Add //invite command

d2m/event-dispatcher.js

@@ -18,8 +18,8 @@ const createRoom = sync.require("./actions/create-room")
 const createSpace = sync.require("./actions/create-space")
 /** @type {import("../matrix/api")}) */
 const api = sync.require("../matrix/api")
-/** @type {import("./discord-command-handler")}) */
+/** @type {import("../discord/discord-command-handler")}) */
-const discordCommandHandler = sync.require("./discord-command-handler")
+const discordCommandHandler = sync.require("../discord/discord-command-handler")
 
 let lastReportedEvent = 0
 

discord/discord-command-handler.js

@@ -10,6 +10,8 @@ const {discord, sync, db} = require("../passthrough")
 const api = sync.require("../matrix/api")
 /** @type {import("../matrix/file")} */
 const file = sync.require("../matrix/file")
+/** @type {import("./utils")} */
+const utils = sync.require("./utils")
 
 const PREFIX = "//"
 
@@ -121,9 +123,75 @@ const commands = [{
 	aliases: ["invite"],
 	execute: replyctx(
 		async (message, channel, guild, ctx) => {
-			return discord.snow.channel.createMessage(channel.id, {
+			// Check guild is bridged
+			const spaceID = db.prepare("SELECT space_id FROM guild_space WHERE guild_id = ?").pluck().get(guild.id)
+			const roomID = db.prepare("SELECT room_id FROM channel_room WHERE channel_id = ?").pluck().get(channel.id)
+			if (!spaceID || !roomID) return discord.snow.channel.createMessage(channel.id, {
 				...ctx,
-				content: "This command isn't implemented yet."
+				content: "This server isn't bridged to Matrix, so you can't invite Matrix users."
+			})
+
+			// Check CREATE_INSTANT_INVITE permission
+			assert(message.member)
+			const guildPermissions = utils.getPermissions(message.member.roles, guild.roles)
+			if (!(guildPermissions & BigInt(1))) {
+				return discord.snow.channel.createMessage(channel.id, {
+					...ctx,
+					content: "You don't have permission to invite people to this Discord server."
+				})
+			}
+
+			// Get named MXID
+			const mxid = message.content.match(/@([^:]+):([a-z0-9:-]+\.[a-z0-9.:-]+)/)?.[0]
+			if (!mxid) return discord.snow.channel.createMessage(channel.id, {
+				...ctx,
+				content: "You have to say the Matrix ID of the person you want to invite. Matrix IDs look like this: `@username:example.org`"
+			})
+
+			// Check for existing invite to the space
+			let spaceMember
+			try {
+				spaceMember = await api.getStateEvent(spaceID, "m.room.member", mxid)
+			} catch (e) {}
+			if (spaceMember && spaceMember.membership === "invite") {
+				return discord.snow.channel.createMessage(channel.id, {
+					...ctx,
+					content: `\`${mxid}\` already has an invite, which they haven't accepted yet.`
+				})
+			}
+
+			// Invite Matrix user if not in space
+			if (!spaceMember || spaceMember.membership !== "join") {
+				await api.inviteToRoom(spaceID, mxid)
+				return discord.snow.channel.createMessage(channel.id, {
+					...ctx,
+					content: `You invited \`${mxid}\` to the server.`
+				})
+			}
+
+			// The Matrix user *is* in the space, maybe we want to invite them to this channel?
+			let roomMember
+			try {
+				roomMember = await api.getStateEvent(roomID, "m.room.member", mxid)
+			} catch (e) {}
+			if (!roomMember || (roomMember.membership !== "join" && roomMember.membership !== "invite")) {
+				const sent = await discord.snow.channel.createMessage(channel.id, {
+					...ctx,
+					content: `\`${mxid}\` is already in this server. Would you like to additionally invite them to this specific channel?\nHit ✅ to make it happen.`
+				})
+				return addButton(channel.id, sent.id, "✅", message.author.id).then(async data => {
+					await api.inviteToRoom(roomID, mxid)
+					await discord.snow.channel.createMessage(channel.id, {
+						...ctx,
+						content: `You invited \`${mxid}\` to the channel.`
+					})
+				})
+			}
+
+			// The Matrix user *is* in the space and in the channel.
+			await discord.snow.channel.createMessage(channel.id, {
+				...ctx,
+				content: `\`${mxid}\` is already in this server and this channel.`
 			})
 		}
 	)

discord/utils.js

@@ -0,0 +1,50 @@
+// @ts-check
+
+const DiscordTypes = require("discord-api-types/v10")
+
+/**
+ * @param {string[]} userRoles
+ * @param {DiscordTypes.APIGuild["roles"]} guildRoles
+ * @param {string} [userID]
+ * @param {DiscordTypes.APIGuildChannel["permission_overwrites"]} [channelOverwrites]
+ */
+function getPermissions(userRoles, guildRoles, userID, channelOverwrites) {
+	let allowed = BigInt(0)
+	let everyoneID
+	// Guild allows
+	for (const role of guildRoles) {
+		if (role.name === "@everyone") {
+			allowed |= BigInt(role.permissions)
+			everyoneID = role.id
+		}
+		if (userRoles.includes(role.id)) {
+			allowed |= BigInt(role.permissions)
+		}
+	}
+
+	if (channelOverwrites) {
+		/** @type {((overwrite: Required<DiscordTypes.APIGuildChannel>["permission_overwrites"][0]) => any)[]} */
+		const actions = [
+			// Channel @everyone deny
+			overwrite => overwrite.id === everyoneID && (allowed &= ~BigInt(overwrite.deny)),
+			// Channel @everyone allow
+			overwrite => overwrite.id === everyoneID && (allowed |= BigInt(overwrite.allow)),
+			// Role deny
+			overwrite => userRoles.includes(overwrite.id) && (allowed &= ~BigInt(overwrite.deny)),
+			// Role allow
+			overwrite => userRoles.includes(overwrite.id) && (allowed |= ~BigInt(overwrite.allow)),
+			// User deny
+			overwrite => overwrite.id === userID && (allowed &= ~BigInt(overwrite.deny)),
+			// User allow
+			overwrite => overwrite.id === userID && (allowed |= BigInt(overwrite.allow))
+		]
+		for (let i = 0; i < actions.length; i++) {
+			for (const overwrite of channelOverwrites) {
+				actions[i](overwrite)
+			}
+		}
+	}
+	return allowed
+}
+
+module.exports.getPermissions = getPermissions