const Schmervice = require('@hapipal/schmervice')

module.exports = class MembershipService extends Schmervice.Service {
    constructor(...args) {
        super(...args)
    }

    /**
     * Internal method to get list of grouping_ids for this user
     * @param {number} profileId
     * @returns {Array} List of all grouping_ids for user
     */
    async _getGroupingIdsForProfileId(profileId) {
        const { Membership } = this.server.models()

        /** Grab every Membership associated with this id */
        const allMemberships = await Membership.query().where({
            profile_id: profileId,
        })
        /** Copy a list of the just the Grouping ids */
        const groupingIdsToGrab = allMemberships.map(
            membership => membership.grouping_id,
        )

        /** Uncomment to dedupe the list just in case */
        return [...new Set(groupingIdsToGrab)]
    }

    /**
     * Internal method to create a new grouping
     * @param {object} groupingToTry from payload data
     * @param {*} txn
     * @returns {Grouping} created db record
     */
    async _createGrouping(groupingToTry, txn) {
        const { Grouping } = this.server.models()
        const groupingInfo = {
            grouping_name: groupingToTry.grouping_name,
            grouping_type: groupingToTry.grouping_type,
        }
        return await Grouping.query(txn).insert(groupingInfo)
    }
    /**
     * Tries to grab a grouping_id from payload data
     * or returns grouping_id from a newly created record
     * @param {object} groupingToTry from payload data
     * @returns {number} grouping_id from payload or created record
     */
    async findOrCreateGroupingFromPayload(groupingToTry) {
        let idToReturn = groupingToTry.grouping_id
        if (!idToReturn) {
            /** ?: For some reason this returns the key id */
            const grouping = await this._createGrouping(groupingToTry)
            idToReturn = grouping.id
        }
        return idToReturn
    }

    /**
     * Get a list of groupings for user
     * @param {number} profileId
     * @returns {Array}
     */
    async findGroupingsByProfileId(profileId, type) {
        const { Grouping } = this.server.models()
        const dedupedGroupings = await this._getGroupingIdsForProfileId(
            profileId,
            type,
        )
        /** Grab just the Groupings this id has a Membership for */
        return await Grouping.query()
            .whereIn('grouping_id', dedupedGroupings)
            .withGraphFetched('profiles')
    }

    async _groupingIdsInCommon(profileId, targetId) {
        const uids = await this._getGroupingIdsForProfileId(profileId)
        const tids = await this._getGroupingIdsForProfileId(targetId)
        const common = []
        for (let i in uids) {
            if (tids.indexOf(uids[i]) !== -1) common.push(uids[i])
        }
        return common.sort((x, y) => x - y)
    }

    async _patchMembership(memberships, profileId, patch) {
        const { Membership } = this.server.models()

        /** Set membership as active only if the user initiates it */
        for (let membershipInfo of memberships) {
            await Membership.query()
                .where('membership_id', membershipInfo.membership_id)
                .where('profile_id', profileId)
                .patch(patch)
        }
    }

    /**
     * Check for grouping membership then add membership record and set to active
     * or create a new grouping and add membership record for user and membership record for target
     * @param {number} profileId
     * @param {number} targetId
     * @param {object} groupingToWrite
     * @param {string} role
     * @returns
     */
    async joinGrouping(profileId, targetId, groupingToWrite, role, txn) {
        const { Membership } = this.server.models()

        /** If both people have groups in common */
        const matchingGroupingIds = await this._groupingIdsInCommon(
            profileId,
            targetId,
        )

        if (matchingGroupingIds.length) {
            /** Grab all memberships associated with groupingIds */
            const memberships = await Membership.query().whereIn(
                'grouping_id',
                matchingGroupingIds,
            )

            /** Set membership as active only if the user initiates it */
            await this._patchMembership(memberships, profileId, {
                is_active: true,
            })

            /** Make a new query to get updated information */
            return await Membership.query().whereIn(
                'grouping_id',
                matchingGroupingIds,
            )
        } else {
            /**
             * If both have NO grouping in common, create a membership
             * for both and add to a new grouping but
             * set membership as inactive for target
             * */

            /** Check if the grouping exists and if NOT create it */
            const groupingId = await this.findOrCreateGroupingFromPayload(
                groupingToWrite,
            )
            const membershipDetailsInCommon = {
                grouping_id: groupingId,
                membership_type: role,
                can_edit: false,
            }

            const userMembership = await Membership.query(txn).insert({
                profile_id: profileId,
                ...membershipDetailsInCommon,
                is_active: true,
            })

            const targetMembership = await Membership.query(txn).insert({
                profile_id: targetId,
                ...membershipDetailsInCommon,
                is_active: false,
            })

            return [userMembership, targetMembership]
        }
    }

    /**
     * Remove membership record based on grouping_id
     * @param {number} profileId
     * @param {number} groupingId
     * @returns
     */
    async leaveGrouping(profileId, groupingId) {
        const { Membership } = this.server.models()

        const dedupedGroupings = await this._getGroupingIdsForProfileId(
            profileId,
        )

        /** Do NOTHING if NOT in Grouping */
        if (!dedupedGroupings.includes(groupingId)) return

        return await Membership.query()
            .delete()
            .where('grouping_id', groupingId)
    }
}