/*
 *  The Mana World
 *  Copyright 2004 The Mana World Development Team
 *
 *  This file is part of The Mana World.
 *
 *  The Mana World 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 2 of the License, or
 *  any later version.
 *
 *  The Mana World 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 The Mana World; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  $Id$
 */

#include "graphics.h"

#include <cstdarg>
#include <png.h>

#include "log.h"

#include "graphic/imagerect.h"

#include "resources/image.h"

extern volatile int framesToDraw;

Graphics::Graphics():
    mScreen(0)
{
}

Graphics::~Graphics()
{
    _endDraw();
}

bool Graphics::setVideoMode(int w, int h, int bpp, bool fs, bool hwaccel)
{
    int displayFlags = SDL_ANYFORMAT;

    mFullscreen = fs;
    mHWAccel = hwaccel;

    if (fs) {
        displayFlags |= SDL_FULLSCREEN;
    }

    if (hwaccel) {
        displayFlags |= SDL_HWSURFACE | SDL_DOUBLEBUF;
    } else {
        displayFlags |= SDL_SWSURFACE;
    }

    mScreen = SDL_SetVideoMode(w, h, bpp, displayFlags);

    if (!mScreen) {
        return false;
    }

    char videoDriverName[64];

    if (SDL_VideoDriverName(videoDriverName, 64)) {
        logger->log("Using video driver: %s", videoDriverName);
    }
    else {
        logger->log("Using video driver: unkown");
    }

    const SDL_VideoInfo *vi = SDL_GetVideoInfo();

    logger->log("Possible to create hardware surfaces: %s",
            ((vi->hw_available) ? "yes" : "no"));
    logger->log("Window manager available: %s",
            ((vi->wm_available) ? "yes" : "no"));
    logger->log("Accelerated hardware to hardware blits: %s",
            ((vi->blit_hw) ? "yes" : "no"));
    logger->log("Accelerated hardware to hardware colorkey blits: %s",
            ((vi->blit_hw_CC) ? "yes" : "no"));
    logger->log("Accelerated hardware to hardware alpha blits: %s",
            ((vi->blit_hw_A) ? "yes" : "no"));
    logger->log("Accelerated software to hardware blits: %s",
            ((vi->blit_sw) ? "yes" : "no"));
    logger->log("Accelerated software to hardware colorkey blits: %s",
            ((vi->blit_sw_CC) ? "yes" : "no"));
    logger->log("Accelerated software to hardware alpha blits: %s",
            ((vi->blit_sw_A) ? "yes" : "no"));
    logger->log("Accelerated color fills: %s",
            ((vi->blit_fill) ? "yes" : "no"));
    logger->log("Available video memory: %d", vi->video_mem);

    setTarget(mScreen);

    return true;
}

bool Graphics::setFullscreen(bool fs)
{
    if (mFullscreen == fs) {
        return true;
    }

    return setVideoMode(mScreen->w, mScreen->h,
            mScreen->format->BitsPerPixel, fs, mHWAccel);
}

int Graphics::getWidth()
{
    return mScreen->w;
}

int Graphics::getHeight()
{
    return mScreen->h;
}

bool Graphics::drawImage(Image *image, int x, int y)
{
    return drawImage(image, 0, 0, x, y, image->bounds.w, image->bounds.h);
}

bool Graphics::drawImage(Image *image, int srcX, int srcY, int dstX, int dstY,
        int width, int height)
{
    dstX += mClipStack.top().xOffset;
    dstY += mClipStack.top().yOffset;

    srcX += image->bounds.x;
    srcY += image->bounds.y;

    // Check that preconditions for blitting are met.
    if (!mScreen || !image->image) return false;

    SDL_Rect dstRect;
    SDL_Rect srcRect;
    dstRect.x = dstX; dstRect.y = dstY;
    srcRect.x = srcX; srcRect.y = srcY;
    srcRect.w = width;
    srcRect.h = height;

    if (SDL_BlitSurface(image->image, &srcRect, mScreen, &dstRect) < 0) {
        return false;
    }

    return true;
}

void Graphics::drawImagePattern(Image *image, int x, int y, int w, int h)
{
    int iw = image->getWidth();
    int ih = image->getHeight();
    if (iw == 0 || ih == 0) return;

    int px = 0;                       // X position on pattern plane
    int py = 0;                       // Y position on pattern plane

    while (py < h) {
        while (px < w) {
            int dw = (px + iw >= w) ? w - px : iw;
            int dh = (py + ih >= h) ? h - py : ih;
            drawImage(image, 0, 0, x + px, y + py, dw, dh);
            px += iw;
        }
        py += ih;
        px = 0;
    }
}

void Graphics::drawImageRect(
        int x, int y, int w, int h,
        Image *topLeft, Image *topRight,
        Image *bottomLeft, Image *bottomRight,
        Image *top, Image *right,
        Image *bottom, Image *left,
        Image *center)
{
    pushClipArea(gcn::Rectangle(x, y, w, h));

