Initial sub-tasks support

In addition to normal dependencies, the application now supports sub-tasks. Sub-tasks can be added into any existing task (including other sub-tasks, Inception-style). Dependencies can only be added between global tasks, or between sub-tasks of the same task. It is no longer possible to mark a task as finished if it has incomplete sub-tasks, and conversedly, it is not possible to reactivate a sub-task if its parent is marked as completed. A pair of buttons allowing tasks to be moved up and down in the task hierarachy have been added.
2012-02-09 18:50:54 +01:00 · 2012-02-09 18:50:54 +01:00 · d28f5741fe
commit d28f5741fe
parent 49cc53e31f
18 changed files with 1658 additions and 132 deletions
--- a/includes/t-tasks/controllers.inc.php
+++ b/includes/t-tasks/controllers.inc.php
@ -13,6 +13,15 @@ class Ctrl_AddTask
 	}

 	public function handle( Page $page )
+	{
+		$nested = $this->form->field( 'nested' )->value( );
+		if ( 0 === (int) $nested ) {
+			return $this->addTopLevelTask( );
+		}
+		return $this->addNestedTask( );
+	}
+
+	private function addTopLevelTask( )
 	{
 		$item = $this->form->field( 'item' );
 		$name = $this->form->field( 'title' );
@ -41,6 +50,32 @@ class Ctrl_AddTask

 		return null;
 	}
+
+	private function addNestedTask( )
+	{
+		$parent = $this->form->field( 'parent' );
+		$name = $this->form->field( 'title' );
+		$priority = $this->form->field( 'priority' );
+		$description = $this->form->field( 'description' );
+
+		$error = Loader::DAO( 'tasks' )->addNestedTask( (int) $parent->value( ) ,
+			$name->value( ) , (int) $priority->value( ) , $description->value( ) );
+		switch ( $error ) {
+
+		case 0:
+			return true;
+
+		case 1:
+			$name->putError( 'Duplicate sub-task name.' );
+			break;
+
+		default:
+			$name->putError( "An unknown error occurred ($error)" );
+			break;
+		}
+
+		return null;
+	}
 }


@ -62,8 +97,13 @@ class Ctrl_TaskDetails
 		} else {
 			$bTitle = "Active task";
 		}
-		$items = Loader::DAO( 'items' );
-		$items->getLineage( $this->task->item = $items->get( $this->task->item ) );
+
+		if ( $this->task->item !== null ) {
+			$items = Loader::DAO( 'items' );
+			$items->getLineage( $this->task->item = $items->get( $this->task->item ) );
+		} else {
+			$this->task->parent_task = Loader::DAO( 'tasks' )->get( $this->task->parent_task );
+		}

 		$box = Loader::View( 'box' , $bTitle , Loader::View( 'task_details' , $this->task ) );

@ -81,6 +121,15 @@ class Ctrl_TaskDetails
 				$box->addButton( BoxButton::create( 'Claim task' , 'tasks/claim?id=' . $this->task->id )
 						->setClass( 'icon claim' ) );
 			}
+
+			if ( $this->task->can_move_up == 't' ) {
+				$box->addButton( BoxButton::create( 'Move task to grandparent' ,
+					'tasks/move/up?id=' . $this->task->id )->setClass( 'icon move-up' ) );
+			}
+			if ( ! empty( $this->task->moveDownTargets ) ) {
+				$box->addButton( BoxButton::create( 'Move task to sibling' ,
+					'tasks/move/down?id=' . $this->task->id )->setClass( 'icon move-down' ) );
+			}
 		} else {
 			if ( $tasks->canRestart( $this->task ) ) {
 				$box->addButton( BoxButton::create( 'Re-activate' , 'tasks/restart?id=' . $this->task->id )
@ -99,6 +148,32 @@ class Ctrl_TaskDetails
 }


