#include "surface.h"
#include "gif.c"

struct jSurface_s
{
    Uint8 *data;
    Uint16 w, h;
};

// Constructor
Surface::Surface(const char *filename, jSurface dest)
{
    surface = loadSurface(filename);
    destSurface = dest;
    texture = nullptr;

    loadPalette(filename);
    transparentColor = 0;
}

// Constructor
Surface::Surface(int width, int height, SDL_Texture *tex)
{
    surface = newSurface(width, height);
    destSurface = nullptr;
    texture = tex;

    clearPalette(0);
    transparentColor = 0;
}

// Destructor
Surface::~Surface()
{
    deleteSurface(surface);
    deleteSurface(destSurface);
}

// Crea una surface
jSurface Surface::newSurface(int w, int h)
{
    jSurface surf = (jSurface)malloc(sizeof(jSurface_s));
    surf->w = w;
    surf->h = h;
    surf->data = (Uint8 *)malloc(w * h);
    return surf;
}

// Borra una surface
void Surface::deleteSurface(jSurface surf)
{
    if (surf == nullptr)
    {
        return;
    }

    if (surf->data != nullptr)
    {
        free(surf->data);
    }

    free(surf);
}

// Establece una surface de destino donde hacer el blit
void Surface::setDest(jSurface surf)
{
    destSurface = surf;
}

// Establece una textura donde hacer el flip
void Surface::setTexture(SDL_Texture *tex)
{
    texture = tex;
}

// Crea una surface a partir de un fichero .gif
jSurface Surface::loadSurface(const char *filename)
{
    FILE *f = fopen(filename, "rb");
    if (!f)
    {
        return nullptr;
    }

    fseek(f, 0, SEEK_END);
    long size = ftell(f);
    fseek(f, 0, SEEK_SET);
    Uint8 *buffer = (Uint8 *)malloc(size);
    fread(buffer, size, 1, f);
    fclose(f);

    Uint16 w, h;
    Uint8 *pixels = LoadGif(buffer, &w, &h);
    if (pixels == nullptr)
    {
        return nullptr;
    }
    jSurface surf = (jSurface)malloc(sizeof(jSurface_s));
    surf->w = w;
    surf->h = h;
    surf->data = pixels;
    free(buffer);
    return surf;
}

// Carga una palette desde un fichero .gif
void Surface::loadPalette(const char *filename)
{
    FILE *f = fopen(filename, "rb");
    if (!f)
    {
        return;
    }

    fseek(f, 0, SEEK_END);
    long size = ftell(f);
    fseek(f, 0, SEEK_SET);
    Uint8 *buffer = (Uint8 *)malloc(size);
    fread(buffer, size, 1, f);
    fclose(f);

    Uint32 *pal = LoadPalette(buffer);
    if (pal == nullptr)
    {
        return;
    }
    free(buffer);
    for (int i = 0; i < 256; ++i)
    {
        palette[i] = pal[i];
    }
}

// Cambia un color de la palette
void Surface::setPaletteColor(int index, Uint32 color)
{
    palette[index] = color;
}

// Limpia la surface
void Surface::cls(Uint8 color)
{
    for (int i = 0; i < surface->w * surface->h; ++i)
    {
        surface->data[i] = color;
    }
}

// Volca la surface a una textura
void Surface::flip(SDL_Texture *texture)
{
    Uint32 *pixels;
    int pitch;
    SDL_LockTexture(texture, nullptr, (void **)&pixels, &pitch);
    for (int i = 0; i < surface->w * surface->h; ++i)
    {
        pixels[i] = palette[surface->data[i]];
    }
    SDL_UnlockTexture(texture);
}

// Escribe pixels en destSurface
void Surface::putPixel(int x, int y, Uint8 color)
{
    // if (x < 0 || y < 0 || x >= jDestSurf->w || y >= jDestSurf->h || color == transparentColor)
    if (x < 0 || y < 0 || x >= destSurface->w || y >= destSurface->h)
    {
        return;
    }
    destSurface->data[x + y * destSurface->w] = color;
}

// Lee pixels en surface
Uint8 Surface::getPixel(int x, int y)
{
    return surface->data[x + y * surface->w];
}

// Copia pixels desde surface a destSurface
void Surface::blit(int dx, int dy, int sx, int sy, int w, int h)
{
    if (surface == nullptr)
    {
        return;
    }

    for (int iy = 0; iy < h; ++iy)
    {
        for (int ix = 0; ix < w; ++ix)
        {
            putPixel(dx + ix, dy + iy, getPixel(sx + ix, sy + iy));
        }
    }
}

// Limpia la paleta
void Surface::clearPalette(Uint32 color)
{
    for (int i = 0; i < 256; ++i)
    {
        palette[i] = color;
    }
}