/****************************************************************************
 Copyright (c) 2013      Zynga Inc.
 Copyright (c) 2013-2016 Chukong Technologies Inc.
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.

 https://axmolengine.github.io/

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/

#include "2d/Label.h"
#include <vector>
#include "base/UTF8.h"
#include "base/Director.h"
#include "2d/FontAtlas.h"
#include "2d/FontFNT.h"

NS_AX_BEGIN

void Label::computeAlignmentOffset()
{
    _linesOffsetX.clear();
    switch (_hAlignment)
    {
    case ax::TextHAlignment::LEFT:
        _linesOffsetX.assign(_numberOfLines, 0);
        break;
    case ax::TextHAlignment::CENTER:
        for (auto&& lineWidth : _linesWidth)
        {
            _linesOffsetX.emplace_back((_contentSize.width - lineWidth) / 2.f);
        }
        break;
    case ax::TextHAlignment::RIGHT:
        for (auto&& lineWidth : _linesWidth)
        {
            _linesOffsetX.emplace_back(_contentSize.width - lineWidth);
        }
        break;
    default:
        break;
    }

    switch (_vAlignment)
    {
    case ax::TextVAlignment::TOP:
        _letterOffsetY = _contentSize.height;
        break;
    case ax::TextVAlignment::CENTER:
        _letterOffsetY = (_contentSize.height + _textDesiredHeight) / 2.f;
        break;
    case ax::TextVAlignment::BOTTOM:
        _letterOffsetY = _textDesiredHeight;
        break;
    default:
        break;
    }
}

int Label::getFirstCharLen(const std::u32string& /*utf32Text*/, int /*startIndex*/, int /*textLen*/) const
{
    return 1;
}

int Label::getFirstWordLen(const std::u32string& utf32Text, int startIndex, int textLen) const
{
    int len          = 0;
    auto nextLetterX = 0;
    FontLetterDefinition letterDef;
    auto contentScaleFactor = AX_CONTENT_SCALE_FACTOR();

    for (int index = startIndex; index < textLen; ++index)
    {
        char32_t character = utf32Text[index];

        if (character == StringUtils::UnicodeCharacters::NewLine ||
            (!StringUtils::isUnicodeNonBreaking(character) &&
             (StringUtils::isUnicodeSpace(character) || StringUtils::isCJKUnicode(character))))
        {
            break;
        }

        if (!getFontLetterDef(character, letterDef))
        {
            break;
        }

        if (_maxLineWidth > 0.f)
        {
            auto letterX = (nextLetterX + letterDef.offsetX * _fontScale) / contentScaleFactor;

            if (letterX + letterDef.width * _fontScale > _maxLineWidth)
                break;
        }

        nextLetterX += static_cast<int>(letterDef.xAdvance * _fontScale + _additionalKerning);

        len++;
    }

    if (len == 0 && textLen)
        len = 1;

    return len;
}

bool Label::getFontLetterDef(char32_t character, FontLetterDefinition& letterDef) const
{
    if (character == StringUtils::UnicodeCharacters::NoBreakSpace)
    {
        // change no-break space to regular space
        // reason: some fonts have issue with no-break space:
        //   * no letter definition
        //   * not normal big width
        character = StringUtils::UnicodeCharacters::Space;
    }

    return _fontAtlas->getLetterDefinitionForChar(character, letterDef);
}

void Label::updateFontScale()
{
    auto font = _fontAtlas->getFont();
    if (_currentLabelType == LabelType::BMFONT)
    {
        FontFNT* bmFont       = (FontFNT*)font;
        auto originalFontSize = bmFont->getOriginalFontSize();
        _fontScale          = _bmFontSize * AX_CONTENT_SCALE_FACTOR() / originalFontSize;
    }
    else if (_currentLabelType == LabelType::TTF && _fontConfig.distanceFieldEnabled)
    {
        _fontScale = _fontConfig.fontSize / _fontConfig.baseFontSize;
    }
    else
    {
        _fontScale = 1.0f;
    }
}

bool Label::multilineTextWrap(const std::function<int(const std::u32string&, int, int)>& nextTokenLen)
{
    int textLen               = getStringLength();
    int lineIndex             = 0;
    float nextTokenX          = 0.f;
    float nextTokenY          = 0.f;
    float longestLine         = 0.f;
    float letterRight         = 0.f;
    float nextWhitespaceWidth = 0.f;

    auto contentScaleFactor = AX_CONTENT_SCALE_FACTOR();

    float lineSpacing       = _lineSpacing * contentScaleFactor;
    float highestY          = 0.f;
    float lowestY           = 0.f;
    FontLetterDefinition letterDef;
    Vec2 letterPosition;
    bool nextChangeSize = true;

