Rename Tasks to Todos

1 files changed, 170 insertions, 0 deletions

diff --git a/app/services/todo_service.rb b/app/services/todo_service.rb
new file mode 100644
index 00000000000..dc270602ebc
--- /dev/null
+++ b/app/services/todo_service.rb
@@ -0,0 +1,170 @@
+# TodoService class
+#
+# Used for creating todos after certain user actions
+#
+# Ex.
+#   TodoService.new.new_issue(issue, current_user)
+#
+class TodoService
+  # When create an issue we should:
+  #
+  #  * create a todo for assignee if issue is assigned
+  #  * create a todo for each mentioned user on issue
+  #
+  def new_issue(issue, current_user)
+    new_issuable(issue, current_user)
+  end
+
+  # When update an issue we should:
+  #
+  #  * mark all pending todos related to the issue for the current user as done
+  #
+  def update_issue(issue, current_user)
+    create_mention_todos(issue.project, issue, current_user)
+  end
+
+  # When close an issue we should:
+  #
+  #  * mark all pending todos related to the target for the current user as done
+  #
+  def close_issue(issue, current_user)
+    mark_pending_todos_as_done(issue, current_user)
+  end
+
+  # When we reassign an issue we should:
+  #
+  #  * create a pending todo for new assignee if issue is assigned
+  #
+  def reassigned_issue(issue, current_user)
+    create_assignment_todo(issue, current_user)
+  end
+
+  # When create a merge request we should:
+  #
+  #  * creates a pending todo for assignee if merge request is assigned
+  #  * create a todo for each mentioned user on merge request
+  #
+  def new_merge_request(merge_request, current_user)
+    new_issuable(merge_request, current_user)
+  end
+
+  # When update a merge request we should:
+  #
+  #  * create a todo for each mentioned user on merge request
+  #
+  def update_merge_request(merge_request, current_user)
+    create_mention_todos(merge_request.project, merge_request, current_user)
+  end
+
+  # When close a merge request we should:
+  #
+  #  * mark all pending todos related to the target for the current user as done
+  #
+  def close_merge_request(merge_request, current_user)
+    mark_pending_todos_as_done(merge_request, current_user)
+  end
+
+  # When we reassign a merge request we should:
+  #
+  #  * creates a pending todo for new assignee if merge request is assigned
+  #
+  def reassigned_merge_request(merge_request, current_user)
+    create_assignment_todo(merge_request, current_user)
+  end
+
+  # When merge a merge request we should:
+  #
+  #  * mark all pending todos related to the target for the current user as done
+  #
+  def merge_merge_request(merge_request, current_user)
+    mark_pending_todos_as_done(merge_request, current_user)
+  end
+
+  # When create a note we should:
+  #
+  #  * mark all pending todos related to the noteable for the note author as done
+  #  * create a todo for each mentioned user on note
+  #
+  def new_note(note, current_user)
+    handle_note(note, current_user)
+  end
+
+  # When update a note we should:
+  #
+  #  * mark all pending todos related to the noteable for the current user as done
+  #  * create a todo for each new user mentioned on note
+  #
+  def update_note(note, current_user)
+    handle_note(note, current_user)
+  end
+
+  # When marking pending todos as done we should:
+  #
+  #  * mark all pending todos related to the target for the current user as done
+  #
+  def mark_pending_todos_as_done(target, user)
+    pending_todos(user, target.project, target).update_all(state: :done)
+  end
+
+  private
+
+  def create_todos(project, target, author, users, action, note = nil)
+    Array(users).each do |user|
+      next if pending_todos(user, project, target).exists?
+
+      Todo.create(
+        project: project,
+        user_id: user.id,
+        author_id: author.id,
+        target_id: target.id,
+        target_type: target.class.name,
+        action: action,
+        note: note
+      )
+    end
+  end
+
+  def new_issuable(issuable, author)
+    create_assignment_todo(issuable, author)
+    create_mention_todos(issuable.project, issuable, author)
+  end
+
+  def handle_note(note, author)
+    # Skip system notes, like status changes and cross-references
+    return if note.system
+
+    project = note.project
+    target  = note.noteable
+
+    mark_pending_todos_as_done(target, author)
+    create_mention_todos(project, target, author, note)
+  end
+
+  def create_assignment_todo(issuable, author)
+    if issuable.assignee && issuable.assignee != author
+      create_todos(issuable.project, issuable, author, issuable.assignee, Todo::ASSIGNED)
+    end
+  end
+
+  def create_mention_todos(project, issuable, author, note = nil)
+    mentioned_users = filter_mentioned_users(project, note || issuable, author)
+    create_todos(project, issuable, author, mentioned_users, Todo::MENTIONED, note)
+  end
+
+  def filter_mentioned_users(project, target, author)
+    mentioned_users = target.mentioned_users.select do |user|
+      user.can?(:read_project, project)
+    end
+
+    mentioned_users.delete(author)
+    mentioned_users.uniq
+  end
+
+  def pending_todos(user, project, target)
+    user.todos.pending.where(
+      project_id: project.id,
+      target_id: target.id,
+      target_type: target.class.name
+    )
+  end
+end