function toggleSettings() {
	const panel = document.getElementById("settings-panel");
	panel.style.display = panel.style.display === "block"
		? "none"
		: "block";
	if (panel.style.display === "block") {
		const username = document.getElementById("username");
		username.focus();
		username.selectionStart = username.selectionEnd = username.value
			.length;
	}
}

function toggleUsers() {
	const panel = document.getElementById("users-panel");
	panel.style.display = panel.style.display === "block"
		? "none"
		: "block";
}

function toggleTheme() {
	const currentTheme = document.documentElement.getAttribute(
		"data-theme",
	);
	const newTheme = currentTheme === "dark" ? "light" : "dark";
	document.documentElement.setAttribute("data-theme", newTheme);
	localStorage.setItem("theme", newTheme);
}

async function deleteMessage(messageId) {
	if (confirm("Delete this message?")) {
		try {
			const response = await fetch("/messages", {
				method: "DELETE",
				headers: {
					"Content-Type": "application/json",
				},
				body: JSON.stringify({ messageId: messageId }),
			});

			if (response.ok) {
				updateMessagesInPlace();
			} else {
				console.error("Failed to delete message");
			}
		} catch (error) {
			console.error("Error deleting message:", error);
		}
	}
}

async function updateMessagesInPlace() {
	lastMessageCount = await getMessageCount();
	const currentScrollLocation = getScrollLocation();
	loadMessages(true, currentScrollLocation);
}

function getScrollLocation() {
	const messagesDiv = document.getElementById("messages");
	return messagesDiv.scrollTop;
}

function setScrollLocation(height) {
	const messagesDiv = document.getElementById("messages");
	messagesDiv.scrollTop = height;
}

document.addEventListener("click", function (event) {
	const settingsPanel = document.getElementById("settings-panel");
	const settingsButton = document.querySelector(".settings-button");
	const usersPanel = document.getElementById("users-panel");
	const usersButton = document.querySelector(".users-button");

	if (
		!settingsPanel.contains(event.target) &&
		!settingsButton.contains(event.target)
	) {
		settingsPanel.style.display = "none";
	}

	if (
		!usersPanel.contains(event.target) &&
		!usersButton.contains(event.target)
	) {
		usersPanel.style.display = "none";
	}
});

document.addEventListener("keypress", function (event) {
	if (event.key === "Enter" && !event.shiftKey) {
		const settingsPanel = document.getElementById("settings-panel");
		const inputPanel = document.getElementById("message");
		if (settingsPanel.contains(event.target)) {
			setUsername();
		}
		if (inputPanel.contains(event.target)) {
			event.preventDefault();
			sendMessage();
		}
	}
});

document.addEventListener("input", function (_) {
	const msg = document.getElementById("message");
	msg.style.height = "auto";
	msg.style.height = (msg.scrollHeight) + "px";
});

document.addEventListener("blur", function (_) {
	const msg = document.getElementById("message");
	msg.style.height = "auto";
}, true);

async function loadUsers() {
	try {
		const response = await fetch("/users");
		const data = await response.json();

		const usersList = document.getElementById("users-list");
		usersList.innerHTML = "";

		data.users.sort().forEach((user) => {
			const userDiv = document.createElement("div");
			userDiv.className = "user-item";
			userDiv.textContent = user;
			usersList.appendChild(userDiv);
		});
	} catch (error) {
		console.error("Error loading users:", error);
	}
}

async function getMessageCount() {
	try {
		const response = await fetch("/messages/length");
		const text = await response.json();
		return text.length;
	} catch (error) {
		console.error("Error getting message count:", error);
	}
}

let lastMessageCount = 0;
async function loadMessages(forceUpdate = false, scrollLocation) {
	try {
		const newMessageCount = await getMessageCount();

		const update = newMessageCount != lastMessageCount ||
			lastMessageCount === 0 || forceUpdate;

