// Copyright (c) 2012- PPSSPP Project.

// 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, version 2.0 or later versions.

// 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 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.

#pragma once

// TODO: Remove the Windows-specific code, FILE is fine there too.

#include <map>

#include "Common/File/Path.h"
#include "Core/FileSystems/FileSystem.h"
#include "Core/FileSystems/DirectoryFileSystem.h"

extern const std::string INDEX_FILENAME;

class VirtualDiscFileSystem: public IFileSystem {
public:
	VirtualDiscFileSystem(IHandleAllocator *_hAlloc, const Path &_basePath);
	~VirtualDiscFileSystem();

	void DoState(PointerWrap &p) override;
	int      OpenFile(std::string filename, FileAccess access, const char *devicename = nullptr) override;
	size_t   SeekFile(u32 handle, s32 position, FileMove type) override;
	size_t   ReadFile(u32 handle, u8 *pointer, s64 size) override;
	size_t   ReadFile(u32 handle, u8 *pointer, s64 size, int &usec) override;
	void     CloseFile(u32 handle) override;
	PSPFileInfo GetFileInfo(std::string filename) override;
	PSPFileInfo GetFileInfoByHandle(u32 handle) override;
	bool     OwnsHandle(u32 handle) override;
	int      Ioctl(u32 handle, u32 cmd, u32 indataPtr, u32 inlen, u32 outdataPtr, u32 outlen, int &usec) override;
	PSPDevType DevType(u32 handle) override;
	std::vector<PSPFileInfo> GetDirListing(std::string_view path, bool *exists = nullptr) override;
	FileSystemFlags Flags() const override { return FileSystemFlags::UMD; }
	u64  FreeDiskSpace(const std::string &path) override { return 0; }

	// unsupported operations
	size_t  WriteFile(u32 handle, const u8 *pointer, s64 size) override;
	size_t  WriteFile(u32 handle, const u8 *pointer, s64 size, int &usec) override;
	bool MkDir(const std::string &dirname) override;
	bool RmDir(const std::string &dirname) override;
	int  RenameFile(const std::string &from, const std::string &to) override;
	bool RemoveFile(const std::string &filename) override;

	bool ComputeRecursiveDirSizeIfFast(const std::string &path, int64_t *size) override { return false; }

	void Describe(char *buf, size_t size) const override { snprintf(buf, size, "VirtualDisc: %s", basePath.ToVisualString().c_str()); }  // TODO: Ask the fileLoader about the origins

private:
	void LoadFileListIndex();
	// Warning: modifies input string.
	int getFileListIndex(std::string &fileName);
	int getFileListIndex(u32 accessBlock, u32 accessSize, bool blockMode = false) const;
	Path GetLocalPath(std::string_view localpath) const;

	typedef enum { VFILETYPE_NORMAL, VFILETYPE_LBN, VFILETYPE_ISO } VirtualFileType;

	struct OpenFileEntry {
		OpenFileEntry() {}
		OpenFileEntry(FileSystemFlags fileSystemFlags) {
			hFile = DirectoryFileHandle(DirectoryFileHandle::SKIP_REPLAY, fileSystemFlags);
		}

		DirectoryFileHandle hFile;
		VirtualFileType type = VFILETYPE_NORMAL;
		u32 fileIndex = 0;
		u64 curOffset = 0;
		u64 startOffset = 0;	// only used by lbn files
		u64 size = 0;			// only used by lbn files

		bool Open(const Path &basePath, std::string& fileName, FileAccess access) {
			// Ignored, we're read only.
			u32 err;
			return hFile.Open(basePath, fileName, access, err);
		}
		size_t Read(u8 *data, s64 size) {
			return hFile.Read(data, size);
		}
		size_t Seek(s32 position, FileMove type) {
			return hFile.Seek(position, type);
		}
		void Close() {
			return hFile.Close();
		}
	};

	typedef std::map<u32, OpenFileEntry> EntryMap;

	EntryMap entries;
	IHandleAllocator *hAlloc;
	Path basePath;

	struct FileListEntry {
		std::string fileName;
		u32 firstBlock;
		u32 totalSize;
	};

	std::vector<FileListEntry> fileList;
	u32 currentBlockIndex;
	u32 lastReadBlock_;
};