
	return ret + ')';
}

arraylit.prototype.toC = function() {
	var ret = 'make_array(' + this.val.length;
	for (var i = 0; i < this.val.length; i++) {
		ret += ', ' + this.val[i].toC();
	}
	return ret + ')';
}

funcall.prototype.toC = function() {
	var name = this.name[this.name.length-1] == ':' ? this.name.substr(0, this.name.length-1) : this.name;
	if (name == 'foreign') {
		if ((this.args[0] instanceof lambda) || (this.args[0] instanceof object)) {
			return null;
		} else if(this.args[0] instanceof symbol) {
			return this.args[0].name;
		} else {
			throw new Error("Unexpected AST type for foreign:");
		}
	}
	var args = this.args.slice(0, this.args.length);
	if (this.receiver) {
		args.splice(0, 0, this.receiver);
	}
	var method = false;
	var funinfo = this.symbols.find(name);
	if (!funinfo || funinfo.def instanceof setter) {
		method = true;
	} else {
		switch(funinfo.type)
		{
		case 'self':
			
			if (args.length < funinfo.def.args.length || !funinfo.def.args.length || funinfo.def.args[0].name != 'self') {
				args.splice(0, 0, new symbol('self', this.symbols));
			} else {
				args.splice(0, 1);
			}
			method = true;
			break;
		case 'parent':
			ret = 'self';
			for (var i = 0; i < funinfo.depth; ++i) {
				ret += '->parent';
			}
			break;
		}
	}
	for (var i in args) {
		args[i] = ', ' + args[i].toC();
	}
	var callpart;
	if (method) {
		callpart = 'mcall(' + getMethodId(name) + '/* ' + name + ' */';
	} else {
		callpart = 'ccall(' + (new symbol(name, this.symbols)).toC();
	}
	return callpart + ', ' + args.length + args.join('') + ')';
}

function cObject(name) {
	this.name = name;
	this.slots = {};
	this.properties = [];
	this.values = [];
	this.slotvars = {};
	this.includes = {};
	this.parent = 'NULL';
	this.init = [];
	this.initmsgadded = false;
}

cObject.prototype.addInclude = function(includefile) {
	this.includes[includefile] = true;
}

cObject.prototype.addMessage = function(msgname, implementation) {
	var methodid = getMethodId(msgname);
	var trunc = methodid & 0xF;
	if (!(trunc in this.slots)) {
		this.slots[trunc] = [];
	}
	this.slots[trunc].push([methodid, '\t\t' + implementation.lines.join('\n\t\t') + '\n', msgname]);
	if (!(trunc in this.slotvars)) {
		this.slotvars[trunc] = {};
	}
	for (var varname in implementation.vars) {
		this.slotvars[trunc][varname] = implementation.vars[varname];
	}
}

cObject.prototype.addProperty = function(propname, value, type) {
	if (type != undefined) {
		this.properties.push([propname, type]);
		if (value !== null) {
			this.values.push(value);
		}
	} else {
		var escaped = escapeCName(propname);
		this.addMessage(propname, {
			vars: {},
			lines: [
				'return self->' + escaped + ';'
		]});
		this.addMessage(propname + '!', {
			vars: {},
			lines: [
				'self->' + escaped + ' = va_arg(args, object *);',
				'return (object *)self;'
		]});
		this.properties.push(escaped);
		this.values.push(value);
	}
}

cObject.prototype.addInit = function(statement) {
	this.init.push(statement);
}

cObject.prototype.checkInitMsg = function() {
	if (!this.initmsgadded && this.init.length) {
		var init = this.init.slice(0, this.init.length);
		init.push('return (object *)self;');
		this.addMessage('_init', {
			vars: {},
			lines: init
		});		
		this.initmsgadded = true;
	}
}

cObject.prototype.populateSymbols = function() {};

cObject.prototype.toEarlyCDef = function() {
	this.checkInitMsg();
	var includes = '';
	for (var file in this.includes) {
		includes += '#include ' + file + '\n';
	}
	var objdef =  'typedef struct ' + this.name + ' {\n\tobject header;\n';
	for (var i in this.properties) {
		if (this.properties[i] instanceof Array) {
			objdef += '\t' + this.properties[i][1] + ' ' + this.properties[i][0] + ';\n';
		} else {
			objdef += '\tobject * ' + this.properties[i] + ';\n'
		}
	}
	objdef += '} ' + this.name + ';\nobj_meta ' + this.name + '_meta;\n';
	return includes + objdef;
}