+class Ctrl_TaskListSubtasks
+	extends Controller
+{
+	private $task;
+
+	public function __construct( $task )
+	{
+		$this->task = $task;
+	}
+
+
+	public function handle( Page $page )
+	{
+		$box = Loader::View( 'box' , 'Sub-tasks' ,
+			Loader::View( 'tasks_list' , $this->task->subtasks , array( 'deps' , 'assigned' , 'completed' ) ) );
+
+		if ( $this->task->completed_by === null ) {
+			$box->addButton( BoxButton::create( 'Add sub-task' , 'tasks/add?parent=' . $this->task->id )
+				->setClass( 'list-add' ) );
+		}
+
+		return $box;
+	}
+}
+
+
 class Ctrl_TaskDependencies
 	extends Controller
 {
@ -112,14 +187,17 @@ class Ctrl_TaskDependencies

 	public function handle( Page $page )
 	{
-		$views = array(
-			$depBox = Loader::View( 'box' , 'Dependencies' ,
-				Loader::View( 'task_dependencies' , $this->task , false ) )
-		);
+		$views = array( );

-		if ( ! empty( $this->task->possibleDependencies ) ) {
-			$depBox->addButton( BoxButton::create( 'Add dependency' , 'tasks/deps/add?to=' . $this->task->id )
-					->setClass( 'list-add' ) );
+		if ( ! empty( $this->task->dependencies )
+				|| ( $this->task->completed_by === null && ! empty( $this->task->possibleDependencies ) ) ) {
+			$views[] = ( $depBox = Loader::View( 'box' , 'Dependencies' ,
+				Loader::View( 'task_dependencies' , $this->task , false ) ) );
+
+			if ( ! empty( $this->task->possibleDependencies ) ) {
+				$depBox->addButton( BoxButton::create( 'Add dependency' , 'tasks/deps/add?to=' . $this->task->id )
+						->setClass( 'list-add' ) );
+			}
 		}

 		if ( ! empty( $this->task->reverseDependencies ) ) {
@ -230,12 +308,54 @@ class Ctrl_EditTask
 	public function handle( Page $page )
 	{
 		$id = $this->form->field( 'id' );
-		$item = $this->form->field( 'item' );
+
+		$nested = $this->form->field( 'nested' )->value( );
+		if ( 0 == (int) $nested ) {
+			$item = $this->form->field( 'item' );
+		} else {
+			$item = null;
+		}
+
 		$name = $this->form->field( 'title' );
 		$priority = $this->form->field( 'priority' );
 		$description = $this->form->field( 'description' );
 		$assignee = $this->form->field( 'assigned-to' );

+		if ( $item != null ) {
+			return $this->handleTopLevelTask( $id , $item , $name , $priority , $description , $assignee );
+		}
+		return $this->handleNestedTask(  $id , $name , $priority , $description , $assignee );
+	}
+
+	private function handleNestedTask( $id , $name , $priority , $description , $assignee )
+	{
+		$error = Loader::DAO( 'tasks' )->updateNestedTask( (int) $id->value( ) , $name->value( ) ,
+			(int) $priority->value( ) , $description->value( ) ,
+			(int) $assignee->value( ) );
+
+		switch ( $error ) {
+
+		case 0:
+			return true;
+
+		case 1:
+			$name->putError( 'Another sub-task already uses this title.' );
+			break;
+
+		case 2:
+			$assignee->putError( 'This user has been deleted.' );
+			break;
+
+		default:
+			$name->putError( "An unknown error occurred ($error)" );
+			break;
+		}
+
+		return null;
+	}
+
+	private function handleTopLevelTask( $id , $item , $name , $priority , $description , $assignee )
+	{
 		$error = Loader::DAO( 'tasks' )->updateTask( (int) $id->value( ) ,
 			(int) $item->value( ) , $name->value( ) ,
 			(int) $priority->value( ) , $description->value( ) ,
@ -373,8 +493,8 @@ class Ctrl_DependencyAdd
 	public function handle( Page $page )
 	{
 		$id = (int) $this->form->field( 'to' )->value( );
-		$dependency = $this->form->field( 'dependency' )->value( );
-		$error = Loader::DAO( 'tasks' )->addDependency( $id , $dependency );
+		$dependency = $this->form->field( 'dependency' );
+		$error = Loader::DAO( 'tasks' )->addDependency( $id , $dependency->value( ) );

 		switch ( $error ) {

@ -382,15 +502,19 @@ class Ctrl_DependencyAdd
 			return true;

 		case 1:
-			$name->putError( 'The task you selected has been deleted.' );
+			$dependency->putError( 'The task you selected has been deleted.' );
 			break;

 		case 2:
-			$item->putError( 'This dependency is no longer possible.' );
+			$dependency->putError( 'This dependency is no longer possible.' );
+			break;
+
+		case 3:
+			$dependency->putError( 'These tasks are no longer at the same level.' );
 			break;

 		default:
-			$name->putError( "An unknown error occurred ($error)" );
+			$dependency->putError( "An unknown error occurred ($error)" );
 			break;
 		}

