/*
 * FreeTypeGX is a wrapper class for libFreeType which renders a compiled
 * FreeType parsable font into a GX texture for Wii homebrew development.
 * Copyright (C) 2008 Armin Tamzarian
 * Modified by Dimok, 2010
 *
 * This file is part of FreeTypeGX.
 *
 * FreeTypeGX 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 3 of the License, or
 * (at your option) any later version.
 *
 * FreeTypeGX 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 FreeTypeGX.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "FreeTypeGX.h"

using namespace std;

/**
 * Convert a short char string to a wide char string.
 *
 * This routine converts a supplied short character string into a wide character string.
 * Note that it is the user's responsibility to clear the returned buffer once it is no longer needed.
 *
 * @param strChar   Character string to be converted.
 * @return Wide character representation of supplied character string.
 */

wchar_t* charToWideChar( const char* strChar )
{
    if ( !strChar )
        return NULL;

    wchar_t *strWChar = new ( std::nothrow ) wchar_t[strlen( strChar ) + 1];
    if ( !strWChar )
        return NULL;

    int bt = mbstowcs( strWChar, strChar, strlen( strChar ) );
    if ( bt > 0 )
    {
        strWChar[bt] = 0;
        return strWChar;
    }

    wchar_t *tempDest = strWChar;
    while ( ( *tempDest++ = *strChar++ ) );

    return strWChar;
}

/**
 * Default constructor for the FreeTypeGX class for WiiXplorer.
 */
FreeTypeGX::FreeTypeGX( const uint8_t* fontBuffer, FT_Long bufferSize )
{
    ftPointSize = 0;

    FT_Init_FreeType( &ftLibrary );
    FT_New_Memory_Face( ftLibrary, ( FT_Byte * )fontBuffer, bufferSize, 0, &ftFace );

    setVertexFormat( GX_VTXFMT1 );
    ftKerningEnabled = FT_HAS_KERNING( ftFace );
}

/**
 * Default destructor for the FreeTypeGX class.
 */
FreeTypeGX::~FreeTypeGX()
{
    unloadFont();
    FT_Done_Face( ftFace );
    FT_Done_FreeType( ftLibrary );
}

/**
 * Setup the vertex attribute formats for the glyph textures.
 *
 * This function sets up the vertex format for the glyph texture on the specified vertex format index.
 * Note that this function should not need to be called except if the vertex formats are cleared or the specified
 * vertex format index is modified.
 *
 * @param vertexIndex   Vertex format index (GX_VTXFMT*) of the glyph textures as defined by the libogc gx.h header file.
*/
void FreeTypeGX::setVertexFormat( uint8_t vertexInd )
{
    vertexIndex = vertexInd;
    GX_SetVtxAttrFmt( vertexIndex, GX_VA_POS, GX_POS_XYZ, GX_S16, 0 );
    GX_SetVtxAttrFmt( vertexIndex, GX_VA_TEX0, GX_TEX_ST, GX_F32, 0 );
    GX_SetVtxAttrFmt( vertexIndex, GX_VA_CLR0, GX_CLR_RGBA, GX_RGBA8, 0 );
}

/**
 * Clears all loaded font glyph data.
 *
 * This routine clears all members of the font map structure and frees all allocated memory back to the system.
 */
void FreeTypeGX::unloadFont()
{
    if ( this->fontData.size() == 0 )
        return;

    map<int16_t, map<wchar_t, ftgxCharData> >::iterator itr;
    map<wchar_t, ftgxCharData>::iterator itr2;

    for ( itr = fontData.begin(); itr != fontData.end(); itr++ )
    {
        for ( itr2 = itr->second.begin(); itr2 != itr->second.end(); itr2++ )
            free( itr2->second.glyphDataTexture );

        itr->second.clear();
    }

    fontData.clear();
    ftgxAlign.clear();
}

/**
 * Caches the given font glyph in the instance font texture buffer.
 *
 * This routine renders and stores the requested glyph's bitmap and relevant information into its own quickly addressible
 * structure within an instance-specific map.
 *
 * @param charCode  The requested glyph's character code.
 * @return A pointer to the allocated font structure.
 */
ftgxCharData * FreeTypeGX::cacheGlyphData( wchar_t charCode, int16_t pixelSize )
{
    map<int16_t, map<wchar_t, ftgxCharData> >::iterator itr;
    map<wchar_t, ftgxCharData>::iterator itr2;

    itr = fontData.find( pixelSize );
    if ( itr != fontData.end() )
    {
        itr2 = itr->second.find( charCode );

        if ( itr2 != itr->second.end() )
        {
            return &itr2->second;
        }
    }

