3 files changed, 493 insertions, 0 deletions
diff --git a/bridge/whatsapp/handlers.go b/bridge/whatsapp/handlers.go
new file mode 100644
index 00000000..456f2009
--- /dev/null
+++ b/bridge/whatsapp/handlers.go
@@ -0,0 +1,104 @@
+package bwhatsapp
+
+import (
+	"strings"
+	"time"
+
+	"github.com/42wim/matterbridge/bridge/config"
+
+	"github.com/Rhymen/go-whatsapp"
+
+	whatsappExt "maunium.net/go/mautrix-whatsapp/whatsapp-ext"
+)
+
+/*
+Implement handling messages coming from WhatsApp
+Check:
+- https://github.com/Rhymen/go-whatsapp#add-message-handlers
+- https://github.com/Rhymen/go-whatsapp/blob/master/handler.go
+- https://github.com/tulir/mautrix-whatsapp/tree/master/whatsapp-ext for more advanced command handling
+*/
+
+// HandleError received from WhatsApp
+func (b *Bwhatsapp) HandleError(err error) {
+	b.Log.Errorf("%v", err) // TODO implement proper handling? at least respond to different error types
+}
+
+// HandleTextMessage sent from WhatsApp, relay it to the brige
+func (b *Bwhatsapp) HandleTextMessage(message whatsapp.TextMessage) {
+	if message.Info.FromMe { // || !strings.Contains(strings.ToLower(message.Text), "@echo") {
+		return
+	}
+	// whatsapp sends last messages to show context , cut them
+	if message.Info.Timestamp < b.startedAt {
+		return
+	}
+
+	messageTime := time.Unix(int64(message.Info.Timestamp), 0) // TODO check how behaves between timezones
+	groupJid := message.Info.RemoteJid
+
+	senderJid := message.Info.SenderJid
+	if len(senderJid) == 0 {
+		// TODO workaround till https://github.com/Rhymen/go-whatsapp/issues/86 resolved
+		senderJid = *message.Info.Source.Participant
+	}
+
+	// translate sender's Jid to the nicest username we can get
+	senderName := b.getSenderName(senderJid)
+	if senderName == "" {
+		senderName = "Someone" // don't expose telephone number
+	}
+
+	extText := message.Info.Source.Message.ExtendedTextMessage
+	if extText != nil && extText.ContextInfo != nil && extText.ContextInfo.MentionedJid != nil {
+		// handle user mentions
+		for _, mentionedJid := range extText.ContextInfo.MentionedJid {
+			numberAndSuffix := strings.SplitN(mentionedJid, "@", 2)
+
+			// mentions comes as telephone numbers and we don't want to expose it to other bridges
+			// replace it with something more meaninful to others
+			mention := b.getSenderNotify(numberAndSuffix[0] + whatsappExt.NewUserSuffix)
+			if mention == "" {
+				mention = "someone"
+			}
+			message.Text = strings.Replace(message.Text, "@"+numberAndSuffix[0], "@"+mention, 1)
+		}
+	}
+
+	b.Log.Debugf("<= Sending message from %s on %s to gateway", senderJid, b.Account)
+	rmsg := config.Message{
+		UserID:    senderJid,
+		Username:  senderName,
+		Text:      message.Text,
+		Timestamp: messageTime,
+		Channel:   groupJid,
+		Account:   b.Account,
+		Protocol:  b.Protocol,
+		Extra:     make(map[string][]interface{}),
+		//		ParentID: TODO, // TODO handle thread replies  // map from Info.QuotedMessageID string
+		//	Event     string    `json:"event"`
+		//	Gateway   string  // will be added during message processing
+		ID: message.Info.Id}
+
+	if avatarURL, exists := b.userAvatars[senderJid]; exists {
+		rmsg.Avatar = avatarURL
+	}
+
+	b.Log.Debugf("<= Message is %#v", rmsg)
+	b.Remote <- rmsg
+}
+
+//
+//func (b *Bwhatsapp) HandleImageMessage(message whatsapp.ImageMessage) {
+//	fmt.Println(message) // TODO implement
+//}
+//
+//func (b *Bwhatsapp) HandleVideoMessage(message whatsapp.VideoMessage) {
+//	fmt.Println(message) // TODO implement
+//}
+//
+//func (b *Bwhatsapp) HandleJsonMessage(message string) {
+//	fmt.Println(message) // TODO implement
+//}
+// TODO HandleRawMessage
+// TODO HandleAudioMessage
diff --git a/bridge/whatsapp/helpers.go b/bridge/whatsapp/helpers.go
new file mode 100644
index 00000000..5268ba3e
--- /dev/null
+++ b/bridge/whatsapp/helpers.go
@@ -0,0 +1,84 @@
+package bwhatsapp
+
+import (
