package repository

import (
	"database/sql"
	"errors"
	"log"
	domain "truck-company/internal/domain"
)

type AppRepo struct {
	db *sql.DB
}

func NewAppRepo(db *sql.DB) *AppRepo {
	return &AppRepo{
		db: db,
	}
}

func (r *AppRepo) GetAllRoutes() ([]domain.Route, error) {
	if r.db == nil {
		return nil, errors.New("Ошибка подключения к бд. *db == nil")
	}
	rows, err := r.db.Query("SELECT id, name, price FROM route")
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var routes []domain.Route

	for rows.Next() {
		var route domain.Route
		if err := rows.Scan(&route.ID, &route.Name, &route.Price); err != nil {
			return nil, err
		}
		routes = append(routes, route)
	}
	return routes, nil
}

func (r *AppRepo) GetTransportByRoute(routeID int64) ([]domain.Transport, error) {
	if r.db == nil {
		return nil, errors.New("Ошибка подключения к бд. *db == nil")
	}

	rows, err := r.db.Query(`
		SELECT t.id, t.model, t.capacity, tt.name
		FROM transport t
		JOIN shipment s ON t.id = s.transport_id
		JOIN transport_type tt ON t.type_id = tt.id
		WHERE s.route_id = $1`, routeID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var transports []domain.Transport
	for rows.Next() {
		var transport domain.Transport
		if err := rows.Scan(&transport.ID, &transport.Model, &transport.Capacity, &transport.Type); err != nil {
			return nil, err
		}
		transports = append(transports, transport)
	}
	return transports, nil
}

func (r *AppRepo) GetCargoCost(cargoID int64) (float64, error) {
	if r.db == nil {
		return 0, errors.New("Ошибка подключения к бд. *db == nil")
	}

	var finalCost float64
	query := `
		SELECT 
       SUM( CASE 
           WHEN cl.is_regular THEN s.cost * 0.95  -- 5% скидка постоянным клиентам
           ELSE s.cost 
       END) AS final_cost
      
		FROM shipment s
		JOIN client cl ON s.client_id = cl.id
		JOIN route r ON s.route_id = r.id
		JOIN cargo c ON s.cargo_id = c.id
		WHERE c.id = $1
		GROUP BY c.id;
`
	err := r.db.QueryRow(query, cargoID).Scan(&finalCost)
	if err != nil {
		log.Println("Ошибка при получении стоимости перевозки:", err)
		return 0, err
	}

	return finalCost, nil
}