// PROTOCOL SPECIFICATION
// -----------------------
// /users/count - returns the number of users and how many of them are using VoiceOver
// /users/vib - returns objects representing who are using VoiceOver
// /users/sighted - returns objects representing who are not using VoiceOver

var express = require('express');
var router = express.Router();

var debug = require('debug')('Icarus:server');

var mongoClient = require('mongodb').MongoClient;

var assert = assert = require('assert');

// Connection URL
var mongoUrl = 'mongodb://readOnly:readOnly@localhost:27017/icarus';

//Connect to the server and intialise the pool
var icarusDb;
mongoClient.connect(mongoUrl, function(err, db) {

    assert.equal(null, err, err);
    debug("Connected to MongoDB database: "+db.databaseName);

    icarusDb = db;

});

/* GET root . */
router.get('/', function(req, res, next) {

    res.sendStatus(200);

});

router.get('/users/count', function(req, res, next) {

    var collection = icarusDb.collection('resources');

    var cursor = collection.aggregate(

        // Pipeline
        [
            // Stage 1
            {
                $match: {
                    "appdata.appname":"Invisible Puzzle",
                    "debug":false
                }
            },

            // Stage 2
            {
                $group: {
                    "_id": "$appdata.uuid",
                    "docs": {$sum: 1},
                    "voiceover": {$sum : {$cond: [{$eq:["$appdata.voiceover", true]},1,0]}}
                }
            },

            // Stage 3
            {
                $project: {

                    "docs": 1,
                    "vo_ratio": {$divide:["$voiceover","$docs"]}

                }
            },

            // Stage 4
            {
                $group: {

                    "_id": 1,
                    "users": {$sum: 1},
                    "vib": {$sum : {$cond: [{$gt:["$vo_ratio", 0]},1,0]}}

                }
            },

            // Stage 5
            {

                $project: {

                    "_id": 0,
                    "users": 1,
                    "vib": 1

                }

            }
        ]

    )

    return_cursor(cursor, req, res, next);

});

router.get('/users/vib', function(req, res, next) {

    var cursor = user_ids_cursor(true);
    return_cursor(cursor, req, res, next);

});

router.get('/users/sighted', function(req, res, next) {

    var cursor = user_ids_cursor(false);
    return_cursor(cursor, req, res, next);

});

function user_ids_cursor(vib){

    var filter_condition = {$eq: 0};

    if(vib==true){

        filter_condition  = {$gt: 0}

    }

    var collection = icarusDb.collection('resources');

    return collection.aggregate(

        // Pipeline
        [
            // Stage 1
            {
                $match: {
                    "appdata.appname":"Invisible Puzzle",
                    "debug":false
                }
            },

            // Stage 2
            {
                $group: {
                    "_id": "$appdata.uuid",
                    "docs": {$sum: 1},
                    "voiceover": {$sum : {$cond: [{$eq:["$appdata.voiceover", true]},1,0]}},
                    "levels" : {
                        "$addToSet" : "$userdata.level.id"
                    },
                    "sonifications" : {
                        "$addToSet" : "$userdata.sonification"
                    }
                }

            },

            // Stage 3
            {
                $project: {

                    "docs": 1,
                    "vo_ratio": {$divide:["$voiceover","$docs"]},
                    "levels": 1,
                    "sonification": 1

                }
            },

            // Stage 4
            {
                $match: {

                    "vo_ratio": filter_condition

                }
            }

        ]

    )

}

router.get('/explorations/hp', function(req, res, next) {

    var collection = icarusDb.collection('resources');

    var cursor = collection.aggregate(

        // Pipeline
        [
            // Stage 1
            {
                $match: {
                    "appdata.appname" : "Invisible Puzzle",
                    "userdata.event" : "exploration",
                    "debug" : false
                }
            },

            // Stage 2
            {
                $group: {
                    "_id" : 1,
                    "explorations" : {
                        "$sum" : 1
                    },
                    "with_hp" : {
                        "$sum" : {
                            "$cond" : [
                                {
                                    "$eq" : [
                                        "$userdata.headphones",
                                        true
                                    ]
                                },
                                1,
                                0
                            ]
                        }
                    }
                }
            }

        ]

    );

    return_cursor(cursor, req, res, next);

});

router.get('/explorations/hpbylevel', function(req, res, next) {

    var collection = icarusDb.collection('resources');

    var cursor = collection.aggregate(

        // Pipeline
        [
            // Stage 1
            {
                $match: {
                    "appdata.appname" : "Invisible Puzzle",
                    "userdata.event" : "exploration",
                    "debug" : false
                }
            },

            // Stage 2
            {
                $group: {
                    "_id" : "$userdata.level.id",
                    "explorations" : {
                        "$sum" : 1
                    },
                    "with_hp" : {
                        "$sum" : {
                            "$cond" : [
                                {
                                    "$eq" : [
                                        "$userdata.headphones",
                                        true
                                    ]
                                },
                                1,
                                0
                            ]
                        }
                    }
                }
            },

            // Stage 3
            {
                $project: {
                    "_id": 1,
                    "explorations": 1,
                    "hp_ratio": {$divide:["$with_hp","$explorations"]}
                }
            },

            // Stage 4
            {
                $sort: {
                    "_id": 1
                }
            }

        ]

    );


    return_cursor(cursor, req, res, next);

});

function return_cursor(cursor, req, res, next){

    cursor.toArray(function(err, result) {

        if(err!=null){

            debug(err);
            next(err);

        }else{

            if(result==undefined){

                res.sendStatus(404);

            }else{

                res.send(200,result);

            }

        }

    });

}

module.exports = router;