/*

 *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org)

 *  Copyright (C) 2001 Peter Kelly (pmk@post.com)

 *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.

 *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)

 *  Copyright (C) 2007 Maks Orlovich

 *

 *  This library is free software; you can redistribute it and/or

 *  modify it under the terms of the GNU Library 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

 *  Library General Public License for more details.

 *

 *  You should have received a copy of the GNU Library General Public License

 *  along with this library; see the file COPYING.LIB.  If not, write to

 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 *  Boston, MA 02110-1301, USA.

 *

 */

#include "config.h"

#include "JSGlobalObjectFunctions.h"

#include "CallFrame.h"

#include "GlobalEvalFunction.h"

#include "Interpreter.h"

#include "JSGlobalObject.h"

#include "JSString.h"

#include "JSStringBuilder.h"

#include "Lexer.h"

#include "LiteralParser.h"

#include "Nodes.h"

#include "Parser.h"

#include "StringBuilder.h"

#include "dtoa.h"

#include <stdio.h>

#include <stdlib.h>

#include <wtf/ASCIICType.h>

#include <wtf/Assertions.h>

#include <wtf/MathExtras.h>

#include <wtf/StringExtras.h>

#include <wtf/unicode/UTF8.h>

using namespace WTF;

using namespace Unicode;

namespace JSC {

static JSValue encode(ExecState* exec, const char* doNotEscape)

{

    UString str = exec->argument(0).toString(exec);

    CString cstr = str.UTF8String(true);

    if (!cstr.data())

        return throwError(exec, createURIError(exec, "String contained an illegal UTF-16 sequence."));

    JSStringBuilder builder;

    const char* p = cstr.data();

    for (size_t k = 0; k < cstr.length(); k++, p++) {

        char c = *p;

        if (c && strchr(doNotEscape, c))

            builder.append(c);

        else {

            char tmp[4];

            snprintf(tmp, sizeof(tmp), "%%%02X", static_cast<unsigned char>(c));

            builder.append(tmp);

        }

    }

    return builder.build(exec);

}

static JSValue decode(ExecState* exec, const char* doNotUnescape, bool strict)

{

    JSStringBuilder builder;

    UString str = exec->argument(0).toString(exec);

    int k = 0;

    int len = str.size();

    const UChar* d = str.data();

    UChar u = 0;

    while (k < len) {

        const UChar* p = d + k;

        UChar c = *p;

        if (c == '%') {

            int charLen = 0;

            if (k <= len - 3 && isASCIIHexDigit(p[1]) && isASCIIHexDigit(p[2])) {

                const char b0 = Lexer::convertHex(p[1], p[2]);

                const int sequenceLen = UTF8SequenceLength(b0);

                if (sequenceLen != 0 && k <= len - sequenceLen * 3) {

                    charLen = sequenceLen * 3;

                    char sequence[5];

                    sequence[0] = b0;

                    for (int i = 1; i < sequenceLen; ++i) {

                        const UChar* q = p + i * 3;

                        if (q[0] == '%' && isASCIIHexDigit(q[1]) && isASCIIHexDigit(q[2]))

                            sequence[i] = Lexer::convertHex(q[1], q[2]);

                        else {

                            charLen = 0;

                            break;

                        }

                    }

                    if (charLen != 0) {

                        sequence[sequenceLen] = 0;

                        const int character = decodeUTF8Sequence(sequence);

                        if (character < 0 || character >= 0x110000)

                            charLen = 0;

                        else if (character >= 0x10000) {

                            // Convert to surrogate pair.

                            builder.append(static_cast<UChar>(0xD800 | ((character - 0x10000) >> 10)));

                            u = static_cast<UChar>(0xDC00 | ((character - 0x10000) & 0x3FF));

                        } else

                            u = static_cast<UChar>(character);

                    }

                }

            }

            if (charLen == 0) {

                if (strict)

                    return throwError(exec, createURIError(exec, "URI error"));

                // The only case where we don't use "strict" mode is the "unescape" function.

                // For that, it's good to support the wonky "%u" syntax for compatibility with WinIE.

                if (k <= len - 6 && p[1] == 'u'

                        && isASCIIHexDigit(p[2]) && isASCIIHexDigit(p[3])

                        && isASCIIHexDigit(p[4]) && isASCIIHexDigit(p[5])) {

                    charLen = 6;

                    u = Lexer::convertUnicode(p[2], p[3], p[4], p[5]);

                }

            }

            if (charLen && (u == 0 || u >= 128 || !strchr(doNotUnescape, u))) {

                c = u;

                k += charLen - 1;

            }

        }

        k++;

        builder.append(c);

    }

    return builder.build(exec);

}

bool isStrWhiteSpace(UChar c)

{

    switch (c) {

        // ECMA-262-5th 7.2 & 7.3

        case 0x0009:

        case 0x000A:

        case 0x000B:

        case 0x000C:

        case 0x000D:

        case 0x0020:

        case 0x00A0:

        case 0x2028:

        case 0x2029:

        case 0xFEFF:

            return true;

        default:

            return c > 0xff && isSeparatorSpace(c);

