Show trends on some dashboard numbers

app/assets/javascripts/admin/models/report.js

@@ -1,7 +1,69 @@
 Discourse.Report = Discourse.Model.extend({
   reportUrl: function() {
     return("/admin/reports/" + this.get('type'));
-  }.property('type')
+  }.property('type'),
+
+  valueAt: function(numDaysAgo) {
+    if (this.data) {
+      var wantedDate = Date.create(numDaysAgo + ' days ago', 'en').format('{yyyy}-{MM}-{dd}');
+      var item = this.data.find( function(d, i, arr) { return d.x === wantedDate; } );
+      if (item) {
+        return item.y;
+      }
+    }
+    return 0;
+  },
+
+  sumDays: function(startDaysAgo, endDaysAgo) {
+    if (this.data) {
+      var earliestDate = Date.create(endDaysAgo + ' days ago', 'en');
+      var latestDate = Date.create(startDaysAgo + ' days ago', 'en');
+      var d, sum = 0;
+      this.data.each(function(datum){
+        d = Date.create(datum.x);
+        if(d >= earliestDate && d <= latestDate) {
+          sum += datum.y;
+        }
+      });
+      return sum;
+    }
+  },
+
+  yesterdayTrend: function() {
+    var yesterdayVal = this.valueAt(1);
+    var twoDaysAgoVal = this.valueAt(2);
+    if ( yesterdayVal > twoDaysAgoVal ) {
+      return 'trending-up';
+    } else if ( yesterdayVal < twoDaysAgoVal ) {
+      return 'trending-down';
+    } else {
+      return 'no-change';
+    }
+  }.property('data'),
+
+  sevenDayTrend: function() {
+    var currentPeriod = this.sumDays(1,7);
+    var prevPeriod = this.sumDays(8,14);
+    if ( currentPeriod > prevPeriod ) {
+      return 'trending-up';
+    } else if ( currentPeriod < prevPeriod ) {
+      return 'trending-down';
+    } else {
+      return 'no-change';
+    }
+  }.property('data'),
+
+  thirtyDayTrend: function() {
+    if( this.get('prev30Days') ) {
+      var currentPeriod = this.sumDays(1,30);
+      if( currentPeriod > this.get('prev30Days') ) {
+        return 'trending-up';
+      } else if ( currentPeriod < this.get('prev30Days') ) {
+        return 'trending-down';
+      }
+    }
+    return 'no-change';
+  }.property('data', 'prev30Days')
 });
 
 Discourse.Report.reopenClass({

app/assets/javascripts/admin/templates/reports/summed_counts_report.js.handlebars

@@ -1,8 +1,8 @@
 <tr>
   <td class="title"><a {{bindAttr href="reportUrl"}}>{{title}}</a></td>
   <td class="value">{{valueAtDaysAgo data 0}}</td>
-  <td class="value">{{valueAtDaysAgo data 1}}</td>
+  <td {{bindAttr class=":value yesterdayTrend"}}>{{valueAtDaysAgo data 1}} <i class="icon up icon-caret-up"></i><i class="icon down icon-caret-down"></i></td>
-  <td class="value">{{sumLast data 7}}</td>
+  <td {{bindAttr class=":value sevenDayTrend"}}>{{sumLast data 7}} <i class="icon up icon-caret-up"></i><i class="icon down icon-caret-down"></i></td>
-  <td class="value">{{sumLast data 30}}</td>
+  <td {{bindAttr class=":value thirtyDayTrend"}}>{{sumLast data 30}} <i class="icon up icon-caret-up"></i><i class="icon down icon-caret-down"></i></td>
   <td class="value">{{total}}</td>
 </tr>

app/assets/stylesheets/admin/admin_base.scss

@@ -364,6 +364,29 @@ table {
     td.value {
       font-weight: bold;
       text-align: center;
+
+      i {
+        display: none;
+      }
+
+      &.trending-up {
+        color: green;
+        i.up {
+          display: inline;
+        }
+      }
+      &.trending-down {
+        color: red;
+        i.down {
+          display: inline;
+        }
+      }
+      &.no-change {
+        i.down {
+          display: inline;
+          visibility: hidden;
+        }
+      }
     }
   }
 

app/models/report.rb

@@ -1,11 +1,12 @@
 class Report
 
-  attr_accessor :type, :data, :total
+  attr_accessor :type, :data, :total, :prev30Days
 
   def initialize(type)
     @type = type
     @data = nil
     @total = nil
+    @prev30Days = nil
   end
 
   def as_json
@@ -15,7 +16,8 @@ class Report
      xaxis: I18n.t("reports.#{self.type}.xaxis"),
      yaxis: I18n.t("reports.#{self.type}.yaxis"),
      data: self.data,
-     total: self.total
+     total: self.total,
+     prev30Days: self.prev30Days
     }
   end
 
@@ -42,6 +44,7 @@ class Report
       report.data << {x: date, y: count}
     end
     report.total = User.count
+    report.prev30Days = User.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
   def self.report_topics(report)
@@ -50,6 +53,7 @@ class Report
       report.data << {x: date, y: count}
     end
     report.total = Topic.count
+    report.prev30Days = Topic.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
   def self.report_posts(report)
@@ -58,6 +62,7 @@ class Report
       report.data << {x: date, y: count}
     end
     report.total = Post.count
+    report.prev30Days = Post.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
   def self.report_flags(report)
@@ -67,7 +72,9 @@ class Report
         report.data << {x: i.days.ago.to_date.to_s, y: count}
       end
     end
-    report.total = PostAction.where(post_action_type_id: PostActionType.flag_types.values).count
+    flagsQuery = PostAction.where(post_action_type_id: PostActionType.flag_types.values)
+    report.total = flagsQuery.count
+    report.prev30Days = flagsQuery.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
   def self.report_users_by_trust_level(report)
@@ -82,7 +89,9 @@ class Report
     PostAction.count_likes_per_day(30.days.ago).each do |date, count|
       report.data << {x: date, y: count}
     end
-    report.total = PostAction.where(post_action_type_id: PostActionType.types[:like]).count
+    likesQuery = PostAction.where(post_action_type_id: PostActionType.types[:like])
+    report.total = likesQuery.count
+    report.prev30Days = likesQuery.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
   def self.report_emails(report)
@@ -91,6 +100,7 @@ class Report
       report.data << {x: date, y: count}
     end
     report.total = EmailLog.count
+    report.prev30Days = EmailLog.where('created_at > ? and created_at < ?', 60.days.ago, 30.days.ago).count
   end
 
 end