// Copyright 2024 The DMBMX2Tools Authors
// SPDX-License-Identifier: MIT

#include <base/io/FileStream.hpp>
#include <cstdio>

namespace dmtools::io {

	constexpr auto DmToLibc(StreamSeekDirection dir) {
		using enum StreamSeekDirection;
		switch(dir) {
			case Beg: return SEEK_SET;
			case Cur: return SEEK_CUR;
			case End: return SEEK_END;
			default: return SEEK_SET;
		}
	}

	constexpr auto DmOpenMode(FileStream::OpenMode mode) {
		using enum FileStream::OpenMode;
		switch(mode) {
			case Read: return "rb";
			case ReadWrite: return "wb+";
		}
	}

	FileStream::~FileStream() {
		Close();
	}

	bool FileStream::Open(const std::string& filename, OpenMode mode) {
		file = std::fopen(filename.c_str(), DmOpenMode(mode));
		return Ok();
	}

	void FileStream::Flush() {
		fflush(static_cast<std::FILE*>(file));
	}

	void FileStream::Close() {
		if(Ok()) {
			fclose(static_cast<std::FILE*>(file));
		}
	}

	StreamDiff FileStream::ReadSome(u8* buffer, usize length) {
		if(Ok())
			return std::fread(static_cast<u8*>(buffer), 1, length, static_cast<std::FILE*>(file));
		return -1;
	}

	StreamDiff FileStream::WriteSome(const u8* buffer, usize length) {
		if(Ok())
			return std::fwrite(static_cast<const void*>(buffer), length, 1, static_cast<std::FILE*>(file));
		return -1;
	}

	StreamDiff FileStream::Seek(StreamDiff where, StreamSeekDirection dir) {
		if(!Ok())
			return -1;

#ifdef __GLIBC__
		return fseeko64(static_cast<std::FILE*>(file), where, DmToLibc(dir));
#else
		return fseek(static_cast<std::FILE*>(file), where, DmToLibc(dir));
#endif
	}

	StreamDiff FileStream::Tell() const {
		if(!Ok())
			return -1;
#ifdef __GLIBC__
		return ftello64(static_cast<std::FILE*>(file));
#else
		return ftell(static_cast<std::FILE*>(file));
#endif
	}

	bool FileStream::Ok() const {
		return file != nullptr;
	}

	bool FileStream::Eof() const {
		if(!Ok())
			return true;

		return feof(static_cast<std::FILE*>(file));
	}

} // namespace dmtools::io