+	"encoding/gob"
+	"errors"
+	"os"
+
+	qrcodeTerminal "github.com/Baozisoftware/qrcode-terminal-go"
+	"github.com/Rhymen/go-whatsapp"
+)
+
+func qrFromTerminal(invert bool) chan string {
+	qr := make(chan string)
+	go func() {
+		terminal := qrcodeTerminal.New()
+		if invert {
+			terminal = qrcodeTerminal.New2(qrcodeTerminal.ConsoleColors.BrightWhite, qrcodeTerminal.ConsoleColors.BrightBlack, qrcodeTerminal.QRCodeRecoveryLevels.Medium)
+		}
+
+		terminal.Get(<-qr).Print()
+	}()
+
+	return qr
+}
+
+func (b *Bwhatsapp) readSession() (whatsapp.Session, error) {
+	session := whatsapp.Session{}
+	sessionFile := b.Config.GetString(sessionFile)
+
+	if sessionFile == "" {
+		return session, errors.New("if you won't set SessionFile then you will need to scan QR code on every restart")
+	}
+
+	file, err := os.Open(sessionFile)
+	if err != nil {
+		return session, err
+	}
+	defer file.Close()
+	decoder := gob.NewDecoder(file)
+	err = decoder.Decode(&session)
+	if err != nil {
+		return session, err
+	}
+	return session, nil
+}
+
+func (b *Bwhatsapp) writeSession(session whatsapp.Session) error {
+	sessionFile := b.Config.GetString(sessionFile)
+
+	if sessionFile == "" {
+		// we already sent a warning while starting the bridge, so let's be quiet here
+		return nil
+	}
+
+	file, err := os.Create(sessionFile)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	encoder := gob.NewEncoder(file)
+	err = encoder.Encode(session)
+
+	return err
+}
+
+func (b *Bwhatsapp) getSenderName(senderJid string) string {
+	if sender, exists := b.users[senderJid]; exists {
+		if sender.Name != "" {
+			return sender.Name
+		}
+		// if user is not in phone contacts
+		// it is the most obvious scenario unless you sync your phone contacts with some remote updated source
+		// users can change it in their WhatsApp settings -> profile -> click on Avatar
+		return sender.Notify
+	}
+	return ""
+}
+
+func (b *Bwhatsapp) getSenderNotify(senderJid string) string {
+	if sender, exists := b.users[senderJid]; exists {
+		return sender.Notify
+	}
+	return ""
+}
diff --git a/bridge/whatsapp/whatsapp.go b/bridge/whatsapp/whatsapp.go
new file mode 100644
index 00000000..e17339d8
--- /dev/null
+++ b/bridge/whatsapp/whatsapp.go
@@ -0,0 +1,305 @@
+package bwhatsapp
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/42wim/matterbridge/bridge"
+	"github.com/42wim/matterbridge/bridge/config"
+
+	"github.com/Rhymen/go-whatsapp"
+
+	whatsappExt "maunium.net/go/mautrix-whatsapp/whatsapp-ext"
+)
+
+const (
+	// Account config parameters
+	cfgNumber         = "Number"
+	qrOnWhiteTerminal = "QrOnWhiteTerminal"
+	sessionFile       = "SessionFile"
+)
+
+// Bwhatsapp Bridge structure keeping all the information needed for relying
+type Bwhatsapp struct {
+	*bridge.Config
+
+	// https://github.com/Rhymen/go-whatsapp/blob/c31092027237441cffba1b9cb148eadf7c83c3d2/session.go#L18-L21
+	session *whatsapp.Session
+	conn    *whatsapp.Conn
+	// https://github.com/tulir/mautrix-whatsapp/blob/master/whatsapp-ext/whatsapp.go
+	connExt   *whatsappExt.ExtendedConn
+	startedAt uint64
+
+	users       map[string]whatsapp.Contact
+	userAvatars map[string]string
+}
+
+// New Create a new WhatsApp bridge. This will be called for each [whatsapp.<server>] entry you have in the config file
+func New(cfg *bridge.Config) bridge.Bridger {
+	number := cfg.GetString(cfgNumber)
+	if number == "" {
+		cfg.Log.Fatalf("Missing configuration for WhatsApp bridge: Number")
+	}
+
+	b := &Bwhatsapp{
+		Config: cfg,
+
+		users:       make(map[string]whatsapp.Contact),
+		userAvatars: make(map[string]string),
+	}
+	return b
+}
+
+// Connect to WhatsApp. Required implementation of the Bridger interface
+// https://github.com/42wim/matterbridge/blob/2cfd880cdb0df29771bf8f31df8d990ab897889d/bridge/bridge.go#L11-L16
+func (b *Bwhatsapp) Connect() error {
+	b.RLock() // TODO do we need locking for Whatsapp?