--- a/includes/t-tasks/package.inc.php
+++ b/includes/t-tasks/package.inc.php
@ -26,9 +26,12 @@ $package[ 'ctrls' ][] = 'edit_note_form';
 $package[ 'ctrls' ][] = 'edit_note';
 $package[ 'ctrls' ][] = 'edit_task_form';
 $package[ 'ctrls' ][] = 'edit_task';
+$package[ 'ctrls' ][] = 'task_claim';
 $package[ 'ctrls' ][] = 'task_dependencies';
 $package[ 'ctrls' ][] = 'task_details';
-$package[ 'ctrls' ][] = 'task_claim';
+$package[ 'ctrls' ][] = 'task_list_subtasks';
+$package[ 'ctrls' ][] = 'task_move_down';
+$package[ 'ctrls' ][] = 'task_move_up';
 $package[ 'ctrls' ][] = 'task_notes';
 $package[ 'ctrls' ][] = 'toggle_task';
 $package[ 'ctrls' ][] = 'view_task';
--- a/includes/t-tasks/page_controllers.inc.php
+++ b/includes/t-tasks/page_controllers.inc.php
@ -75,8 +75,15 @@ class Ctrl_AddTaskForm
 	{
 		try {
 			$target = (int) $this->getParameter( 'to' );
+			$targetIsItem = true;
 		} catch ( ParameterException $e ) {
-			$target = null;
+			try {
+				$target = (int) $this->getParameter( 'parent' );
+				$targetIsItem = false;
+			} catch ( ParameterException $e ) {
+				$target = null;
+				$targetIsItem = null;
+			}
 		}

 		$form = Loader::Create( 'Form' , 'Add this task' , 'create-task' );
@ -86,20 +93,43 @@ class Ctrl_AddTaskForm
 			if ( ! $this->addItemSelector( $form ) ) {
 				return 'items';
 			}
-		} else {
+			$form->addField( Loader::Create( 'Field' , 'nested' , 'hidden' )
+				->setDefaultValue( 0 ) );
+		} elseif ( $targetIsItem ) {
 			$item = Loader::DAO( 'items' )->get( $target );
 			if ( $item === null ) {
-				return 'items';
+				return 'tasks';
 			}
 			$returnURL = 'items/view?id=' . $target;

 			$form->addField( Loader::Create( 'Field' , 'to' , 'hidden' )
 					->setDefaultValue( $target ) )
+				->addField( Loader::Create( 'Field' , 'nested' , 'hidden' )
+					->setDefaultValue( 0 ) )
 				->addField( Loader::Create( 'Field' , 'item' , 'hidden' )
 					->setDefaultValue( $target ) )
 				->addField( Loader::Create( 'Field' , 'item-name' , 'label' )
+					->setMandatory( false )
 					->setDescription( 'Item:' )
 					->setDefaultValue( $item->name ) );
+		} else {
+			$parent = Loader::DAO( 'tasks' )->get( $target );
+			if ( $parent === null ) {
+				return 'tasks';
+			}
+			$returnURL = 'tasks/view?id=' . $target;
+			if ( $parent->completed_by !== null ) {
+				return $returnURL;
+			}
+
+			$form->addField( Loader::Create( 'Field' , 'parent' , 'hidden' )
+					->setDefaultValue( $target ) )
+				->addField( Loader::Create( 'Field' , 'nested' , 'hidden' )
+					->setDefaultValue( 1 ) )
+				->addField( Loader::Create( 'Field' , 'item-name' , 'label' )
+					->setMandatory( false )
+					->setDescription( 'Sub-task of:' )
+					->setDefaultValue( $parent->title ) );
 		}

 		$page->setTitle( 'New task' );
@ -159,10 +189,13 @@ class Ctrl_ViewTask
 		$page->setTitle( $task->title . ' (task)' );

