const warehouseIds = [1, 44];

module.exports = Self => {
    Self.remoteMethod('catalog', {
        description: 'Get the catalog',
        accessType: 'READ',
        accepts: [
            {
                arg: 'dated',
                type: 'Date',
                description: 'The available date'
            }, {
                arg: 'typeFk',
                type: 'Number',
                description: 'The item type id'
            }, {
                arg: 'search',
                type: 'String',
                description: 'The search string'
            }, {
                arg: 'order',
                type: 'String',
                description: 'The order string'
            }, {
                arg: 'limit',
                type: 'Number',
                description: 'The maximum number of registers'
            }, {
                arg: 'tagFilter',
                type: ['Object'],
                description: 'The tag filter object'
            }
        ],
        returns: {
            type: ['Object'],
            description: 'The item list',
            root: true,
        },
        http: {
            path: `/catalog`,
            verb: 'GET'
        }
    });

    Self.catalog = async (dated, typeFk, search, order, limit, tagFilter) => {
        let $ = Self.app.models;
        let itemIds;

        let inboundWhere = {
            warehouseFk: {inq: warehouseIds},
            available: {gt: 0},
            dated: {lte: dated},
            and: [
                {or: [
                    {expired: {gt: dated}},
                    {expired: null}
                ]}
            ]
        };

        // Applies base filters

        if (/^[0-9]+$/.test(search)) {
            itemIds = [parseInt(search)];
        } else {
            if (typeFk || search) {
                let where = {};

                if (typeFk)
                    where.typeFk = typeFk;
                if (search)
                    where.longName = {like: `%${search}%`};

                let filter = {
                    fields: ['id'],
                    where
                };

                let items = await Self.find(filter);
                itemIds = items.map(i => i.id);
            }

            let where = Object.assign({}, inboundWhere);
            if (itemIds) where.itemFk = {inq: itemIds};

            let inbounds = await $.Inbound.find({
                fields: ['itemFk'],
                where
            });
            itemIds = toValues(inbounds, 'itemFk');
        }

        // Applies tag filters

        let baseItemIds = itemIds;
        let tagItems = [];
        let tagFilterIds = [];

        if (tagFilter && tagFilter.length) {
            for (let filter of tagFilter) {
                let cond;
                let values = filter.values;

                if (values.length)
                    cond = {value: {inq: values}};
                else if (values.min && values.max)
                    cond = {intValue: {between: [values.min, values.max]}};
                else if (values.min)
                    cond = {intValue: {gte: values.min}};
                else if (values.max)
                    cond = {intValue: {lte: values.max}};

                let where = {
                    itemFk: {inq: itemIds},
                    tagFk: filter.tagFk
                };
                Object.assign(where, cond);

                let itemTags = await $.ItemTag.find({
                    fields: ['itemFk'],
                    where
                });
                tagItems.push(toSet(itemTags, 'itemFk'));
                tagFilterIds.push(filter.tagFk);
            }

            itemIds = intersect(tagItems);
        }

        // Obtains distinct tags and it's distinct values

        let tagValues = await $.ItemTag.find({
            fields: ['tagFk', 'value', 'intValue', 'priority'],
            where: {
                itemFk: {inq: itemIds},
                tagFk: {nin: tagFilterIds}
            },
            order: 'tagFk, value'
        });
        let tagValueMap = toMultiMap(tagValues, 'tagFk');

        for (let i = 0; i < tagItems.length; i++) {
            let tagFk = tagFilter[i].tagFk;
            let itemIds;

            if (tagItems.length > 1) {
                let siblings = tagItems.filter(v => v != tagItems[i]);
                itemIds = intersect(siblings);
            } else
                itemIds = baseItemIds;

            let tagValues = await $.ItemTag.find({
                fields: ['value', 'intValue', 'priority'],
                where: {
                    itemFk: {inq: itemIds},
                    tagFk: tagFk
                },
                order: 'value'
            });

            tagValueMap.set(tagFk, tagValues);
        }

        let tagIds = [...tagValueMap.keys()];
        let tags = await $.Tag.find({
            fields: ['id', 'name', 'isQuantitative', 'unit'],
            where: {
                id: {inq: tagIds}
            }
        });

        for (let tag of tags) {
            let tagValues = tagValueMap.get(tag.id);

            let filter = tagFilter && tagFilter.find(i => i.tagFk == tag.id);
            filter = filter && filter.values;

            let values = toSet(tagValues, 'value');
            if (Array.isArray(filter))
                values = new Set([...filter, ...values]);

            if (tag.isQuantitative) {
                let intValues = toValues(tagValues, 'intValue');

                if (filter) {
                    if (filter.min) intValues.push(filter.min);
                    if (filter.max) intValues.push(filter.max);
                }

                let min = Math.min(...intValues);
                let max = Math.max(...intValues);
                let dif = max - min;
                let digits = new String(dif).length;
                let step = Math.pow(10, digits - 1);
                if (digits > 1 && step * 5 > dif) step /= 10;

                Object.assign(tag, {
                    step,
                    min: Math.floor(min / step) * step,
                    max: Math.ceil(max / step) * step
                });
            }

            Object.assign(tag, {
                values: [...values],
                filter
            });
        }

        // Obtains items data
/*
        let inbounds = await $.Inbound.find({
            fields: ['itemFk', 'available', 'dated'],
            include: 'item',
            where: Object.assign(
                {itemFk: {inq: itemIds}},
                inboundWhere
            )
        });
*/
        let items = await Self.find({
            where: {id: {inq: itemIds}},
            include: [
                {
                    relation: 'tags',
                    scope: {include: 'tag'}
                }, {
                    relation: 'inbounds',
                    scope: {
                        fields: ['available', 'dated'],
                        where: inboundWhere
                    }
                }
            ],
            limit: limit,
            order: order
        });

        return {items, tags};
    };

    function toMap(objects, key) {
        let map = new Map();
        for (let object of objects)
            map.set(object[key], object);
        return map;
    }

    function toMultiMap(objects, key) {
        let map = new Map();
        for (let object of objects) {
            let value = map.get(object[key]);
            if (!value) map.set(object[key], value = []);
            value.push(object);
        }
        return map;
    }

    function toSet(objects, key) {
        let set = new Set();
        for (let object of objects)
            set.add(object[key]);
        return set;
    }

    function toValues(objects, key) {
        return [...toSet(objects, key)];
    }

    function intersect(sets) {
        if (!sets.length) return [];
        let array = [];
        let mySets = sets.slice(0);
        let firstSet = mySets.shift();

        for (let value of firstSet) {
            let isOnAll = true;

            for (let set of mySets)
            if (!set.has(value)) {
                isOnAll = false;
                break;
            }

            if (isOnAll)
                array.push(value);
        }

        return array;
    }
};