    FT_UInt gIndex;
    uint16_t textureWidth = 0, textureHeight = 0;

    if ( ftPointSize != pixelSize )
    {
        ftPointSize = pixelSize;
        FT_Set_Pixel_Sizes( ftFace, 0, ftPointSize );

        //!Cache ascender and decender as well
        map<int16_t, ftgxDataOffset>::iterator itrAlign = ftgxAlign.find( ftPointSize );
        if ( itrAlign == ftgxAlign.end() )
        {
            ftgxAlign[ftPointSize].ascender = ( int16_t ) ftFace->size->metrics.ascender >> 6;
            ftgxAlign[ftPointSize].descender = ( int16_t ) ftFace->size->metrics.descender >> 6;
            ftgxAlign[ftPointSize].max = 0;
            ftgxAlign[ftPointSize].min = 0;
        }
    }

    gIndex = FT_Get_Char_Index( ftFace, ( FT_ULong ) charCode );
    if ( gIndex != 0 && FT_Load_Glyph( ftFace, gIndex, FT_LOAD_DEFAULT | FT_LOAD_RENDER ) == 0 )
    {
        if ( ftFace->glyph->format == FT_GLYPH_FORMAT_BITMAP )
        {
            FT_Bitmap *glyphBitmap = &ftFace->glyph->bitmap;

            textureWidth = glyphBitmap->width + ( 4 - glyphBitmap->width % 4 ) % 4;
            textureHeight = glyphBitmap->rows + ( 4 - glyphBitmap->rows % 4 ) % 4;

            fontData[pixelSize][charCode].renderOffsetX = ( int16_t ) ftFace->glyph->bitmap_left;
            fontData[pixelSize][charCode].glyphAdvanceX = ( uint16_t ) ( ftFace->glyph->advance.x >> 6 );
            fontData[pixelSize][charCode].glyphIndex = ( uint32_t ) gIndex;
            fontData[pixelSize][charCode].textureWidth = ( uint16_t ) textureWidth;
            fontData[pixelSize][charCode].textureHeight = ( uint16_t ) textureHeight;
            fontData[pixelSize][charCode].renderOffsetY = ( int16_t ) ftFace->glyph->bitmap_top;
            fontData[pixelSize][charCode].renderOffsetMax = ( int16_t ) ftFace->glyph->bitmap_top;
            fontData[pixelSize][charCode].renderOffsetMin = ( int16_t ) glyphBitmap->rows - ftFace->glyph->bitmap_top;
            fontData[pixelSize][charCode].glyphDataTexture = NULL;

            loadGlyphData( glyphBitmap, &fontData[pixelSize][charCode] );

            return &fontData[pixelSize][charCode];
        }
    }
    return NULL;
}

/**
 * Locates each character in this wrapper's configured font face and proccess them.
 *
 * This routine locates each character in the configured font face and renders the glyph's bitmap.
 * Each bitmap and relevant information is loaded into its own quickly addressible structure within an instance-specific map.
 */
uint16_t FreeTypeGX::cacheGlyphDataComplete( int16_t pixelSize )
{
    uint32_t i = 0;
    FT_UInt gIndex;

    FT_ULong charCode = FT_Get_First_Char( ftFace, &gIndex );
    while ( gIndex != 0 )
    {
        if ( cacheGlyphData( charCode, pixelSize ) != NULL )
            ++i;
        charCode = FT_Get_Next_Char( ftFace, charCode, &gIndex );
    }
    return ( uint16_t )( i );
}

/**
 * Loads the rendered bitmap into the relevant structure's data buffer.
 *
 * This routine does a simple byte-wise copy of the glyph's rendered 8-bit grayscale bitmap into the structure's buffer.
 * Each byte is converted from the bitmap's intensity value into the a uint32_t RGBA value.
 *
 * @param bmp   A pointer to the most recently rendered glyph's bitmap.
 * @param charData  A pointer to an allocated ftgxCharData structure whose data represent that of the last rendered glyph.
 *
 *
 * Optimized for RGBA8 use by Dimok.
 */
void FreeTypeGX::loadGlyphData( FT_Bitmap *bmp, ftgxCharData *charData )
{
    int length =  ( ( ( ( charData->textureWidth + 3 ) >> 2 ) * ( ( charData->textureHeight + 3 ) >> 2 ) * 32 * 2 + 31 ) & ~31 );

    uint8_t * glyphData = ( uint8_t * ) memalign( 32, length );
    if ( !glyphData )
        return;

    memset( glyphData, 0x00, length );

    uint8_t *src = ( uint8_t * )bmp->buffer;
    uint32_t offset;

