package storage

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"os"
	"strconv"

	"ariga.io/atlas/sql/postgres"
	"ariga.io/atlas/sql/schema"
	"github.com/lib/pq"
	_ "github.com/lib/pq"
	"github.com/spf13/viper"
)

type PostgresqlStorage struct {
	DbConnection *sql.DB
	Schema       string
	Tables       map[string]string
}

func NewPostgresqlStorage(cfg *viper.Viper) (PostgresqlStorage, error) {
	var (
		host             = cfg.GetString("storage.db.psql.host")
		port             = cfg.GetString("storage.db.psql.port")
		user             = cfg.GetString("storage.db.psql.user")
		password         = cfg.GetString("storage.db.psql.password")
		dbname           = cfg.GetString("storage.db.psql.dbname")
		sslmode          = cfg.GetString("storage.db.psql.sslmode")
		pg_schema        = cfg.GetString("storage.db.psql.schema")
		pgtables_vehicle = cfg.GetString("storage.db.psql.tables.vehicle")
		pgtables_booking = cfg.GetString("storage.db.psql.tables.booking")
		timezone         = "Europe/Paris"
	)
	portInt, _ := strconv.Atoi(port)
	psqlconn := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=%s TimeZone=%s", host, portInt,
		user, password, dbname, sslmode, timezone)
	db, err := sql.Open("postgres", psqlconn)
	if err != nil {
		fmt.Println("error", err)
		return PostgresqlStorage{}, fmt.Errorf("connection to postgresql failed")
	}
	err = db.Ping()
	if err != nil {
		fmt.Println(err)
		return PostgresqlStorage{}, fmt.Errorf("connection to postgresql database failed")
	}
	return PostgresqlStorage{
		DbConnection: db,
		Schema:       pg_schema,
		Tables: map[string]string{
			"vehicle": fmt.Sprintf("%s.%s", pg_schema, pgtables_vehicle),
			"booking": fmt.Sprintf("%s.%s", pg_schema, pgtables_booking),
		},
	}, nil
}

func (psql PostgresqlStorage) CreateVehicle(vehicle Vehicle) error {
	tx, err := psql.DbConnection.Begin()
	if err != nil {
		return fmt.Errorf("failed to begin transaction: %w", err)
	}
	vehicleQuery := fmt.Sprintf(`
		INSERT INTO %s (id, type, namespace, administrators, data, metadata)
		VALUES ($1, $2, $3, $4, $5, $6)
	`, psql.Tables["vehicle"])
	data, err := json.Marshal(vehicle.Data)
	if err != nil {
		return err
	}
	metadata, err := json.Marshal(vehicle.Metadata)
	if err != nil {
		return err
	}
	_, err = tx.Exec(vehicleQuery, vehicle.ID, vehicle.Type, vehicle.Namespace, pq.Array(vehicle.Administrators),
		data, metadata)
	if err != nil {
		tx.Rollback()
		return fmt.Errorf("failed to insert vehicle: %w", err)
	}
	bookingQuery := fmt.Sprintf(`
			INSERT INTO %s (id, vehicleid, driver, startdate, enddate, unavailablefrom, unavailableto, data, deleted)
			VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
		`, psql.Tables["booking"])

	for _, booking := range vehicle.Bookings {
		dataBooking, err := json.Marshal(booking.Data)
		if err != nil {
			return err
		}
		_, err = tx.Exec(bookingQuery, booking.ID, booking.Vehicleid, booking.Driver,
			booking.Startdate, booking.Enddate, booking.Unavailablefrom, booking.Unavailableto,
			dataBooking, booking.Deleted)
		if err != nil {
			tx.Rollback()
			return fmt.Errorf("failed to insert booking: %w", err)
		}
	}
	err = tx.Commit()
	if err != nil {
		tx.Rollback()
		return fmt.Errorf("failed to commit transaction: %w", err)
	}
	return nil
}

func (psql PostgresqlStorage) GetVehicle(id string) (*Vehicle, error) {
	vehicle := &Vehicle{}
	var vehicleData []byte
	var vehicleMetadata []byte
	query := fmt.Sprintf(`
		SELECT id, type, namespace, administrators, data, metadata
		FROM %s
		WHERE id = $1
	`, psql.Tables["vehicle"])

