define([
	'angular',
	'lodash',
	'config',
	'kbn',
	'moment'
], function (angular, _, config, kbn, moment) {
	'use strict';

	var module = angular.module('grafana.services');

	module.service('timeSrv', function ($rootScope, $timeout, $routeParams, timer) {
		var self = this;

		this.init = function (dashboard) {
			timer.cancel_all();

			this.dashboard = dashboard;
			this.time = dashboard.time;

			this._initTimeFromUrl();

			if (this.dashboard.refresh) {
				this.set_interval(this.dashboard.refresh);
			}
		};

		this._parseUrlParam = function (value) {
			if (value.indexOf('now') !== -1) {
				return value;
			}
			if (value.length === 8) {
				return moment.utc(value, 'YYYYMMDD').toDate();
			}
			if (value.length === 15) {
				return moment.utc(value, 'YYYYMMDDTHHmmss').toDate();
			}
			var epoch = parseInt(value);
			if (!_.isNaN(epoch)) {
				return new Date(epoch);
			}

			return null;
		};

		this._initTimeFromUrl = function () {
			if ($routeParams.from) {
				this.time.from = this._parseUrlParam($routeParams.from) || this.time.from;
			}
			if ($routeParams.to) {
				this.time.to = this._parseUrlParam($routeParams.to) || this.time.to;
			}
		};

		this.set_interval = function (interval) {
			this.dashboard.refresh = interval;
			if (interval) {
				var _i = kbn.interval_to_ms(interval);
				this.start_scheduled_refresh(_i);
			} else {
				this.cancel_scheduled_refresh();
			}
		};

		this.refreshDashboard = function () {
			$rootScope.$broadcast('refresh');
		};

		this.start_scheduled_refresh = function (after_ms) {
			self.cancel_scheduled_refresh();
			self.refresh_timer = timer.register($timeout(function () {
				self.start_scheduled_refresh(after_ms);
				self.refreshDashboard();
			}, after_ms));
		};

		this.cancel_scheduled_refresh = function () {
			timer.cancel(this.refresh_timer);
		};

		this.setTime = function (time) {
			_.extend(this.time, time);

			// disable refresh if we have an absolute time
			if (time.to !== 'now') {
				this.old_refresh = this.dashboard.refresh;
				this.set_interval(false);
			}
			else if (this.old_refresh && this.old_refresh !== this.dashboard.refresh) {
				this.set_interval(this.old_refresh);
				this.old_refresh = null;
			}

			$rootScope.appEvent('time-range-changed', this.time);
			$timeout(this.refreshDashboard, 0);
		};

		this.timeRangeForUrl = function () {
			var range = this.timeRange(false);
			if (_.isString(range.to) && range.to.indexOf('now')) {
				range = this.timeRange();
			}

			if (_.isDate(range.from)) {
				range.from = range.from.getTime();
			}
			if (_.isDate(range.to)) {
				range.to = range.to.getTime();
			}

			return range;
		};

		this.timeRange = function (parse) {
			var _t = this.time;
			if (_.isUndefined(_t) || _.isUndefined(_t.from)) {
				return false;
			}
			if (parse === false) {
				return {
					from: _t.from,
					to: _t.to
				};
			} else {
				var _from = _t.from;
				var _to = _t.to || new Date();

				return {
					from: kbn.parseDate(_from),
					to: kbn.parseDate(_to)
				};
			}
		};

	});

});