cObject.prototype.toCDef = function() {
	this.checkInitMsg();
	var slotdefs = '';
	var metadef = 'obj_meta ' + this.name + '_meta = {sizeof(' + this.name +'), {';
	for (var i = 0; i < 16; i++) {
		if (i) {
			metadef += ', ';
		}
		if (i in this.slots) {
			slotdefs += 'object * ' + this.name + '_slot_' + i + '(uint32_t method_id, uint32_t num_params, object * oself, va_list args) {\n\t' +
				this.name + ' *self = (' + this.name + ' *)oself;\n';
			for (var varname in this.slotvars[i]) {
				slotdefs += '\t' + this.slotvars[i][varname] + ' ' + varname + ';\n';
			}
			if (this.slots[i].length == 1) {
				slotdefs += '\tif (method_id == ' + this.slots[i][0][0] + ') { /* ' + this.slots[i][0][2] + '*/\n' +
					'\t\t' + this.slots[i][0][1] + '\n' + 
					'\t}\n' +
					'\treturn no_impl(method_id, num_params, (object *)self, args);\n}\n';
			} else {
				slotdefs += '\tswitch(method_id) {\n';
				for (j in this.slots[i]) {
					slotdefs += '\t\tcase ' + this.slots[i][j][0] + ': /* ' + this.slots[i][j][2] + '*/\n' +
						'\t\t\t' + this.slots[i][j][1] + '\n';
				}
				slotdefs += '\t\tdefault:\n' +
					'\t\t\treturn no_impl(method_id, num_params, (object *)self, args);\n\t}\n}\n';
					
			}
			metadef += this.name + '_slot_' + i;
		} else {
			metadef += 'no_impl';
		}
	}
	metadef += '}};\n';
	return slotdefs + metadef;
}

cObject.prototype.toCInstance = function() {
	this.checkInitMsg();
	var ret = 'make_object(&' + this.name + '_meta, ' + this.parent + ', ' + this.values.length + (this.values.length ? ', ' : '') + this.values.join(', ') + ')';
	if (this.initmsgadded) {
		ret = 'mcall(' + getMethodId('_init') + ', 1, ' + ret + ')'
	}
	return ret;
}

cObject.prototype.toC = function() {
	forwarddec += this.toEarlyCDef();
	toplevelcode += this.toCDef();
	return this.toCInstance();
}

var nextobject = 0;

object.prototype.toC = function() {
	var messages = this.messages;
	var values = [];
	var imports = []
	var me = new cObject('object_' + nextobject++);
	this.symbols.typename = me.name;
	if (this.symbols.needsenv) {
		me.addProperty('env', this.symbols.envVar(), 'struct ' + this.symbols.getEnvType() + ' * ');
		me.hasenv = true;
	}
	if (this.symbols.needsparent && !(this.symbols.parent instanceof osymbols)) {
		me.parent = '(object *)(' + (new symbol('self', this.symbols.parent)).toC() + ')';
	}
	for (var i in messages) {
		if (messages[i] instanceof funcall) {
			if (messages[i].name == 'import:' && messages[i].args.length == 1) {
				imports.push({symbols: false, src: messages[i].args[0]});
			} else if(messages[i].name == 'import:from:' && messages[i].args.length == 2) {
				var importsyms = [];
				each(messages[i].args[0].val, function(i, el) {
					if (!(el instanceof symbol)) {
						throw new Error('Names in import:from statement must be symbols');
					}
					importsyms.push(new strlit(el.name));
				});
				imports.push({symbols: new listlit(importsyms), src: messages[i].args[1]});
			} else {
				throw new Error('Only import and import:from calls allowed in object context');
			}
		} else {
			messages[i].toCObject(me);
		}
	}

	return me.toC();
}

var toplevelcode;
var forwarddec;

function addBinaryOp(cobject, opname, cop, objtype)
{
	cobject.addMessage(opname, {
		vars: {ret: objtype + ' *', argb: objtype +' *'},
		lines: [
			'argb = va_arg(args, ' + objtype + ' *);',
			'ret = (' + objtype + ' *)make_object(&' + objtype + '_meta, NULL, 0);',
			'ret->num = self->num ' + cop + ' argb->num;',
			'return &(ret->header);'
		]
	});
}

