db.getCollection('communities').aggregate([
    {
        $match: {
            'value.managers': ObjectId('5e6e22147de0fc000ffd24d0'),
            _id: ObjectId('5e812a9a2b21e4000f0e6311'),
        },
    },
    {
        $addFields: {
            manager_requesting: ObjectId('5e6e22147de0fc000ffd24d0'),
        },
    },
    // fetch requesting manager data
    {
        $lookup: {
            from: 'users',
            localField: 'manager_requesting',
            foreignField: '_id',
            as: 'manager',
        },
    },
    { $unwind: '$manager' },
    // fetch ideas for community
    {
        $lookup: {
            from: 'ideas',
            let: { cummunityId: '$_id' },
            pipeline: [
                {
                    $match: {
                        $expr: {
                            $eq: ['$community', '$$cummunityId'],
                        },
                    },
                },
                // fetch views data
                {
                    $lookup: {
                        from: 'user_actions_history',
                        localField: '_id',
                        foreignField: 'meta.ideaId',
                        as: 'views',
                    },
                },
                // fetch idea owner data
                {
                    $lookup: {
                        from: 'users',
                        let: { owner: '$owner' },
                        pipeline: [
                            {
                                $match: {
                                    $expr: {
                                        $eq: ['$_id', '$$owner'],
                                    },
                                },
                            },
                            {
                                $project: {
                                    _id: 0,
                                    fName: 1,
                                    lName: 1,
                                    email: 1,
                                    faculty: 1,
                                    role: 1,
                                    jobTitle: 1,
                                },
                            },
                        ],
                        as: 'idea_owner',
                    },
                },
                { $unwind: '$idea_owner' },
                {
                    $project: {
                        _id: 0,
                        title: 1,
                        description: 1,
                        requesting_manager_name: '$manager.fname',
                        owner_fName: "$idea_owner.fName",
                        owner_lName: "$idea_owner.lName",
                        email: "$idea_owner.email",
                        rank: 1,
                        likes: { $size: "$likes" },
                        views: { $size: "$views" },
                        updatedAt: 1,
                    },
                },
            ],
            as: 'ideasByCommunity',
        },
    },
    { $unwind: "$ideasByCommunity" },
    {
        $group: {
            _id: null,
            //            name: '$value.name',
            //            requesting_manager_name: { $concat: ['$manager.fname', ' ', '$manager.lname'] },
            //            requesting_manager_email: '$manager.email',
            ideasByCommunities: {
                $push: {
                    name: '$value.name',
                    requesting_manager_name: { $concat: ['$manager.fname', ' ', '$manager.lname'] },
                    requesting_manager_email: '$manager.email',
                    title: '$ideasByCommunity.title',
                    description: '$ideasByCommunity.description',
                    owner_fName: "$ideasByCommunity.owner_fName",
                    owner_lName: "$ideasByCommunity.owner_lName",
                    email: "$ideasByCommunity.email",
                    rank: "$ideasByCommunity.rank",
                    likes: "$ideasByCommunity.likes",
                    views: "$ideasByCommunity.views",
                    updatedAt: 1,
                }
            },
            //            ideasByCommunities: '$ideasByCommunity',
        },
    },
]).toArray();