# HG changeset patch
# User olivier
# Date 1475241267 -7200
#      Fri Sep 30 15:14:27 2016 +0200
# Node ID 79a189f1725546f9eb803831056015f23b10fb63
# Parent  da5e814314dfe7b63431556479ed37f3bf85b5d0
When issues are from multiple projects, set project to be the lowest common
parent of all listed issues instead of nil

diff -r da5e814314df -r 79a189f17255 app/controllers/application_controller.rb
--- a/app/controllers/application_controller.rb	Thu Sep 22 14:31:27 2016 +0200
+++ b/app/controllers/application_controller.rb	Fri Sep 30 15:14:27 2016 +0200
@@ -294,6 +294,21 @@
     render_404
   end
 
+  # Find the first common parent of two projects
+  def find_common_parent(project1, project2)
+    return nil if project1.nil? || project2.nil?
+    return project1 if project1.id == project2.id
+    p1_ancestors = [project1.id]
+    while !project1.parent_id.nil?
+      p1_ancestors << project1.parent_id
+      project1 = Project.find(project1.parent_id)
+    end
+    while !project2.parent_id.nil? && !p1_ancestors.include?(project2.parent_id)
+      project2 = Project.find(project2.parent_id)
+    end
+    project2.parent_id.nil? ? nil : Project.find(project2.parent_id)
+  end
+
   # Finds and sets @project based on @object.project
   def find_project_from_association
     render_404 unless @object.present?
@@ -337,7 +352,14 @@
     raise ActiveRecord::RecordNotFound if @issues.empty?
     raise Unauthorized unless @issues.all?(&:visible?)
     @projects = @issues.collect(&:project).compact.uniq
-    @project = @projects.first if @projects.size == 1
+    # Get the highest common parent project in the project tree
+    common_parent = @projects.first
+    Project.project_tree(@projects) do |project, level|
+      if level == 0
+        common_parent = find_common_parent(common_parent, project)
+      end  
+    end
+    @project = common_parent
   rescue ActiveRecord::RecordNotFound
     render_404
   end