feat: Implement log viewer and WebSocket logging

- Added a new log viewer component to display real-time logs.
- Integrated WebSocket support for broadcasting log entries to connected clients.
- Updated main application to initialize logging and handle log directory creation.
- Enhanced error handling for log loading and broadcasting.
- Introduced new routes for accessing the log viewer and WebSocket stream.

internal/web/handlers/handler.go

@@ -1,13 +1,30 @@
 package handlers
 
 import (
+	"fmt"
+	"os"
+	"sync"
 	"time"
 
+	"github.com/gorilla/websocket"
+	"github.com/starfleetcptn/gomft/components"
 	"github.com/starfleetcptn/gomft/internal/db"
 	"github.com/starfleetcptn/gomft/internal/email"
 	"github.com/starfleetcptn/gomft/internal/scheduler"
 )
 
+// WebSocketClients maintains the set of active WebSocket clients
+var WebSocketClients = make(map[*websocket.Conn]bool)
+
+// WebSocketClientsMutex protects the WebSocketClients map
+var WebSocketClientsMutex = &sync.Mutex{}
+
+// WebSocketClientWriteMutexes maintains individual write mutexes for each client
+var WebSocketClientWriteMutexes = make(map[*websocket.Conn]*sync.Mutex)
+
+// LogChannel is used to send log entries to all WebSocket clients
+var LogChannel = make(chan components.LogEntry, 512)
+
 // Handlers contains all the dependencies needed by the handlers
 type Handlers struct {
 	DB        *db.DB
@@ -22,7 +39,7 @@ type Handlers struct {
 
 // NewHandlers creates a new Handlers instance
 func NewHandlers(database *db.DB, scheduler scheduler.SchedulerInterface, jwtSecret string, dbPath string, backupDir string, logsDir string, emailService *email.Service) *Handlers {
-	return &Handlers{
+	h := &Handlers{
 		DB:        database,
 		Scheduler: scheduler,
 		JWTSecret: jwtSecret,
@@ -32,4 +49,112 @@ func NewHandlers(database *db.DB, scheduler scheduler.SchedulerInterface, jwtSec
 		LogsDir:   logsDir,
 		Email:     emailService,
 	}
+
+	// Start the WebSocket log broadcaster
+	StartLogBroadcaster()
+
+	return h
+}
+
+// StartLogBroadcaster starts a goroutine that broadcasts logs to all connected WebSocket clients
+func StartLogBroadcaster() {
+	go func() {
+		fmt.Fprintln(os.Stderr, "[DEBUG-BROADCASTER-V4] Broadcaster goroutine started.")
+		for {
+			logEntry := <-LogChannel // Wait for a log entry
+
+			WebSocketClientsMutex.Lock()
+			clientsToSend := make(map[*websocket.Conn]*sync.Mutex)
+			for client, mutex := range WebSocketClientWriteMutexes {
+				if _, exists := WebSocketClients[client]; exists {
+					clientsToSend[client] = mutex
+				}
+			}
+			WebSocketClientsMutex.Unlock()
+
+			if len(clientsToSend) == 0 {
+				continue // Skip if no clients
+			}
+
+			fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Received log. Broadcasting to %d clients. Level='%s', Src='%s'\n",
+				len(clientsToSend), logEntry.Level, logEntry.Source)
+
+			var wg sync.WaitGroup
+			for client, mutex := range clientsToSend {
+				wg.Add(1)
+				go func(c *websocket.Conn, m *sync.Mutex, entry components.LogEntry) {
+					defer wg.Done()
+
+					fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Attempting send to client %v\n", c.RemoteAddr())
+
+					// Lock only for this specific client's write
+					m.Lock()
+					// Set a deadline for the write operation
+					deadline := time.Now().Add(5 * time.Second) // 5-second deadline
+					err := c.SetWriteDeadline(deadline)
+					if err != nil {
+						fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Error setting write deadline for client %v: %v\n", c.RemoteAddr(), err)
+						// Don't unlock yet, proceed to cleanup
+					} else {
+						err = c.WriteJSON(entry)
+					}
+					m.Unlock() // Unlock after write attempt (or deadline error)
+
+					if err != nil {
+						fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Error writing to client %v: %v. Initiating removal.\n", c.RemoteAddr(), err)
+						WebSocketClientsMutex.Lock()
+						if _, stillExists := WebSocketClients[c]; stillExists {
+							delete(WebSocketClients, c)
+							delete(WebSocketClientWriteMutexes, c)
+							fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Removed client %v from maps.\n", c.RemoteAddr())
+						} else {
+							fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Client %v already removed by another process.\n", c.RemoteAddr())
+						}
+						WebSocketClientsMutex.Unlock()
+						c.Close() // Close the connection outside the lock
+					} else {
+						fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTER-V4] Successfully sent to client %v\n", c.RemoteAddr())
+					}
+				}(client, mutex, logEntry)
+			}
+			wg.Wait() // Wait for all sends in this batch to complete or fail
+		}
+	}()
+}
+
+// BroadcastLog sends a log entry to all connected WebSocket clients
+func (h *Handlers) BroadcastLog(level, message, source string) {
+	// NOTE: Level prefix parsing is now handled in logger.go/parseLogEntry
+
+	// Create log entry with UTC timestamp for consistency
+	logEntry := components.LogEntry{
+		Timestamp: time.Now().UTC(),
+		Level:     level,
+		Message:   message,
+		Source:    source,
+	}
+
+	// Get the current number of clients (avoid logging in case of recursive issues)
+	numClients := 0
+	WebSocketClientsMutex.Lock()
+	numClients = len(WebSocketClients)
+	WebSocketClientsMutex.Unlock()
+
+	// Only attempt to write to channel if there are clients
+	if numClients > 0 {
+		// *** DEBUG: Print channel send attempt ***
+		fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTLOG-V4] Attempting to send to LogChannel: Level='%s', Source='%s'\n", level, source)
+
+		// Try to send the log entry to the channel with a timeout
+		select {
+		case LogChannel <- logEntry:
+			// Successfully sent
+			fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTLOG-V4] Successfully sent to LogChannel.\n")
+		case <-time.After(100 * time.Millisecond):
+			// Channel is full or blocked, log and continue
+			fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTLOG-V4] Log channel timeout, discarding log entry: %s\n", message)
+		}
+	} else {
+		fmt.Fprintf(os.Stderr, "[DEBUG-BROADCASTLOG-V4] No clients connected, skipping send to LogChannel.\n")
+	}
 }