/*
 * Copyright (c) 2023 - 2025 the ThorVG project. All rights reserved.

 * 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.
 */


#ifndef TVG_GIF_ENCODER_H
#define TVG_GIF_ENCODER_H

#include "tvgCommon.h"

typedef struct
{
    uint8_t r[256];
    uint8_t g[256];
    uint8_t b[256];

    // k-d tree over RGB space, organized in heap fashion
    // i.e. left child of node i is node i*2, right child is node i*2+1
    // nodes 256-511 are implicitly the leaves, containing a color
    uint8_t treeSplitElt[256];
    uint8_t treeSplit[256];
} GifPalette;


typedef struct
{
    FILE* f;
    uint8_t* oldImage;
    uint8_t* tmpImage;
    GifPalette pal;
    bool firstFrame;
} GifWriter;


// Creates a gif file.
// The input GIFWriter is assumed to be uninitialized.
// The delay value is the time between frames in hundredths of a second - note that not all viewers pay much attention to this value.
bool gifBegin(GifWriter* writer, const char* filename, uint32_t width, uint32_t height, uint32_t delay);

// Writes out a new frame to a GIF in progress.
// The GIFWriter should have been created by GIFBegin.
// AFAIK, it is legal to use different bit depths for different frames of an image -
// this may be handy to save bits in animations that don't change much.
bool gifWriteFrame(GifWriter* writer, const uint8_t* image, uint32_t width, uint32_t height, uint32_t delay, bool transparent);


// Writes the EOF code, closes the file handle, and frees temp memory used by a GIF.
// Many if not most viewers will still display a GIF properly if the EOF code is missing,
// but it's still a good idea to write it out.
bool gifEnd(GifWriter* writer);

#endif //TVG_GIF_ENCODER_H
