/*
 * Copyright (C) 2021 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “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 HOLDER 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
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 */

#include "config.h"
#include "CSSStyleValueFactory.h"

#if ENABLE(CSS_TYPED_OM)

#include "CSSCustomPropertyValue.h"
#include "CSSKeywordValue.h"
#include "CSSNumericFactory.h"
#include "CSSParser.h"
#include "CSSPendingSubstitutionValue.h"
#include "CSSPropertyParser.h"
#include "CSSStyleImageValue.h"
#include "CSSStyleValue.h"
#include "CSSUnitValue.h"
#include "CSSUnparsedValue.h"
#include "CSSValueList.h"
#include "CSSVariableData.h"
#include "CSSVariableReferenceValue.h"
#include "StylePropertyShorthand.h"
#include <wtf/IsoMallocInlines.h>
#include <wtf/NeverDestroyed.h>
#include <wtf/text/StringBuilder.h>
#include <wtf/text/StringView.h>

namespace WebCore {

ExceptionOr<void> CSSStyleValueFactory::extractCSSValues(Vector<Ref<CSSValue>>& cssValues, const CSSPropertyID& propertyID, const String& cssText)
{
    auto styleDeclaration = MutableStyleProperties::create();
    
    constexpr bool important = true;
    CSSParser::ParseResult parseResult = CSSParser::parseValue(styleDeclaration, propertyID, cssText, important, strictCSSParserContext());

    if (parseResult == CSSParser::ParseResult::Error)
        return Exception { TypeError, makeString(cssText, " cannot be parsed.")};

    if (auto cssValue = styleDeclaration->getPropertyCSSValue(propertyID))
        cssValues.append(cssValue.releaseNonNull());
    
    return { };
}

ExceptionOr<void> CSSStyleValueFactory::extractShorthandCSSValues(Vector<Ref<CSSValue>>& cssValues, const CSSPropertyID& propertyID, const String& cssText)
{
    auto styleDeclaration = MutableStyleProperties::create();

    constexpr bool important = true;
    CSSParser::ParseResult parseResult = CSSParser::parseValue(styleDeclaration, propertyID, cssText, important, strictCSSParserContext());

    if (parseResult == CSSParser::ParseResult::Error)
        return Exception { TypeError, makeString(cssText, " cannot be parsed.")};

    auto shorthand = shorthandForProperty(propertyID);
    for (auto longhand : shorthand) {
        if (auto cssValue = styleDeclaration->getPropertyCSSValue(longhand))
            cssValues.append(cssValue.releaseNonNull());
    }
    return { };
}

ExceptionOr<void> CSSStyleValueFactory::extractCustomCSSValues(Vector<Ref<CSSValue>>& cssValues, const String& customPropertyName, const String& cssText)
{
    auto styleDeclaration = MutableStyleProperties::create();
    
    constexpr bool important = true;
    CSSParser::ParseResult parseResult = CSSParser::parseCustomPropertyValue(styleDeclaration, customPropertyName, cssText, important, strictCSSParserContext());
    
    if (parseResult == CSSParser::ParseResult::Error)
        return Exception { TypeError, makeString(cssText, " cannot be parsed.")};
    
    if (auto customValue = styleDeclaration->getPropertyCSSValue(CSSPropertyCustom))
        cssValues.append(customValue.releaseNonNull());
    
    return { };
}

ExceptionOr<Vector<Ref<CSSStyleValue>>> CSSStyleValueFactory::parseStyleValue(const String& cssProperty, const String& cssText, bool parseMultiple)
{
    // https://www.w3.org/TR/css-typed-om-1/#cssstylevalue
    
    Vector<Ref<CSSValue>> cssValues;
    
    // Extract the CSSValue from cssText given cssProperty
    if (isCustomPropertyName(cssProperty)) {
        auto result = extractCustomCSSValues(cssValues, cssProperty, cssText);
        if (result.hasException())
            return result.releaseException();
    } else {
        String property = cssProperty.convertToASCIILowercase();
        
        auto propertyID = cssPropertyID(property);

        if (propertyID == CSSPropertyInvalid)
            return Exception { TypeError, "Property String is not a valid CSS property."_s };
        
        
        if (isShorthandCSSProperty(propertyID)) {
            auto result = extractShorthandCSSValues(cssValues, propertyID, cssText);
            if (result.hasException())
                return result.releaseException();
        } else {
            auto result = extractCSSValues(cssValues, propertyID, cssText);
            if (result.hasException())
                return result.releaseException();
        }
    }

    Vector<Ref<CSSStyleValue>> results;

    for (auto& cssValue : cssValues) {
        auto reifiedValue = reifyValue(WTFMove(cssValue));
        if (reifiedValue.hasException())
            return reifiedValue.releaseException();

        results.append(reifiedValue.releaseReturnValue());
        
