/**
 * FILE:  api/hooks/reindex-db.js
 *
 * Created by mcrowe on 1/28/15.
 *
 * Insures indices recreated if needed, and allows complex indicies to be specified in the model as well.  Example:
 *
module.exports = {
    schema                     : true,
    version                    : "1.3",
    attributes: {
        ...
        nextCheckDateMax:            { type: 'DATE', index: true },
        currentSequenceNumber:       { type: 'INTEGER' },
        enabled:                     { type: 'BOOLEAN',  defaultsTo: true }
    },
    compoundIndices: {
        ci_1: { nextCheckDateMax: 1, currentSequenceNumber: 1 }
    }
}

 */

var _ = require('lodash');

function ensureIndexCreated(model, collection) {
    var promises = [];
    _.each(model.attributes, function(params, index) {
        if ( _.has(params,'index') ) {
            collection.ensureIndex(index, {background: true}, function(err) {
                if ( err ) {
                    console.log('Error re-indexing collection', err);
                }
            });
        }
    });
    _.each(model.compoundIndices, function(index) {
        collection.ensureIndex(index, {background: true}, function(err) {
            if ( err ) {
                console.log('Error re-indexing collection', err);
            }
        });
    });
    return [];
}

module.exports = function hook(sails) {
    return {
        /**
         * Private hook method to do actual database data operations.
         *
         * @param   {Function}  next    Callback function to call after all is done
         */
        indexDatabase: function indexDatabase(next) {
            _.each(sails.models, function(model) {
                model.native(function(err, collection) { ensureIndexCreated(model, collection); });
            });
            console.log("Indices rebuild");
            next();
        },

        /**
         * Method that runs automatically when the hook initializes itself.
         *
         * @param   {Function}  next    Callback function to call after all is done
         */
        initialize: function initialize(next) {
            var hook = this;

            // Wait for sails orm hook to be loaded
            sails.after('hook:orm:loaded', function onAfter() {
                hook.indexDatabase(next);
            });
        }
    }
};