/**
 *  store - abstract class
 *
 *  @author Björn Hase <me@herr-hase.wtf>
 *  @license http://opensource.org/licenses/MIT The MIT License
 *  @link https://gitea.node001.net/HerrHase/urban-filehub.git
 *
 */

class Store {

    /**
     *
     *
     * @param {tableName}
     *
     */
    constructor(db, tableName) {
        this._db = db
        this._tableName = tableName
    }

    /**
     *  create row 
     *
     */
    findOneById(id) {
        return this._db
            .prepare('SELECT * FROM ' + this._tableName + ' WHERE id = ?')
            .get(id)
    }

    /**
     *  create row 
     *
     */
    remove(id) {
        return this._db
            .prepare('DELETE FROM ' + this._tableName + ' WHERE id = ?')
            .run(id)
    }

    /**
     *
     *
     */
    update(id, data) {
        return this._db
            .prepare('UPDATE ' + this._tableName + ' SET ' + this._prepareUpdateBinding(data) + ' WHERE id = ?')
            .run(data, id)
    }

    /**
     *
     *
     */
    create(data) {
        const result = this._db
            .prepare('INSERT INTO ' + this._tableName + ' (' + Object.keys(data).join(', ') + ') VALUES (' + this._prepareInsertBinding(data) + ')')
            .run(data)

        if (!result.lastInsertRowid) {
            throw new Error('Store / missing id after created data')
        }

        return result.lastInsertRowid
    }

    /**
     *  run through object and add key to string for
     *  binding parameters for insert
     *
     *  @param  {object} data
     *  @return {string}
     */
    _prepareInsertBinding(data) {
        let result = ''
        let length = Object.keys(data).length
        let index = 0

        for (const key in data) {
            result += '@' + key

            if (index++ < (length - 1)) {
                result += ', '
            }
        }

        return result
    }

    /**
     *  run through object and add key to string for
     *  binding parameters for update
     *
     *  @param  {object} data
     *  @return {string}
     */
    _prepareUpdateBinding(data) {
        let result = ''
        let length = Object.keys(data).length
        let index = 0

        for (const key in data) {
            result += key + ' = @' + key

            if (index++ < (length - 1)) {
                result += ', '
            }
        }

        return result
    }
}

export default Store