    for ( int imagePosY = 0; imagePosY < bmp->rows; ++imagePosY )
    {
        for ( int imagePosX = 0; imagePosX < bmp->width; ++imagePosX )
        {
            offset = ( ( ( ( imagePosY >> 2 ) * ( charData->textureWidth >> 2 ) + ( imagePosX >> 2 ) ) << 5 ) + ( ( imagePosY & 3 ) << 2 ) + ( imagePosX & 3 ) ) << 1;
            glyphData[offset] = *src;
            glyphData[offset+1] = *src;
            glyphData[offset+32] = *src;
            glyphData[offset+33] = *src;
            ++src;
        }
    }
    DCFlushRange( glyphData, length );

    charData->glyphDataTexture = glyphData;
}

/**
 * Determines the x offset of the rendered string.
 *
 * This routine calculates the x offset of the rendered string based off of a supplied positional format parameter.
 *
 * @param width Current pixel width of the string.
 * @param format    Positional format of the string.
 */
int16_t FreeTypeGX::getStyleOffsetWidth( uint16_t width, uint16_t format )
{
    if ( format & FTGX_JUSTIFY_LEFT )
        return 0;
    else if ( format & FTGX_JUSTIFY_CENTER )
        return -( width >> 1 );
    else if ( format & FTGX_JUSTIFY_RIGHT )
        return -width;
    return 0;
}

/**
 * Determines the y offset of the rendered string.
 *
 * This routine calculates the y offset of the rendered string based off of a supplied positional format parameter.
 *
 * @param offset    Current pixel offset data of the string.
 * @param format    Positional format of the string.
 */
int16_t FreeTypeGX::getStyleOffsetHeight( int16_t format, uint16_t pixelSize )
{
    map<int16_t, ftgxDataOffset>::iterator itrAlign = ftgxAlign.find( pixelSize );
    if ( itrAlign == ftgxAlign.end() )
        return 0;

    switch ( format & FTGX_ALIGN_MASK )
    {
        case FTGX_ALIGN_TOP:
            return itrAlign->second.ascender;

        case FTGX_ALIGN_MIDDLE:
        default:
            return ( itrAlign->second.ascender + itrAlign->second.descender + 1 ) >> 1;

        case FTGX_ALIGN_BOTTOM:
            return itrAlign->second.descender;

        case FTGX_ALIGN_BASELINE:
            return 0;

        case FTGX_ALIGN_GLYPH_TOP:
            return itrAlign->second.max;

        case FTGX_ALIGN_GLYPH_MIDDLE:
            return ( itrAlign->second.max + itrAlign->second.min + 1 ) >> 1;

        case FTGX_ALIGN_GLYPH_BOTTOM:
            return itrAlign->second.min;
    }
    return 0;
}

/**
 * Processes the supplied text string and prints the results at the specified coordinates.
 *
 * This routine processes each character of the supplied text string, loads the relevant preprocessed bitmap buffer,
 * a texture from said buffer, and loads the resultant texture into the EFB.
 *
 * @param x Screen X coordinate at which to output the text.
 * @param y Screen Y coordinate at which to output the text. Note that this value corresponds to the text string origin and not the top or bottom of the glyphs.
 * @param text  NULL terminated string to output.
 * @param color Optional color to apply to the text characters. If not specified default value is ftgxWhite: (GXColor){0xff, 0xff, 0xff, 0xff}
 * @param textStyle Flags which specify any styling which should be applied to the rendered string.
 * @return The number of characters printed.
 */
uint16_t FreeTypeGX::drawText( int16_t x, int16_t y, int16_t z, const wchar_t *text, int16_t pixelSize, GXColor color, uint16_t textStyle, uint16_t textWidth, uint16_t widthLimit )
{
    if ( !text )
        return 0;

    uint16_t fullTextWidth = textWidth > 0 ? textWidth : getWidth( text, pixelSize );
    uint16_t x_pos = x, printed = 0;
    uint16_t x_offset = 0, y_offset = 0;
    GXTexObj glyphTexture;
    FT_Vector pairDelta;

    if ( textStyle & FTGX_JUSTIFY_MASK )
    {
        x_offset = getStyleOffsetWidth( fullTextWidth, textStyle );
    }
    if ( textStyle & FTGX_ALIGN_MASK )
    {
        y_offset = getStyleOffsetHeight( textStyle, pixelSize );
    }

    int i = 0;

    while ( text[i] )
    {
        if ( widthLimit > 0 && ( x_pos - x ) > widthLimit )
            break;

        ftgxCharData* glyphData = cacheGlyphData( text[i], pixelSize );

        if ( glyphData != NULL )
        {
            if ( ftKerningEnabled && i > 0 )
            {
                FT_Get_Kerning( ftFace, fontData[pixelSize][text[i - 1]].glyphIndex, glyphData->glyphIndex, FT_KERNING_DEFAULT, &pairDelta );
                x_pos += pairDelta.x >> 6;
            }

