let params;
let cur_seconds = null;
let timer_id;
let cd;

const page = document.getElementById("page");

function setupCountdown() {
	var prompt_text = "";
	var progress_bar = "";
	params = new URLSearchParams(document.location.search);
	for ([key, value] of params.entries()) {
		console.log(`${key}: ${value}`);
	}

	switch (params.get("cdstyle")) {
		case "labeled_bar":
			let label_text = params.get("label_text");
			prompt_text = `<div id="prompt">${label_text}</div>`;
			progress_bar = `<div id="bar"><div id="progress"></div></div>`;
			break;
		case "bar":
			progress_bar = `<div id="bar"><div id="progress"></div></div>`;
			break;
	}
	page_template = `
		${prompt_text}
		${progress_bar}
		<div id="countdown">
			<div id="minutes">00</div>
			<div id="separator">:</div>
			<div id="seconds">00</div>
		</div>
	`;
	page.innerHTML = page_template;
	cd = document.getElementById("countdown");
	let prompt = document.getElementById("prompt");
	cur_seconds = parseInt(params.get("duration"));

	if (params.get("f_family") !== "") {
		cd.style.fontFamily = params.get("f_family");
		if (prompt) {
			document.getElementById("prompt").style.fontFamily = params.get("f_family");
		}
	}
	cd.style.color = params.get("f_color");
	if (document.getElementById("progress")) {
		document.getElementById("progress").style.backgroundColor = params.get("b_color");
	}

	draw();
	timer_id = window.setInterval(tick, 1000);
}

function tick() {
	if (cur_seconds == 0) {
		while (cd.firstChild) {
			cd.removeChild(cd.firstChild);
		}
		let end_msg = document.createElement("div");
		end_msg.id = "endmsg";
		end_msg.textContent = params.get("end_text");
		cd.appendChild(end_msg);
		window.clearInterval(timer_id);
		return;
	}
	cur_seconds--;
	draw();
}

function draw() {
	if (document.getElementById("progress")) {
		draw_bar();
	}
	document.getElementById("minutes").textContent = zero_pad(Math.floor(cur_seconds / 60));
	document.getElementById("seconds").textContent = zero_pad((cur_seconds % 60));
}

function draw_bar() {
	document.getElementById("progress").style.width = (((params.get("duration") - cur_seconds) / params.get("duration")) * 100) + "%";
}

function zero_pad(num) {
	if (num < 10) {
		return "0"+num;
	} else {
		return num;
	}
}