var db = require("../dbconnection");
var mysql = require("mysql");

var parkingLog = {

    /**
     * Creates a new parkingLog.
     */
    addParkingLog: function (id, currentParked, logDate, callback) {
        this.newHistoricParkCount(id, currentParked, () => {
            this.insertParkingLog();
        })
    },

    /**
     * Checks the totalParked value of the latest dated log, to check if it should increment
     */
    newHistoricParkCount: function(id, currentParked, callback) {
        this.getAParkingLotsLatestParkingLog(id, (err, rows) => {
            let old;
            let increment = 0;
            if (err) {
                old = parseRowDataIntoSingleEntity(rows);
            }
            else {
                old = parseRowDataIntoSingleEntity(rows);
            }
            if (currentParked > old.currentParked) {
                increment = currentParked - old.currentParked;
            }
            let historicParkCount = old.historicParkCount + increment;
            console.log("historicParkCount " + historicParkCount);
            console.log("Callback(historicParkCount)"); // prints a valid number
            callback(id, currentParked, historicParkCount);
        });
    }

    /**
     * Insert parkingLog, do not call this method directly.
     */
    insertParkingLog: function(id, currentParked, historicParkCount, callback) {
        console.log("id: " + id); // prints undefined
        console.log("currentParked: " + currentParked); // prints undefined
        console.log("historicParkCount: " + historicParkCount); // prints undefined
        if (typeof logDate === "undefined") {
            //    console.log("inside if");
            var query = "INSERT INTO ??(??,??) VALUES (?,?,?)";
            var table = ["parkingLog", "currentParked", "parkingLot_id", "historicParkCount",
                currentParked, id, historicParkCount];
        }
        else {
            //     console.log("inside else");
            var query = "INSERT INTO ??(??,??,??) VALUES (?,?,?)";
            var table = ["parkingLog", "currentParked", "parkingLot_id", "logDate", "historicParkCount",
                currentParked, id, logDate, historicParkCount];
        }
        query = mysql.format(query, table);
        db.query(query, callback);
    },

    /**
     * Returns the latest parkingLog based on logDate.
     */
    getAParkingLotsLatestParkingLog: function(parkingLot_id, callback) {

        db.query("SELECT * FROM parkingLog WHERE parkingLot_id=? ORDER BY logDate DESC LIMIT 1",
            parkingLot_id, callback);
    }
};

module.exports = parkingLog;