            GX_InitTexObj( &glyphTexture, glyphData->glyphDataTexture, glyphData->textureWidth, glyphData->textureHeight, GX_TF_RGBA8, GX_CLAMP, GX_CLAMP, GX_FALSE );
            copyTextureToFramebuffer( &glyphTexture, glyphData->textureWidth, glyphData->textureHeight, x_pos + glyphData->renderOffsetX + x_offset, y - glyphData->renderOffsetY + y_offset, z, color );

            x_pos += glyphData->glyphAdvanceX;
            ++printed;
        }
        ++i;
    }

    if ( textStyle & FTGX_STYLE_MASK )
    {
        getOffset( text, pixelSize, widthLimit );
        drawTextFeature( x + x_offset, y + y_offset, z, pixelSize, fullTextWidth, &ftgxAlign[pixelSize], textStyle, color );
    }

    return printed;
}

void FreeTypeGX::drawTextFeature( int16_t x, int16_t y, int16_t z, int16_t pixelSize, uint16_t width, ftgxDataOffset *offsetData, uint16_t format, GXColor color )
{
    uint16_t featureHeight = pixelSize >> 4 > 0 ? pixelSize >> 4 : 1;

    if ( format & FTGX_STYLE_UNDERLINE )
        this->copyFeatureToFramebuffer( width, featureHeight, x, y + 1, z, color );

    if ( format & FTGX_STYLE_STRIKE )
        this->copyFeatureToFramebuffer( width, featureHeight, x, y - ( ( offsetData->max ) >> 1 ), z, color );
}

/**
 * Processes the supplied string and return the width of the string in pixels.
 *
 * This routine processes each character of the supplied text string and calculates the width of the entire string.
 * Note that if precaching of the entire font set is not enabled any uncached glyph will be cached after the call to this function.
 *
 * @param text  NULL terminated string to calculate.
 * @return The width of the text string in pixels.
 */
uint16_t FreeTypeGX::getWidth( const wchar_t *text, int16_t pixelSize )
{
    if ( !text )
        return 0;

    uint16_t strWidth = 0;
    FT_Vector pairDelta;

    int i = 0;
    while ( text[i] )
    {
        ftgxCharData* glyphData = cacheGlyphData( text[i], pixelSize );

        if ( glyphData != NULL )
        {
            if ( ftKerningEnabled && ( i > 0 ) )
            {
                FT_Get_Kerning( ftFace, fontData[pixelSize][text[i - 1]].glyphIndex, glyphData->glyphIndex, FT_KERNING_DEFAULT, &pairDelta );
                strWidth += pairDelta.x >> 6;
            }

            strWidth += glyphData->glyphAdvanceX;
        }
        ++i;
    }
    return strWidth;
}

/**
 * Single char width
*/
uint16_t FreeTypeGX::getCharWidth( const wchar_t wChar, int16_t pixelSize, const wchar_t prevChar )
{
    uint16_t strWidth = 0;
    ftgxCharData * glyphData = cacheGlyphData( wChar, pixelSize );

    if ( glyphData != NULL )
    {
        if ( ftKerningEnabled && prevChar != 0x0000 )
        {
            FT_Vector pairDelta;
            FT_Get_Kerning( ftFace, fontData[pixelSize][prevChar].glyphIndex, glyphData->glyphIndex, FT_KERNING_DEFAULT, &pairDelta );
            strWidth += pairDelta.x >> 6;
        }
        strWidth += glyphData->glyphAdvanceX;
    }

    return strWidth;
}

/**
 * Processes the supplied string and return the height of the string in pixels.
 *
 * This routine processes each character of the supplied text string and calculates the height of the entire string.
 * Note that if precaching of the entire font set is not enabled any uncached glyph will be cached after the call to this function.
 *
 * @param text  NULL terminated string to calculate.
 * @return The height of the text string in pixels.
 */
uint16_t FreeTypeGX::getHeight( const wchar_t *text, int16_t pixelSize )
{
    getOffset( text, pixelSize );

    return ftgxAlign[pixelSize].max - ftgxAlign[pixelSize].min;
}

/**
 * Get the maximum offset above and minimum offset below the font origin line.
 *
 * This function calculates the maximum pixel height above the font origin line and the minimum
 * pixel height below the font origin line and returns the values in an addressible structure.
 *
 * @param text  NULL terminated string to calculate.
 * @param offset returns the max and min values above and below the font origin line
 *
 */
void FreeTypeGX::getOffset( const wchar_t *text, int16_t pixelSize, uint16_t widthLimit )
{
    if ( ftgxAlign.find( pixelSize ) != ftgxAlign.end() )
        return;

