Add additional limits on sending messages

Additional limits apply to new accounts and accounts with
unresolved issues reported against them.

Fixes #3135

app/controllers/messages_controller.rb

@@ -26,7 +26,7 @@ def create
     @message.sender = current_user
     @message.sent_on = Time.now.getutc
 
-    if current_user.sent_messages.where("sent_on >= ?", Time.now.getutc - 1.hour).count >= Settings.max_messages_per_hour
+    if current_user.sent_messages.where("sent_on >= ?", Time.now.getutc - 1.hour).count >= current_user.max_messages_per_hour
       flash.now[:error] = t ".limit_exceeded"
       render :action => "new"
     elsif @message.save

app/models/issue.rb

@@ -46,7 +46,7 @@ class Issue < ApplicationRecord
 
   before_validation :set_reported_user
 
-  scope :with_status, ->(issue_status) { where(:status => statuses[issue_status]) }
+  scope :with_status, ->(issue_status) { where(:status => issue_status) }
   scope :visible_to, ->(user) { where(:assigned_role => user.roles.map(&:role)) }
 
   def read_reports

app/models/user.rb

@@ -296,6 +296,15 @@ def fingerprint
     digest.hexdigest
   end
 
+  def max_messages_per_hour
+    account_age_in_seconds = Time.now.utc - creation_time
+    account_age_in_hours = account_age_in_seconds / 3600
+    recent_messages = messages.where("sent_on >= ?", Time.now.utc - 3600).count
+    active_reports = issues.with_status(:open).sum(:reports_count)
+    max_messages = account_age_in_hours.ceil + recent_messages - active_reports * 10
+    max_messages.clamp(0, Settings.max_messages_per_hour)
+  end
+
   private
 
   def set_defaults