Add full monorepo: virtual-banker, backend, frontend, docs, scripts, deployment

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/api/labels/labels.go

@@ -0,0 +1,73 @@
+package labels
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// LabelService handles address labeling
+type LabelService struct {
+	db *pgxpool.Pool
+}
+
+// NewLabelService creates a new label service
+func NewLabelService(db *pgxpool.Pool) *LabelService {
+	return &LabelService{db: db}
+}
+
+// AddLabel adds a label to an address
+func (l *LabelService) AddLabel(ctx context.Context, chainID int, address, label, labelType string, userID *string) error {
+	query := `
+		INSERT INTO address_labels (chain_id, address, label, label_type, user_id)
+		VALUES ($1, $2, $3, $4, $5)
+		ON CONFLICT (chain_id, address, label_type, user_id) DO UPDATE SET
+			label = $3,
+			updated_at = NOW()
+	`
+
+	_, err := l.db.Exec(ctx, query, chainID, address, label, labelType, userID)
+	return err
+}
+
+// GetLabels gets labels for an address
+func (l *LabelService) GetLabels(ctx context.Context, chainID int, address string) ([]Label, error) {
+	query := `
+		SELECT label, label_type, user_id, source, created_at
+		FROM address_labels
+		WHERE chain_id = $1 AND address = $2
+		ORDER BY created_at DESC
+	`
+
+	rows, err := l.db.Query(ctx, query, chainID, address)
+	if err != nil {
+		return nil, fmt.Errorf("failed to query labels: %w", err)
+	}
+	defer rows.Close()
+
+	var labels []Label
+	for rows.Next() {
+		var label Label
+		var userID *string
+		if err := rows.Scan(&label.Label, &label.LabelType, &userID, &label.Source, &label.CreatedAt); err != nil {
+			continue
+		}
+		if userID != nil {
+			label.UserID = *userID
+		}
+		labels = append(labels, label)
+	}
+
+	return labels, nil
+}
+
+// Label represents an address label
+type Label struct {
+	Label     string
+	LabelType string
+	UserID    string
+	Source    string
+	CreatedAt string
+}
+