// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.

#include <algorithm>
#include <cstring>
#include <string>
#include <utility>
#include <SOIL/SOIL.h>

#include "Common/CommonPaths.h"
#include "Common/FileSearch.h"
#include "Common/FileUtil.h"
#include "Common/StringUtil.h"

#include "Core/ConfigManager.h"

#include "VideoCommon/HiresTextures.h"
#include "VideoCommon/VideoConfig.h"

std::unordered_map<std::string, std::string> HiresTexture::textureMap;

void HiresTexture::Init(const std::string& gameCode)
{
	textureMap.clear();

	CFileSearch::XStringVector Directories;

	std::string szDir = StringFromFormat("%s%s", File::GetUserPath(D_HIRESTEXTURES_IDX).c_str(), gameCode.c_str());
	Directories.push_back(szDir);

	for (u32 i = 0; i < Directories.size(); i++)
	{
		File::FSTEntry FST_Temp;
		File::ScanDirectoryTree(Directories[i], FST_Temp);
		for (auto& entry : FST_Temp.children)
		{
			if (entry.isDirectory)
			{
				bool duplicate = false;

				for (auto& Directory : Directories)
				{
					if (Directory == entry.physicalName)
					{
						duplicate = true;
						break;
					}
				}

				if (!duplicate)
					Directories.push_back(entry.physicalName);
			}
		}
	}

	CFileSearch::XStringVector Extensions = {
		"*.png",
		"*.bmp",
		"*.tga",
		"*.dds",
		"*.jpg" // Why not? Could be useful for large photo-like textures
	};

	CFileSearch FileSearch(Extensions, Directories);
	const CFileSearch::XStringVector& rFilenames = FileSearch.GetFileNames();

	const std::string code = StringFromFormat("%s_", gameCode.c_str());

	if (rFilenames.size() > 0)
	{
		for (auto& rFilename : rFilenames)
		{
			std::string FileName;
			SplitPath(rFilename, nullptr, &FileName, nullptr);

			if (FileName.substr(0, code.length()).compare(code) == 0 && textureMap.find(FileName) == textureMap.end())
				textureMap.insert(std::map<std::string, std::string>::value_type(FileName, rFilename));
		}
	}
}

std::string HiresTexture::GenBaseName(const u8* texture, size_t texture_size, const u8* tlut, size_t tlut_size, u32 width, u32 height, int format)
{
	u64 tex_hash = GetHashHiresTexture(texture, (int)texture_size, g_ActiveConfig.iSafeTextureCache_ColorSamples);
	u64 tlut_hash = 0;
	u64 hash = tex_hash;
	if (tlut_size)
	{
		tlut_hash = GetHashHiresTexture(tlut, (int)tlut_size, g_ActiveConfig.iSafeTextureCache_ColorSamples);
		hash ^= tlut_hash;
	}
	return StringFromFormat("%s_%08x_%i", SConfig::GetInstance().m_LocalCoreStartupParameter.m_strUniqueID.c_str(), (u32)hash, (u16)format);
}

HiresTexture* HiresTexture::Search(const u8* texture, size_t texture_size, const u8* tlut, size_t tlut_size, u32 width, u32 height, int format)
{
	std::string base_filename = GenBaseName(texture, texture_size, tlut, tlut_size, width, height, format);

	HiresTexture* ret = nullptr;
	for (int level = 0;; level++)
	{
		std::string filename = base_filename;
		if (level)
		{
			filename += StringFromFormat("_mip%u", level);
		}

		if (textureMap.find(filename) != textureMap.end())
		{
			Level l;

			File::IOFile file;
			file.Open(textureMap[filename], "rb");
			std::vector<u8> buffer(file.GetSize());
			file.ReadBytes(buffer.data(), file.GetSize());

			int channels;
			l.data = SOIL_load_image_from_memory(buffer.data(), (int)buffer.size(), (int*)&l.width, (int*)&l.height, &channels, SOIL_LOAD_RGBA);
			l.data_size = (size_t)l.width * l.height * 4;

			if (l.data == nullptr)
			{
				ERROR_LOG(VIDEO, "Custom texture %s failed to load", filename.c_str());
				break;
			}

			if (!level)
			{
				if (l.width * height != l.height * width)
					ERROR_LOG(VIDEO, "Invalid custom texture size %dx%d for texture %s. The aspect differs from the native size %dx%d.",
					          l.width, l.height, filename.c_str(), width, height);
				if (l.width % width || l.height % height)
					WARN_LOG(VIDEO, "Invalid custom texture size %dx%d for texture %s. Please use an integer upscaling factor based on the native size %dx%d.",
					         l.width, l.height, filename.c_str(), width, height);
				width = l.width;
				height = l.height;
			}
			else if (width != l.width || height != l.height)
			{
				ERROR_LOG(VIDEO, "Invalid custom texture size %dx%d for texture %s. This mipmap layer _must_ be %dx%d.",
				          l.width, l.height, filename.c_str(), width, height);
				SOIL_free_image_data(l.data);
				break;
			}

			// calculate the size of the next mipmap
			width >>= 1;
			height >>= 1;

			if (!ret)
				ret = new HiresTexture();
			ret->m_levels.push_back(l);
		}
		else
		{
			break;
		}
	}

	return ret;
}

HiresTexture::~HiresTexture()
{
	for (auto& l : m_levels)
	{
		SOIL_free_image_data(l.data);
	}
}