/****************************************************************************
 * Copyright (C) 2015 Dimok
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ****************************************************************************/

#include <gui/GuiImageData.h>
#include <gui/memory.h>
#include <malloc.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

/**
 * Constructor for the GuiImageData class.
 */
GuiImageData::GuiImageData() {
    texture    = NULL;
    sampler    = NULL;
    memoryType = eMemTypeMEM2;
}

/**
 * Constructor for the GuiImageData class.
 */
GuiImageData::GuiImageData(const uint8_t *img, int32_t imgSize, GX2TexClampMode textureClamp, GX2SurfaceFormat textureFormat) {
    texture = NULL;
    sampler = NULL;
    loadImage(img, imgSize, textureClamp, textureFormat);
}

/**
 * Constructor for the GuiImageData class.
 */

GuiImageData::GuiImageData(const char *path, GX2TexClampMode textureClamp, GX2SurfaceFormat textureFormat) {
    texture = NULL;
    sampler = NULL;
    loadImageFromFile(path, textureClamp, textureFormat);
}

/**
 * Destructor for the GuiImageData class.
 */
GuiImageData::~GuiImageData() {
    releaseData();
}

void GuiImageData::releaseData(void) {
    if (texture) {
        if (texture->surface.image) {
            switch (memoryType) {
                default:
                case eMemTypeMEM2:
                    free(texture->surface.image);
                    break;
                case eMemTypeMEM1:
                    MEM1_free(texture->surface.image);
                    break;
                case eMemTypeMEMBucket:
                    MEMBucket_free(texture->surface.image);
                    break;
            }
        }
        delete texture;
        texture = NULL;
    }
    if (sampler) {
        delete sampler;
        sampler = NULL;
    }
}

void GuiImageData::loadImageFromFile(const char *path, GX2TexClampMode textureClamp, GX2SurfaceFormat textureFormat) {
    FILE *file = fopen(path, "rb");
    if (file) {
        off_t i = ftello(file);
        if (fseek(file, 0, SEEK_END) == 0) {
            off_t fileSize = ftello(file);
            if (fileSize > 8) {
                fseeko(file, i, SEEK_SET);
                uint8_t buffer[fileSize];
                if (fread(buffer, 1, fileSize, file) == fileSize) {
                    loadImage(buffer, fileSize, textureClamp, textureFormat);
                }
            }
        }
        fclose(file);
    }
}

void GuiImageData::loadImage(const uint8_t *img, int32_t imgSize, GX2TexClampMode textureClamp, GX2SurfaceFormat textureFormat) {
    if (!img || (imgSize < 8)) {
        return;
    }

    releaseData();
    gdImagePtr gdImg = 0;

    if (img[0] == 0xFF && img[1] == 0xD8) {
        //! not needed for now therefore comment out to safe ELF size
        //! if needed uncomment, adds 200 kb to the ELF size
        // IMAGE_JPEG
        gdImg = gdImageCreateFromJpegPtr(imgSize, (uint8_t *) img);
    } else if (img[0] == 'B' && img[1] == 'M') {
        // IMAGE_BMP
        gdImg = gdImageCreateFromBmpPtr(imgSize, (uint8_t *) img);
    } else if (img[0] == 0x89 && img[1] == 'P' && img[2] == 'N' && img[3] == 'G') {
        // IMAGE_PNG
        gdImg = gdImageCreateFromPngPtr(imgSize, (uint8_t *) img);
    }
    //!This must be last since it can also intefere with outher formats
    else if (img[0] == 0x00) {
        // Try loading TGA image
        gdImg = gdImageCreateFromTgaPtr(imgSize, (uint8_t *) img);
    }

    if (gdImg == 0) {
        return;
    }

    uint32_t width  = (gdImageSX(gdImg));
    uint32_t height = (gdImageSY(gdImg));

    //! Initialize texture
    texture = new GX2Texture;
    GX2InitTexture(texture, width, height, 1, 0, textureFormat, GX2_SURFACE_DIM_TEXTURE_2D, GX2_TILE_MODE_LINEAR_ALIGNED);

    //! if this fails something went horribly wrong
    if (texture->surface.imageSize == 0) {
        delete texture;
        texture = NULL;
        gdImageDestroy(gdImg);
        return;
    }

    //! allocate memory for the surface
    memoryType             = eMemTypeMEM2;
    texture->surface.image = memalign(texture->surface.alignment, texture->surface.imageSize);
    //! try MEM1 on failure
    if (!texture->surface.image) {
        memoryType             = eMemTypeMEM1;
        texture->surface.image = MEM1_alloc(texture->surface.imageSize, texture->surface.alignment);
    }
    //! try MEM bucket on failure
    if (!texture->surface.image) {
        memoryType             = eMemTypeMEMBucket;
        texture->surface.image = MEMBucket_alloc(texture->surface.imageSize, texture->surface.alignment);
    }
    //! check if memory is available for image
    if (!texture->surface.image) {
        gdImageDestroy(gdImg);
        delete texture;
        texture = NULL;
        return;
    }
    //! set mip map data pointer
    texture->surface.mipmaps = NULL;
    //! convert image to texture
    switch (textureFormat) {
        default:
        case GX2_SURFACE_FORMAT_UNORM_R8_G8_B8_A8:
            gdImageToUnormR8G8B8A8(gdImg, (uint32_t *) texture->surface.image, texture->surface.width, texture->surface.height, texture->surface.pitch);
            break;
        case GX2_SURFACE_FORMAT_UNORM_R5_G6_B5:
            gdImageToUnormR5G6B5(gdImg, (uint16_t *) texture->surface.image, texture->surface.width, texture->surface.height, texture->surface.pitch);
            break;
    }

    //! free memory of image as its not needed anymore
    gdImageDestroy(gdImg);

    //! invalidate the memory
    GX2Invalidate(GX2_INVALIDATE_MODE_CPU_TEXTURE, texture->surface.image, texture->surface.imageSize);
    //! initialize the sampler
    sampler = new GX2Sampler;
    GX2InitSampler(sampler, textureClamp, GX2_TEX_XY_FILTER_MODE_LINEAR);
}

void GuiImageData::gdImageToUnormR8G8B8A8(gdImagePtr gdImg, uint32_t *imgBuffer, uint32_t width, uint32_t height, uint32_t pitch) {
    for (uint32_t y = 0; y < height; ++y) {
        for (uint32_t x = 0; x < width; ++x) {
            uint32_t pixel = gdImageGetPixel(gdImg, x, y);

            uint8_t a = 254 - 2 * ((uint8_t) gdImageAlpha(gdImg, pixel));
            if (a == 254) { a++; }

            uint8_t r = gdImageRed(gdImg, pixel);
            uint8_t g = gdImageGreen(gdImg, pixel);
            uint8_t b = gdImageBlue(gdImg, pixel);

            imgBuffer[y * pitch + x] = (r << 24) | (g << 16) | (b << 8) | (a);
        }
    }
}

//! TODO: figure out why this seems to not work correct yet
void GuiImageData::gdImageToUnormR5G6B5(gdImagePtr gdImg, uint16_t *imgBuffer, uint32_t width, uint32_t height, uint32_t pitch) {
    for (uint32_t y = 0; y < height; ++y) {
        for (uint32_t x = 0; x < width; ++x) {
            uint32_t pixel = gdImageGetPixel(gdImg, x, y);

            uint8_t r = gdImageRed(gdImg, pixel);
            uint8_t g = gdImageGreen(gdImg, pixel);
            uint8_t b = gdImageBlue(gdImg, pixel);

            imgBuffer[y * pitch + x] = ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3);
        }
    }
}