const ParameterizedSQL = require('loopback-connector').ParameterizedSQL;
const mergeFilters = require('vn-loopback/util/filter').mergeFilters;

module.exports = Self => {
    Self.remoteMethod('latest', {
        description: 'Returns the lastest campaigns',
        accessType: 'READ',
        accepts: [{
            arg: 'filter',
            type: 'Object',
            description: `Filter defining where, order, offset, and limit - must be a JSON-encoded string`
        }],
        returns: {
            type: ['object'],
            root: true
        },
        http: {
            path: `/latest`,
            verb: 'GET'
        }
    });

    Self.latest = async filter => {
        const conn = Self.dataSource.connector;
        const minDate = new Date();
        minDate.setFullYear(minDate.getFullYear() - 1);

        const where = {dated: {gte: minDate.toJSON().split('T')[0]}};
        filter = mergeFilters(filter, {where});

        const stmt = new ParameterizedSQL(
            `SELECT * FROM (`);
        stmt.merge('SELECT * FROM campaign');
        stmt.merge(conn.makeWhere(filter.where));
        stmt.merge('ORDER BY dated ASC');
        stmt.merge(') sub');
        stmt.merge('GROUP BY code');
        stmt.merge('LIMIT 10000000000000000000');
        stmt.merge(conn.makePagination(filter));

        return conn.executeStmt(stmt);
    };
};