		let messagesDiv = document.getElementById("messages");
		while (messagesDiv === null) {
			await new Promise((resolve) =>
				setTimeout(resolve, 100)
			);
			messagesDiv = document.getElementById(
				"messages",
			);
		}
		if (messagesDiv.scrollTop != bottom) {
			// show a button to scroll to the bottom
			const scrollToBottomButton = document
				.getElementById(
					"scroll",
				);
			scrollToBottomButton.style.display = "block";
			scrollToBottomButton.onclick = scrollToBottom;
		} else {
			// hide the button
			const scrollToBottomButton = document
				.getElementById(
					"scroll",
				);
			scrollToBottomButton.style.display = "none";
		}
		if (update) {
			const response = await fetch("/messages");
			const text = await response.text();
			const tempDiv = document.createElement("div");
			tempDiv.innerHTML = text;

			const messages = tempDiv.getElementsByTagName("p");
			messagesDiv.innerHTML = "";
			Array.from(messages).forEach((msg) => {
				const messageDiv = document.createElement(
					"div",
				);
				messageDiv.className = "message";
				const [
					messageId,
					username,
					timestamp,
					content,
				] = msg
					.innerHTML.split(
						"<br>",
					);

				const usernameDiv = document.createElement(
					"div",
				);
				usernameDiv.innerHTML = username;
				compareUsername = usernameDiv.textContent;
				let deleteHtml = "";

				const embeddedContent = contentEmbedding(
					content,
				);

				if (
					compareUsername ===
						document.getElementById(
							"current-user",
						).textContent
				) {
					deleteHtml =
						`<button class="delete-button" title="Delete message" onclick="deleteMessage('${messageId}')" style="display: inline;">🗑️</button>`;
				}
				messageDiv.innerHTML = `
					<div class="message-header">
						<div class="username">${username} ${timestamp} ${deleteHtml}</div>
					</div>
					<div class="content">${embeddedContent}</div>`;

				messagesDiv.appendChild(messageDiv);
			});
			if (scrollLocation !== undefined) {
				setScrollLocation(scrollLocation);
			} else {
				scrollToBottom();
			}
			lastMessageCount = newMessageCount;
		}
	} catch (error) {
		console.error("Error loading messages:", error);
	}
}

function contentEmbedding(content) {
	return content.replace(
		/(?![^<]*>)(https?:\/\/[^\s<]+)/g,
		function (url) {
			const videoId = getYouTubeID(
				url,
			);
			if (videoId) {
				return `<div class="video-embed"><iframe 
									width="100%" 
									height="315" 
									src="https://www.youtube.com/embed/${videoId}" 
									frameborder="0" 
									onerror="console.log('Video failed to load:', this.src); this.style.display='none'"
									onload="console.log('Video loaded successfully:', this.src)" 
									allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" 
									allowfullscreen></iframe></div>`;
			} else if (isImageUrl(url)) {
				return `<div class="image-embed"><img 
									src="${url}" 
									alt="Embedded image" 
									loading="lazy" 
									onerror="console.log('Image failed to load:', this.src); this.style.display='none'"
									onload="console.log('Image loaded successfully:', this.src)"></div>`;
			}
			return `<a href="${url}" target="_blank" rel="noopener noreferrer">${url}</a>`;
		},
	);
}

function isImageUrl(url) {
	return url.match(/\.(jpeg|jpg|gif|png|webp|bmp)($|\?)/i) != null;
}

function getYouTubeID(url) {
	// First check if it's a Shorts URL
	if (url.includes("/shorts/")) {
		const shortsMatch = url.match(/\/shorts\/([^/?]+)/);
		return shortsMatch ? shortsMatch[1] : false;
	}

	// Otherwise check regular YouTube URLs
	const regExp =
		/^.*((youtu.be\/)|(v\/)|(\/u\/\w\/)|(embed\/)|(watch\?))\??v?=?([^#&?]*).*/;
	const match = url.match(regExp);
	return (match && match[7].length == 11) ? match[7] : false;
}

function scrollToBottom() {
	const messagesDiv = document.getElementById("messages");
	messagesDiv.scrollTop = messagesDiv.scrollHeight;
	bottom = messagesDiv.scrollTop;
}

async function checkUsername() {
	try {
		const response = await fetch("/username/status");
		const data = await response.json();
		if (!data.hasUsername) {
			document.getElementById("settings-panel").style
				.display = "block";
			const username = document.getElementById("username");
			username.focus();
			username.selectionStart =
				username.selectionEnd =
					username.value.length;
		}
	} catch (error) {
		console.error("Error checking username status:", error);
	}
}

