fix(channels): close ticket when the channel is deleted

- change close function on manager so tickets without channel can be closed
- create an event listener to close tickets when someone deletes a channel
Note: The ticket will be closed when someone deletes the channel,
but it is supposed to be a fallback. Pinned messages will
not be stored.

Fixes #276

src/listeners/channelDelete.js

@@ -0,0 +1,23 @@
+const EventListener = require('../modules/listeners/listener');
+
+module.exports = class ChannelDeleteEventListener extends EventListener {
+	constructor(client) {
+		super(client, { event: 'channelDelete' });
+	}
+
+	async execute(channel) {
+		if (!channel.guild || channel.type !== 'GUILD_TEXT') return;
+
+		// resolve ticket by id
+		const t_row = await this.client.tickets.resolve(channel.id, channel.guild.id);
+		if (!t_row) return;
+
+		// fetch user from audit logs
+		const logEntry = (await channel.guild.fetchAuditLogs({ type: 'CHANNEL_DELETE' })).entries.find(entry =>
+			entry.target.id === channel.id
+		);
+		if (logEntry.executor.id === this.client.user.id) return;
+
+		await this.client.tickets.close(t_row.id, logEntry?.executor?.id || null, channel.guild.id, 'Channel was deleted');
+	}
+};

src/modules/tickets/manager.js

@@ -236,15 +236,20 @@ module.exports = class TicketManager extends EventEmitter {
 		const guild = this.client.guilds.cache.get(t_row.guild);
 		const settings = await this.client.utils.getSettings(guild.id);
 		const i18n = this.client.i18n.getLocale(settings.locale);
-		const channel = await this.client.channels.fetch(t_row.id);
+		const channel = await this.client.channels.cache.find(channel =>
+			channel.id === t_row.id
+		) ? await this.client.channels.fetch(t_row.id) : null;
 
 		const close = async () => {
-			const pinned = await channel.messages.fetchPinned();
+			let pinned;
+			if (channel) {
+				pinned = await channel.messages.fetchPinned();
+			}
 			await t_row.update({
 				closed_by: closer_id || null,
 				closed_reason: reason ? this.client.cryptr.encrypt(reason) : null,
 				open: false,
-				pinned_messages: [...pinned.keys()]
+				pinned_messages: pinned ? [...pinned.keys()] : []
 			});
 
 			if (closer_id) {
@@ -252,6 +257,7 @@ module.exports = class TicketManager extends EventEmitter {
 
 				await this.archives.updateMember(ticket_id, closer);
 
+				if (channel) {
 					const description = reason
 						? i18n('ticket.closed_by_member_with_reason.description', closer.user.toString(), reason)
 						: i18n('ticket.closed_by_member.description', closer.user.toString());
@@ -269,9 +275,11 @@ module.exports = class TicketManager extends EventEmitter {
 					setTimeout(async () => {
 						await channel.delete(`Ticket channel closed by ${closer.user.tag}${reason ? `: "${reason}"` : ''}`);
 					}, 5000);
+				}
 
 				this.client.log.info(`${closer.user.tag} closed a ticket (${ticket_id})${reason ? `: "${reason}"` : ''}`);
 			} else {
+				if (channel) {
 					const description = reason
 						? i18n('ticket.closed_with_reason.description')
 						: i18n('ticket.closed.description');
@@ -288,6 +296,7 @@ module.exports = class TicketManager extends EventEmitter {
 					setTimeout(async () => {
 						await channel.delete(`Ticket channel closed${reason ? `: "${reason}"` : ''}`);
 					}, 5000);
+				}
 
 				this.client.log.info(`A ticket was closed (${ticket_id})${reason ? `: "${reason}"` : ''}`);
 			}
@@ -409,6 +418,8 @@ module.exports = class TicketManager extends EventEmitter {
 					this.client.log.debug(error);
 					await close();
 				});
+		} else {
+			await close();
 		}
 
 		this.emit('close', ticket_id);
@@ -423,9 +434,7 @@ module.exports = class TicketManager extends EventEmitter {
 	async resolve(ticket_id, guild_id) {
 		let t_row;
 
-		if (this.client.channels.resolve(ticket_id)) {
+		if (!(t_row = await this.client.db.models.Ticket.findOne({ where: { id: ticket_id } }))) {
-			t_row = await this.client.db.models.Ticket.findOne({ where: { id: ticket_id } });
-		} else {
 			t_row = await this.client.db.models.Ticket.findOne({
 				where: {
 					guild: guild_id,