package db

import (
	"database/sql"
	"fmt"
	"lostcavewireplanner/internal/models"
)

func (s *Store) ConnectionTypeGetAll() ([]models.ConnectionType, error) {
	rows, err := s.DB.Query(`SELECT id, name FROM connection_types ORDER BY id`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var types []models.ConnectionType
	for rows.Next() {
		var ct models.ConnectionType
		if err := rows.Scan(&ct.ID, &ct.Name); err != nil {
			return nil, err
		}
		types = append(types, ct)
	}
	return types, rows.Err()
}

func (s *Store) ConnectionGetByPortID(portID int64) (*models.Connection, error) {
	c := &models.Connection{}
	err := s.DB.QueryRow(`SELECT id, connection_type_id, label_1, label_2, color, port_id_1, port_id_2, created_at, updated_at FROM connections WHERE port_id_1 = ? OR port_id_2 = ?`, portID, portID).
		Scan(&c.ID, &c.ConnectionTypeID, &c.Label1, &c.Label2, &c.Color, &c.PortID1, &c.PortID2, &c.CreatedAt, &c.UpdatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	s.populateConnection(c)
	return c, nil
}

func (s *Store) ConnectionGetByPortIDExcluding(portID int64, excludeConnID int64) (*models.Connection, error) {
	c := &models.Connection{}
	err := s.DB.QueryRow(`SELECT id, connection_type_id, label_1, label_2, color, port_id_1, port_id_2, created_at, updated_at FROM connections WHERE (port_id_1 = ? OR port_id_2 = ?) AND id != ?`, portID, portID, excludeConnID).
		Scan(&c.ID, &c.ConnectionTypeID, &c.Label1, &c.Label2, &c.Color, &c.PortID1, &c.PortID2, &c.CreatedAt, &c.UpdatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	s.populateConnection(c)
	return c, nil
}

func (s *Store) ConnectionGetByID(id int64) (*models.Connection, error) {
	c := &models.Connection{}
	err := s.DB.QueryRow(`SELECT id, connection_type_id, label_1, label_2, color, port_id_1, port_id_2, created_at, updated_at FROM connections WHERE id = ?`, id).
		Scan(&c.ID, &c.ConnectionTypeID, &c.Label1, &c.Label2, &c.Color, &c.PortID1, &c.PortID2, &c.CreatedAt, &c.UpdatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	s.populateConnection(c)
	return c, nil
}

func (s *Store) ConnectionGetAllForRack(rackID int64) ([]models.Connection, error) {
	rows, err := s.DB.Query(`
		SELECT c.id, c.connection_type_id, c.label_1, c.label_2, c.color, c.port_id_1, c.port_id_2, c.created_at, c.updated_at
		FROM connections c
		WHERE (port_id_1 IN (SELECT dp.id FROM device_ports dp JOIN devices d ON d.id = dp.device_id WHERE d.rack_id = ?))
		   OR (port_id_2 IN (SELECT dp.id FROM device_ports dp JOIN devices d ON d.id = dp.device_id WHERE d.rack_id = ?))`, rackID, rackID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var conns []models.Connection
	for rows.Next() {
		var c models.Connection
		if err := rows.Scan(&c.ID, &c.ConnectionTypeID, &c.Label1, &c.Label2, &c.Color, &c.PortID1, &c.PortID2, &c.CreatedAt, &c.UpdatedAt); err != nil {
			return nil, err
		}
		s.populateConnection(&c)
		conns = append(conns, c)
	}
	return conns, rows.Err()
}

func (s *Store) ConnectionGetAll() ([]models.Connection, error) {
	rows, err := s.DB.Query(`SELECT id, connection_type_id, label_1, label_2, color, port_id_1, port_id_2, created_at, updated_at FROM connections`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var conns []models.Connection
	for rows.Next() {
		var c models.Connection
		if err := rows.Scan(&c.ID, &c.ConnectionTypeID, &c.Label1, &c.Label2, &c.Color, &c.PortID1, &c.PortID2, &c.CreatedAt, &c.UpdatedAt); err != nil {
			return nil, err
		}
		conns = append(conns, c)
	}
	return conns, rows.Err()
}

func (s *Store) ConnectionCreate(c *models.Connection) error {
	tx, err := s.DB.Begin()
	if err != nil {
		return err
	}
	defer tx.Rollback()

	if c.PortID1 != nil {
		exists, err := s.portConnectedTx(tx, *c.PortID1)
		if err != nil {
			return err
		}
		if exists {
			return fmt.Errorf("port %d is already connected", *c.PortID1)
		}
	}
	if c.PortID2 != nil {
		exists, err := s.portConnectedTx(tx, *c.PortID2)
		if err != nil {
			return err
		}
		if exists {
			return fmt.Errorf("port %d is already connected", *c.PortID2)
		}
	}

	res, err := tx.Exec(`INSERT INTO connections (connection_type_id, label_1, label_2, color, port_id_1, port_id_2) VALUES (?, ?, ?, ?, ?, ?)`,
		c.ConnectionTypeID, c.Label1, c.Label2, c.Color, c.PortID1, c.PortID2)
	if err != nil {
		return err
	}
	c.ID, err = res.LastInsertId()
	if err != nil {
		return err
	}
	return tx.Commit()
}

func (s *Store) ConnectionUpdate(c *models.Connection) error {
	_, err := s.DB.Exec(`UPDATE connections SET connection_type_id=?, label_1=?, label_2=?, color=?, port_id_1=?, port_id_2=?, updated_at=datetime('now') WHERE id=?`,
		c.ConnectionTypeID, c.Label1, c.Label2, c.Color, c.PortID1, c.PortID2, c.ID)
	return err
}

func (s *Store) ConnectionDelete(id int64) error {
	_, err := s.DB.Exec(`DELETE FROM connections WHERE id=?`, id)
	return err
}

func (s *Store) portConnectedTx(tx *sql.Tx, portID int64) (bool, error) {
	var count int
	err := tx.QueryRow(`SELECT COUNT(*) FROM connections WHERE port_id_1 = ? OR port_id_2 = ?`, portID, portID).Scan(&count)
	return count > 0, err
}

func (s *Store) populateConnection(c *models.Connection) {
	if c.PortID1 != nil {
		c.Port1, _ = s.PortGetByID(*c.PortID1)
		if c.Port1 != nil {
			c.Device1, _ = s.DeviceGetByID(c.Port1.DeviceID)
		}
	}
	if c.PortID2 != nil {
		c.Port2, _ = s.PortGetByID(*c.PortID2)
		if c.Port2 != nil {
			c.Device2, _ = s.DeviceGetByID(c.Port2.DeviceID)
		}
	}
	ct, _ := s.ConnectionTypeGetByID(c.ConnectionTypeID)
	c.ConnectionType = ct
}

func (s *Store) ConnectionTypeGetByID(id int64) (*models.ConnectionType, error) {
	ct := &models.ConnectionType{}
	err := s.DB.QueryRow(`SELECT id, name FROM connection_types WHERE id = ?`, id).Scan(&ct.ID, &ct.Name)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return ct, nil
}