let WebDAV = {};

WebDAV.normAddress = function(path){
	return settings.webdavAddress.replace(/\/$/, "");
}
WebDAV.makePath = function(path){
	if(typeof(path) !== "string")
		path = path.join("/");
	return [ WebDAV.normAddress(), path ].join("/");
}
WebDAV.req = function(path, type, opts){
	path = WebDAV.makePath(path);
	opts = opts ?? {};
	opts.method = type;
	opts.headers = {
		Authorization: "Basic " + btoa(`${settings.webdavUsername}:${settings.webdavPassword}`),
	};
	return fetch(path, opts);
}
WebDAV.mkcol = async (path, opts) => WebDAV.req(path, "MKCOL", opts);
WebDAV.get = async (path, opts) => WebDAV.req(path, "GET", opts);
WebDAV.put = async (path, body, opts) => {
	opts = opts ?? {};
	opts.body = body;
	return WebDAV.req(path, "PUT", opts);
}
WebDAV.propfind = async (path, opts) => {
	let res = await WebDAV.req(path, "PROPFIND", opts);
	let xmlText = await res.text();
	let parser = new DOMParser();
	let xmlDoc = parser.parseFromString(xmlText, "text/xml");

	let responses = xmlDoc.getElementsByTagName("D:response");

	let items = Array.from(responses).map(response => {
		let href = response.getElementsByTagName("D:href")[0].textContent;
		let propstat = response.getElementsByTagName("D:propstat")[0];
		let lastModified = propstat.getElementsByTagName("D:lastmodified")[0].textContent;
		return { href, lastModified };
	});

	return items;
}

WebDAV.listAllFiles = async function(){
	let files = [];
	for(file of await WebDAV.propfind([])){
		if(!file.href.endsWith(".json"))
			continue;
		let id = file.href.split("/").pop().replace(/\.json$/, "")
		let lastModified = parseInt(file.lastModified);
		files.push({ id, lastModified });
	}
	return files;
}
WebDAV.loadFile = async function(id){
	let info = await (await WebDAV.get(`${id}.json`)).json();
	let file = File(info.id);
	file.changeInfo(info);
	file.save();
}
WebDAV.loadAllFiles = async function(){
	for({ id, lastModified } of await WebDAV.listAllFiles()){
		try {
			let file = await File.load(id);
			console.log(file.info, lastModified)
			if(file.info.lastModified && file.info.lastModified >= lastModified){
				console.log("Skipping newer file", id)
				continue;
			}
			console.log("Pulling outdated file", id)
		} catch(exc){
			console.log("Pulling unknown file", id)
		}
		await WebDAV.loadFile(id);
	}
}
WebDAV.putFile = async function(info){
	WebDAV.put(`${info.id}.json`, JSON.stringify(info));
}
WebDAV.putAllFiles = async function(){
	for(file of await File.loadAll())
		await WebDAV.putFile(file.info);
}

WebDAV.init = async function(){
	if(!settings.webdavAddress)
		return;
	await WebDAV.mkcol([]);
}