    }

}

static int parseDigit(unsigned short c, int radix)

{

    int digit = -1;

    if (c >= '0' && c <= '9')

        digit = c - '0';

    else if (c >= 'A' && c <= 'Z')

        digit = c - 'A' + 10;

    else if (c >= 'a' && c <= 'z')

        digit = c - 'a' + 10;

    if (digit >= radix)

        return -1;

    return digit;

}

double parseIntOverflow(const char* s, int length, int radix)

{

    double number = 0.0;

    double radixMultiplier = 1.0;

    for (const char* p = s + length - 1; p >= s; p--) {

        if (radixMultiplier == Inf) {

            if (*p != '0') {

                number = Inf;

                break;

            }

        } else {

            int digit = parseDigit(*p, radix);

            number += digit * radixMultiplier;

        }

        radixMultiplier *= radix;

    }

    return number;

}

double parseIntOverflow(const UChar* s, int length, int radix)

{

    double number = 0.0;

    double radixMultiplier = 1.0;

    for (const UChar* p = s + length - 1; p >= s; p--) {

        if (radixMultiplier == Inf) {

            if (*p != '0') {

                number = Inf;

                break;

            }

        } else {

            int digit = parseDigit(*p, radix);

            number += digit * radixMultiplier;

        }

        radixMultiplier *= radix;

    }

    return number;

}

static double parseInt(const UString& s, int radix)

{

    int length = s.size();

    const UChar* data = s.data();

    int p = 0;

    while (p < length && isStrWhiteSpace(data[p]))

        ++p;

    double sign = 1;

    if (p < length) {

        if (data[p] == '+')

            ++p;

        else if (data[p] == '-') {

            sign = -1;

            ++p;

        }

    }

    if ((radix == 0 || radix == 16) && length - p >= 2 && data[p] == '0' && (data[p + 1] == 'x' || data[p + 1] == 'X')) {

        radix = 16;

        p += 2;

    } else if (radix == 0) {

        if (p < length && data[p] == '0')

            radix = 8;

        else

            radix = 10;

    }

    if (radix < 2 || radix > 36)

        return NaN;

    int firstDigitPosition = p;

    bool sawDigit = false;

    double number = 0;

    while (p < length) {

        int digit = parseDigit(data[p], radix);

        if (digit == -1)

            break;

        sawDigit = true;

        number *= radix;

        number += digit;

        ++p;

    }

    if (number >= mantissaOverflowLowerBound) {

        if (radix == 10)

            number = WTF::strtod(s.substr(firstDigitPosition, p - firstDigitPosition).UTF8String().data(), 0);

        else if (radix == 2 || radix == 4 || radix == 8 || radix == 16 || radix == 32)

            number = parseIntOverflow(s.substr(firstDigitPosition, p - firstDigitPosition).UTF8String().data(), p - firstDigitPosition, radix);

    }

    if (!sawDigit)

        return NaN;

    return sign * number;

}

static double parseFloat(const UString& s)

{

    // Check for 0x prefix here, because toDouble allows it, but we must treat it as 0.

    // Need to skip any whitespace and then one + or - sign.

    int length = s.size();

    const UChar* data = s.data();

    int p = 0;

    while (p < length && isStrWhiteSpace(data[p]))

        ++p;

    if (p < length && (data[p] == '+' || data[p] == '-'))

        ++p;

    if (length - p >= 2 && data[p] == '0' && (data[p + 1] == 'x' || data[p + 1] == 'X'))

        return 0;

    return s.toDouble(true /*tolerant*/, false /* NaN for empty string */);

}

EncodedJSValue JSC_HOST_CALL globalFuncEval(ExecState* exec)

{

    JSObject* thisObject = exec->hostThisValue().toThisObject(exec);

    JSObject* unwrappedObject = thisObject->unwrappedObject();

    if (!unwrappedObject->isGlobalObject() || static_cast<JSGlobalObject*>(unwrappedObject)->evalFunction() != exec->callee())

        return throwVMError(exec, createEvalError(exec, "The \"this\" value passed to eval must be the global object from which eval originated"));

    JSValue x = exec->argument(0);

    if (!x.isString())

        return JSValue::encode(x);

    UString s = x.toString(exec);

    LiteralParser preparser(exec, s, LiteralParser::NonStrictJSON);

    if (JSValue parsedObject = preparser.tryLiteralParse())

        return JSValue::encode(parsedObject);

    RefPtr<EvalExecutable> eval = EvalExecutable::create(exec, makeSource(s));

    JSObject* error = eval->compile(exec, static_cast<JSGlobalObject*>(unwrappedObject)->globalScopeChain().node());

    if (error)

        return throwVMError(exec, error);

    return JSValue::encode(exec->interpreter()->execute(eval.get(), exec, thisObject, static_cast<JSGlobalObject*>(unwrappedObject)->globalScopeChain().node(), exec->exceptionSlot()));

