define([
  'angular',
  'lodash',
  'jquery',
  'app/core/config',
  'app/core/utils/datemath',
  './directives',
  './query_ctrl',
  './func_editor',
  './add_graphite_func',
],
function (angular, _, $, config, dateMath) {
  'use strict';

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

  module.factory('GraphiteDatasource', function($q, backendSrv, templateSrv) {

    function GraphiteDatasource(datasource) {
      this.basicAuth = datasource.basicAuth;
      this.url = datasource.url;
      this.name = datasource.name;
      this.cacheTimeout = datasource.cacheTimeout;
      this.withCredentials = datasource.withCredentials;
      this.render_method = datasource.render_method || 'POST';
    }

    GraphiteDatasource.prototype.query = function(options) {
      try {
        var graphOptions = {
          from: this.translateTime(options.rangeRaw.from, false),
          until: this.translateTime(options.rangeRaw.to, true),
          targets: options.targets,
          format: options.format,
          cacheTimeout: options.cacheTimeout || this.cacheTimeout,
          maxDataPoints: options.maxDataPoints,
        };

        var params = this.buildGraphiteParams(graphOptions, options.scopedVars);
        if (params.length === 0) {
          return $q.when([]);
        }

        if (options.format === 'png') {
          return $q.when(this.url + '/render' + '?' + params.join('&'));
        }

        var httpOptions = { method: this.render_method, url: '/render' };

        if (httpOptions.method === 'GET') {
          httpOptions.url = httpOptions.url + '?' + params.join('&');
        }
        else {
          httpOptions.data = params.join('&');
          httpOptions.headers = { 'Content-Type': 'application/x-www-form-urlencoded' };
        }

        return this.doGraphiteRequest(httpOptions).then(this.convertDataPointsToMs);
      }
      catch(err) {
        return $q.reject(err);
      }
    };

    GraphiteDatasource.prototype.convertDataPointsToMs = function(result) {
      if (!result || !result.data) { return []; }
      for (var i = 0; i < result.data.length; i++) {
        var series = result.data[i];
        for (var y = 0; y < series.datapoints.length; y++) {
          series.datapoints[y][1] *= 1000;
        }
      }
      return result;
    };

    GraphiteDatasource.prototype.annotationQuery = function(options) {
      // Graphite metric as annotation
      if (options.annotation.target) {
        var target = templateSrv.replace(options.annotation.target);
        var graphiteQuery = {
          rangeRaw: options.rangeRaw,
          targets: [{ target: target }],
          format: 'json',
          maxDataPoints: 100
        };

        return this.query(graphiteQuery)
          .then(function(result) {
            var list = [];

            for (var i = 0; i < result.data.length; i++) {
              var target = result.data[i];

              for (var y = 0; y < target.datapoints.length; y++) {
                var datapoint = target.datapoints[y];
                if (!datapoint[0]) { continue; }

                list.push({
                  annotation: options.annotation,
                  time: datapoint[1],
                  title: target.target
                });
              }
            }

            return list;
          });
      }
      // Graphite event as annotation
      else {
        var tags = templateSrv.replace(options.annotation.tags);
        return this.events({range: options.rangeRaw, tags: tags})
          .then(function(results) {
            var list = [];
            for (var i = 0; i < results.data.length; i++) {
              var e = results.data[i];

              list.push({
                annotation: options.annotation,
                time: e.when * 1000,
                title: e.what,
                tags: e.tags,
                text: e.data
              });
            }
            return list;
          });
      }
    };

    GraphiteDatasource.prototype.events = function(options) {
      try {
        var tags = '';
        if (options.tags) {
          tags = '&tags=' + options.tags;
        }

        return this.doGraphiteRequest({
          method: 'GET',
          url: '/events/get_data?from=' + this.translateTime(options.range.from, false) +
            '&until=' + this.translateTime(options.range.to, true) + tags,
        });
      }
      catch(err) {
        return $q.reject(err);
      }
    };