    int16_t strMax = 0, strMin = 9999;
    uint16_t currWidth = 0;

    int i = 0;

    while ( text[i] )
    {
        if ( widthLimit > 0 && currWidth >= widthLimit )
            break;

        ftgxCharData* glyphData = cacheGlyphData( text[i], pixelSize );

        if ( glyphData != NULL )
        {
            strMax = glyphData->renderOffsetMax > strMax ? glyphData->renderOffsetMax : strMax;
            strMin = glyphData->renderOffsetMin < strMin ? glyphData->renderOffsetMin : strMin;
            currWidth += glyphData->glyphAdvanceX;
        }

        ++i;
    }

    if ( ftPointSize != pixelSize )
    {
        ftPointSize = pixelSize;
        FT_Set_Pixel_Sizes( ftFace, 0, ftPointSize );
    }

    ftgxAlign[pixelSize].ascender = ftFace->size->metrics.ascender >> 6;
    ftgxAlign[pixelSize].descender = ftFace->size->metrics.descender >> 6;
    ftgxAlign[pixelSize].max = strMax;
    ftgxAlign[pixelSize].min = strMin;
}

/**
 * Copies the supplied texture quad to the EFB.
 *
 * This routine uses the in-built GX quad builder functions to define the texture bounds and location on the EFB target.
 *
 * @param texObj    A pointer to the glyph's initialized texture object.
 * @param texWidth  The pixel width of the texture object.
 * @param texHeight The pixel height of the texture object.
 * @param screenX   The screen X coordinate at which to output the rendered texture.
 * @param screenY   The screen Y coordinate at which to output the rendered texture.
 * @param color Color to apply to the texture.
 */
void FreeTypeGX::copyTextureToFramebuffer( GXTexObj *texObj, f32 texWidth, f32 texHeight, int16_t screenX, int16_t screenY, int16_t screenZ, GXColor color )
{
    GX_LoadTexObj( texObj, GX_TEXMAP0 );
    GX_InvalidateTexAll();

    GX_SetTevOp ( GX_TEVSTAGE0, GX_MODULATE );
    GX_SetVtxDesc ( GX_VA_TEX0, GX_DIRECT );

    GX_Begin( GX_QUADS, this->vertexIndex, 4 );
    GX_Position3s16( screenX, screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );
    GX_TexCoord2f32( 0.0f, 0.0f );

    GX_Position3s16( texWidth + screenX, screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );
    GX_TexCoord2f32( 1.0f, 0.0f );

    GX_Position3s16( texWidth + screenX, texHeight + screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );
    GX_TexCoord2f32( 1.0f, 1.0f );

    GX_Position3s16( screenX, texHeight + screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );
    GX_TexCoord2f32( 0.0f, 1.0f );
    GX_End();

    GX_SetTevOp( GX_TEVSTAGE0, GX_PASSCLR );
    GX_SetVtxDesc( GX_VA_TEX0, GX_NONE );
}

/**
 * Creates a feature quad to the EFB.
 *
 * This function creates a simple quad for displaying underline or strikeout text styling.
 *
 * @param featureWidth  The pixel width of the quad.
 * @param featureHeight The pixel height of the quad.
 * @param screenX   The screen X coordinate at which to output the quad.
 * @param screenY   The screen Y coordinate at which to output the quad.
 * @param color Color to apply to the texture.
 */
void FreeTypeGX::copyFeatureToFramebuffer( f32 featureWidth, f32 featureHeight, int16_t screenX, int16_t screenY, int16_t screenZ, GXColor color )
{
    GX_SetTevOp ( GX_TEVSTAGE0, GX_PASSCLR );
    GX_SetVtxDesc ( GX_VA_TEX0, GX_NONE );

    GX_Begin( GX_QUADS, this->vertexIndex, 4 );
    GX_Position3s16( screenX, screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );

    GX_Position3s16( featureWidth + screenX, screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );

    GX_Position3s16( featureWidth + screenX, featureHeight + screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );

    GX_Position3s16( screenX, featureHeight + screenY, screenZ );
    GX_Color4u8( color.r, color.g, color.b, color.a );
    GX_End();

    GX_SetTevOp( GX_TEVSTAGE0, GX_PASSCLR );
    GX_SetVtxDesc( GX_VA_TEX0, GX_NONE );
}