    this->updateFontScale();

    for (int index = 0; index < textLen;)
    {
        char32_t character = _utf32Text[index];
        if (character == StringUtils::UnicodeCharacters::NewLine)
        {
            _linesWidth.emplace_back(letterRight);
            letterRight = 0.f;
            lineIndex++;
            nextTokenX = 0.f;
            nextTokenY -= _lineHeight * _fontScale + lineSpacing;
            recordPlaceholderInfo(index, character);
            index++;
            continue;
        }

        auto tokenLen         = nextTokenLen(_utf32Text, index, textLen);
        float tokenHighestY   = highestY;
        float tokenLowestY    = lowestY;
        float tokenRight      = letterRight;
        float nextLetterX     = nextTokenX;
        float whitespaceWidth = nextWhitespaceWidth;
        bool newLine          = false;
        for (int tmp = 0; tmp < tokenLen; ++tmp)
        {
            int letterIndex = index + tmp;
            character       = _utf32Text[letterIndex];
            if (character == StringUtils::UnicodeCharacters::CarriageReturn)
            {
                recordPlaceholderInfo(letterIndex, character);
                continue;
            }

            // \b - Next char not change x position
            if (character == StringUtils::UnicodeCharacters::NextCharNoChangeX)
            {
                nextChangeSize = false;
                recordPlaceholderInfo(letterIndex, character);
                continue;
            }

            if (!getFontLetterDef(character, letterDef))
            {
                recordPlaceholderInfo(letterIndex, character);
                AXLOG("LabelTextFormatter error: can't find letter definition in font file for letter: 0x%x",
                      character);
                continue;
            }

            auto letterX = (nextLetterX + letterDef.offsetX * _fontScale) / contentScaleFactor;
            if (_enableWrap && _maxLineWidth > 0.f && nextTokenX > 0.f &&
                letterX + letterDef.width * _fontScale > _maxLineWidth && !StringUtils::isUnicodeSpace(character) &&
                nextChangeSize)
            {
                _linesWidth.emplace_back(letterRight - whitespaceWidth);
                nextWhitespaceWidth = 0.f;
                letterRight         = 0.f;
                lineIndex++;
                nextTokenX = 0.f;
                nextTokenY -= (_lineHeight * _fontScale + lineSpacing);
                newLine = true;
                break;
            }
            else
            {
                letterPosition.x = letterX;
            }
            letterPosition.y = (nextTokenY - letterDef.offsetY * _fontScale) / contentScaleFactor;
            recordLetterInfo(letterPosition, character, letterIndex, lineIndex);

            if (nextChangeSize)
            {
                float newLetterWidth = 0.f;
                if (_horizontalKernings && letterIndex < textLen - 1)
                    newLetterWidth = static_cast<float>(_horizontalKernings[letterIndex + 1]);
                newLetterWidth += letterDef.xAdvance * _fontScale + _additionalKerning;

                nextLetterX += newLetterWidth;
                tokenRight = nextLetterX / contentScaleFactor;

                if (StringUtils::isUnicodeSpace(character))
                {
                    nextWhitespaceWidth += newLetterWidth / contentScaleFactor;
                }
                else
                {
                    nextWhitespaceWidth = 0;
                }
            }
            nextChangeSize = true;

            if (tokenHighestY < letterPosition.y)
                tokenHighestY = letterPosition.y;
            if (tokenLowestY > letterPosition.y - letterDef.height * _fontScale)
                tokenLowestY = letterPosition.y - letterDef.height * _fontScale;
        }

        if (newLine)
        {
            continue;
        }

        nextTokenX  = nextLetterX;
        letterRight = tokenRight;
        if (highestY < tokenHighestY)
            highestY = tokenHighestY;
        if (lowestY > tokenLowestY)
            lowestY = tokenLowestY;

        index += tokenLen;
    }

    if (_linesWidth.empty())
    {
        _linesWidth.emplace_back(letterRight);
        longestLine = letterRight;
    }
    else
    {
        _linesWidth.emplace_back(letterRight - nextWhitespaceWidth);
        for (auto&& lineWidth : _linesWidth)
        {
            if (longestLine < lineWidth)
                longestLine = lineWidth;
        }
    }

    _numberOfLines     = lineIndex + 1;
    _textDesiredHeight = (_numberOfLines * _lineHeight * _fontScale) / contentScaleFactor;
    if (_numberOfLines > 1)
        _textDesiredHeight += (_numberOfLines - 1) * _lineSpacing; // ?? use scaled lineSpacing
    Vec2 contentSize(_labelWidth, _labelHeight);
    if (_labelWidth <= 0.f)
        contentSize.width = longestLine;
    if (_labelHeight <= 0.f)
        contentSize.height = _textDesiredHeight;
    setContentSize(contentSize);

