#pragma once

#include <stdlib.h>
#include <string>
#include <stdexcept>

/** file on the desktop (posix) filesystem */
class DataSourcePosixFile {

	FILE* f = nullptr;

public:

	DataSourcePosixFile() {

	}

	DataSourcePosixFile(const char* file) {
		f = fopen(file, "rw");
		if (!f) {
			throw std::runtime_error(std::string("failed to open file: ") + file);
		}
	}

	~DataSourcePosixFile() {
		if (f) {fclose(f);}
	}

	uint32_t curPos() const {
		return ftell(f);
	}

	void seekTo(uint32_t pos) {
		fseek(f, pos, SEEK_SET);
	}

	uint32_t read(uint32_t bytes, uint8_t* dst) {
		return fread(dst, bytes, 1, f) * bytes;
	}

	uint32_t write(uint32_t bytes, const uint8_t* src) {
		return fwrite(src, bytes, 1, f) * bytes;
	}
	
	/** read an entity */
	template <typename T> void readType(T& dst) {
		read(sizeof(T), (uint8_t*) &dst);
	}

};