+	defer b.RUnlock()
+
+	number := b.GetString(cfgNumber)
+	if number == "" {
+		return errors.New("WhatsApp's telephone Number need to be configured")
+	}
+
+	// https://github.com/Rhymen/go-whatsapp#creating-a-connection
+	b.Log.Debugln("Connecting to WhatsApp..")
+	conn, err := whatsapp.NewConn(20 * time.Second)
+	if err != nil {
+		return errors.New("failed to connect to WhatsApp: " + err.Error())
+	}
+
+	b.conn = conn
+	b.connExt = whatsappExt.ExtendConn(b.conn)
+	// TODO do we want to use it? b.connExt.SetClientName("Matterbridge WhatsApp bridge", "mb-wa")
+
+	b.conn.AddHandler(b)
+	b.Log.Debugln("WhatsApp connection successful")
+
+	// load existing session in order to keep it between restarts
+	if b.session == nil {
+		var session whatsapp.Session
+		session, err = b.readSession()
+
+		if err == nil {
+			b.Log.Debugln("Restoring WhatsApp session..")
+
+			// https://github.com/Rhymen/go-whatsapp#restore
+			session, err = b.conn.RestoreSession(session)
+			if err != nil {
+				// TODO return or continue to normal login?
+				// restore session connection timed out (I couldn't get over it without logging in again)
+				return errors.New("failed to restore session: " + err.Error())
+			}
+
+			b.session = &session
+			b.Log.Debugln("Session restored successfully!")
+		} else {
+			b.Log.Warn(err.Error())
+		}
+	}
+
+	// login to a new session
+	if b.session == nil {
+		err = b.Login()
+		if err != nil {
+			return err
+		}
+	}
+	b.startedAt = uint64(time.Now().Unix())
+
+	_, err = b.conn.Contacts()
+	if err != nil {
+		return fmt.Errorf("error on update of contacts: %v", err)
+	}
+
+	// map all the users
+	for id, contact := range b.conn.Store.Contacts {
+		if !isGroupJid(id) && id != "status@broadcast" {
+			// it is user
+			b.users[id] = contact
+		}
+	}
+
+	// get user avatar asynchronously
+	go func() {
+		b.Log.Debug("Getting user avatars..")
+
+		for jid := range b.users {
+			info, err := b.connExt.GetProfilePicThumb(jid)
+			if err != nil {
+				b.Log.Warnf("Could not get profile photo of %s: %v", jid, err)
+
+			} else {
+				// TODO any race conditions here?
+				b.userAvatars[jid] = info.URL
+			}
+		}
+		b.Log.Debug("Finished getting avatars..")
+	}()
+
+	return nil
+}
+
+// Login to WhatsApp creating a new session. This will require to scan a QR code on your mobile device
+func (b *Bwhatsapp) Login() error {
+	b.Log.Debugln("Logging in..")
+
+	invert := b.GetBool(qrOnWhiteTerminal) // false is the default
+	qrChan := qrFromTerminal(invert)
+
+	session, err := b.conn.Login(qrChan)
+	if err != nil {
+		b.Log.Warnln("Failed to log in:", err)
+		return err
+	}
+	b.session = &session
+
+	b.Log.Infof("Logged into session: %#v", session)
+	b.Log.Infof("Connection: %#v", b.conn)
+
+	err = b.writeSession(session)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error saving session: %v\n", err)
+	}
+
+	// TODO change connection strings to configured ones longClientName:"github.com/rhymen/go-whatsapp", shortClientName:"go-whatsapp"}" prefix=whatsapp
+	// TODO get also a nice logo
+
+	// TODO notification about unplugged and dead battery
+	// conn.Info: Wid, Pushname, Connected, Battery, Plugged
+
+	return nil
+}
+
+// Disconnect is called while reconnecting to the bridge
+// TODO 42wim Documentation would be helpful on when reconnects happen and what should be done in this function
+// Required implementation of the Bridger interface
+// https://github.com/42wim/matterbridge/blob/2cfd880cdb0df29771bf8f31df8d990ab897889d/bridge/bridge.go#L11-L16
+func (b *Bwhatsapp) Disconnect() error {
+	// We could Logout, but that would close the session completely and would require a new QR code scan
+	// https://github.com/Rhymen/go-whatsapp/blob/c31092027237441cffba1b9cb148eadf7c83c3d2/session.go#L377-L381
+	return nil
+}
+
+func isGroupJid(identifier string) bool {
+	return strings.HasSuffix(identifier, "@g.us") || strings.HasSuffix(identifier, "@temp")
+}
+