function addCompOp(cobject, opname, cop, objtype)
{
	cobject.addMessage(opname, {
		vars: {argb: objtype + ' *'},
		lines: [
			'argb = va_arg(args, ' + objtype + ' *);',
			'if (self->num ' + cop + ' argb->num) {',
			'	return ' + toplevel.moduleVar('true') + ';',
			'}',
			'return ' + toplevel.moduleVar('false') + ';',
		]
	});
}

function makeInt32()
{
	var int32 = new cObject('obj_int32');
	int32.addProperty('num', null, 'int32_t');
	addBinaryOp(int32, 'ADD_', '+', 'obj_int32');
	addBinaryOp(int32, 'SUB_', '-', 'obj_int32');
	addBinaryOp(int32, 'MUL_', '*', 'obj_int32');
	addBinaryOp(int32, 'DIV_', '/', 'obj_int32');
	addBinaryOp(int32, 'MOD_', '%', 'obj_int32');
	addCompOp(int32, 'LT_', '<', 'obj_int32');
	addCompOp(int32, 'GT_', '>', 'obj_int32');
	addCompOp(int32, 'EQ_', '==', 'obj_int32');
	addCompOp(int32, 'NEQ_', '!=', 'obj_int32');
	addCompOp(int32, 'GEQ_', '>=', 'obj_int32');
	addCompOp(int32, 'LEQ_', '<=', 'obj_int32');
	int32.addInclude('<string.h>');
	int32.addMessage('string', {
		vars: {str: 'string *'},
		lines: [
			'str = (string *)make_object(&string_meta, NULL, 0);',
			'str->data = malloc(12);',
			'sprintf(str->data, "%d", self->num);',
			'str->length = str->bytes = strlen(str->data);',
			'return &(str->header);'
		]
	});
	return int32;
}

function makeArray()
{
	var array = new cObject('array');
	array.addProperty('size', null, 'uint32_t');
	array.addProperty('storage', null, 'uint32_t');
	array.addProperty('data', null, 'object **');
	array.addMessage('get', {
		vars: {index: 'obj_int32 *'},
		lines: [
			'index = va_arg(args, obj_int32 *);',
			'if (index->num >= 0 && index->num < self->size) {',
			'	return self->data[index->num];',
			'}',
			'return ' + toplevel.moduleVar('false') + ';'
		]
	});
	array.addMessage('set', {
		vars: {index: 'obj_int32 *'},
		lines: [
			'index = va_arg(args, obj_int32 *);',
			'if (index->num >= 0 && index->num < self->size) {',
			'	self->data[index->num] = va_arg(args, object *);',
			'}',
			'return &(self->header);'
		]
	});
	array.addMessage('foreach', {
		vars: {index: 'obj_int32 *', i: 'int32_t', clos: 'lambda *'},
		lines: [
			'clos = va_arg(args, lambda *);',
			'for (i = 0; i < self->size; i++) {',
			'	index = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'	index->num = i;',
			'	ccall(clos, 2, index, self->data[i]);',
			'}',
			'return &(self->header);'
		]
	});
	array.addMessage('append', {
		vars: {tmp: 'object **'},
		lines: [
			'if (self->storage == self->size) {',
			'	self->storage *= 2;',
			'	tmp = realloc(self->data, self->storage * sizeof(object *));',
			'	if (!tmp) {',
			'		fputs("Failed to increase array size\\n", stderr);',
			'		exit(1);',
			'	}',
			'	self->data = tmp;',
			'}',
			'self->data[self->size++] = va_arg(args, object *);',
			'return &(self->header);'
		]
	});
	array.addMessage('length', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = self->size;',
			'return &(intret->header);'
		]
	});
	return array;
}