 		$result = array(
-			Loader::Ctrl( 'task_details' , $task ) ,
-			Loader::Ctrl( 'task_dependencies' , $task ) ,
+			Loader::Ctrl( 'task_details' , $task )
 		);

+		if ( $task->completed_by === null || ! empty( $task->subtasks ) ) {
+			$result[] = Loader::Ctrl( 'task_list_subtasks' , $task );
+		}
+		$result[] = Loader::Ctrl( 'task_dependencies' , $task );
 		if ( $task->completed_by === null ) {
 			array_push( $result , Loader::Ctrl( 'add_task_note_form' , $task ) );
 		}
@ -197,6 +230,13 @@ class Ctrl_DeleteTaskForm
 		}
 		$page->setTitle( $task->title . ' (task)' );

+		// Create parent URL from either the item or parent task
+		if ( $task->parent_task === null ) {
+			$parentURL = 'items/view?id=' . $task->item;
+		} else {
+			$parentURL = 'tasks/view?id=' . $task->parent_task;
+		}
+
 		// Generate confirmation text
 		$confText = HTML::make( 'div' )
 			->appendElement( HTML::make( 'p' )
@ -210,7 +250,7 @@ class Ctrl_DeleteTaskForm
 				->setDefaultValue( $task->id ) )
 			->addField( Loader::Create( 'Field' , 'confirm' , 'html' )->setDefaultValue( $confText ) )
 			->setCancelURL( 'tasks/view?id=' . $task->id )
-			->setSuccessURL( 'items/view?id=' . $task->item )
+			->setSuccessURL( $parentURL )
 			->addController( Loader::Ctrl( 'delete_task' ) )
 			->controller( );

@ -242,13 +282,19 @@ class Ctrl_EditTaskForm
 		$page->setTitle( $task->title . ' (task)' );


-		return Loader::Create( 'Form' , 'Update task' , 'edit-task' , 'Editing task' )
+		$form = Loader::Create( 'Form' , 'Update task' , 'edit-task' , 'Editing task' )
 			->setURL( 'tasks/view?id=' . $task->id )
 			->addField( Loader::Create( 'Field' , 'id' , 'hidden' )
 				->setDefaultValue( $task->id ) )
-			->addField( $this->createItemSelector( )
-				->setDefaultValue( $task->item ) )
-			->addField( Loader::Create( 'Field' , 'title' , 'text' )
+			->addField( Loader::Create( 'Field' , 'nested' , 'hidden' )
+				->setDefaultValue( $task->item === null ? 1 : 0 ) );
+
+		if ( $task->item !== null ) {
+			$form->addField( $this->createItemSelector( )
+				->setDefaultValue( $task->item ) );
+		}
+
+		return $form->addField( Loader::Create( 'Field' , 'title' , 'text' )
 				->setDescription( 'Title:' )
 				->setModifier( Loader::Create( 'Modifier_TrimString' ) )
 				->setValidator( Loader::Create( 'Validator_StringLength' , 'This title' , 5 , 256 ) )
@ -411,31 +457,37 @@ class Ctrl_DependencyAddForm
 		$form = Loader::Create( 'Form' , 'Add dependency' , 'add-dep' )
 			->addField( Loader::Create( 'Field' , 'to' , 'hidden' )
 			->setDefaultValue( $id ) );
-		$this->addDependencySelector( $form , $task->possibleDependencies );
+		$this->addDependencySelector( $form , $task->possibleDependencies , $task->item !== null );
 		return $form->setURL( 'tasks/view?id=' . $id )
 			->addController( Loader::Ctrl( 'dependency_add' ) )
 			->controller( );

 	}

-	private function addDependencySelector( $form , $possibleDependencies )
+	private function addDependencySelector( $form , $possibleDependencies , $topLevel )
 	{
 		$form->addField( $select = Loader::Create( 'Field' , 'dependency' , 'select' )
 			->setDescription( 'Dependency to add:' )
 			->addOption( '' , '(please select a task)' ) );