    _tailoredTopY    = contentSize.height;
    _tailoredBottomY = 0.f;
    if (highestY > 0.f)
        _tailoredTopY = contentSize.height + highestY;
    if (lowestY < -_textDesiredHeight)
        _tailoredBottomY = _textDesiredHeight + lowestY;

    return true;
}

bool Label::multilineTextWrapByWord()
{
    return multilineTextWrap(AX_CALLBACK_3(Label::getFirstWordLen, this));
}

bool Label::multilineTextWrapByChar()
{
    return multilineTextWrap(AX_CALLBACK_3(Label::getFirstCharLen, this));
}

bool Label::isVerticalClamp()
{
    if (_textDesiredHeight > _contentSize.height)
    {
        return true;
    }
    else
    {
        return false;
    }
}

bool Label::isHorizontalClamp()
{
    bool letterClamp = false;
    
    for (int ctr = 0; ctr < _lengthOfString; ++ctr)
    {
        if (_lettersInfo[ctr].valid)
        {
            auto& letterDef = _fontAtlas->_letterDefinitions[_lettersInfo[ctr].utf32Char];

            auto px        = _lettersInfo[ctr].positionX + letterDef.width / 2 * _fontScale;
            auto lineIndex = _lettersInfo[ctr].lineIndex;

            if (_labelWidth > 0.f)
            {
                if (!this->_enableWrap)
                {
                    if (px > _contentSize.width)
                    {
                        letterClamp = true;
                        break;
                    }
                }
                else
                {
                    auto wordWidth = this->_linesWidth[lineIndex];
                    if (wordWidth > this->_contentSize.width && (px > _contentSize.width))
                    {
                        letterClamp = true;
                        break;
                    }
                }
            }
        }
    }

    return letterClamp;
}

void Label::shrinkLabelToContentSize(const std::function<bool(void)>& lambda)
{
    float fontSize = this->getRenderingFontSize();

    int i                     = 0;
    auto letterDefinition     = _fontAtlas->_letterDefinitions;
    auto tempLetterDefinition = letterDefinition;
    float originalLineHeight  = _lineHeight;
    bool flag                 = true;
    while (lambda())
    {
        ++i;
        float newFontSize = fontSize - i;
        flag              = false;
        if (newFontSize <= 0)
        {
            break;
        }
        float scale = newFontSize / fontSize;
        std::swap(_fontAtlas->_letterDefinitions, tempLetterDefinition);
        _fontAtlas->scaleFontLetterDefinition(scale);
        this->setLineHeight(originalLineHeight * scale);
        if (_maxLineWidth > 0.f && !_lineBreakWithoutSpaces)
        {
            multilineTextWrapByWord();
        }
        else
        {
            multilineTextWrapByChar();
        }
        computeAlignmentOffset();
        tempLetterDefinition = letterDefinition;
    }
    this->setLineHeight(originalLineHeight);
    std::swap(_fontAtlas->_letterDefinitions, letterDefinition);

    if (!flag)
    {
        if (fontSize - i >= 0)
        {
            this->scaleFontSize(fontSize - i);
        }
    }
}

void Label::recordLetterInfo(const ax::Vec2& point, char32_t utf32Char, int letterIndex, int lineIndex)
{
    if (static_cast<std::size_t>(letterIndex) >= _lettersInfo.size())
    {
        LetterInfo tmpInfo;
        _lettersInfo.emplace_back(tmpInfo);
    }
    _lettersInfo[letterIndex].lineIndex  = lineIndex;
    _lettersInfo[letterIndex].utf32Char  = utf32Char;
    _lettersInfo[letterIndex].valid      = _fontAtlas->_letterDefinitions[utf32Char].validDefinition;
    _lettersInfo[letterIndex].positionX  = point.x;
    _lettersInfo[letterIndex].positionY  = point.y;
    _lettersInfo[letterIndex].atlasIndex = -1;
}

void Label::recordPlaceholderInfo(int letterIndex, char32_t utf32Char)
{
    if (static_cast<std::size_t>(letterIndex) >= _lettersInfo.size())
    {
        LetterInfo tmpInfo;
        _lettersInfo.emplace_back(tmpInfo);
    }
    _lettersInfo[letterIndex].utf32Char = utf32Char;
    _lettersInfo[letterIndex].valid     = false;
}

NS_AX_END