#include <GL/gl.h> 
#include <GL/glu.h> 
#include <GL/osmesa.h> 

#include <Magick++.h> 
#include <string> 
#include <iostream> 
#include <list> 

#include <dds.h> 

#include <LuaHandle.h>
#include <BLua.h>

#ifndef WIN32
#define WEAK __attribute__ ((weak))
#else
#define WEAK
#endif

OSMesaContext ctx = 0;
void *buffer = 0;
int width = -1;
int height = -1;
bool upscale = false;

class scene_t : public Base {
  public:
    std::list<Magick::Image> scene;
    String filename, tmp_filename;
};void empty_scene(scene_t scene) {
    while (scene.scene.begin() != scene.scene.end()) {
        scene.scene.pop_front();
    }
}

scene_t * init_OSMesa_context(scene_t * scene, int _width, int _height) {
    scene_t * r = scene;

    if ((width > 2048) || (height > 2048)) {
        printf("Image too wide!\n");
        return NULL;
    }
      
    if (!r)
        r = new scene_t();
    
    glPushAttrib(GL_ALL_ATTRIB_BITS);
    
    if ((width == _width) && (height == _height)) {
        return r;
    }
  
    width = _width;
    height = _height;
    
    /* Bind the buffer to the context and make it current */
    if (!OSMesaMakeCurrent(ctx, buffer, GL_UNSIGNED_BYTE, width, height)) {
        printf("OSMesaMakeCurrent (8 bits/channel) failed!\n");
        delete r;
        return NULL;
    }
    return r;
}

void init_OSMesa() {
    const GLint z = 32, stencil = 0, accum = 0;

    ctx = OSMesaCreateContextExt(OSMESA_BGRA, z, stencil, accum, NULL);
    if (!ctx) {
        printf("OSMesaCreateContextExt() failed!\n");
        return;
    }
    
    buffer = malloc(2048 * 2048 * 4);

    if (!buffer) {
        printf("Alloc image buffer failed!\n");
        return;
    }
    
    delete init_OSMesa_context(0, 300, 300);
    glPopAttrib();
}

void flip_scene(scene_t * scene, const char * buffer, int width, int height, bool upscale) {
    /* Make sure buffered commands are finished! */
    glFinish();

    Magick::Image i(width, height, "BGRA", Magick::CharPixel, buffer);
    i.flip();
    i.animationDelay(6);
    i.opacity(0);

    if (upscale) {
        i.resize(Magick::Geometry(width / 2, height / 2));
    }
    
    scene->scene.push_back(i);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
}

void * dump_scene_threaded(void * arg) {
    scene_t * scene = (scene_t *) arg;
    char fname[2049];

    writeImages(scene->scene.begin(), scene->scene.end(), scene->tmp_filename.to_charp());
    unlink(scene->filename.to_charp());
    rename(scene->tmp_filename.to_charp(), scene->filename.to_charp());
    delete scene;
    pthread_exit(0);
}

void dump_scene(scene_t * scene, const String & filename, Handle * out, const char * buffer, int width, int height, bool upscale) {
    if (scene->scene.begin() == scene->scene.end())
        flip_scene(scene, buffer, width, height, upscale);

    if (out) {
        Magick::Blob b;
        scene->scene.begin()->magick("JPEG");
        scene->scene.begin()->quality(95);
        writeImages(scene->scene.begin(), scene->scene.end(), &b);
        out->write(b.data(), b.length());
        delete scene;
    } else {
        pthread_t thread;
        scene->filename = filename;
        scene->tmp_filename = "tmp-" + filename;
        if (pthread_create(&thread, NULL, dump_scene_threaded, scene) == 0) {
            pthread_detach(thread);
        }
    }
    
    glPopAttrib();

    return;
}

class plugin_osmesa : public Base {
};

class Luaplugin_osmesa : public LuaObject {
  public:
    static void pushstatics(Lua *) throw (GeneralException);
  protected:
    virtual void pushmembers(Lua *);
};

enum plugin_osmesa_functions_t {
    PLUGIN_OSMESA_INITOSMESA,
    PLUGIN_OSMESA_FLIPSCENE,
    PLUGIN_OSMESA_DUMPSCENE,
    PLUGIN_OSMESA_LOADTEX,
};

