/*
 *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
 *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include "config.h"
#include "FunctionConstructor.h"

#include "FunctionPrototype.h"
#include "JSFunction.h"
#include "JSGlobalObject.h"
#include "JSString.h"
#include "Parser.h"
#include "Debugger.h"
#include "lexer.h"
#include "nodes.h"

namespace JSC {

ASSERT_CLASS_FITS_IN_CELL(FunctionConstructor);

FunctionConstructor::FunctionConstructor(ExecState* exec, PassRefPtr<StructureID> structure, FunctionPrototype* functionPrototype)
    : InternalFunction(&exec->globalData(), structure, Identifier(exec, functionPrototype->classInfo()->className))
{
    putDirectWithoutTransition(exec->propertyNames().prototype, functionPrototype, DontEnum | DontDelete | ReadOnly);

    // Number of arguments for constructor
    putDirectWithoutTransition(exec->propertyNames().length, jsNumber(exec, 1), ReadOnly | DontDelete | DontEnum);
}

static JSObject* constructWithFunctionConstructor(ExecState* exec, JSObject*, const ArgList& args)
{
    return constructFunction(exec, args);
}

ConstructType FunctionConstructor::getConstructData(ConstructData& constructData)
{
    constructData.native.function = constructWithFunctionConstructor;
    return ConstructTypeHost;
}

static JSValue* callFunctionConstructor(ExecState* exec, JSObject*, JSValue*, const ArgList& args)
{
    return constructFunction(exec, args);
}

// ECMA 15.3.1 The Function Constructor Called as a Function
CallType FunctionConstructor::getCallData(CallData& callData)
{
    callData.native.function = callFunctionConstructor;
    return CallTypeHost;
}

// ECMA 15.3.2 The Function Constructor
JSObject* constructFunction(ExecState* exec, const ArgList& args, const Identifier& functionName, const UString& sourceURL, int lineNumber)
{
    UString p("");
    UString body;
    int argsSize = args.size();
    if (argsSize == 0)
        body = "";
    else if (argsSize == 1)
        body = args.at(exec, 0)->toString(exec);
    else {
        p = args.at(exec, 0)->toString(exec);
        for (int k = 1; k < argsSize - 1; k++)
            p += "," + args.at(exec, k)->toString(exec);
        body = args.at(exec, argsSize - 1)->toString(exec);
    }

    // parse the source code
    int errLine;
    UString errMsg;
    SourceCode source = makeSource(body, sourceURL, lineNumber);
    RefPtr<FunctionBodyNode> functionBody = exec->globalData().parser->parse<FunctionBodyNode>(exec, exec->dynamicGlobalObject()->debugger(), source, &errLine, &errMsg);

    // No program node == syntax error - throw a syntax error
    if (!functionBody)
        // We can't return a Completion(Throw) here, so just set the exception
        // and return it
        return throwError(exec, SyntaxError, errMsg, errLine, source.provider()->asID(), source.provider()->url());

    // parse parameter list. throw syntax error on illegal identifiers
    int len = p.size();
    const UChar* c = p.data();
    int i = 0;
    UString param;
    Vector<Identifier> parameters;
    while (i < len) {
        while (*c == ' ' && i < len)
            c++, i++;
        if (Lexer::isIdentStart(c[0])) {  // else error
            param = UString(c, 1);
            c++, i++;
            while (i < len && (Lexer::isIdentPart(c[0]))) {
                param.append(*c);
                c++, i++;
            }
            while (i < len && *c == ' ')
                c++, i++;
            if (i == len) {
                parameters.append(Identifier(exec, param));
                break;
            } else if (*c == ',') {
                parameters.append(Identifier(exec, param));
                c++, i++;
                continue;
            } // else error
        }
        return throwError(exec, SyntaxError, "Syntax error in parameter list");
    }
    size_t count = parameters.size();
    functionBody->finishParsing(parameters.releaseBuffer(), count);

    JSGlobalObject* globalObject = exec->lexicalGlobalObject();
    ScopeChain scopeChain(globalObject, globalObject->globalData(), exec->globalThisValue());
    JSFunction* function = new (exec) JSFunction(exec, functionName, functionBody.get(), scopeChain.node());

    JSObject* prototype = constructEmptyObject(exec);
    prototype->putDirect(exec->propertyNames().constructor, function, DontEnum);
    function->putDirect(exec->propertyNames().prototype, prototype, DontDelete);
    return function;
}

// ECMA 15.3.2 The Function Constructor
JSObject* constructFunction(ExecState* exec, const ArgList& args)
{
    return constructFunction(exec, args, Identifier(exec, "anonymous"), UString(), 1);
}

} // namespace JSC