}

EncodedJSValue JSC_HOST_CALL globalFuncParseInt(ExecState* exec)

{

    JSValue value = exec->argument(0);

    int32_t radix = exec->argument(1).toInt32(exec);

    if (radix != 0 && radix != 10)

        return JSValue::encode(jsNumber(exec, parseInt(value.toString(exec), radix)));

    if (value.isInt32())

        return JSValue::encode(value);

    if (value.isDouble()) {

        double d = value.asDouble();

        if (isfinite(d))

            return JSValue::encode(jsNumber(exec, (d > 0) ? floor(d) : ceil(d)));

        if (isnan(d) || isinf(d))

            return JSValue::encode(jsNaN(exec));

        return JSValue::encode(jsNumber(exec, 0));

    }

    return JSValue::encode(jsNumber(exec, parseInt(value.toString(exec), radix)));

}

EncodedJSValue JSC_HOST_CALL globalFuncParseFloat(ExecState* exec)

{

    return JSValue::encode(jsNumber(exec, parseFloat(exec->argument(0).toString(exec))));

}

EncodedJSValue JSC_HOST_CALL globalFuncIsNaN(ExecState* exec)

{

    return JSValue::encode(jsBoolean(isnan(exec->argument(0).toNumber(exec))));

}

EncodedJSValue JSC_HOST_CALL globalFuncIsFinite(ExecState* exec)

{

    double n = exec->argument(0).toNumber(exec);

    return JSValue::encode(jsBoolean(!isnan(n) && !isinf(n)));

}

EncodedJSValue JSC_HOST_CALL globalFuncDecodeURI(ExecState* exec)

{

    static const char do_not_unescape_when_decoding_URI[] =

        "#$&+,/:;=?@";

    return JSValue::encode(decode(exec, do_not_unescape_when_decoding_URI, true));

}

EncodedJSValue JSC_HOST_CALL globalFuncDecodeURIComponent(ExecState* exec)

{

    return JSValue::encode(decode(exec, "", true));

}

EncodedJSValue JSC_HOST_CALL globalFuncEncodeURI(ExecState* exec)

{

    static const char do_not_escape_when_encoding_URI[] =

        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

        "abcdefghijklmnopqrstuvwxyz"

        "0123456789"

        "!#$&'()*+,-./:;=?@_~";

    return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI));

}

EncodedJSValue JSC_HOST_CALL globalFuncEncodeURIComponent(ExecState* exec)

{

    static const char do_not_escape_when_encoding_URI_component[] =

        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

        "abcdefghijklmnopqrstuvwxyz"

        "0123456789"

        "!'()*-._~";

    return JSValue::encode(encode(exec, do_not_escape_when_encoding_URI_component));

}

EncodedJSValue JSC_HOST_CALL globalFuncEscape(ExecState* exec)

{

    static const char do_not_escape[] =

        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

        "abcdefghijklmnopqrstuvwxyz"

        "0123456789"

        "*+-./@_";

    JSStringBuilder builder;

    UString str = exec->argument(0).toString(exec);

    const UChar* c = str.data();

    for (unsigned k = 0; k < str.size(); k++, c++) {

        int u = c[0];

        if (u > 255) {

            char tmp[7];

            snprintf(tmp, sizeof(tmp), "%%u%04X", u);

            builder.append(tmp);

        } else if (u != 0 && strchr(do_not_escape, static_cast<char>(u)))

            builder.append(c, 1);

        else {

            char tmp[4];

            snprintf(tmp, sizeof(tmp), "%%%02X", u);

            builder.append(tmp);

        }

    }

    return JSValue::encode(builder.build(exec));

}

EncodedJSValue JSC_HOST_CALL globalFuncUnescape(ExecState* exec)

{

    StringBuilder builder;

    UString str = exec->argument(0).toString(exec);

    int k = 0;

    int len = str.size();

    while (k < len) {

        const UChar* c = str.data() + k;

        UChar u;

        if (c[0] == '%' && k <= len - 6 && c[1] == 'u') {

            if (isASCIIHexDigit(c[2]) && isASCIIHexDigit(c[3]) && isASCIIHexDigit(c[4]) && isASCIIHexDigit(c[5])) {

                u = Lexer::convertUnicode(c[2], c[3], c[4], c[5]);

                c = &u;

                k += 5;

            }

        } else if (c[0] == '%' && k <= len - 3 && isASCIIHexDigit(c[1]) && isASCIIHexDigit(c[2])) {

            u = UChar(Lexer::convertHex(c[1], c[2]));

            c = &u;

            k += 2;

        }

        k++;

        builder.append(*c);

    }

    return JSValue::encode(jsString(exec, builder.build()));

}

#ifndef NDEBUG

EncodedJSValue JSC_HOST_CALL globalFuncJSCPrint(ExecState* exec)

{

    CString string = exec->argument(0).toString(exec).UTF8String();

    puts(string.data());

    return JSValue::encode(jsUndefined());

}

#endif

} // namespace JSC