struct lua_functypes_t plugin_osmesa_functions[] = {
    { PLUGIN_OSMESA_INITOSMESA,    "InitOSMesa",       3, 4, { BLUA_USERDATA | BLUA_NIL, BLUA_NUMBER, BLUA_NUMBER, BLUA_BOOLEAN } },
    { PLUGIN_OSMESA_FLIPSCENE,     "FlipScene",        1, 1, { BLUA_USERDATA } },
    { PLUGIN_OSMESA_DUMPSCENE,     "DumpScene",        2, 2, { BLUA_USERDATA, BLUA_STRING | BLUA_OBJECT } },
    { PLUGIN_OSMESA_LOADTEX,       "LoadTex",          1, 1, { BLUA_STRING } },
    { -1, 0, 0, 0, 0 }
};

class sLua_plugin_osmesa : public Base {
  public:
    DECLARE_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_INITOSMESA);
    DECLARE_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_FLIPSCENE);
    DECLARE_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_DUMPSCENE);
    DECLARE_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_LOADTEX);
  private:
    static int plugin_osmesa_proceed(Lua * L, int n, plugin_osmesa * obj, int caller);
    static int plugin_osmesa_proceed_statics(Lua * L, int n, int caller);
};
void Luaplugin_osmesa::pushmembers(Lua * L) { }

void Luaplugin_osmesa::pushstatics(Lua * L) throw (GeneralException) {
    //CHECK_METHODS(plugin_osmesa);
    CHECK_FUNCTIONS(plugin_osmesa);

    PUSH_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_INITOSMESA);
    PUSH_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_FLIPSCENE);
    PUSH_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_DUMPSCENE);
    PUSH_FUNCTION(plugin_osmesa, PLUGIN_OSMESA_LOADTEX);
}

int sLua_plugin_osmesa::plugin_osmesa_proceed(Lua * L, int n, plugin_osmesa * obj, int caller) {
    return 0;
}

int sLua_plugin_osmesa::plugin_osmesa_proceed_statics(Lua * L, int n, int caller) {
    int _width, _height, r = 0;
    String filename;
    const char * t;
    DDS_IMAGE_DATA * dds;
    scene_t * scene = 0;

    switch (caller) {
    case PLUGIN_OSMESA_INITOSMESA:
        if (!L->isnil(1)) {
            scene = (scene_t *) L->touserdata(1);
        }
        _width = L->tonumber(2);
        _height = L->tonumber(3);
        if (n == 4) {
            upscale = L->toboolean(4);
        } else {
            upscale = false;
        }
        L->push(init_OSMesa_context(scene, _width, _height));
        r = 1;
        break;
    case PLUGIN_OSMESA_FLIPSCENE:
        flip_scene((scene_t *) L->touserdata(1), (char *) buffer, width, height, upscale);
        break;
    case PLUGIN_OSMESA_DUMPSCENE:
        if (L->isstring(2)) {
            filename = L->tostring(2);
            dump_scene((scene_t *) L->touserdata(1), filename, 0, (char *) buffer, width, height, upscale);
        } else {
            Handle * t = (Handle *) LuaObject::getme(L, 2);
            dump_scene((scene_t *) L->touserdata(1), "", t, (char *) buffer, width, height, upscale);
        }
        break;
    case PLUGIN_OSMESA_LOADTEX:
        filename = L->tostring(1);
        t = filename.to_charp();
        dds = loadDDSTextureFile(t);
        L->push((lua_Number) loadCompressedTexture(dds));
        L->push((lua_Number) dds->width);
        L->push((lua_Number) dds->height);
        destroyDDS(dds);
        r = 3;
        break;
    }
    
    return r;
}

static void _init_plugin(Lua * L) {
    init_OSMesa();
    Luaplugin_osmesa::pushstatics(L);
}

extern "C" {
    
WEAK void init_plugin(Lua * L) {
    _init_plugin(L);
}

void luaosmesa_init(Lua * L) {
    _init_plugin(L);
}
    
}