        if (!parseMultiple)
            break;
    }
    
    return results;
}

ExceptionOr<Ref<CSSStyleValue>> CSSStyleValueFactory::reifyValue(Ref<CSSValue>&& cssValue, Document* document)
{
    if (is<CSSPrimitiveValue>(cssValue)) {
        auto primitiveValue = downcast<CSSPrimitiveValue>(cssValue.ptr());
        switch (primitiveValue->primitiveType()) {
        case CSSUnitType::CSS_NUMBER:
            return Ref<CSSStyleValue> { CSSNumericFactory::number(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_PERCENTAGE:
            return Ref<CSSStyleValue> { CSSNumericFactory::percent(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_EMS:
            return Ref<CSSStyleValue> { CSSNumericFactory::em(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_EXS:
            return Ref<CSSStyleValue> { CSSNumericFactory::ex(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_CHS:
            return Ref<CSSStyleValue> { CSSNumericFactory::ch(primitiveValue->doubleValue()) };
        // FIXME: Add CSSNumericFactory::ic
        case CSSUnitType::CSS_REMS:
            return Ref<CSSStyleValue> { CSSNumericFactory::rem(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_LHS:
            return Ref<CSSStyleValue> { CSSNumericFactory::lh(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_RLHS:
            return Ref<CSSStyleValue> { CSSNumericFactory::rlh(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_VW:
            return Ref<CSSStyleValue> { CSSNumericFactory::vw(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_VH:
            return Ref<CSSStyleValue> { CSSNumericFactory::vh(primitiveValue->doubleValue()) };
        // FIXME: Add CSSNumericFactory::vi & ::vb
        case CSSUnitType::CSS_VMIN:
            return Ref<CSSStyleValue> { CSSNumericFactory::vmin(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_VMAX:
            return Ref<CSSStyleValue> { CSSNumericFactory::vmax(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_CM:
            return Ref<CSSStyleValue> { CSSNumericFactory::cm(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_MM:
            return Ref<CSSStyleValue> { CSSNumericFactory::mm(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_Q:
            return Ref<CSSStyleValue> { CSSNumericFactory::q(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_IN:
            return Ref<CSSStyleValue> { CSSNumericFactory::in(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_PT:
            return Ref<CSSStyleValue> { CSSNumericFactory::pt(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_PC:
            return Ref<CSSStyleValue> { CSSNumericFactory::pc(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_PX:
            return Ref<CSSStyleValue> { CSSNumericFactory::px(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_DEG:
            return Ref<CSSStyleValue> { CSSNumericFactory::deg(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_GRAD:
            return Ref<CSSStyleValue> { CSSNumericFactory::grad(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_RAD:
            return Ref<CSSStyleValue> { CSSNumericFactory::rad(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_TURN:
            return Ref<CSSStyleValue> { CSSNumericFactory::turn(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_S:
            return Ref<CSSStyleValue> { CSSNumericFactory::s(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_MS:
            return Ref<CSSStyleValue> { CSSNumericFactory::ms(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_HZ:
            return Ref<CSSStyleValue> { CSSNumericFactory::hz(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_KHZ:
            return Ref<CSSStyleValue> { CSSNumericFactory::kHz(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_DPI:
            return Ref<CSSStyleValue> { CSSNumericFactory::dpi(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_DPCM:
            return Ref<CSSStyleValue> { CSSNumericFactory::dpcm(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_DPPX:
            return Ref<CSSStyleValue> { CSSNumericFactory::dppx(primitiveValue->doubleValue()) };
        case CSSUnitType::CSS_FR:
            return Ref<CSSStyleValue> { CSSNumericFactory::fr(primitiveValue->doubleValue()) };
        
        case CSSUnitType::CSS_STRING: {
            auto value = CSSKeywordValue::create(primitiveValue->stringValue());
            if (value.hasException())
                return value.releaseException();
            
            return Ref<CSSStyleValue> { value.releaseReturnValue() };
        }
        default:
            break;
        }
    } else if (is<CSSImageValue>(cssValue))
        return Ref<CSSStyleValue> { CSSStyleImageValue::create(downcast<CSSImageValue>(cssValue.get()), document) };
    else if (is<CSSVariableReferenceValue>(cssValue)) {
        return Ref<CSSStyleValue> { CSSUnparsedValue::create(downcast<CSSVariableReferenceValue>(cssValue.get()).data().tokenRange()) };
    } else if (is<CSSPendingSubstitutionValue>(cssValue)) {
        return Ref<CSSStyleValue> { CSSUnparsedValue::create(downcast<CSSPendingSubstitutionValue>(cssValue.get()).shorthandValue().data().tokenRange()) };
    } else if (is<CSSCustomPropertyValue>(cssValue)) {
        // FIXME: remove CSSStyleValue::create(WTFMove(cssValue)), add reification control flow
        return WTF::switchOn(downcast<CSSCustomPropertyValue>(cssValue.get()).value(), [&](const Ref<CSSVariableReferenceValue>& value) {
            return reifyValue(value.copyRef(), document);
        }, [&](Ref<CSSVariableData>& value) {
            return reifyValue(CSSVariableReferenceValue::create(WTFMove(value)));
        }, [&](auto&) {
            // FIXME: Property reify the other cases.
            return ExceptionOr<Ref<CSSStyleValue>> { CSSStyleValue::create(WTFMove(cssValue)) };
        });
    } else if (is<CSSValueList>(cssValue)) {
        // Reifying the first value in value list.
        // FIXME: Verify this is the expected behavior.
        // Refer to LayoutTests/imported/w3c/web-platform-tests/css/css-typed-om/the-stylepropertymap/inline/get.html
        auto valueList = downcast<CSSValueList>(cssValue.ptr());
        if (!valueList->length())
            return Exception { TypeError, "The CSSValueList should not be empty." };
        
        return reifyValue(WTFMove(*valueList->begin()), document);
    }
    
    return CSSStyleValue::create(WTFMove(cssValue));
}

} // namespace WebCore

#endif