/*
 * Modern effects for a modern Streamer
 * Copyright (C) 2017 Michael Fabian Dirks
 *
 * This program 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
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include "gs-texture.h"
#include <fstream>
#include <stdexcept>
#include <sys/stat.h>
#include "util-math.h"

extern "C" {
#pragma warning(push)
#pragma warning(disable : 4201)
#include <obs.h>
#include <util/platform.h>
#pragma warning(pop)
}

gs::texture::texture(uint32_t width, uint32_t height, gs_color_format format, uint32_t mip_levels,
					 const uint8_t** mip_data, gs::texture::flags texture_flags)
{
	if (width == 0)
		throw std::logic_error("width must be at least 1");
	if (height == 0)
		throw std::logic_error("height must be at least 1");
	if (mip_levels == 0)
		throw std::logic_error("mip_levels must be at least 1");
	if (!mip_data)
		throw std::logic_error("mip_data is invalid");

	if (mip_levels > 1 || ((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps)) {
		bool isPOT = util::math::is_power_of_two(width) && util::math::is_power_of_two(height);
		if (!isPOT)
			throw std::logic_error("mip mapping requires power of two dimensions");
	}

	obs_enter_graphics();
	m_texture = gs_texture_create(
		width, height, format, mip_levels, mip_data,
		(((texture_flags & flags::Dynamic) == flags::Dynamic) ? GS_DYNAMIC : 0)
			| (((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps) ? GS_BUILD_MIPMAPS : 0));
	obs_leave_graphics();

	if (!m_texture)
		throw std::runtime_error("Failed to create texture.");

	m_textureType = type::Normal;
}

gs::texture::texture(uint32_t width, uint32_t height, uint32_t depth, gs_color_format format, uint32_t mip_levels,
					 const uint8_t** mip_data, gs::texture::flags texture_flags)
{
	if (width == 0)
		throw std::logic_error("width must be at least 1");
	if (height == 0)
		throw std::logic_error("height must be at least 1");
	if (depth == 0)
		throw std::logic_error("depth must be at least 1");
	if (mip_levels == 0)
		throw std::logic_error("mip_levels must be at least 1");
	if (!mip_data)
		throw std::logic_error("mip_data is invalid");

	if (mip_levels > 1 || ((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps)) {
		bool isPOT = (pow(2, (int64_t)floor(log(width) / log(2))) == width)
					 && (pow(2, (int64_t)floor(log(height) / log(2))) == height)
					 && (pow(2, (int64_t)floor(log(depth) / log(2))) == depth);
		if (!isPOT)
			throw std::logic_error("mip mapping requires power of two dimensions");
	}

	obs_enter_graphics();
	m_texture = gs_voltexture_create(
		width, height, depth, format, mip_levels, mip_data,
		(((texture_flags & flags::Dynamic) == flags::Dynamic) ? GS_DYNAMIC : 0)
			| (((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps) ? GS_BUILD_MIPMAPS : 0));
	obs_leave_graphics();

	if (!m_texture)
		throw std::runtime_error("Failed to create texture.");

	m_textureType = type::Volume;
}

gs::texture::texture(uint32_t size, gs_color_format format, uint32_t mip_levels, const uint8_t** mip_data,
					 gs::texture::flags texture_flags)
{
	if (size == 0)
		throw std::logic_error("size must be at least 1");
	if (mip_levels == 0)
		throw std::logic_error("mip_levels must be at least 1");
	if (!mip_data)
		throw std::logic_error("mip_data is invalid");

	if (mip_levels > 1 || ((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps)) {
		bool isPOT = (pow(2, (int64_t)floor(log(size) / log(2))) == size);
		if (!isPOT)
			throw std::logic_error("mip mapping requires power of two dimensions");
	}

	obs_enter_graphics();
	m_texture = gs_cubetexture_create(
		size, format, mip_levels, mip_data,
		(((texture_flags & flags::Dynamic) == flags::Dynamic) ? GS_DYNAMIC : 0)
			| (((texture_flags & flags::BuildMipMaps) == flags::BuildMipMaps) ? GS_BUILD_MIPMAPS : 0));
	obs_leave_graphics();

	if (!m_texture)
		throw std::runtime_error("Failed to create texture.");

	m_textureType = type::Cube;
}

gs::texture::texture(std::string file)
{
	struct stat st;
	if (os_stat(file.c_str(), &st) != 0)
		throw std::ios_base::failure(file);

	obs_enter_graphics();
	m_texture = gs_texture_create_from_file(file.c_str());
	obs_leave_graphics();

	if (!m_texture)
		throw std::runtime_error("Failed to load texture.");
}

gs::texture::~texture()
{
	if (m_isOwner && m_texture) {
		obs_enter_graphics();
		switch (gs_get_texture_type(m_texture)) {
		case GS_TEXTURE_2D:
			gs_texture_destroy(m_texture);
			break;
		case GS_TEXTURE_3D:
			gs_voltexture_destroy(m_texture);
			break;
		case GS_TEXTURE_CUBE:
			gs_cubetexture_destroy(m_texture);
			break;
		}
		obs_leave_graphics();
	}
	m_texture = nullptr;
}

void gs::texture::load(int unit)
{
	obs_enter_graphics();
	gs_load_texture(m_texture, unit);
	obs_leave_graphics();
}

gs_texture_t* gs::texture::get_object()
{
	return m_texture;
}

uint32_t gs::texture::get_width()
{
	switch (m_textureType) {
	case type::Normal:
		return gs_texture_get_width(m_texture);
	case type::Volume:
		return gs_voltexture_get_width(m_texture);
	case type::Cube:
		return gs_cubetexture_get_size(m_texture);
	}
	return 0;
}

uint32_t gs::texture::get_height()
{
	switch (m_textureType) {
	case type::Normal:
		return gs_texture_get_height(m_texture);
	case type::Volume:
		return gs_voltexture_get_height(m_texture);
	case type::Cube:
		return gs_cubetexture_get_size(m_texture);
	}
	return 0;
}

uint32_t gs::texture::get_depth()
{
	switch (m_textureType) {
	case type::Normal:
		return 1;
	case type::Volume:
		return gs_voltexture_get_depth(m_texture);
	case type::Cube:
		return 6;
	}
	return 0;
}

gs::texture::type gs::texture::get_type()
{
	return m_textureType;
}

gs_color_format gs::texture::get_color_format()
{
	return gs_texture_get_color_format(m_texture);
}