-		$depsByItem = $this->getDependenciesByItem( $possibleDependencies );
-		$items = $this->getItemsToDisplay( $depsByItem );
-		foreach ( $items as $item ) {
-			$prefix = '-' . str_repeat( '--' , $item->depth );
-			$name = $prefix . ' ' . $item->name;
-			$select->addOption( 'I' . $item->id , $name , true );
-			if ( ! array_key_exists( $item->id , $depsByItem ) ) {
-				continue;
-			}
+		if ( $topLevel ) {
+			$depsByItem = $this->getDependenciesByItem( $possibleDependencies );
+			$items = $this->getItemsToDisplay( $depsByItem );
+			foreach ( $items as $item ) {
+				$prefix = '-' . str_repeat( '--' , $item->depth );
+				$name = $prefix . ' ' . $item->name;
+				$select->addOption( 'I' . $item->id , $name , true );
+				if ( ! array_key_exists( $item->id , $depsByItem ) ) {
+					continue;
+				}

-			foreach ( $depsByItem[ $item->id ] as $task ) {
-				$select->addOption( $task->id , $prefix . '-> ' . $task->title );
+				foreach ( $depsByItem[ $item->id ] as $task ) {
+					$select->addOption( $task->id , $prefix . '-> ' . $task->title );
+				}
+			}
+		} else {
+			foreach ( $possibleDependencies as $task ) {
+				$select->addOption( $task->id , $task->title );
 			}
 		}
 		return true;
@ -546,3 +598,155 @@ class Ctrl_DependencyDeleteForm
 }


