refactor: restructure in entirety

internal/database/buyer.go

@@ -0,0 +1,63 @@
+package database
+
+import (
+	"billit/internal/models"
+	"database/sql"
+	"fmt"
+	"time"
+)
+
+// CreateBuyerDetails creates a new buyer details entry
+func (s *service) CreateBuyerDetails(userID string, name string, details string) (*models.BuyerDetails, error) {
+	id := fmt.Sprintf("%d", time.Now().UnixNano())
+	_, err := s.db.Exec(`INSERT INTO buyer_details (id, user_id, name, details) VALUES (?, ?, ?, ?)`, id, userID, name, details)
+	if err != nil {
+		return nil, err
+	}
+	return s.GetBuyerDetails(id, userID)
+}
+
+// UpdateBuyerDetails updates an existing buyer details entry
+func (s *service) UpdateBuyerDetails(id string, userID string, name string, details string) error {
+	_, err := s.db.Exec(`UPDATE buyer_details SET name = ?, details = ? WHERE id = ? AND user_id = ?`, name, details, id, userID)
+	return err
+}
+
+// GetBuyerDetails retrieves a buyer details entry by ID
+func (s *service) GetBuyerDetails(id string, userID string) (*models.BuyerDetails, error) {
+	var b models.BuyerDetails
+	err := s.db.QueryRow(`SELECT id, user_id, name, details, created_at FROM buyer_details WHERE id = ? AND user_id = ?`, id, userID).
+		Scan(&b.ID, &b.UserID, &b.Name, &b.Details, &b.CreatedAt)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &b, nil
+}
+
+// GetAllBuyerDetails retrieves all buyer details for a user
+func (s *service) GetAllBuyerDetails(userID string) ([]models.BuyerDetails, error) {
+	rows, err := s.db.Query(`SELECT id, user_id, name, details, created_at FROM buyer_details WHERE user_id = ? ORDER BY name`, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var buyers []models.BuyerDetails
+	for rows.Next() {
+		var b models.BuyerDetails
+		if err := rows.Scan(&b.ID, &b.UserID, &b.Name, &b.Details, &b.CreatedAt); err != nil {
+			return nil, err
+		}
+		buyers = append(buyers, b)
+	}
+	return buyers, nil
+}
+
+// DeleteBuyerDetails removes a buyer details entry
+func (s *service) DeleteBuyerDetails(id string, userID string) error {
+	_, err := s.db.Exec(`DELETE FROM buyer_details WHERE id = ? AND user_id = ?`, id, userID)
+	return err
+}