    GraphiteDatasource.prototype.translateTime = function(date, roundUp) {
      if (_.isString(date)) {
        if (date === 'now') {
          return 'now';
        }
        else if (date.indexOf('now-') >= 0 && date.indexOf('/') === -1) {
          date = date.substring(3);
          date = date.replace('m', 'min');
          date = date.replace('M', 'mon');
          return date;
        }
        date = dateMath.parse(date, roundUp);
      }

      // graphite' s from filter is exclusive
      // here we step back one minute in order
      // to guarantee that we get all the data that
      // exists for the specified range
      if (roundUp) {
        if (date.get('s')) {
          date.add(1, 'm');
        }
      }
      else if (roundUp === false) {
        if (date.get('s')) {
          date.subtract(1, 'm');
        }
      }

      return date.unix();
    };

    GraphiteDatasource.prototype.metricFindQuery = function(query) {
      var interpolated;
      try {
        interpolated = encodeURIComponent(templateSrv.replace(query));
      }
      catch(err) {
        return $q.reject(err);
      }

      return this.doGraphiteRequest({method: 'GET', url: '/metrics/find/?query=' + interpolated })
      .then(function(results) {
        return _.map(results.data, function(metric) {
          return {
            text: metric.text,
            expandable: metric.expandable ? true : false
          };
        });
      });
    };

    GraphiteDatasource.prototype.testDatasource = function() {
      return this.metricFindQuery('*').then(function () {
        return { status: "success", message: "Data source is working", title: "Success" };
      });
    };

    GraphiteDatasource.prototype.listDashboards = function(query) {
      return this.doGraphiteRequest({ method: 'GET',  url: '/dashboard/find/', params: {query: query || ''} })
      .then(function(results) {
        return results.data.dashboards;
      });
    };

    GraphiteDatasource.prototype.loadDashboard = function(dashName) {
      return this.doGraphiteRequest({method: 'GET', url: '/dashboard/load/' + encodeURIComponent(dashName) });
    };

    GraphiteDatasource.prototype.doGraphiteRequest = function(options) {
      if (this.basicAuth || this.withCredentials) {
        options.withCredentials = true;
      }
      if (this.basicAuth) {
        options.headers = options.headers || {};
        options.headers.Authorization = this.basicAuth;
      }

      options.url = this.url + options.url;
      options.inspect = { type: 'graphite' };

      return backendSrv.datasourceRequest(options);
    };

    GraphiteDatasource.prototype._seriesRefLetters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';

    GraphiteDatasource.prototype.buildGraphiteParams = function(options, scopedVars) {
      var graphite_options = ['from', 'until', 'rawData', 'format', 'maxDataPoints', 'cacheTimeout'];
      var clean_options = [], targets = {};
      var target, targetValue, i;
      var regex = /\#([A-Z])/g;
      var intervalFormatFixRegex = /'(\d+)m'/gi;
      var hasTargets = false;

      if (options.format !== 'png') {
        options['format'] = 'json';
      }

      function fixIntervalFormat(match) {
        return match.replace('m', 'min').replace('M', 'mon');
      }

      for (i = 0; i < options.targets.length; i++) {
        target = options.targets[i];
        if (!target.target) {
          continue;
        }

        if (!target.refId) {
          target.refId = this._seriesRefLetters[i];
        }

        targetValue = templateSrv.replace(target.target, scopedVars);
        targetValue = targetValue.replace(intervalFormatFixRegex, fixIntervalFormat);
        targets[target.refId] = targetValue;
      }

      function nestedSeriesRegexReplacer(match, g1) {
        return targets[g1];
      }

      for (i = 0; i < options.targets.length; i++) {
        target = options.targets[i];
        if (!target.target) {
          continue;
        }

        targetValue = targets[target.refId];
        targetValue = targetValue.replace(regex, nestedSeriesRegexReplacer);
        targets[target.refId] = targetValue;

        if (!target.hide) {
          hasTargets = true;
          clean_options.push("target=" + encodeURIComponent(targetValue));
        }
      }

      _.each(options, function (value, key) {
        if ($.inArray(key, graphite_options) === -1) { return; }
        if (value) {
          clean_options.push(key + "=" + encodeURIComponent(value));
        }
      });

      if (!hasTargets) {
        return [];
      }

      return clean_options;
    };

    return GraphiteDatasource;

  });

});
