/**
 * Set this up as a midnight cron script
 *
 * mongo habitrpg ./node_modules/moment/moment.js migrations/preen_cron.js
 */

load('./node_modules/lodash/lodash.js');
load('./node_modules/moment/moment.js');

var today = +new Date;

/**
 * Users are allowed to experiment with the site before registering. Every time a new browser visits habitrpg, a new
 * "staged" account is created - and if the user later registers, that staged account is considered a "production" account.
 * This function removes all staged accounts that have been abandoned - either older than a month, or corrupted in
 * some way (lastCron==undefined)
 */
db.users.find({

    // Un-registered users
    "auth.local": {$exists: false},
    "auth.facebook": {$exists: false}

}).forEach(function(user) {
    //if (!user) return;
    var lastCron = user.lastCron;
    if (lastCron && moment(lastCron).isValid()) {
        if (Math.abs(moment(today).diff(lastCron, 'days')) > 3) {
            return db.users.remove({_id: user._id});
        }
    } else {
        return db.users.update({_id: user._id}, {$set: {'lastCron': today}});
    }
});

/**
 * Remove empty parties
 */
db.groups.remove({
    'type': 'party',
    $where: "return this.members.length === 0"
});

/**
 * Preen history for users with > 7 history entries
 * This takes an infinite array of single day entries [day day day day day...], and turns it into a condensed array
 * of averages, condensing more the further back in time we go. Eg, 7 entries each for last 7 days; 4 entries for last
 * 4 weeks; 12 entries for last 12 months; 1 entry per year before that: [day*7 week*4 month*12 year*infinite]
 */
function preenHistory(history) {
    history = _.filter(history, function(h) {return !!h}); // discard nulls (corrupted somehow)
    var newHistory = [];
    function preen(amount, groupBy) {
        var groups, avg, start;
        groups = _(history)
            .groupBy(function(h) { return moment(h.date).format(groupBy) }) // get date groupings to average against
            .sortBy(function(h,k) {return k;}) // sort by date
            .value(); // turn into an array
        amount++; // if we want the last 4 weeks, we're going 4 weeks back excluding this week. so +1 to account for exclusion
        start = (groups.length - amount > 0) ? groups.length - amount : 0;
        groups = groups.slice(start, groups.length - 1)
        _.each(groups, function(group){
            avg = _.reduce(group, function(mem, obj){ return mem + obj.value }, 0) / group.length;
            newHistory.push({date: +moment(group[0].date), value: avg});
        })
    }

    preen(50, 'YYYY'); // last 50 years
    preen(12, 'YYYYMM'); // last 12 months
    preen(4, 'YYYYww'); // last 4 weeks
    newHistory = newHistory.concat(history.slice(-7)); // last 7 days
    return newHistory;
}

var minHistLen = 7;
db.users.find({

    // Registered users with some history
    $or: [
        { 'auth.local': { $exists: true }},
        { 'auth.facebook': { $exists: true }}
    ],
    'history': {$exists: true}

}).forEach(function(user) {
  var update = {$set:{}};

  _.each(user.tasks, function(task) {
      if ( task.history && task.history.length > minHistLen )
        update['$set']['tasks.' + task.id + '.history'] = preenHistory(task.history);
  })

  if (user.history.exp && user.history.exp.length > minHistLen)
    update['$set']['history.exp'] = preenHistory(user.history.exp);
  if (user.history.todos && user.history.todos.length > minHistLen)
    update['$set']['history.todos'] = preenHistory(user.history.todos);

  if (!_.isEmpty(update['$set'])) db.users.update({_id: user._id}, update);
});

/**
 * Don't remove missing user auths anymore. This was previously necessary due to data corruption,
 * revisit if needs be
 */
/*db.sessions.find().forEach(function(sess){
 var uid = JSON.parse(sess.session).userId;
 if (!uid || db.users.count({_id:uid}) === 0) {
 db.sessions.remove({_id:sess._id});
 }
 });*/