function makeString()
{
	var string = new cObject('string');
	string.addProperty('length', null, 'uint32_t');
	string.addProperty('bytes', null, 'uint32_t');
	string.addProperty('data', null, 'char *');
	string.addMessage('length', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = self->length;',
			'return &(intret->header);'
		]
	});
	string.addMessage('byte_length', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = self->bytes;',
			'return &(intret->header);'
		]
	});
	string.addMessage('EQ_', {
		vars: {argb: 'string *'},
		lines: [
			'argb = va_arg(args, string *);',
			'if (self->length == argb->length && self->bytes == argb->bytes && !memcmp(self->data, argb->data, self->bytes)) {',
			'	return ' + toplevel.moduleVar('true') + ';',
			'}',
			'return ' + toplevel.moduleVar('false') + ';',
		]
	});
	string.addMessage('NEQ_', {
		vars: {argb: 'string *'},
		lines: [
			'argb = va_arg(args, string *);',
			'if (self->length != argb->length || self->bytes != argb->bytes || memcmp(self->data, argb->data, self->bytes)) {',
			'	return ' + toplevel.moduleVar('true') + ';',
			'}',
			'return ' + toplevel.moduleVar('false') + ';',
		]
	});
	string.addMessage('print', {
		vars: {},
		lines: [
			'fwrite(self->data, 1, self->bytes, stdout);',
			'return &(self->header);'
		]
	});
	string.addMessage('string', {
		vars: {},
		lines: [ 'return &(self->header);' ]
	});
	string.addMessage('CAT_', {
		vars: {argbo: 'object *', argb: 'string *', out: 'string *'},
		lines: [
			'argbo = va_arg(args, object *);',
			'argb = (string *)mcall(' + getMethodId('string') + ', 1, argbo);',
			'out = (string *)make_object(&string_meta, NULL, 0);',
			'out->bytes = self->bytes + argb->bytes;',
			'out->length = self->length + argb->length;',
			'out->data = malloc(out->bytes+1);',
			'memcpy(out->data, self->data, self->bytes);',
			'memcpy(out->data + self->bytes, argb->data, argb->bytes + 1);',
			'return &(out->header);'
		]
	});
	string.addMessage('byte', {
		vars: {index: 'obj_int32 *', intret: 'obj_int32 *'},
		lines: [
			'index = va_arg(args, obj_int32 *);',
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = index->num < self->bytes ? self->data[index->num] : 0;',
			'return &(intret->header);'
		]
	});
	return string;
}

function makelambda()
{
	var clos = new cObject('lambda');
	clos.addProperty('env', null, 'void *');
	clos.addProperty('func', null, 'closure_func');
	clos.addMessage('while:do', {
		vars: {action: 'lambda *', ret: 'object *'},
		lines: [
			'action = va_arg(args, lambda *);',
			'ret = ' + toplevel.moduleVar('true') + ';',
			'while(' + toplevel.moduleVar('true') + ' == ccall(self, 0)) {',
			'	ccall(action, 0);',
			'}',
			'return ret;'
		]
	});
	return clos;
}

function builtinTypes()
{
	return [makeInt32(), makeArray(), makeString(), makelambda()];
}

function addBuiltinModules(toplevel)
{
	var os = new cObject('mod_obj_os');
	os.addInclude('<sys/stat.h>');
	os.addInclude('<fcntl.h>');
	os.addMessage('write', {
		vars: {str: 'string *', intret: 'obj_int32 *', filedes: 'obj_int32 *'},
		lines: [
			'filedes = va_arg(args, obj_int32 *);',
			'str = va_arg(args, string *);',
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = write(filedes->num, str->data, str->bytes);',
			'return &(intret->header);'
		]
	});
	os.addMessage('read', {
		vars: {str: 'string *', size: 'obj_int32 *', filedes: 'obj_int32 *'},
		lines: [
			'filedes = va_arg(args, obj_int32 *);',
			'size = va_arg(args, obj_int32 *);',
			'str = (string *)make_object(&string_meta, NULL, 0);',
			'str->data = malloc(size->num + 1);',
			'str->length = str->bytes = read(filedes->num, str->data, size->num);',
			'if (str->bytes < 0) { str->bytes = str->length = 0; }',
			'str->data[str->bytes] = 0;',
			'return &(str->header);'
		]
	});
	os.addMessage('open', {
		vars: {str: 'string *', flags: 'obj_int32 *', filedes: 'obj_int32 *', perm: 'obj_int32 *'},
		lines: [
			'str = va_arg(args, string *);',
			'flags = va_arg(args, obj_int32 *);',
			'filedes = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'if (num_params == 3) {',
			'	filedes->num = open(str->data, flags->num);',
			'} else if (num_params == 4) {',
			'	perm = va_arg(args, obj_int32 *);',
			'	filedes->num = open(str->data, flags->num, perm->num);',
			'} else {',
			'	filedes->num = -1;',
			'}',
			'return &(filedes->header);'
		]
	});
	os.addMessage('close', {
		vars: {filedes: 'obj_int32 *', intret: 'obj_int32 *'},
		lines: [
			'filedes = va_arg(args, obj_int32 *);',
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = close(filedes->num);',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_RDONLY', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_RDONLY;',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_WRONLY', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_WRONLY;',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_RDWR', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_RDWR;',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_CREAT', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_CREAT;',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_APPEND', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_APPEND;',
			'return &(intret->header);'
		]
	});
	os.addMessage('O_TRUNC', {
		vars: {intret: 'obj_int32 *'},
		lines: [
			'intret = (obj_int32 *)make_object(&obj_int32_meta, NULL, 0);',
			'intret->num = O_TRUNC;',
			'return &(intret->header);'
		]
	});
	toplevel.names['os'] = os;
}