+
+class Ctrl_TaskMoveDown
+	extends Controller
+{
+
+	public function __construct( )
+	{
+		$this->dao = Loader::DAO( 'tasks' );
+	}
+
+	public function handle( Page $page )
+	{
+		try {
+			$id = (int) $this->getParameter( 'id' );
+		} catch ( ParameterException $e ) {
+			return 'tasks';
+		}
+
+		$task = $this->dao->get( $id );
+		if ( $task === null ) {
+			return 'tasks';
+		}
+
+		if ( empty( $task->moveDownTargets ) ) {
+			return 'tasks/view?id=' . $id;
+		}
+
+		$page->setTitle( $task->title . ' (task)' );
+		$sibling = $this->getSibling( $task );
+		if ( $sibling != null ) {
+			if ( $this->handleSelectedSibling( $task , $sibling ) ) {
+				return 'tasks/view?id=' . $id;
+			} else {
+				return $this->confirmationForm( $task , $sibling );
+			}
+		}
+		return $this->siblingSelectionForm( $task );
+	}
+
+	private function getSibling( $task )
+	{
+		try {
+			$sibling = (int) $this->getParameter( 'sibling' );
+			$okSiblings = array_map( function( $item ) { return $item->target_id; } , $task->moveDownTargets );
+			if ( ! in_array( $sibling , $okSiblings ) ) {
+				$sibling = null;
+			}
+		} catch ( ParameterException $e ) {
+			$sibling = null;
+		}
+		return $sibling;
+	}
+
+	private function handleSelectedSibling( $task , $sibling )
+	{
+		try {
+			$force = (bool) $this->getParameter( 'force' );
+		} catch ( ParameterException $e ) {
+			$force = false;
+		}
+
+		return $this->dao->moveDown( $task , $sibling , $force );
+	}
+
+	private function confirmationForm( $task , $sibling )
+	{
+		$sibling = $this->dao->get( $sibling );
+		$confText = HTML::make( 'div' )
+			->appendElement( HTML::make( 'p' )
+				->appendText( 'All dependencies and reverse dependencies of the '
+					. 'selected task will be lost when it is moved into ' )
+				->appendElement( HTML::make( 'strong' )->appendText( $sibling->title ) )
+				->appendText( '.' ) )
+			->appendElement( HTML::make( 'p' )
+				->appendText( 'Please confirm.' ) );
+
+		return Loader::Create( 'Form' , 'Move task' , 'move-down' )
+			->addField( Loader::Create( 'Field' , 'id' , 'hidden' )
+				->setDefaultValue( $task->id ) )
+			->addField( Loader::Create( 'Field' , 'sibling' , 'hidden' )
+				->setDefaultValue( $sibling->id ) )
+			->addField( Loader::Create( 'Field' , 'force' , 'hidden' )
+				->setDefaultValue( 1 ) )
+			->addField( Loader::Create( 'Field' , 'confirm' , 'html' )->setDefaultValue( $confText ) )
+			->setURL( 'tasks/view?id=' . $task->id )
+			->controller( );
+	}
+
+	private function siblingSelectionForm( $task )
+	{
+		$selector = Loader::Create( 'Field' , 'sibling' , 'select' )
+			->setDescription( 'Move task into: ' );
+		foreach ( $task->moveDownTargets as $target ) {
+			$selector->addOption( $target->target_id , $target->target_title );
+		}
+		return Loader::Create( 'Form' , 'Move task' , 'move-down' , 'Move task to sibling' )
+			->addField( Loader::Create( 'Field' , 'id' , 'hidden' )
+				->setDefaultValue( $task->id ) )
+			->addField( $selector )
+			->setURL( 'tasks/view?id=' . $task->id )
+			->controller( );
+	}
+}
+
+
+class Ctrl_TaskMoveUp
+	extends Controller
+{
+
+	public function handle( Page $page )
+	{
+		try {
+			$id = (int) $this->getParameter( 'id' );
+		} catch ( ParameterException $e ) {
+			return 'tasks';
+		}
+
+		$dao = Loader::DAO( 'tasks' );
+		$task = $dao->get( $id );
+		if ( $task === null ) {
+			return 'tasks';
+		}
+
+		try {
+			$force = (bool) $this->getParameter( 'force' );
+		} catch ( ParameterException $e ) {
+			$force = false;
+		}
+
+		if ( ! $task->can_move_up || $dao->moveUp( $task , $force ) ) {
+			return 'tasks/view?id=' . $id;
+		}
+
+		$confText = HTML::make( 'div' )
+			->appendElement( HTML::make( 'p' )
+				->appendText( 'All dependencies and reverse dependencies of the '
+					. 'selected task will be lost when it is moved.' ) )
+			->appendElement( HTML::make( 'p' )
+				->appendText( 'Please confirm.' ) );
+
+		$page->setTitle( $task->title . ' (task)' );
+		return Loader::Create( 'Form' , 'Move task' , 'move-up' )
+			->addField( Loader::Create( 'Field' , 'id' , 'hidden' )
+				->setDefaultValue( $id ) )
+			->addField( Loader::Create( 'Field' , 'force' , 'hidden' )
+				->setDefaultValue( 1 ) )
+			->addField( Loader::Create( 'Field' , 'confirm' , 'html' )->setDefaultValue( $confText ) )
+			->setURL( 'tasks/view?id=' . $id )
+			->controller( );
+	}
+
+}
--- a/includes/t-tasks/pages.inc.php
+++ b/includes/t-tasks/pages.inc.php
@ -15,10 +15,12 @@ class Page_TasksTasks
 			'finish'	=> array( 'toggle_task' , false ) ,
 			'restart'	=> array( 'toggle_task' , true ) ,
 			'view'		=> 'view_task' ,
-			'notes/edit'	=> 'edit_note_form' ,
-			'notes/delete'	=> 'delete_note_form' ,
 			'deps/add'	=> 'dependency_add_form' ,
 			'deps/delete'	=> 'dependency_delete_form' ,
+			'move/down'	=> 'task_move_down' ,
+			'move/up'	=> 'task_move_up' ,
+			'notes/edit'	=> 'edit_note_form' ,
+			'notes/delete'	=> 'delete_note_form' ,
 		));
 	}

--- a/includes/t-tasks/views.inc.php
+++ b/includes/t-tasks/views.inc.php
@ -60,7 +60,7 @@ class View_TasksList
 			->appendElement( HTML::make( 'a' )
 				->setAttribute( 'href' , $this->base . '/tasks/view?id=' . $task->id )
 				->appendText( $task->title ) ) );
-		$this->addItem( $cell , $task );
+		$this->addParent( $cell , $task );
 		$classes = array( );

