var fs = require("fs");
var pathlib = require("path");

var mimes = {
	txt: "text/plain",
	css: "text/css",
	html: "text/html",

	js: "application/javascript",
	json: "application/json",
	xml: "application/xml",
	zip: "application/zip",
	pdf: "application/pdf",

	png: "image/png",
	jpeg: "image/jpeg",
	jpg: "image/jpeg",
	gif: "image/gif",
	svg: "image/svg",
}

function mimetype(path) {
	var unknown = "application/octet-stream";

	var ext = pathlib.extname(path);
	if (ext)
		return mimes[ext.substr(1)] || unknown;
	else
		return unknown;
}

function sendfile(path, app, pathname, res) {
	fs.open(path, "r", (err, fd) => {
		if (err) {
			app.notice(err);
			res.writeHead(404);
			res.end(app.template(app.res404, { pathname: pathname }));
			return;
		}

		res.writeHead(200, {
			"Content-Type": mimetype(path)
		});

		var rs = fs.createReadStream(null, { fd: fd });
		rs.on("error", err => {
			app.warning(err);
		});
		rs.on("data", d => res.write(d));
		rs.on("end", () => res.end());
	});
}

module.exports = function(root, before) {

	return function(req, res, app) {
		var pn = req.urlobj.pathname;

		// Send a file
		function send(path) {
			sendfile(path, app, pn, res);
		}

		// Prevent leaking information
		if (pn.indexOf("../") !== -1 || pn.indexOf("/..") !== -1 || pn === "..") {
			res.writeHead(403);
			res.end(app.template(app.res403, { pathname: pn }));
			return;
		}

		// Join the web root with the request's path name
		var path = pathlib.join(root, pn.replace(before, ""));

		fs.stat(path, (err, stat) => {

			// If there's an error stat'ing, just error
			if (err) {
				app.notice(err);
				res.writeHead(404);
				res.end(app.template(app.res404, { pathname: pn }));
				return;
			}

			// If it's a directory, we want the index.html file
			if (stat.isDirectory())
				path = pathlib.join(path, "index.html");

			// Send the file
			send(path);
		});
	}
}