//
// Lol Engine
//
// Copyright: (c) 2010-2014 Sam Hocevar <sam@hocevar.net>
//   This program is free software; you can redistribute it and/or
//   modify it under the terms of the Do What The Fuck You Want To
//   Public License, Version 2, as published by Sam Hocevar. See
//   http://www.wtfpl.net/ for more details.
//

#if defined HAVE_CONFIG_H
#   include "config.h"
#endif

#include "core.h"
#include "image-private.h"

namespace lol
{

/* HACK: We cannot make this an ImageLoader member function, because the
 * REGISTER_IMAGE_CODEC macro forward-declares free functions from
 * the "lol" namespace. An apparent bug in Visual Studio's compiler
 * makes it think these functions are actually in the top-level
 * namespace when the forward declaration is in a class member function.
 * To avoid the problem, we make the forward declaration in a free
 * function.
 * The bug was reported to Microsoft and fixed by them, but the fix
 * is not yet available.
 * https://connect.microsoft.com/VisualStudio/feedback/details/730878/ */
static bool RegisterAllCodecs(Array<ImageCodec *> &codeclist)
{
#if defined __ANDROID__
    REGISTER_IMAGE_CODEC(AndroidImageCodec)
#endif
    REGISTER_IMAGE_CODEC(DummyImageCodec)
#if defined USE_GDIPLUS
    REGISTER_IMAGE_CODEC(GdiPlusImageCodec)
#endif
#if defined __APPLE__ && defined __MACH__ && defined __arm__
    REGISTER_IMAGE_CODEC(IosImageCodec)
#endif
#if defined __CELLOS_LV2__
    REGISTER_IMAGE_CODEC(Ps3ImageCodec)
#endif
#if defined USE_SDL_IMAGE
    REGISTER_IMAGE_CODEC(SdlImageCodec)
#endif
    REGISTER_IMAGE_CODEC(ZedImageCodec)
    REGISTER_IMAGE_CODEC(ZedPaletteImageCodec)
#if defined USE_IMLIB2
    REGISTER_IMAGE_CODEC(Imlib2ImageCodec)
#endif

    return true;
}

/*
 * Our static image loader
 */

static class ImageLoader
{
    friend class Image;

public:
    inline ImageLoader()
    {
        RegisterAllCodecs(m_codecs);
    }

private:
    Array<ImageCodec *> m_codecs;
    Map<String, Image *> m_images;
}
g_image_loader;

/*
 * Public Image class
 */

Image::Image()
  : m_data(new ImageData())
{
}

Image::Image(char const *path)
  : m_data(new ImageData())
{
    Load(path);
}

Image::Image(ivec2 size)
  : m_data(new ImageData())
{
    SetSize(size);
}

Image::Image (Image const &other)
  : m_data(new ImageData())
{
    ivec2 size = other.GetSize();
    PixelFormat fmt = other.GetFormat();

    SetSize(size);
    if (fmt != PixelFormat::Unknown)
    {
        SetFormat(fmt);
        void *psrc = other.m_data->m_pixels[(int)fmt];
        void *pdst = m_data->m_pixels[(int)fmt];
        memcpy(pdst, psrc, size.x * size.y * BytesPerPixel(fmt));
    }
}

Image & Image::operator =(Image other)
{
    /* Since the argument is passed by value, we’re assured it’s a new
     * object and we can safely swap our m_data pointers. */
    std::swap(m_data, other.m_data);
    return *this;
}

Image::~Image()
{
    for (int k : m_data->m_pixels.Keys())
    {
        delete[] (uint8_t *)m_data->m_pixels[k];
        m_data->m_pixels[k] = nullptr;
    }
    delete m_data;
}

bool Image::Load(char const *path)
{
    for (auto codec : g_image_loader.m_codecs)
        if (codec->Load(this, path))
            return true;
    return false;
}

bool Image::Save(char const *path)
{
    for (auto codec : g_image_loader.m_codecs)
        if (codec->Save(this, path))
            return true;
    return false;
}

ivec2 Image::GetSize() const
{
    return m_data->m_size;
}

void Image::SetSize(ivec2 size)
{
    if (m_data->m_size != size)
    {
        /* FIXME: delete data or resize it */
        if (m_data->m_format != PixelFormat::Unknown)
        {
            m_data->m_pixels.Remove((int)m_data->m_format);
        }
    }
    m_data->m_size = size;

    /* FIXME: don’t do this! It’s useless. */
    if (m_data->m_format != PixelFormat::Unknown)
    {
        Unlock(Lock<PixelFormat::RGBA_8>());
    }
}

/* Wrap-around mode for some operations */
WrapMode Image::GetWrapX() const
{
    return m_data->m_wrap_x;
}

WrapMode Image::GetWrapY() const
{
    return m_data->m_wrap_y;
}

void Image::SetWrap(WrapMode wrap_x, WrapMode wrap_y)
{
    m_data->m_wrap_x = wrap_x;
    m_data->m_wrap_y = wrap_y;
}

/* The Lock() method */
template<PixelFormat T> typename PixelType<T>::type *Image::Lock()
{
    SetFormat(T);

    return (typename PixelType<T>::type *)m_data->m_pixels[(int)T];
}

/* Explicit specialisations for the above template */
#define _T(T) template PixelType<T>::type *Image::Lock<T>()
_T(PixelFormat::Y_8);
_T(PixelFormat::RGB_8);
_T(PixelFormat::RGBA_8);
_T(PixelFormat::Y_F32);
_T(PixelFormat::RGB_F32);
_T(PixelFormat::RGBA_F32);
#undef _T

/* Special case for the "any" format: return the last active buffer */
template<> void *Image::Lock<PixelFormat::Unknown>()
{
    ASSERT(m_data->m_format != PixelFormat::Unknown);

    return m_data->m_pixels[(int)m_data->m_format];
}

void Image::Unlock(void const *pixels)
{
    ASSERT(m_data->m_pixels.HasKey((int)m_data->m_format));

    /* Ensure that the unlocked data is inside the buffer */
    uintptr_t start = (uintptr_t)m_data->m_pixels[(int)m_data->m_format];
    uintptr_t end = start + m_data->m_size.x * m_data->m_size.y
                                 * BytesPerPixel(m_data->m_format);

    ASSERT(start <= (uintptr_t)pixels);
    ASSERT((uintptr_t)pixels <= end);
}

bool Image::RetrieveTiles(Array<ivec2, ivec2>& tiles) const
{
    /* TODO: re-implement this */
    //return m_data->m_codecdata->RetrieveTiles(tiles);
    return false;
}

} /* namespace lol */