modulefile.prototype.populateSymbols = function (toplevel) {
	if (!this.ast) {
		this.ast = parseFile(this.path + '/' + this.file);
		this.ast.populateSymbols(toplevel);
	}
};

modulefile.prototype.toC = function(){
	this.populateSymbols(toplevel);
	return this.ast.toCModuleInstance();
};

function processUsedToplevel(toplevel)
{	
	var alwaysused = ['true', 'false'];
	var ret = '';
	var modulenum = 0;
	var newused = Object.keys(toplevel.used);
	var allused = newused;
	var visited = {};
	for (var i in alwaysused) {
		forwarddec += 'object * ' + toplevel.moduleVar(alwaysused[i]) + ';\n';
		toplevel.names[alwaysused[i]].populateSymbols(toplevel);
		visited[alwaysused[i]] = true;
	}
	while (newused.length) {
		for (var i in newused) {
			debugprint('//---module', newused[i], '--- populate symbols');
			forwarddec += 'object * ' + toplevel.moduleVar(newused[i]) + ';\n';
			toplevel.names[newused[i]].populateSymbols(toplevel);
			visited[newused[i]] = true;
		}
		newused = [];
		for (var symbol in toplevel.used) {
			if (!(symbol in visited)) {
				debugprint('//found new usage of module', symbol);
				newused.push(symbol);
				allused.push(symbol);
			}
		}
	}
	for (var i in alwaysused) {
		allused.push(alwaysused[i]);
	}
		
	for (var i = allused.length-1; i >= 0; i--) {
		var symbol = allused[i];
		debugprint('//---module', symbol, '--- compile');
		ret += '\t' + toplevel.moduleVar(symbol) + ' = ' + toplevel.names[symbol].toC() + ';\n';
	}
	return ret;
}

function makeCProg(obj)
{
	var builtins = builtinTypes();
	forwarddec = toplevelcode = '';
	for (var i in builtins) {
		forwarddec += builtins[i].toEarlyCDef();
		toplevelcode += builtins[i].toCDef();
	}
	addBuiltinModules(toplevel);
	debugprint('//------POPULATING SYMBOLS-----');
	obj.populateSymbols(toplevel);
	var moduleinit = processUsedToplevel(toplevel);
	debugprint('//------COMPILING AST-----');
	var rest = 'object * mainModule() {\n' + moduleinit + '\tmain_module = ' + obj.toCModuleInstance() + ';\n\treturn main_module;\n}\n';
	return '#include "runtime/proghead.inc"\n' +
		'#define METHOD_ID_MAIN ' + getMethodId('main') + '\n' +
		forwarddec + toplevelcode + rest + '#include "runtime/progfoot.inc"\n';
}

object.prototype.toCModule = function() {
	return makeCProg(this);
}

object.prototype.toCModuleInstance = function() {
	return this.toC();
}

var lambdanum = 0;

lambda.prototype.toC = function() {
	var args = this.args ? this.args.slice(0, this.args.length) : [];
	var exprs = this.expressions;
	var mynum = lambdanum++;
	debugprint('//lambda', mynum);
	if (Object.keys(this.symbols.closedover).length) {
		this.symbols.envtype = 'lambda_' + mynum + '_env';
	}
	if (this.selftype) {
		this.symbols.defineVar('self', this.selftype);
		if (args[0] && args[0].cleanName() == 'self') {
			args.splice(0, 1);
		}
		var offset = 1;
	} else {
		var offset = 0;
	}
	for (var i = 0; i < args.length; ++i) {
		var argname = args[i].toC();
		
		args[i] = (argname.indexOf('->') < 0 ? '\tobject * ' : '\t') + argname + ' = va_arg(args, object *);\n';
	}
	var compiled = []
	for (var i in exprs) {
		var js = exprs[i].toC();
		if (js) {
			compiled.push(indent(js));
		}
	}
	exprs = compiled;
	if (exprs.length) {
		exprs[exprs.length-1] = 'return ' + exprs[exprs.length-1] + ';';
	}
	
