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

module.exports = Self => {
    Self.remoteMethodCtx('getTicketsFuture', {
        description: 'Find all tickets that can be moved to the future',
        accessType: 'READ',
        accepts: [
            {
                arg: 'originDated',
                type: 'date',
                description: 'The date in question',
                required: true
            },
            {
                arg: 'futureDated',
                type: 'date',
                description: 'The date to probe',
                required: true
            },
            {
                arg: 'litersMax',
                type: 'number',
                description: 'Maximum volume of tickets to catapult',
                required: true
            },
            {
                arg: 'linesMax',
                type: 'number',
                description: 'Maximum number of lines of tickets to catapult',
                required: true
            },
            {
                arg: 'warehouseFk',
                type: 'number',
                description: 'Warehouse identifier',
                required: true
            },
            {
                arg: 'shipped',
                type: 'date',
                description: 'Origin shipped',
                required: false
            },
            {
                arg: 'tfShipped',
                type: 'date',
                description: 'Destination shipped',
                required: false
            },
            {
                arg: 'ipt',
                type: 'string',
                description: 'Origin Item Packaging Type',
                required: false
            },
            {
                arg: 'tfIpt',
                type: 'string',
                description: 'Destination Item Packaging Type',
                required: false
            },
            {
                arg: 'id',
                type: 'number',
                description: 'Origin id',
                required: false
            },
            {
                arg: 'tfId',
                type: 'number',
                description: 'Destination id',
                required: false
            },
            {
                arg: 'state',
                type: 'string',
                description: 'Origin state',
                required: false
            },
            {
                arg: 'tfState',
                type: 'string',
                description: 'Destination state',
                required: false
            },
            {
                arg: 'problems',
                type: 'boolean',
                description: `Whether to show only tickets with problems`,
                required: false
            },
            {
                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: `/getTicketsFuture`,
            verb: 'GET'
        }
    });

    Self.getTicketsFuture = async (ctx, options) => {
        const args = ctx.args;
        const conn = Self.dataSource.connector;
        const myOptions = {};

        if (typeof options == 'object')
            Object.assign(myOptions, options);

        const where = buildFilter(ctx.args, (param, value) => {
            switch (param) {
                case 'id':
                    return { 'f.id': value };
                case 'tfId':
                    return { 'f.ticketFuture': value };
                case 'shipped':
                    return { 'f.shipped': value };
                case 'tfShipped':
                    return { 'f.tfShipped': value };
                case 'ipt':
                    return { 'f.ipt': value };
                case 'tfIpt':
                    return { 'f.tfIpt': value };
                case 'state':
                    return { 'f.code': { like: `%${value}%` } };
                case 'tfState':
                    return { 'f.tfCode': { like: `%${value}%` } };
            }
        });

        let filter = mergeFilters(ctx.args.filter, { where });
        const stmts = [];
        let stmt;

        stmt = new ParameterizedSQL(
            `CALL vn.ticket_canbePostponed(?,?,?,?,?)`,
            [args.originDated, args.futureDated, args.litersMax, args.linesMax, args.warehouseFk]);

        stmts.push(stmt);

        stmts.push('DROP TEMPORARY TABLE IF EXISTS tmp.sale_getProblems');

        stmt = new ParameterizedSQL(`
            CREATE TEMPORARY TABLE tmp.sale_getProblems
            (INDEX (ticketFk))
            ENGINE = MEMORY
            SELECT f.id ticketFk, f.clientFk, f.warehouseFk, f.shipped
            FROM tmp.filter f
            LEFT JOIN alertLevel al ON al.id = f.alertLevel
            WHERE (al.code = 'FREE' OR f.alertLevel IS NULL)`);
        stmts.push(stmt);

        stmts.push('CALL ticket_getProblems(FALSE)');

        stmt = new ParameterizedSQL(`
            SELECT f.*, tp.*
            FROM tmp.filter f
            LEFT JOIN tmp.ticket_problems tp ON tp.ticketFk = f.id`);

        if (args.problems != undefined && (!args.originDated && !args.futureDated))
            throw new UserError('Choose a date range or days forward');

        let condition;
        let hasProblem;
        let range;
        let hasWhere;
        switch (args.problems) {
            case true:
                condition = `or`;
                hasProblem = true;
                range = { neq: null };
                hasWhere = true;
                break;

            case false:
                condition = `and`;
                hasProblem = null;
                range = null;
                hasWhere = true;
                break;
        }

        const problems = {
            [condition]: [
                { 'tp.isFreezed': hasProblem },
                { 'tp.risk': hasProblem },
                { 'tp.hasTicketRequest': hasProblem },
                { 'tp.itemShortage': range },
                { 'tp.hasComponentLack': hasProblem },
                { 'tp.isTooLittle': hasProblem }
            ]
        };

        if (hasWhere) {
            filter = mergeFilters(filter, { where: problems });
        }

        stmt.merge(conn.makeWhere(filter.where));
        stmt.merge(conn.makeOrderBy(filter.order));
        stmt.merge(conn.makeLimit(filter));

        const ticketsIndex = stmts.push(stmt) - 1;

        stmts.push(
            `DROP TEMPORARY TABLE
                tmp.filter,
                tmp.ticket_problems`);

        const sql = ParameterizedSQL.join(stmts, ';');

        const result = await conn.executeStmt(sql, myOptions);

        return result[ticketsIndex];
    };
};