#include <iostream>
#include <fstream>
#include <cpr/cpr.h>

#include "DownloadManager.h"

DownloadManager::DownloadManager() { }

DownloadManager::~DownloadManager() {
	for (std::thread* download : download_queue) {
		download->join();
		delete download;
		download = nullptr;
	}
}

std::fstream* DownloadManager::open_file(std::string filename) {
	while (this->file_queue.size() > this->max_files);
	std::fstream* out = nullptr;
	do {
		delete out;
		out = new std::fstream(filename, std::ios::out | std::ios::binary);
	} while (!out->is_open());
	this->file_queue.push_back(out);
	return out;
}

void DownloadManager::close_file(std::fstream* file_ptr) {
	file_ptr->close();
	delete file_ptr;
	this->file_queue.erase(std::remove(this->file_queue.begin(), this->file_queue.end(), file_ptr));
}

std::thread* DownloadManager::wget(std::string url, std::string filename) {
	std::thread* download = new std::thread([url, filename, this] {
		cpr::Response res;
		do res = cpr::Get(cpr::Url{url});
		while (res.status_code != 200);

		std::fstream* file = this->open_file(filename);
		file->write(res.text.data(), res.downloaded_bytes); // can't use << for binary data
		this->close_file(file);
	});
	download_queue.push_back(download);
	return download;
}