export default class Recorder {

    constructor(db) {
        this.db = db;
        this.lines = {};
        this.vehModified = {};
    }

    async start() {
        await this._createTables();
        await this._loadLast();
    }

    async _createTables() {
        if (!this.db)
            return;

        if (!await this.db.schema.hasTable('veh_lines')) {
            await this.db.schema.createTable('veh_lines', t => {
                t.timestamp('date', { useTz: false }).defaultTo(this.db.fn.now());
                t.smallint('vehicle').notNullable();
                t.string('line', 32).nullable(); // 4, 9....
            });
        }

        if (!await this.db.schema.hasTable('veh_pos')) {
            await this.db.schema.createTable('veh_pos', t => {
                t.timestamp('date', { useTz: false }).defaultTo(this.db.fn.now());
                t.float('lat').nullable();
                t.float('long').nullable();
                t.smallint('vehicle').notNullable();
                t.smallint('line').nullable();
            });
        }
    }

    async _loadLast() {
        const lineData = await this.db('veh_lines')
            .distinctOn('vehicle')
            .orderBy([
                { column: 'vehicle', order: 'asc' },
                { column: 'date', order: 'desc' },
            ]);

        for (let row of lineData) {
            this.lines[row.vehicle.toString()] = parseInt(row.line) || null;
        }

        const vehData = await this.db
            .select('vehicle', 'date')
            .from('veh_pos')
            .distinctOn('vehicle')
            .orderBy([
                { column: 'vehicle', order: 'asc' },
                { column: 'date', order: 'desc' },
            ]);

        for (let row of vehData) {
            this.vehModified[row.vehicle.toString()] = new Date(row.date);
        }
    }

    async putVehicle(veh) {
        // TODO: Add filters for data integrity (vehicleNumber === null
        let lineNumber = parseInt(veh.lineNumber) || null;
        if (this.lines[veh.vehicleNumber.toString()] !== lineNumber) {
            await this.db('veh_lines').insert({
                vehicle: veh.vehicleNumber,
                line: veh.lineNumber,
                date: veh.lastModified,
            });
            this.lines[veh.vehicleNumber.toString()] = lineNumber;
        }

        if (this.vehModified[veh.vehicleNumber]?.getTime() !== veh.lastModified.getTime()) {
            // console.log('for', veh.vehicleNumber, this.vehModified[veh.vehicleNumber], ' vs. from open', veh.lastModified)
            await this.db('veh_pos').insert({
                vehicle: veh.vehicleNumber,
                line: veh.lineNumber,
                date: veh.lastModified,
                lat: veh.gpsLatitude,
                long: veh.gpsLongitude,
            });
            this.vehModified[veh.vehicleNumber] = veh.lastModified;
        }

    }

    async getVehicleTrace(vehId, count) {
        return await this.db
            .select('date', 'lat', 'long')
            .from('veh_pos')
            .where({
                vehicle: parseInt(vehId),
            })
            // .andWhere('date', '<', '2022-06-24T14:07:00')
            .orderBy('date', 'desc')
            .limit(count);
    }

    async getLineTrace(line, count) {
        return await this.db
            .select('date', 'lat', 'long')
            .from('veh_pos')
            .where({
                line: parseInt(line),
            })
            .orderBy('date', 'desc')
            .limit(count);
    }

    async getSimpleLineTrace(line, count) {
        return await this.db
            .select('lat', 'long')
            .from('veh_pos')
            .where({
                line: parseInt(line),
            })
            .limit(count);
    }

}