 		$addedAt = strtotime( $task->added_at );
@ -75,6 +75,9 @@ class View_TasksList
 			if ( $task->missing_dependencies !== null ) {
 				$this->generateMissingDependencies( $cell , $classes , $task );
 			}
+			if ( $task->missing_subtasks !== null ) {
+				$this->generateMissingSubtasks( $cell , $classes , $task );
+			}
 			if ( $task->assigned_to !== null ) {
 				$this->generateAssignedTask( $cell , $classes , $task );
 			}
@ -82,19 +85,28 @@ class View_TasksList

 		if ( ! empty( $classes ) ) {
 			foreach ( $cell as $entry ) {
-				$entry->setAttribute( 'class' , join( ' ' , $classes ) );
+				$entry->setAttribute( 'class' , join( ' ' , array_unique( $classes ) ) );
 			}
 		}

 		return $cell;
 	}

-	protected function addItem( &$cell , $task )
+	protected function addParent( &$cell , $task )
 	{
 		if ( ! array_key_exists( 'item' , $this->features ) ) {
 			return;
 		}

+		if ( $task->item !== null ) {
+			$this->addItem( $cell , $task );
+		} else {
+			$this->addParentTask( $cell , $task );
+		}
+	}
+
+	protected function addItem( &$cell , $task )
+	{
 		$itemsDao = Loader::DAO( 'items' );
 		$item = $itemsDao->get( $task->item );
 		$lineage = $itemsDao->getLineage( $item );
@ -114,6 +126,17 @@ class View_TasksList
 		array_push( $cell , HTML::make( 'dd' )->append( $contents ) );
 	}

+	protected function addParentTask( &$cell , $task )
+	{
+		$parent = $this->dao->get( $task->parent_task );
+
+		array_push( $cell , HTML::make( 'dd' )
+			->appendText( 'Sub-task of ' )
+			->appendElement( HTML::make( 'a' )
+				->setAttribute( 'href' , $this->base . '/tasks/view?id=' . $parent->id )
+				->appendText( $parent->title ) ) );
+	}
+
 	protected function generateMissingDependencies( &$cell , &$classes , $task )
 	{
 		if ( ! array_key_exists( 'deps' , $this->features ) ) {
@ -134,6 +157,23 @@ class View_TasksList
 		array_push( $classes , 'missing-deps' );
 	}

+	protected function generateMissingSubtasks( &$cell , &$classes , $task )
+	{
+		if ( ! array_key_exists( 'deps' , $this->features ) ) {
+			return;
+		}
+
+		if ( $task->missing_subtasks > 1 ) {
+			$end = 's';
+		} else {
+			$end = '';
+		}
+		array_push( $cell ,
+			$md = HTML::make( 'dd' )->appendText( "{$task->missing_subtasks} incomplete sub-task$end" ) );
+
+		array_push( $classes , 'missing-deps' );
+	}
+
 	protected function generateAssignedTask( &$cell , &$classes , $task )
 	{
 		if ( ! array_key_exists( 'assigned' , $this->features ) ) {
@ -173,11 +213,22 @@ class View_TaskDetails
 	public function render( )
 	{
 		$list = HTML::make( 'dl' )
-			->setAttribute( 'class' , 'tasks' )
-			->appendElement( HTML::make( 'dt' )
-				->appendText( 'On item:' ) )
-			->appendElement( HTML::make( 'dd' )
-				->append( $this->formatPlaceLineage( $this->task->item ) ) );
+			->setAttribute( 'class' , 'tasks' );
+
+		if ( $this->task->item !== null ) {
+			$list->appendElement( HTML::make( 'dt' )
+					->appendText( 'On item:' ) )
+				->appendElement( HTML::make( 'dd' )
+					->append( $this->formatPlaceLineage( $this->task->item ) ) );
+		} else {
+			$list->appendElement( HTML::make( 'dt' )
+					->appendText( 'Sub-task of:' ) )
+				->appendElement( HTML::make( 'dd' )
+					->appendElement( HTML::make( 'a' )
+						->setAttribute( 'href' , $this->base .
+							'/tasks/view?id=' . $this->task->parent_task->id )
+						->appendText( $this->task->parent_task->title ) ) );
+		}

 		if ( $this->task->description != '' ) {
 			$list->appendElement( HTML::make( 'dt' )
@ -317,6 +368,8 @@ class View_TaskDependencies
 						->appendText( $dependency->item_name ) )
 					->appendElement( $itemList ) );
 				$prevItem = $dependency->item;
+			} elseif ( $itemList === null ) {
+				$itemList = $list;
 			}

 			$entry = HTML::make( 'li' )->appendElement(