const ParameterizedSQL = require('loopback-connector').ParameterizedSQL;

module.exports = Self => {
    Self.remoteMethod('getSerial', {
        description: 'Return invoiceIn serial',
        accessType: 'READ',
        accepts: [{
            arg: 'daysAgo',
            type: 'number',
            required: true
        }, {
            arg: 'serial',
            type: 'string'
        }],
        returns: {
            type: 'object',
            root: true
        },
        http: {
            path: '/getSerial',
            verb: 'GET'
        }
    });

    Self.getSerial = async(daysAgo, serial) => {
        const conn = Self.dataSource.connector;
        const stmt = [];

        const issued = Date.vnNew();
        issued.setDate(issued.getDate() - daysAgo);

        stmt.push(new ParameterizedSQL(`
            SELECT i.serial, SUM(IF(i.isBooked, 0,1)) pending, COUNT(*) total
                FROM vn.invoiceIn i
                WHERE i.issued >= ? `, [issued]));

        if (serial)
            stmt.push(new ParameterizedSQL(`AND i.serial LIKE ? `, [serial]));

        stmt.push(`GROUP BY i.serial`);

        const sql = ParameterizedSQL.join(stmt);
        const result = await conn.executeStmt(sql);

        return result;
    };
};