Refactor mattermost bridge (#622)

* Split up in different files
* Decrease complexity
* Fix linting issues

1 files changed, 194 insertions, 0 deletions

diff --git a/bridge/mattermost/handlers.go b/bridge/mattermost/handlers.go
new file mode 100644
index 00000000..d75e8d40
--- /dev/null
+++ b/bridge/mattermost/handlers.go
@@ -0,0 +1,194 @@
+package bmattermost
+
+import (
+	"github.com/42wim/matterbridge/bridge/config"
+	"github.com/42wim/matterbridge/bridge/helper"
+	"github.com/42wim/matterbridge/matterclient"
+	"github.com/mattermost/mattermost-server/model"
+)
+
+// handleDownloadAvatar downloads the avatar of userid from channel
+// sends a EVENT_AVATAR_DOWNLOAD message to the gateway if successful.
+// logs an error message if it fails
+func (b *Bmattermost) handleDownloadAvatar(userid string, channel string) {
+	rmsg := config.Message{
+		Username: "system",
+		Text:     "avatar",
+		Channel:  channel,
+		Account:  b.Account,
+		UserID:   userid,
+		Event:    config.EventAvatarDownload,
+		Extra:    make(map[string][]interface{}),
+	}
+	if _, ok := b.avatarMap[userid]; !ok {
+		data, resp := b.mc.Client.GetProfileImage(userid, "")
+		if resp.Error != nil {
+			b.Log.Errorf("ProfileImage download failed for %#v %s", userid, resp.Error)
+			return
+		}
+		err := helper.HandleDownloadSize(b.Log, &rmsg, userid+".png", int64(len(data)), b.General)
+		if err != nil {
+			b.Log.Error(err)
+			return
+		}
+		helper.HandleDownloadData(b.Log, &rmsg, userid+".png", rmsg.Text, "", &data, b.General)
+		b.Remote <- rmsg
+	}
+}
+
+// handleDownloadFile handles file download
+func (b *Bmattermost) handleDownloadFile(rmsg *config.Message, id string) error {
+	url, _ := b.mc.Client.GetFileLink(id)
+	finfo, resp := b.mc.Client.GetFileInfo(id)
+	if resp.Error != nil {
+		return resp.Error
+	}
+	err := helper.HandleDownloadSize(b.Log, rmsg, finfo.Name, finfo.Size, b.General)
+	if err != nil {
+		return err
+	}
+	data, resp := b.mc.Client.DownloadFile(id, true)
+	if resp.Error != nil {
+		return resp.Error
+	}
+	helper.HandleDownloadData(b.Log, rmsg, finfo.Name, rmsg.Text, url, &data, b.General)
+	return nil
+}
+
+func (b *Bmattermost) handleMatter() {
+	messages := make(chan *config.Message)
+	if b.GetString("WebhookBindAddress") != "" {
+		b.Log.Debugf("Choosing webhooks based receiving")
+		go b.handleMatterHook(messages)
+	} else {
+		if b.GetString("Token") != "" {
+			b.Log.Debugf("Choosing token based receiving")
+		} else {
+			b.Log.Debugf("Choosing login/password based receiving")
+		}
+		go b.handleMatterClient(messages)
+	}
+	var ok bool
+	for message := range messages {
+		message.Avatar = helper.GetAvatar(b.avatarMap, message.UserID, b.General)
+		message.Account = b.Account
+		message.Text, ok = b.replaceAction(message.Text)
+		if ok {
+			message.Event = config.EventUserAction
+		}
+		b.Log.Debugf("<= Sending message from %s on %s to gateway", message.Username, b.Account)
+		b.Log.Debugf("<= Message is %#v", message)
+		b.Remote <- *message
+	}
+}
+
+func (b *Bmattermost) handleMatterClient(messages chan *config.Message) {
+	for message := range b.mc.MessageChan {
+		b.Log.Debugf("%#v", message.Raw.Data)
+
+		if b.skipMessage(message) {
+			b.Log.Debugf("Skipped message: %#v", message)
+			continue
+		}
+
+		// only download avatars if we have a place to upload them (configured mediaserver)
+		if b.General.MediaServerUpload != "" || b.General.MediaDownloadPath != "" {
+			b.handleDownloadAvatar(message.UserID, message.Channel)
+		}
+
+		b.Log.Debugf("== Receiving event %#v", message)
+
+		rmsg := &config.Message{
+			Username: message.Username,
+			UserID:   message.UserID,
+			Channel:  message.Channel,
+			Text:     message.Text,
+			ID:       message.Post.Id,
+			Extra:    make(map[string][]interface{}),
+		}
+
+		// handle mattermost post properties (override username and attachments)
+		b.handleProps(rmsg, message)
+
+		// create a text for bridges that don't support native editing
+		if message.Raw.Event == model.WEBSOCKET_EVENT_POST_EDITED && !b.GetBool("EditDisable") {
+			rmsg.Text = message.Text + b.GetString("EditSuffix")
+		}
+
+		if message.Raw.Event == model.WEBSOCKET_EVENT_POST_DELETED {
+			rmsg.Event = config.EventMsgDelete
+		}
+
+		for _, id := range message.Post.FileIds {
+			err := b.handleDownloadFile(rmsg, id)
+			if err != nil {
+				b.Log.Errorf("download failed: %s", err)
+			}
+		}
+
+		// Use nickname instead of username if defined
+		if nick := b.mc.GetNickName(rmsg.UserID); nick != "" {
+			rmsg.Username = nick
+		}
+
+		messages <- rmsg
+	}
+}
+
+func (b *Bmattermost) handleMatterHook(messages chan *config.Message) {
+	for {
+		message := b.mh.Receive()
+		b.Log.Debugf("Receiving from matterhook %#v", message)
+		messages <- &config.Message{
+			UserID:   message.UserID,
+			Username: message.UserName,
+			Text:     message.Text,
+			Channel:  message.ChannelName,
+		}
+	}
+}
+
+// handleUploadFile handles native upload of files
+func (b *Bmattermost) handleUploadFile(msg *config.Message) (string, error) {
+	var err error
+	var res, id string
+	channelID := b.mc.GetChannelId(msg.Channel, b.TeamID)
+	for _, f := range msg.Extra["file"] {
+		fi := f.(config.FileInfo)
+		id, err = b.mc.UploadFile(*fi.Data, channelID, fi.Name)
+		if err != nil {
+			return "", err
+		}
+		msg.Text = fi.Comment
+		if b.GetBool("PrefixMessagesWithNick") {
+			msg.Text = msg.Username + msg.Text
+		}
+		res, err = b.mc.PostMessageWithFiles(channelID, msg.Text, []string{id})
+	}
+	return res, err
+}
+
+func (b *Bmattermost) handleProps(rmsg *config.Message, message *matterclient.Message) {
+	props := message.Post.Props
+	if props == nil {
+		return
+	}
+	if _, ok := props["override_username"].(string); ok {
+		rmsg.Username = props["override_username"].(string)
+	}
+	if _, ok := props["attachments"].([]interface{}); ok {
+		rmsg.Extra["attachments"] = props["attachments"].([]interface{})
+		if rmsg.Text == "" {
+			for _, attachment := range rmsg.Extra["attachments"] {
+				attach := attachment.(map[string]interface{})
+				if attach["text"].(string) != "" {
+					rmsg.Text += attach["text"].(string)
+					continue
+				}
+				if attach["fallback"].(string) != "" {
+					rmsg.Text += attach["fallback"].(string)
+				}
+			}
+		}
+	}
+}