6 files changed, 200 insertions, 2 deletions
diff --git a/app/frontend/dto/CalendarGridDTO.php b/app/frontend/dto/CalendarGridDTO.php
index f5d91a5..c6f1d00 100644
--- a/app/frontend/dto/CalendarGridDTO.php
+++ b/app/frontend/dto/CalendarGridDTO.php
@@ -69,7 +69,7 @@ class CalendarGridDTO {
         return $events;
     }
 
-    private function _getGridDay(DateTimeImmutable $date,
+    protected function _getGridDay(DateTimeImmutable $date,
                                  array $events,
                                  CalendarGridDayDTO $previousDay = NULL) {
         $day = new CalendarGridDayDTO($date, $events);
diff --git a/app/frontend/dto/GridEventDTO.php b/app/frontend/dto/GridEventDTO.php
index 0d2bb37..ca985f0 100644
--- a/app/frontend/dto/GridEventDTO.php
+++ b/app/frontend/dto/GridEventDTO.php
@@ -1,8 +1,9 @@
 <?php
 
 Prado::using('Application.dto.EventDTO');
+Prado::using('Application.controls.grid.IGridElementDTO');
 
-class GridEventDTO extends EventDTO {
+class GridEventDTO extends EventDTO implements IGridElementDTO {
 
     public $DateFrom;
     public $DateTo;
@@ -23,6 +24,10 @@ class GridEventDTO extends EventDTO {
         return $ev1->GridPosition - $ev2->GridPosition;
     }
 
