feat: implement watch for monitoring chat messages

- Added a new command handler for /watch that allows users to listen to messages from a specified chat and save them according to storage rules.
- Introduced filtering options for messages using regular expressions.
- Implemented functionality to start and stop watching chats, including error handling for invalid inputs and user settings.
- Created a new utility package for message element handling related to the watch feature.
- Updated the user model to manage watched chats, including methods to add, remove, and check if a chat is being watched.

client/bot/handlers/register.go

@@ -1,12 +1,25 @@
 package handlers
 
 import (
+	"path"
+	"regexp"
+	"strings"
+
 	"github.com/celestix/gotgproto/dispatcher"
 	"github.com/celestix/gotgproto/dispatcher/handlers"
 	"github.com/celestix/gotgproto/dispatcher/handlers/filters"
 	"github.com/celestix/gotgproto/ext"
+	"github.com/charmbracelet/log"
 	"github.com/krau/SaveAny-Bot/client/bot/handlers/utils/re"
+	"github.com/krau/SaveAny-Bot/client/bot/handlers/utils/ruleutil"
+	userclient "github.com/krau/SaveAny-Bot/client/user"
+	"github.com/krau/SaveAny-Bot/common/utils/tgutil"
+	"github.com/krau/SaveAny-Bot/core"
+	"github.com/krau/SaveAny-Bot/core/tftask"
+	"github.com/krau/SaveAny-Bot/database"
 	"github.com/krau/SaveAny-Bot/pkg/tcbdata"
+	"github.com/krau/SaveAny-Bot/storage"
+	"github.com/rs/xid"
 )
 
 func Register(disp dispatcher.Dispatcher) {
@@ -23,6 +36,8 @@ func Register(disp dispatcher.Dispatcher) {
 	disp.AddHandler(handlers.NewCommand("storage", handleStorageCmd))
 	disp.AddHandler(handlers.NewCommand("dir", handleDirCmd))
 	disp.AddHandler(handlers.NewCommand("rule", handleRuleCmd))
+	disp.AddHandler(handlers.NewCommand("watch", handleWatchCmd))
+	disp.AddHandler(handlers.NewCommand("unwatch", handleUnwatchCmd))
 	disp.AddHandler(handlers.NewCommand("save", handleSilentMode(handleSaveCmd, handleSilentSaveReplied)))
 	disp.AddHandler(handlers.NewCallbackQuery(filters.CallbackQuery.Prefix(tcbdata.TypeAdd), handleAddCallback))
 	disp.AddHandler(handlers.NewCallbackQuery(filters.CallbackQuery.Prefix(tcbdata.TypeSetDefault), handleSetDefaultCallback))
@@ -38,4 +53,81 @@ func Register(disp dispatcher.Dispatcher) {
 	}
 	disp.AddHandler(handlers.NewMessage(telegraphUrlRegexFilter, handleSilentMode(handleTelegraphUrlMessage, handleSilentSaveTelegraph)))
 	disp.AddHandler(handlers.NewMessage(filters.Message.Media, handleSilentMode(handleMediaMessage, handleSilentSaveMedia)))
+
+	if userclient.GetClient() != nil {
+		go listenMediaMessageEvent(userclient.GetMediaMessageCh())
+	}
+}
+
+func listenMediaMessageEvent(ch chan userclient.MediaMessageEvent) {
+	logger := log.FromContext(userclient.GetCtx())
+	for event := range ch {
+		ctx := event.Ctx
+		file := event.File
+		chats, err := database.GetWatchChatsByChatID(ctx, event.ChatID)
+		if err != nil {
+			logger.Errorf("Failed to get watch chats for chat ID %d: %v", event.ChatID, err)
+			continue
+		}
+		msgText := event.File.Message().GetMessage()
+		for _, chat := range chats {
+			if chat.Filter != "" {
+				filter := strings.Split(chat.Filter, ":")
+				if len(filter) != 2 {
+					logger.Warnf("Invalid filter format in chat %d, skipping", chat.ChatID)
+					continue
+				}
+				filterType := filter[0]
+				filterData := filter[1]
+				switch filterType {
+				case "msgre":
+					if _, err := regexp.MatchString(filterData, msgText); err != nil {
+						continue
+					}
+				default:
+					logger.Warnf("Unsupported filter type %s in chat %d, skipping", filterType, chat.ChatID)
+					continue
+				}
+			}
+			user, err := database.GetUserByID(ctx, chat.UserID)
+			if err != nil {
+				logger.Errorf("Failed to get user by ID %d: %v", chat.UserID, err)
+				continue
+			}
+			if user.DefaultStorage == "" {
+				logger.Warnf("User %d has no default storage set, skipping media message handling", chat.UserID)
+				continue
+			}
+			stor, err := storage.GetStorageByUserIDAndName(ctx, user.ChatID, user.DefaultStorage)
+			if err != nil {
+				logger.Errorf("Failed to get storage by user ID %d and name %s: %v", user.ChatID, user.DefaultStorage, err)
+				continue
+			}
+			var dirPath string
+			if user.ApplyRule && user.Rules != nil {
+				matchedStorageName, matchedDirPath := ruleutil.ApplyRule(ctx, user.Rules, ruleutil.NewInput(file))
+				dirPath = matchedDirPath.String()
+				if matchedStorageName.IsUsable() {
+					stor, err = storage.GetStorageByUserIDAndName(ctx, user.ChatID, matchedStorageName.String())
+					if err != nil {
+						logger.Errorf("Failed to get storage by user ID and name: %s", err)
+						continue
+					}
+				}
+			}
+			storagePath := stor.JoinStoragePath(path.Join(dirPath, file.Name()))
+			injectCtx := tgutil.ExtWithContext(ctx.Context, ctx)
+			taskid := xid.New().String()
+			task, err := tftask.NewTGFileTask(taskid, injectCtx, file, stor, storagePath, nil)
+			if err != nil {
+				logger.Errorf("create task failed: %s", err)
+				continue
+			}
+			if err := core.AddTask(injectCtx, task); err != nil {
+				logger.Errorf("add task failed: %s", err)
+				continue
+			}
+			logger.Infof("Added media message task for user %d in chat %d: %s", chat.UserID, event.ChatID, file.Name())
+		}
+	}
 }