package database

import (
	"database/sql"
	"errors"
)

var ErrStorageAreaDoesNotExist error = errors.New("Storage area does not exist.")

var StorageAreaTypeBinder string = "Binder"
var StorageAreaTypeBox string = "Box"

type StorageArea struct {
	Id          int
	Name        string
	StorageType string
}

func GetAllStorageAreas(db *sql.DB) ([]StorageArea, error) {
	var storageAreas []StorageArea

	query := `SELECT * FROM StorageArea;`
	rows, err := db.Query(query)
	defer rows.Close()
	if err != nil {
		return storageAreas, err
	}

	var area StorageArea
	for rows.Next() {
		err := rows.Scan(&area.Id, &area.Name, &area.StorageType)
		if err != nil {
			return storageAreas, err
		}

		storageAreas = append(storageAreas, area)
	}

	return storageAreas, nil
}

func GetStorageAreaIdByName(db *sql.DB, storageAreaName string) (int, error) {
	var storageAreaId int

	query := `SELECT Id FROM StorageArea WHERE Name = ?;`
	row := db.QueryRow(query, storageAreaName)

	err := row.Scan(&storageAreaId)
	if err == sql.ErrNoRows {
		return storageAreaId, ErrStorageAreaDoesNotExist
	} else if err != nil {
		return storageAreaId, err
	}

	return storageAreaId, nil
}

func GetStorageAreaTypeById(db *sql.DB, storageAreaId int) (string, error) {
	var storageType string

	query := `SELECT StorageType FROM StorageArea WHERE Id = ?;`
	row := db.QueryRow(query, storageAreaId)

	err := row.Scan(&storageType)
	if err != nil {
		return storageType, err
	}

	return storageType, nil
}

func GetNextEmptySlotInBinder(db *sql.DB, storageAreaId int) (int, error) {
	query := `SELECT Id FROM CardLocation WHERE CardPrintingId IS NULL AND StorageAreaId = ? ORDER BY Position ASC LIMIT 1;`

	var emptySlotId int
	err := db.QueryRow(query, storageAreaId).Scan(&emptySlotId)
	if err == sql.ErrNoRows {
		return -1, nil
	} else if err != nil {
		return 0, err
	}

	return emptySlotId, nil
}

func InsertStorageArea(db *sql.DB, storageArea StorageArea) error {
	query := `INSERT INTO StorageArea (Name, StorageType) VALUES (?, ?);`

	insert, err := db.Prepare(query)
	if err != nil {
		return err
	}

	_, err = insert.Exec(storageArea.Name, storageArea.StorageType)
	if err != nil {
		return err
	}

	return nil
}