const { mClient } = require("..");

async function getMember(client, userId) {
	const guild = client.guilds.cache.get(process.env.D_GuildID);

	if (!guild) {
		return null;
	}

	// Cache first
	let member = guild.members.cache.get(userId);

	// Fallback to API fetch
	if (!member) {
		member = await guild.members.fetch(userId).catch(() => null);
	}

	return member;
}

module.exports = {
	name: 'timerComplete',

	async execute(timer, client) {
		const db = mClient.db('neo-db');

		const wgeColl = db.collection('timer_wge');
		const participateColl = db.collection('items_wge');
		const channelColl = db.collection('config_channels');

		const guild = client.guilds.cache.get(process.env.D_GuildID);

		if (!guild) {
			console.error('timerComplete: Guild not found.');
			return;
		}

		// Notify previous assignee via DM
		const previousMember = await getMember(client, timer.assignedUser);

		if (previousMember) {
			await previousMember.send(
				`❌ Timer ran out: **${timer.topic}** ...Re-assigning randomly...`
			).catch(() => {});
		}

		// Find the configured WGE channel
		const wgeChannelConfig = await channelColl.findOne({
			purpose: 'wge',
			guildID: process.env.D_GuildID
		});

		if (!wgeChannelConfig) {
			console.error('timerComplete: WGE channel configuration not found.');
			return;
		}

		const channel = client.channels.cache.get(wgeChannelConfig.channelID);

		if (!channel) {
			console.error('timerComplete: WGE channel not found.');
			return;
		}

		// Pick a random participant, excluding the previous assignee
		const randomParticipant = await participateColl.aggregate([
			{
				$match: {
					status: true,
					userID: { $ne: timer.assignedUser }
				}
			},
			{
				$sample: {
					size: 1
				}
			}
		]).toArray();

		// Nobody else is available
		if (!randomParticipant.length) {
			await channel.send({
				content:
					`The timer for <@${timer.assignedUser}> has run out, ` +
					`but there are currently no other participating users available for reassignment.`
			});

			return;
		}

		const newMember = await guild.members
			.fetch(randomParticipant[0].userID)
			.catch(() => null);

		if (!newMember) {
			console.error(
				`timerComplete: Could not fetch selected user ${randomParticipant[0].userID}.`
			);
			return;
		}

		const newAssignedUser = newMember.user;

		const wgeDefaultAssignedTime =
			7 * 24 * 60 * 60 * 1000; // 7 days

		// Remove the expired timer specifically
		await wgeColl.deleteOne({
			_id: timer._id
		});

		// Create the new timer
		await wgeColl.insertOne({
			assignedUser: newAssignedUser.id,
			assigningUser: timer.assigningUser,

			startedAt: Date.now(),
			timeRemaining: wgeDefaultAssignedTime,

			state: 'running',

			notifications: {
				half: false,
				day24: false,
				complete: false
			},

			topic: timer.topic,
			debug: false,

			createdAt: new Date()
		});

		// Announce reassignment
		await channel.send({
			content:
				`The timer for <@${timer.assignedUser}> has run out! Assigning randomly...\n` +
				`<@${newAssignedUser.id}> is the next expert! Their topic is still **${timer.topic}**`
		});
	}
};