LapisDeploy/matrix.go

// package main is the main package for the LapisDeploy program
package main

import (
	"context"
	"fmt"
	"log"
	"strings"
	"sync"
	"time"

	"maunium.net/go/mautrix"
	"maunium.net/go/mautrix/event"
	"maunium.net/go/mautrix/format"
	"maunium.net/go/mautrix/id"
)

// MatrixMessage stores information about a matrix message.
type MatrixMessage struct {
	text  string
	level int
}

// MatrixCommandCallback is a function that gets called when the bot is issued a command over Matrix
type MatrixCommandCallback func(ctx context.Context, evt *event.Event, args []string) string

// MatrixCommand stores information about a matrix chat command
type MatrixCommand struct {
	cmd         string
	callback    MatrixCommandCallback
	description string
}

// Output queue.
var MatrixOut struct {
	queue []MatrixMessage
	mux   sync.Mutex
}

// sendMessage sends a message through Matrix.
func sendMessage(msg MatrixMessage) {
	log.Print(msg.text)
	MatrixOut.mux.Lock()
	MatrixOut.queue = append(MatrixOut.queue, msg)
	MatrixOut.mux.Unlock()
}

// sendError sends an error through Matrix.
func sendError(err error) {
	sendMessage(MatrixMessage{
		text: fmt.Sprintf("%s %s", Circles["red"], err),
	})
}

// sendInfo sends a bit of info text through Matrix.
func sendInfo(text string) {
	sendMessage(MatrixMessage{
		text: fmt.Sprintf("%s %s", Circles["white"], text),
	})
}

// initMatrix starts a Matrix bot.
func initMatrix() {
	client, err := mautrix.NewClient(configuration.matrix.homeserver, "", "")
	if err != nil {
		log.Fatal(err)
	}
	resp, err := client.Login(context.Background(), &mautrix.ReqLogin{
		Type:             "m.login.password",
		Identifier:       mautrix.UserIdentifier{Type: mautrix.IdentifierTypeUser, User: configuration.matrix.username},
		Password:         configuration.matrix.password,
		StoreCredentials: true,
	})
	if err != nil {
		log.Panic(err)
	}
	log.Printf("[Matrix] Logged in as %s", resp.UserID)

	syncer := client.Syncer.(*mautrix.DefaultSyncer)
	client.Syncer.(mautrix.ExtensibleSyncer).OnSync(client.DontProcessOldEvents)
	syncer.OnEventType(event.StateMember, func(ctx context.Context, evt *event.Event) {
		if evt.GetStateKey() == client.UserID.String() && evt.Content.AsMember().Membership == event.MembershipInvite {
			if evt.RoomID.String() == configuration.matrix.room_id {
				_, err := client.JoinRoomByID(ctx, evt.RoomID)
				if err == nil {
					log.Printf("[Matrix] Joined room '%s' (Invited by '%s')", evt.RoomID.String(), evt.Sender.String())
				} else {
					log.Printf("[Matrix] Failed to join room '%s' after invite (Invited by '%s')", evt.RoomID.String(), evt.Sender.String())
				}
			} else {
				log.Printf("[Matrix] Rejected invite to room '%s' (Invited by '%s')", evt.RoomID.String(), evt.Sender.String())
			}
		}
	})
	syncer.OnEventType(event.EventMessage, func(ctx context.Context, evt *event.Event) {
		if evt.RoomID.String() == configuration.matrix.room_id {
			prefixes := []string{"!", configuration.matrix.username + " "}
			for _, prefix := range prefixes {
				if strings.HasPrefix(evt.Content.AsMessage().Body, prefix) {
					msg := evt.Content.AsMessage().Body
					cmd := strings.TrimPrefix(strings.Split(msg, " ")[0], prefix)
					found_command := false
					for _, command := range Chatcommands {
						if command.cmd == cmd {
							found_command = true
							out := command.callback(ctx, evt, strings.Split(strings.TrimPrefix(msg, prefix+cmd), " "))
							content := format.RenderMarkdown(out, true, false)
							content.SetReply(evt)
							client.SendMessageEvent(ctx, evt.RoomID, event.EventMessage, content)
						}
					}
					if !found_command {
						client.SendText(ctx, evt.RoomID, Circles["red"]+"Command not found")
					}
					break
				}
			}
		}
	})

	registerChatCommands() // Register all the chat commands defined inside matrix_commands.go

	go func() {
		for range time.Tick(time.Second * 2) {
			MatrixOut.mux.Lock()
			if len(MatrixOut.queue) > 0 {
				text := ""
				for i, msg := range MatrixOut.queue {
					text += msg.text
					if i != len(MatrixOut.queue) {
						text += "\n"
					}
				}
				MatrixOut.queue = []MatrixMessage{}
				_, err := client.SendMessageEvent(context.Background(),
					id.RoomID(configuration.matrix.room_id),
					event.EventMessage,
					format.RenderMarkdown(text, true, false),
				)
				if err != nil {
					log.Printf("[Matrix] ERROR : %s", err)
					continue
				}
			}
			MatrixOut.mux.Unlock()
		}
	}()

	go func() {
		log.Print("[Matrix] Running!")
		err = client.Sync()
		if err != nil {
			log.Fatal(err)
		}
	}()
}