+// JoinChannel Join a WhatsApp group specified in gateway config as channel='number-id@g.us' or channel='Channel name'
+// Required implementation of the Bridger interface
+// https://github.com/42wim/matterbridge/blob/2cfd880cdb0df29771bf8f31df8d990ab897889d/bridge/bridge.go#L11-L16
+func (b *Bwhatsapp) JoinChannel(channel config.ChannelInfo) error {
+	byJid := isGroupJid(channel.Name)
+
+	// verify if we are member of the given group
+	if byJid {
+		// channel.Name specifies static group jID, not the name
+		if _, exists := b.conn.Store.Contacts[channel.Name]; !exists {
+			return fmt.Errorf("account doesn't belong to group with jid %s", channel.Name)
+		}
+	} else {
+		// channel.Name specifies group name that might change, warn about it
+		var jids []string
+		for id, contact := range b.conn.Store.Contacts {
+			if isGroupJid(id) && contact.Name == channel.Name {
+				jids = append(jids, id)
+			}
+		}
+
+		switch len(jids) {
+		case 0:
+			// didn't match any group - print out possibilites
+			// TODO sort
+			// copy b;
+			//sort.Slice(people, func(i, j int) bool {
+			//	return people[i].Age > people[j].Age
+			//})
+			for id, contact := range b.conn.Store.Contacts {
+				if isGroupJid(id) {
+					b.Log.Infof("%s %s", contact.Jid, contact.Name)
+				}
+			}
+			return fmt.Errorf("please specify group's JID from the list above instead of the name '%s'", channel.Name)
+
+		case 1:
+			return fmt.Errorf("group name might change. Please configure gateway with channel=\"%v\" instead of channel=\"%v\"", jids[0], channel.Name)
+
+		default:
+			return fmt.Errorf("there is more than one group with name '%s'. Please specify one of JIDs as channel name: %v", channel.Name, jids)
+		}
+	}
+
+	return nil
+}
+
+// Send a message from the bridge to WhatsApp
+// Required implementation of the Bridger interface
+// https://github.com/42wim/matterbridge/blob/2cfd880cdb0df29771bf8f31df8d990ab897889d/bridge/bridge.go#L11-L16
+func (b *Bwhatsapp) Send(msg config.Message) (string, error) {
+	b.Log.Debugf("=> Receiving %#v", msg)
+
+	// Delete message
+	if msg.Event == config.EventMsgDelete {
+		if msg.ID == "" {
+			// No message ID in case action is executed on a message sent before the bridge was started
+			// and then the bridge cache doesn't have this message ID mapped
+
+			// TODO 42wim Doesn't the app get clogged with a ton of IDs after some time of running?
+			// WhatsApp allows to set any ID so in that case we could use external IDs and don't do mapping
+			// but external IDs are not set
+			return "", nil
+		}
+		// TODO delete message on WhatsApp https://github.com/Rhymen/go-whatsapp/issues/100
+		return "", nil
+	}
+
+	// Edit message
+	if msg.ID != "" {
+		b.Log.Debugf("updating message with id %s", msg.ID)
+
+		msg.Text += " (edited)"
+		// TODO handle edit as a message reply with updated text
+	}
+
+	//// TODO Handle Upload a file
+	//if msg.Extra != nil {
+	//	for _, rmsg := range helper.HandleExtra(&msg, b.General) {
+	//		b.c.SendMessage(roomID, rmsg.Username+rmsg.Text)
+	//	}
+	//	if len(msg.Extra["file"]) > 0 {
+	//		return b.handleUploadFile(&msg, roomID)
+	//	}
+	//}
+
+	// Post text message
+	text := whatsapp.TextMessage{
+		Info: whatsapp.MessageInfo{
+			RemoteJid: msg.Channel, // which equals to group id
+		},
+		Text: msg.Username + msg.Text,
+	}
+
+	b.Log.Debugf("=> Sending %#v", msg)
+
+	// create message ID
+	// TODO follow and act if https://github.com/Rhymen/go-whatsapp/issues/101 implemented
+	bytes := make([]byte, 10)
+	if _, err := rand.Read(bytes); err != nil {
+		b.Log.Warn(err.Error())
+	}
+	text.Info.Id = strings.ToUpper(hex.EncodeToString(bytes))
+
+	err := b.conn.Send(text)
+
+	return text.Info.Id, err
+}
+
+// TODO do we want that? to allow login with QR code from a bridged channel? https://github.com/tulir/mautrix-whatsapp/blob/513eb18e2d59bada0dd515ee1abaaf38a3bfe3d5/commands.go#L76
+//func (b *Bwhatsapp) Command(cmd string) string {
+//	return ""
+//}