    // Draw the center area
    drawImagePattern(center,
            topLeft->getWidth(), topLeft->getHeight(),
            w - topLeft->getWidth() - topRight->getWidth(),
            h - topLeft->getHeight() - bottomLeft->getHeight());

    // Draw the sides
    drawImagePattern(top,
            left->getWidth(), 0,
            w - left->getWidth() - right->getWidth(), top->getHeight());
    drawImagePattern(bottom,
            left->getWidth(), h - bottom->getHeight(),
            w - left->getWidth() - right->getWidth(),
            bottom->getHeight());
    drawImagePattern(left,
            0, top->getHeight(),
            left->getWidth(),
            h - top->getHeight() - bottom->getHeight());
    drawImagePattern(right,
            w - right->getWidth(), top->getHeight(),
            right->getWidth(),
            h - top->getHeight() - bottom->getHeight());

    // Draw the corners
    drawImage(topLeft, 0, 0);
    drawImage(topRight, w - topRight->getWidth(), 0);
    drawImage(bottomLeft, 0, h - bottomLeft->getHeight());
    drawImage(bottomRight,
            w - bottomRight->getWidth(),
            h - bottomRight->getHeight());

    popClipArea();
}

void Graphics::drawImageRect(
        int x, int y, int w, int h,
        const ImageRect &imgRect)
{
    drawImageRect(x, y, w, h,
            imgRect.grid[0], imgRect.grid[2], imgRect.grid[6], imgRect.grid[8],
            imgRect.grid[1], imgRect.grid[5], imgRect.grid[7], imgRect.grid[3],
            imgRect.grid[4]);
}

void Graphics::updateScreen()
{
    SDL_Flip(mScreen);

    // Decrement frame counter when using framerate limiting
    if (framesToDraw > 1) framesToDraw--;

    // Wait while we're not allowed to draw next frame yet
    while (framesToDraw == 1)
    {
        SDL_Delay(10);
    }
}

bool Graphics::saveScreenshot(char *filename, ...)
{
    va_list ap;
    char *newname = (char *)malloc(32);
    va_start(ap, filename);
    vsprintf(newname, filename, ap);
    va_end(ap);

    FILE *fp = fopen(newname, "wb");
    if (!fp)
    {
        logger->log("could not open file &s for writing", newname);
        return false;
    }
    
    png_structp png_ptr;
    png_infop info_ptr;
    png_bytep *row_pointers;
    int colortype;
    
    #if SDL_BYTEORDER == SDL_BIG_ENDIAN
    int rmask = 0xff000000;
    int gmask = 0x00ff0000;
    int bmask = 0x0000ff00;
    int amask = 0x000000ff;
    #else
    int rmask = 0x000000ff;
    int gmask = 0x0000ff00;
    int bmask = 0x00ff0000;
    int amask = 0xff000000;
    #endif
    
    SDL_Surface *surface = SDL_CreateRGBSurface(SDL_SWSURFACE, mScreen->w, 
    mScreen->h, 32, rmask, gmask, bmask, amask);
    //SDL_LockSurface(mScreen);
    SDL_BlitSurface(mScreen, NULL, surface, NULL);
    //SDL_UnlockSurface(mScreen);
        
    SDL_LockSurface(surface);
        
    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
    if (!png_ptr)
    {
        logger->log("Had trouble creating png_structp");
        return false;
    }
    
    info_ptr = png_create_info_struct(png_ptr);
    if (!info_ptr)
    {
        logger->log("Could not create png_info");
        return false;
    }
        
    
    if (setjmp(png_ptr->jmpbuf))
    {
        logger->log("problem writing to %s", newname);
        return false;
    }    

    png_init_io(png_ptr, fp);

    if (mScreen->format->BitsPerPixel == 24) colortype = PNG_COLOR_TYPE_RGB;
    else colortype = PNG_COLOR_TYPE_RGB_ALPHA;
    
    png_set_IHDR(png_ptr, info_ptr, surface->w, surface->h, 8,colortype,
    PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
    
    png_write_info(png_ptr, info_ptr);
    
    png_set_packing(png_ptr);
    
    row_pointers = (png_bytep*) malloc(sizeof(png_bytep)*surface->h);
    if (!row_pointers)
    {
        logger->log("Had trouble converting surface to row pointers");
        return false;
    }
    
    for (int i = 0; i < surface->h; i++)
    row_pointers[i] = (png_bytep)(Uint8 *)surface->pixels + i * surface->pitch;

    png_write_image(png_ptr, row_pointers);
    png_write_end(png_ptr, info_ptr);
    fclose(fp);
    if (row_pointers) free(row_pointers);
        
    if (info_ptr->palette) free(info_ptr->palette);
        
    png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
                
    SDL_UnlockSurface(surface);
    SDL_FreeSurface(surface);

    return true;
}