	if (Object.keys(this.symbols.closedover).length) {
		forwarddec += 'typedef struct lambda_' + mynum + '_env {\n';
		if (this.symbols.needsParentEnv) {
			forwarddec += '\tstruct ' + this.symbols.parentEnvType() + ' * parent;\n';
		}
		for (var varname in this.symbols.closedover) {
			if (varname == 'self' && this.selftype) {
				forwarddec += '\tstruct ' + this.selftype + ' * self;\n';
			} else {
				forwarddec += '\tobject * ' + escapeCName(varname) + ';\n';
			}
		}
		forwarddec += '} lambda_' + mynum + '_env;\n'
		
		var myenvinit = '\tlambda_' + mynum + '_env * myenv = malloc(sizeof(lambda_' + mynum + '_env));\n';
		if (this.symbols.needsParentEnv) {
			myenvinit += '\tmyenv->parent = env;\n';
		}
		this.symbols.envtype = 'lambda_' + mynum + '_env';
	} else {
		var myenvinit = '';
	}
	
	toplevelcode +=  'object * lambda_' + mynum + ' (' + this.symbols.parentEnvType() + ' * env, uint32_t num_args, ...) {\n\tva_list args;\n' + myenvinit + '\tva_start(args, num_args);\n';
	if (this.selftype) {
		var selfvar = (new symbol('self', this.symbols)).toC();
		if (selfvar == 'self') {
			toplevelcode += '\t' + this.selftype + ' * self = va_arg(args, ' + this.selftype + ' *);\n';
		} else {
			toplevelcode += '\t' + selfvar  + ' = va_arg(args, ' + this.selftype + ' *);\n';
		}
		
	}
	toplevelcode += args.join('') + '\tva_end(args);\n' + exprs.join(';\n\t') + '\n}\n';
	this.name = 'lambda_' + mynum;
	
	if (this.selftype) {
		return this.name;
	} else {
		if (this.symbols.parentEnvType() != 'void') {
			if (this.symbols.parent.passthruenv) {
				var envvar = 'env';
			} else {
				var envvar = 'myenv';
			}
			debugprint('//lambda_' + mynum, 'has envvar:', envvar, 'num vars closed over:', Object.keys(this.symbols.closedover).length);
			return 'make_lambda(' + envvar + ', (closure_func)' + this.name + ')';
		} else {	
			toplevelcode += 'lambda lambda_obj_' + mynum + ' = {{&lambda_meta, NULL}, NULL, lambda_' + mynum + '};\n';
			return '((object *)&lambda_obj_' + mynum + ')';
		}
	}
};
lambda.prototype.toCModuleInstance = function() {
	this.toC();
	return this.name + '(NULL, 0)';
};
lambda.prototype.toCObject = function(typename) {
	this.selftype = typename;
	return this.toC();
};
lambda.prototype.toCModule = function() {
	return makeCProg(this);
}

assignment.prototype.toC = function() {
	debugprint('//assignment', this.symbol.name);
	var existing = this.symbols.find(this.symbol.name);
	var prefix = '';
	var val = this.expression.toC();
	if (val === null) {
		return null;
	}
	if (existing.type == 'local' && !existing.isdeclared) {
		prefix = 'object *';
		this.symbols.declareVar(this.symbol.name);
		debugprint('//declared var', this.symbol.name);
	}
	return prefix + this.symbol.toC() + ' = ' + val;
};
assignment.prototype.toCObject = function(cobj) {
	debugprint('//message definition', this.symbol.name);
	if (this.expression.toCObject) {
		var val = this.expression.toCObject(cobj.name);
	} else {
		var val = this.expression.toC();
	}
	if (val === null) {
		return;
	}
	if (this.expression instanceof lambda) {
		var params = ['((object *)self)'];
		var paramget = '';
		var messagevars = {};
		for (var i in this.expression.args) {
			var escaped = escapeCName(this.expression.args[i].cleanName());
			if (escaped != 'self') {
				messagevars[escaped] = 'object *';
				params.push(escaped);
				paramget += escaped + ' =  va_arg(args, object *); ';
			}
		}
		cobj.addMessage(this.symbol.name, {
			vars: messagevars,
			lines: [paramget + 'return ' + val + '(' + (cobj.hasenv ? 'self->env' : 'NULL') + ', ' + params.length + (params.length ? ', ' : '') + params.join(', ') + ');']
		});
	} else {
		cobj.addProperty(this.symbol.name, val);
		if (this.expression instanceof object && this.expression.symbols.needsparent) {
			cobj.addInit('self->' + escapeCName(this.symbol.name) + '->parent = self;');
		}
	}
};