const serviceMap = new Map();

async function getServices() {
	const url = "api/services";
	try {
		const response = await fetch(url);
		if (!response.ok) {
			throw new Error(`Response status: ${response.status}`);
		}

		const json = await response.json();
		return json;
	} catch (error) {
		console.error(error.message);
	}
}

function updateStatus() {
	const statusElm = document.getElementById("status");
	const issuesElm = document.getElementById("issues");
	const issues = [...serviceMap.values()].filter((s) => !s).length;
	issuesElm.textContent = `${issues} issue(s) detected`;
	if (issues) {
		statusElm.setAttribute("class", "error");
	} else {
		statusElm.setAttribute("class", "ok");
	}
}

function updateService(name, node, status) {
	switch (status.status) {
		case "pass":
			node.textContent = "Operational";
			node.setAttribute("class", "ok");
			break;
		case "fail":
			node.textContent = "Down";
			node.title = status.output;
			node.setAttribute("class", "error");
			break;
		case "warn":
			node.textContent = "Warning";
			node.title = status.output;
			node.setAttribute("class", "warning");
			break;
		case "unknown":
			node.textContent = "Unknown";
			node.setAttribute("class", "warning");
	}

	serviceMap.set(name, status.status === "pass");
	updateStatus();
}

getServices().then((services) => {
	for (const [service] of Object.entries(services)) {
		const table = document.getElementById("services");
		const row = table.insertRow();
		const nameNode = row.insertCell();
		nameNode.textContent = service;
		const node = row.insertCell();

		const evtSource = new EventSource(`sse/${service}`);
		evtSource.onmessage = (event) => {
			const status = JSON.parse(event.data);
			updateService(service, node, status);
		};
	}
});