feat: add Gotify support to sendMsg handler

- Add sendGotify method to send notifications to Gotify server
- Support format: 'gotify' in SendMsgRequest
- Extract message ID from Gotify response
- Configurable via GOTIFY_URL and GOTIFY_TOKEN env vars
- Fallback graceful error if Gotify not configured

internal/notification/handler.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"net/smtp"
 	"os"
+	"strings"
 )
 
 // SendMsgRequest represents a sendMsg API request.
@@ -78,6 +79,8 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		resp = h.sendEmail(req)
 	case "sms":
 		resp = h.sendSMS(req)
+	case "gotify":
+		resp = h.sendGotify(req)
 	default:
 		resp = SendMsgResponse{
 			Status: "error",
@@ -158,3 +161,72 @@ func (h *Handler) sendSMS(req SendMsgRequest) SendMsgResponse {
 		Error:  "SMS not implemented yet",
 	}
 }
+
+// sendGotify sends a notification via Gotify server.
+func (h *Handler) sendGotify(req SendMsgRequest) SendMsgResponse {
+	if h.gotifyURL == "" || h.gotifyToken == "" {
+		return SendMsgResponse{
+			Status: "error",
+			Error:  "Gotify not configured (missing GOTIFY_URL or GOTIFY_TOKEN)",
+		}
+	}
+
+	// Construct Gotify message
+	gotifyReq := map[string]interface{}{
+		"title":    req.Title,
+		"message":  req.Message,
+		"priority": req.Priority,
+	}
+
+	// Marshal to JSON
+	body, err := json.Marshal(gotifyReq)
+	if err != nil {
+		log.Printf("error marshaling Gotify request: %v", err)
+		return SendMsgResponse{
+			Status: "error",
+			Error:  "failed to marshal request: " + err.Error(),
+		}
+	}
+
+	// POST to Gotify
+	gotifyEndpoint := fmt.Sprintf("%s/message?token=%s", h.gotifyURL, h.gotifyToken)
+	resp, err := http.Post(gotifyEndpoint, "application/json", strings.NewReader(string(body)))
+	if err != nil {
+		log.Printf("error sending to Gotify: %v", err)
+		return SendMsgResponse{
+			Status: "error",
+			Error:  "failed to send to Gotify: " + err.Error(),
+		}
+	}
+	defer resp.Body.Close()
+
+	// Check response status
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusCreated {
+		log.Printf("Gotify returned status %d", resp.StatusCode)
+		return SendMsgResponse{
+			Status: "error",
+			Error:  fmt.Sprintf("Gotify returned status %d", resp.StatusCode),
+		}
+	}
+
+	// Parse response
+	var gotifyResp map[string]interface{}
+	if err := json.NewDecoder(resp.Body).Decode(&gotifyResp); err != nil {
+		log.Printf("error decoding Gotify response: %v", err)
+		return SendMsgResponse{
+			Status: "success",
+			MessageID: "gotify-sent",
+		}
+	}
+
+	// Extract message ID if available
+	msgID := "gotify-sent"
+	if id, ok := gotifyResp["id"]; ok {
+		msgID = fmt.Sprintf("gotify-%v", id)
+	}
+
+	return SendMsgResponse{
+		Status:    "success",
+		MessageID: msgID,
+	}
+}