feat: filter receive messages by since

internal/isphere/source.go

@@ -3,7 +3,9 @@ package isphere
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"strings"
+	"time"
 
 	"isphere-ai-bridge/internal/isphere/logcodec"
 	"isphere-ai-bridge/internal/isphere/packetlog"
@@ -25,6 +27,7 @@ type Message struct {
 type ReceiveMessagesQuery struct {
 	ConversationID string
 	Query          string
+	Since          string
 	Limit          int
 }
 
@@ -37,6 +40,10 @@ type EncryptedPacketLogSource struct {
 }
 
 func (s EncryptedPacketLogSource) ReceiveMessages(ctx context.Context, query ReceiveMessagesQuery) (ReceiveMessagesResult, error) {
+	since, hasSince, err := parseReceiveMessagesSince(query.Since)
+	if err != nil {
+		return ReceiveMessagesResult{}, err
+	}
 	limit := query.Limit
 	if limit <= 0 || limit > len(s.Lines) {
 		limit = len(s.Lines)
@@ -57,7 +64,7 @@ func (s EncryptedPacketLogSource) ReceiveMessages(ctx context.Context, query Rec
 			return ReceiveMessagesResult{}, fmt.Errorf("parse packet log line %d: %w", index, err)
 		}
 		message := normalizePacketMessage(parsed)
-		if !receiveMessageMatchesQuery(message, query) {
+		if !receiveMessageMatchesQuery(message, query) || !receiveMessageMatchesSince(message, since, hasSince) {
 			continue
 		}
 		messages = append(messages, message)
@@ -68,6 +75,18 @@ func (s EncryptedPacketLogSource) ReceiveMessages(ctx context.Context, query Rec
 	return ReceiveMessagesResult{Messages: messages}, nil
 }
 
+func parseReceiveMessagesSince(value string) (time.Time, bool, error) {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return time.Time{}, false, nil
+	}
+	parsed, err := time.Parse(time.RFC3339Nano, trimmed)
+	if err != nil {
+		return time.Time{}, false, fmt.Errorf("parse receive messages since %q: %w", value, err)
+	}
+	return parsed.UTC(), true, nil
+}
+
 func receiveMessageMatchesQuery(message Message, query ReceiveMessagesQuery) bool {
 	if strings.TrimSpace(query.ConversationID) != "" && message.ConversationID != strings.TrimSpace(query.ConversationID) {
 		return false
@@ -93,6 +112,32 @@ func receiveMessageMatchesQuery(message Message, query ReceiveMessagesQuery) boo
 	return false
 }
 
+func receiveMessageMatchesSince(message Message, since time.Time, hasSince bool) bool {
+	if !hasSince {
+		return true
+	}
+	messageTime, ok := packetMessageTimestamp(message.Timestamp)
+	if !ok {
+		return false
+	}
+	return !messageTime.Before(since)
+}
+
+func packetMessageTimestamp(value string) (time.Time, bool) {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return time.Time{}, false
+	}
+	epoch, err := strconv.ParseInt(trimmed, 10, 64)
+	if err != nil {
+		return time.Time{}, false
+	}
+	if epoch > 1_000_000_000_000 {
+		return time.UnixMilli(epoch).UTC(), true
+	}
+	return time.Unix(epoch, 0).UTC(), true
+}
+
 func normalizePacketMessage(msg packetlog.Message) Message {
 	sender := bareJID(msg.From)
 	receiver := bareJID(msg.To)