+    public function getRendererClass() {
+        return 'Event';
+    }
+
 }
 
 ?>
diff --git a/app/frontend/dto/GridEventGroupDTO.php b/app/frontend/dto/GridEventGroupDTO.php
new file mode 100644
index 0000000..5845076
--- /dev/null
+++ b/app/frontend/dto/GridEventGroupDTO.php
@@ -0,0 +1,73 @@
+<?php
+
+Prado::using('Application.dto.GridEventDTO');
+Prado::using('Application.controls.grid.IGridElementDTO');
+
+class GridEventGroupDTO implements IGridElementDTO {
+
+    public $Header;
+    public $Events;
+    public $Calendar;
+    public $GridPosition;
+
+    public function __construct(array $events) {
+        $this->Events = $events;
+        if ($this->Events) {
+            $this->Calendar = $this->Events[0]->Calendar;
+        }
+        usort($this->Events, ['GridEventDTO', '__compare']);
+        $this->Header = $this->_determineCommonHeader($this->Events);
+    }
+
+    public static function __compare(GridEventGroupDTO $ev1, GridEventGroupDTO $ev2) {
+        if ($ev1->GridPosition === NULL || $ev2->GridPosition === NULL) {
+            if (count($ev1->Events) && count($ev2->Events)) {
+                return EventDTO::__compare($ev1->Events[0], $ev2->Events[0]);
+            }
+        }
+        return $ev1->GridPosition - $ev2->GridPosition;
+    }
+
+    private function _determineCommonHeader(array $events) {
+        if (!$events) {
+            return NULL;
+        }
+        $names = array_map(
+            function(EventDTO $event) {
+                return $event->Name;
+            },
+            $events
+        );
+        $prefix = $names[0];
+        $passed = FALSE;
+        while (!$passed && $prefix) {
+            $passed = TRUE;
+            $prefixLength = strlen($prefix);
+            foreach ($names as $name) {
+                if (substr($name, 0, $prefixLength) != $prefix) {
+                    $passed = FALSE;
+                    break;
+                }
+            }
+            if ($passed) {
+                foreach ($names as $name) {
+                    if (is_numeric(trim(substr($name, $prefixLength)))) {
+                        $passed = FALSE;
+                        break;
+                    }
+                }
+            }
+            if (!$passed) {
+                $prefix = substr($prefix, 0, strrpos($prefix, ' '));
+            }
+        }
+        return $prefix ?: $events[0]->Calendar->Name;
+    }
+
+    public function getRendererClass() {
+        return 'Group';
+    }
+
+}
+
+?>
diff --git a/app/frontend/dto/GroupedCalendarGridDTO.php b/app/frontend/dto/GroupedCalendarGridDTO.php
new file mode 100644
index 0000000..401d8c2
--- /dev/null
+++ b/app/frontend/dto/GroupedCalendarGridDTO.php
@@ -0,0 +1,70 @@
+<?php
+
+Prado::using('Application.dto.GroupedCalendarGridDayDTO');
+Prado::using('Application.dto.GridEventDTO');
+
+class GroupedCalendarGridDTO extends CalendarGridDTO {
+
+    private function _getContinuedEventGridPositions(
+        CalendarGridDayDTO $day,
+        CalendarGridDayDTO $previousDay = NULL) {
+        $eventPositions = [];
+        if ($previousDay) {
+            foreach ($day->Events as $group) {
+                foreach ($previousDay->Events as $pGroup) {
+                    if ($group && $pGroup) {
+                        if ($group->Calendar == $pGroup->Calendar) {
+                            $group->GridPosition = $pGroup->GridPosition;
+                            $eventPositions[] = $group->GridPosition;
+                        }
+                    }
+                }
+            }
+        }
+        return $eventPositions;
+    }
+
+    private function _alignEvents(array $eventPositions, array $events) {
+        $previousCount = count($eventPositions);
+        foreach ($events as $event) {
+            if ($event->GridPosition === NULL) {
+                $event->GridPosition = min(
+                    array_diff(
+                        range(0, count($events) + $previousCount),
+                        $eventPositions
+                    )
+                );
+                $eventPositions[] = $event->GridPosition;
+            }
+        }
+        usort($events, ['GridEventGroupDTO', '__compare']);
+        return $events;
+    }
+
+    private function _fillEventGrid(array $events) {
+        $previousEvent = -1;
+        foreach ($events as $event) {
+            $eventStep = $event->GridPosition - $previousEvent;
+            if ($eventStep > 1) {
+                array_splice(
+                    $events, $previousEvent + 1, 0, array_fill(0, $eventStep - 1, NULL)
+                );
+            }
+            $previousEvent = $event->GridPosition;
+        }
+        return $events;
+    }
+
+    protected function _getGridDay(DateTimeImmutable $date,
+                                 array $events,
+                                 CalendarGridDayDTO $previousDay = NULL) {
+        $day = new GroupedCalendarGridDayDTO($date, $events);
+        $eventPositions = $this->_getContinuedEventGridPositions($day, $previousDay);
+        $day->Events = $this->_alignEvents($eventPositions, $day->Events);
+        $day->Events = $this->_fillEventGrid($day->Events);
+        return $day;
+    }
+
+}
+
+?>
diff --git a/app/frontend/dto/GroupedCalendarGridDayDTO.php b/app/frontend/dto/GroupedCalendarGridDayDTO.php
new file mode 100644
index 0000000..7d2c041
--- /dev/null
+++ b/app/frontend/dto/GroupedCalendarGridDayDTO.php
@@ -0,0 +1,33 @@
+<?php
+
+Prado::using('Application.dto.CalendarGridDayDTO');
+Prado::using('Application.dto.GridEventGroupDTO');
+
+class GroupedCalendarGridDayDTO extends CalendarGridDayDTO {
+
+    public function __construct(DateTimeImmutable $date, array $events) {
+        parent::__construct($date, $events);
+        $this->Events = $this->_getEventGroups($this->Events);
+        // initial sort events are going to be re-sorted after assigning grid priorities
+        usort($this->Events, ['GridEventGroupDTO', '__compare']);
+    }
+
+    private function _getEventGroups(array $events) {
+        $clusters = [];
+        foreach ($events as $event) {
+            if (!isset($clusters[$event->Calendar->ID])) {
+                $clusters[$event->Calendar->ID] = [];
+            }
+            $clusters[$event->Calendar->ID][] = $event;
+        }
+        return array_map(
+            function($cluster) {
+                return new GridEventGroupDTO($cluster);
+            },
+            $clusters
+        );
+    }
+
+}
+
+?>
diff --git a/app/frontend/dto/GroupedGridEventDTO.php b/app/frontend/dto/GroupedGridEventDTO.php
new file mode 100644
index 0000000..e9e9d0b
--- /dev/null
+++ b/app/frontend/dto/GroupedGridEventDTO.php
@@ -0,0 +1,17 @@
+<?php
+
+Prado::using('Application.dto.GridEventDTO');
+
+class GroupedGridEventDTO extends GridEventDTO {
+
+    public $DateFrom;
+    public $DateTo;
+    public $AllDay;
+
+    public static function __compare(EventDTO $ev1, EventDTO $ev2) {
+        return EventDTO::__compare($ev1, $ev2);
+    }
+
+}
+
+?>