second commit

internal/handler/webhook/line_webhook.go

@@ -0,0 +1,133 @@
+package webhook
+
+// LineWebhookHandler processes incoming LINE webhook HTTP requests via Gin.
+// Reference: Facebook webhook adapter pattern (facebook_webhook.go)
+//
+// URL pattern: /webhooks/line/:inbox_id
+// Method: POST (LINE Messaging API sends events as JSON)
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"strconv"
+
+	linechannel "github.com/gochat/gochat/internal/channel/line"
+	"github.com/gochat/gochat/internal/model"
+	applogger "github.com/gochat/gochat/pkg/logger"
+
+	"github.com/gin-gonic/gin"
+	"gorm.io/gorm"
+)
+
+// LineWebhookHandler processes LINE webhook requests via Gin.
+type LineWebhookHandler struct {
+	lineWebhook *linechannel.WebhookHandler
+	pipeline    *linechannel.IncomingProcessor
+	service     *linechannel.LineService
+	db          *gorm.DB
+}
+
+// NewLineWebhookHandler creates a LINE webhook handler for Gin integration.
+func NewLineWebhookHandler(lineWebhook *linechannel.WebhookHandler, pipeline *linechannel.IncomingProcessor, service *linechannel.LineService, db *gorm.DB) *LineWebhookHandler {
+	return &LineWebhookHandler{
+		lineWebhook: lineWebhook,
+		pipeline:    pipeline,
+		service:     service,
+		db:          db,
+	}
+}
+
+// HandleLineWebhook processes an incoming LINE webhook Gin request.
+func (h *LineWebhookHandler) HandleLineWebhook(c *gin.Context) {
+	inboxIDStr := c.Param("inbox_id")
+	inboxID, err := strconv.ParseUint(inboxIDStr, 10, 32)
+	if err != nil {
+		applogger.L().Warnf("LINE webhook: invalid inbox_id %s", inboxIDStr)
+		c.JSON(http.StatusOK, gin.H{"status": "ignored"})
+		return
+	}
+
+	// Lookup inbox from database
+	inbox, err := h.lookupInbox(uint(inboxID))
+	if err != nil {
+		applogger.L().Warnf("LINE webhook: inbox lookup failed for id %d: %v", inboxID, err)
+		c.JSON(http.StatusOK, gin.H{"status": "ignored"})
+		return
+	}
+
+	// Read request body
+	body, err := io.ReadAll(c.Request.Body)
+	if err != nil {
+		applogger.L().Errorf("LINE webhook: failed to read body for inbox %d: %v", inboxID, err)
+		c.JSON(http.StatusOK, gin.H{"status": "ignored"})
+		return
+	}
+	defer c.Request.Body.Close()
+
+	// Verify webhook signature
+	config := h.parseChannelConfig(inbox)
+	channelSecret := ""
+	if v, ok := config["channel_secret"].(string); ok {
+		channelSecret = v
+	}
+	signature := c.GetHeader("X-Line-Signature")
+
+	if channelSecret != "" && signature != "" {
+		if !h.service.VerifySignature(channelSecret, string(body), signature) {
+			applogger.L().Warnf("LINE webhook: invalid signature for inbox=%d", inboxID)
+			c.JSON(http.StatusUnauthorized, gin.H{"error": "invalid signature"})
+			return
+		}
+	}
+
+	// Parse webhook event
+	var webhookEvent linechannel.WebhookEvent
+	if err := json.Unmarshal(body, &webhookEvent); err != nil {
+		applogger.L().Errorf("LINE webhook: failed to parse JSON for inbox %d: %v", inboxID, err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid JSON"})
+		return
+	}
+
+	// Process each event via the pipeline
+	for _, event := range webhookEvent.Events {
+		incomingMsg, err := h.pipeline.ProcessEvent(c.Request.Context(), inbox, event)
+		if err != nil {
+			applogger.L().Errorf("LINE webhook: process event failed for inbox %d: %v", inboxID, err)
+			continue
+		}
+		if incomingMsg != nil {
+			applogger.L().Debugf("LINE webhook: processed event type=%s sender=%s",
+				event.Type, incomingMsg.SenderID)
+		}
+	}
+
+	c.JSON(http.StatusOK, gin.H{"status": "processed"})
+}
+
+// HandleLineVerification responds to LINE webhook URL verification.
+func (h *LineWebhookHandler) HandleLineVerification(c *gin.Context) {
+	c.JSON(http.StatusOK, gin.H{"status": "verified"})
+}
+
+// lookupInbox fetches an Inbox record from the database.
+func (h *LineWebhookHandler) lookupInbox(inboxID uint) (*model.Inbox, error) {
+	var inbox model.Inbox
+	if err := h.db.Where("id = ?", inboxID).First(&inbox).Error; err != nil {
+		return nil, err
+	}
+	return &inbox, nil
+}
+
+// parseChannelConfig parses the JSON-encoded ChannelConfig string into a map.
+func (h *LineWebhookHandler) parseChannelConfig(inbox *model.Inbox) map[string]interface{} {
+	if inbox.ChannelConfig == "" {
+		return map[string]interface{}{}
+	}
+	var config map[string]interface{}
+	if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
+		applogger.L().Warnf("LINE: Failed to parse ChannelConfig for inbox %d: %v", inbox.ID, err)
+		return map[string]interface{}{}
+	}
+	return config
+}