	err := psql.DbConnection.QueryRow(query, id).Scan(
		&vehicle.ID,
		&vehicle.Type,
		&vehicle.Namespace,
		pq.Array(&vehicle.Administrators),
		&vehicleData,
		&vehicleMetadata,
	)
	err = json.Unmarshal(vehicleData, &vehicle.Data)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal vehicle data")
	}
	err = json.Unmarshal(vehicleMetadata, &vehicle.Metadata)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal vehicle metadata")
	}
	if err != nil {
		if err == sql.ErrNoRows {
			return nil, fmt.Errorf("vehicle not found")
		}
		return nil, fmt.Errorf("failed to query database: %w", err)
	}

	return vehicle, nil
}

func (psql PostgresqlStorage) GetVehicles(namespaces []string) ([]Vehicle, error) {
	var vehicles []Vehicle
	if len(namespaces) == 0 {
		return vehicles, nil
	}

	query := fmt.Sprintf(`
    SELECT id, type, namespace, administrators, data, metadata
    FROM %s 
    WHERE namespace = ANY($1)
`, psql.Tables["vehicle"])

	rows, err := psql.DbConnection.Query(query, pq.Array(namespaces))
	if err != nil {
		return nil, fmt.Errorf("failed to query database: %w", err)
	}
	defer rows.Close()

	for rows.Next() {
		var vehicle Vehicle
		var administrators []string
		var vehicleData []byte
		var vehicleMetadata []byte

		scanArgs := []interface{}{
			&vehicle.ID,
			&vehicle.Type,
			&vehicle.Namespace,
			pq.Array(&administrators),
			&vehicleData,
			&vehicleMetadata,
		}

		err := rows.Scan(scanArgs...)
		if err != nil {
			return nil, fmt.Errorf("failed to scan row: %w", err)
		}

		vehicle.Administrators = administrators
		err = json.Unmarshal(vehicleData, &vehicle.Data)
		if err != nil {
			return nil, err
		}
		err = json.Unmarshal(vehicleMetadata, &vehicle.Metadata)
		if err != nil {
			return nil, err
		}

		vehicles = append(vehicles, vehicle)
	}

	if err := rows.Err(); err != nil {
		return nil, fmt.Errorf("unexpected error after iterating rows: %w", err)
	}

	return vehicles, nil
}

func (psql PostgresqlStorage) CreateBooking(booking Booking) error {
	query := fmt.Sprintf(`
		INSERT INTO %s (id, vehicleid, driver, startdate, enddate, unavailablefrom, unavailableto, data, deleted)
		VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
	`, psql.Tables["booking"])

	bookingData, err := json.Marshal(booking.Data)
	if err != nil {
		return fmt.Errorf("failed to marshal booking data: %w", err)
	}

	_, err = psql.DbConnection.Exec(query, booking.ID, booking.Vehicleid, booking.Driver, booking.Startdate,
		booking.Enddate, booking.Unavailablefrom, booking.Unavailableto, bookingData, booking.Deleted)
	if err != nil {
		return fmt.Errorf("failed to insert booking record: %w", err)
	}
	return nil
}

func (psql PostgresqlStorage) UpdateBooking(bookingToUpdate Booking) error {
	query := fmt.Sprintf(`
		UPDATE %s SET
			driver = $1,
			startdate = $2,
			enddate = $3,
			unavailablefrom = $4,
			unavailableto = $5,
			data = $6,
			deleted = $7
		WHERE id = $8
	`, psql.Tables["booking"])

	bookingData, err := json.Marshal(bookingToUpdate.Data)
	if err != nil {
		return fmt.Errorf("failed to marshal booking data: %w", err)
	}

	_, err = psql.DbConnection.Exec(
		query,
		bookingToUpdate.Driver,
		bookingToUpdate.Startdate,
		bookingToUpdate.Enddate,
		bookingToUpdate.Unavailablefrom,
		bookingToUpdate.Unavailableto,
		bookingData,
		bookingToUpdate.Deleted,
		bookingToUpdate.ID,
	)

	if err != nil {
		return fmt.Errorf("failed to update booking: %w", err)
	}

	return nil
}
func (psql PostgresqlStorage) GetBooking(id string) (*Booking, error) {
	booking := &Booking{}

	query := fmt.Sprintf(`
		SELECT b.id, b.vehicleid, b.driver, b.startdate, b.enddate,
		       b.unavailablefrom, b.unavailableto, b.data, b.deleted,
		       v.id, v.type, v.namespace, v.administrators, v.data, v.metadata
		FROM %s b
		LEFT JOIN %s v ON b.vehicleid = v.id
		WHERE b.id = $1
	`, psql.Tables["booking"], psql.Tables["vehicle"])