async function updateCurrentUser() {
	try {
		const response = await fetch("/username/status");
		const data = await response.json();
		const userDiv = document.getElementById("current-user");
		if (data.hasUsername) {
			userDiv.textContent = data.username;
		} else {
			userDiv.textContent = "";
		}
	} catch (error) {
		console.error("Error getting username:", error);
	}
}

async function setUsername() {
	const username = document.getElementById("username").value;
	if (!username) {
		showUsernameStatus("Please enter a username", "red");
		return;
	}

	try {
		const response = await fetch("/username", {
			method: "PUT",
			headers: {
				"Content-Type": "application/json",
			},
			body: JSON.stringify({ username: username }),
		});

		const data = await response.json();

		if (response.ok) {
			showUsernameStatus(
				"Username set successfully!",
				"green",
			);
			updateCurrentUser();
			setTimeout(() => {
				document.getElementById("settings-panel").style
					.display = "none";
			}, 750);
			updateMessagesInPlace();
		} else {
			showUsernameStatus(
				data.error || "Failed to set username",
				"red",
			);
		}
	} catch (error) {
		showUsernameStatus("Error connecting to server", "red");
	}
}

let lastMessage = "";
async function sendMessage() {
	const messageInput = document.getElementById("message");
	const message = messageInput.value;
	if (!message) {
		return;
	}

	try {
		lastMessage = message;
		const response = await fetch("/messages", {
			method: "PUT",
			headers: {
				"Content-Type": "application/json",
			},
			body: JSON.stringify({ message: message }),
		});

		const data = await response.json();

		if (response.ok) {
			messageInput.value = "";
			messageInput.style.height = "auto";
			loadMessages(true);
		} else {
			showStatus(
				data.error || "Failed to send message",
				"red",
			);
		}
	} catch (error) {
		showStatus("Error connecting to server", "red");
	}
}

function showStatus(message, color) {
	const status = document.getElementById("status");
	status.textContent = message;
	status.style.color = color;
	setTimeout(() => {
		status.textContent = "";
	}, 3000);
}

function showUsernameStatus(message, color) {
	const status = document.getElementById("username-status");
	status.textContent = message;
	status.style.color = color;
	setTimeout(() => {
		status.textContent = "";
	}, 3000);
}

async function pingCheck() {
	try {
		await fetch("/ping", { method: "POST" });
	} catch (error) {
		console.error("Ping failed:", error);
	}
}

async function timeZoneCheck() {
	try {
		const timeZone =
			Intl.DateTimeFormat().resolvedOptions().timeZone;
		const response = await fetch("/timezone", {
			method: "POST",
			headers: {
				"Content-Type": "application/json",
			},
			body: JSON.stringify({ timezone: timeZone }),
		});
		const data = await response.json();
		if (!response.ok) {
			console.error("Failed to set timezone:", data.error);
		}
	} catch (error) {
		console.error("Error checking timezone:", error);
	}
}

function initializeTheme() {
	const savedTheme = localStorage.getItem("theme");
	if (savedTheme) {
		document.documentElement.setAttribute("data-theme", savedTheme);
	} else {
		// Check system preference
		if (
			window.matchMedia &&
			window.matchMedia("(prefers-color-scheme: light)")
				.matches
		) {
			document.documentElement.setAttribute(
				"data-theme",
				"light",
			);
		} else {
			document.documentElement.setAttribute(
				"data-theme",
				"dark",
			);
		}
	}
}

document.addEventListener("keyup", function (event) {
	const inputPanel = document.getElementById("message");
	if (inputPanel.contains(event.target) && event.key === "ArrowUp") {
		if (inputPanel.value === "") {
			inputPanel.value = lastMessage;
		}
	}
});

let bottom = 0;
async function initialize() {
	usersPanel = document.getElementById("users-panel");
	if (usersPanel) {
		usersPanel.style.display = "none";
	}
	settingsPanel = document.getElementById("settings-panel");
	if (settingsPanel) {
		settingsPanel.style.display = "none";
	}
	initializeTheme();
	await checkUsername();
	await updateCurrentUser();
	await timeZoneCheck();
	setInterval(loadMessages, 1000);
	setInterval(loadUsers, 1000);
	setInterval(pingCheck, 3000);
	await loadMessages(true);
}

initialize();