	row := psql.DbConnection.QueryRow(query, id)

	var administrators []string
	var bookingData []byte
	var vehicleData []byte
	var vehicleMetadata []byte

	err := row.Scan(
		&booking.ID,
		&booking.Vehicleid,
		&booking.Driver,
		&booking.Startdate,
		&booking.Enddate,
		&booking.Unavailablefrom,
		&booking.Unavailableto,
		&bookingData,
		&booking.Deleted,
		&booking.Vehicle.ID,
		&booking.Vehicle.Type,
		&booking.Vehicle.Namespace,
		pq.Array(&administrators),
		&vehicleData,
		&vehicleMetadata,
	)

	if err != nil {
		return nil, fmt.Errorf("error receiving booking: %w", err)
	}

	err = json.Unmarshal(bookingData, &booking.Data)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal booking data: %w", err)
	}

	err = json.Unmarshal(vehicleData, &booking.Vehicle.Data)
	if err != nil {
		return nil, err
	}
	err = json.Unmarshal(vehicleMetadata, &booking.Vehicle.Metadata)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal vehicle metadata: %w", err)
	}

	booking.Vehicle.Administrators = administrators

	return booking, nil
}

func (psql PostgresqlStorage) GetBookings() ([]Booking, error) {
	var bookings []Booking

	query := fmt.Sprintf(`
		SELECT b.id, b.vehicleid, b.driver, b.startdate, b.enddate,
		       b.unavailablefrom, b.unavailableto, b.data, b.deleted,
		       v.id, v.type, v.namespace, v.administrators, v.data, v.metadata
		FROM %s b
		LEFT JOIN %s v ON b.vehicleid = v.id
	`, psql.Tables["booking"], psql.Tables["vehicle"])

	rows, err := psql.DbConnection.Query(query)
	if err != nil {
		return nil, fmt.Errorf("failed to retrieve bookings: %w", err)
	}

	defer rows.Close()

	for rows.Next() {
		var booking Booking

		var administrators []string
		var bookingData []byte
		var vehicleData []byte
		var vehicleMetadata []byte

		err = rows.Scan(
			&booking.ID,
			&booking.Vehicleid,
			&booking.Driver,
			&booking.Startdate,
			&booking.Enddate,
			&booking.Unavailablefrom,
			&booking.Unavailableto,
			&bookingData,
			&booking.Deleted,
			&booking.Vehicle.ID,
			&booking.Vehicle.Type,
			&booking.Vehicle.Namespace,
			pq.Array(&administrators),
			&vehicleData,
			&vehicleMetadata,
		)

		if err != nil {
			return nil, fmt.Errorf("error receiving booking: %w", err)
		}

		err = json.Unmarshal(bookingData, &booking.Data)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal booking data: %w", err)
		}

		err = json.Unmarshal(vehicleData, &booking.Vehicle.Data)
		if err != nil {
			return nil, err
		}

		err = json.Unmarshal(vehicleMetadata, &booking.Vehicle.Metadata)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal vehicle metadata: %w", err)
		}

		booking.Vehicle.Administrators = administrators

		bookings = append(bookings, booking)
	}

	if err = rows.Err(); err != nil {
		return nil, fmt.Errorf("failed to retrieve bookings: %w", err)
	}

	return bookings, nil
}
func (psql PostgresqlStorage) GetBookingsForVehicle(vehicleid string) ([]Booking, error) {
	var bookings []Booking

	query := fmt.Sprintf(`
		SELECT b.id, b.vehicleid, b.driver, b.startdate, b.enddate,
		       b.unavailablefrom, b.unavailableto, b.data, b.deleted,
		       v.id, v.type, v.namespace, v.administrators, v.data, v.metadata
		FROM %s b
		LEFT JOIN %s v ON b.vehicleid = v.id
		WHERE b.vehicleid = $1
	`, psql.Tables["booking"], psql.Tables["vehicle"])

	rows, err := psql.DbConnection.Query(query, vehicleid)
	if err != nil {
		return nil, fmt.Errorf("error retrieving bookings for vehicle: %w", err)
	}

	for rows.Next() {
		var administrators []string
		var bookingData []byte
		var vehicleData []byte
		var vehicleMetadata []byte
		var booking Booking

		err := rows.Scan(
			&booking.ID,
			&booking.Vehicleid,
			&booking.Driver,
			&booking.Startdate,
			&booking.Enddate,
			&booking.Unavailablefrom,
			&booking.Unavailableto,
			&bookingData,
			&booking.Deleted,
			&booking.Vehicle.ID,
			&booking.Vehicle.Type,
			&booking.Vehicle.Namespace,
			pq.Array(&administrators),
			&vehicleData,
			&vehicleMetadata,
		)

		if err != nil {
			return nil, fmt.Errorf("error scanning booking row: %w", err)
		}

		err = json.Unmarshal(bookingData, &booking.Data)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal booking data: %w", err)
		}

		err = json.Unmarshal(vehicleData, &booking.Vehicle.Data)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal vehicle data: %w", err)
		}

		err = json.Unmarshal(vehicleMetadata, &booking.Vehicle.Metadata)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal vehicle metadata: %w", err)
		}

		booking.Vehicle.Administrators = administrators
		bookings = append(bookings, booking)
	}

	if err := rows.Err(); err != nil {
		return nil, fmt.Errorf("error iterating over booking rows: %w", err)
	}

	return bookings, nil
}
func (psql PostgresqlStorage) GetBookingsForDriver(driver string) ([]Booking, error) {
	bookings := []Booking{}

	query := fmt.Sprintf(`
		SELECT b.id, b.vehicleid, b.driver, b.startdate, b.enddate,
		       b.unavailablefrom, b.unavailableto, b.data, b.deleted,
		       v.id, v.type, v.namespace, v.administrators, v.data, v.metadata
		FROM %s b
		LEFT JOIN %s v ON b.vehicleid = v.id
		WHERE b.driver = $1
	`, psql.Tables["booking"], psql.Tables["vehicle"])

	rows, err := psql.DbConnection.Query(query, driver)
	if err != nil {
		return nil, fmt.Errorf("error querying bookings: %w", err)
	}

	defer rows.Close()

	for rows.Next() {
		booking := Booking{}
		var administrators []string
		var bookingData []byte
		var vehicleData []byte
		var vehicleMetadata []byte

		err = rows.Scan(
			&booking.ID,
			&booking.Vehicleid,
			&booking.Driver,
			&booking.Startdate,
			&booking.Enddate,
			&booking.Unavailablefrom,
			&booking.Unavailableto,
			&bookingData,
			&booking.Deleted,
			&booking.Vehicle.ID,
			&booking.Vehicle.Type,
			&booking.Vehicle.Namespace,
			pq.Array(&administrators),
			&vehicleData,
			&vehicleMetadata,
		)

		if err != nil {
			return nil, fmt.Errorf("error scanning bookings: %w", err)
		}

		err = json.Unmarshal(bookingData, &booking.Data)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal booking data: %w", err)
		}

		err = json.Unmarshal(vehicleData, &booking.Vehicle.Data)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal vehicle data: %w", err)
		}
		err = json.Unmarshal(vehicleMetadata, &booking.Vehicle.Metadata)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal vehicle metadata: %w", err)
		}

		booking.Vehicle.Administrators = administrators

		bookings = append(bookings, booking)
	}

	return bookings, nil
}

func (psql PostgresqlStorage) DeleteBooking(id string) error {
	query := fmt.Sprintf(`
		DELETE FROM %s
		WHERE id = $1
	`, psql.Tables["booking"])
	_, err := psql.DbConnection.Exec(query, id)
	if err != nil {
		return fmt.Errorf("error deleting booking: %v", err)
	}
	return nil
}

func (psql PostgresqlStorage) Migrate() error {
	ctx := context.Background()
	driver, err := postgres.Open(psql.DbConnection)
	if err != nil {
		return err
	}
	existing, err := driver.InspectRealm(ctx, &schema.InspectRealmOption{Schemas: []string{psql.Schema}})
	if err != nil {
		return err
	}

	var desired schema.Realm

	hcl, err := os.ReadFile("postgresql/schema.hcl")
	if err != nil {
		return err
	}

	err = postgres.EvalHCLBytes(hcl, &desired, nil)
	if err != nil {
		return err
	}

	diff, err := driver.RealmDiff(existing, &desired)
	if err != nil {
		return err
	}

	err = driver.ApplyChanges(ctx, diff)
	if err != nil {
		return err
	}
	return nil
}