diff --git a/api/app/Http/Controllers/ProgramController.php b/api/app/Http/Controllers/ProgramController.php
index 3fd535b..c5d6802 100644
--- a/api/app/Http/Controllers/ProgramController.php
+++ b/api/app/Http/Controllers/ProgramController.php
@@ -18,7 +18,7 @@ class ProgramController extends Controller
               ((`schedule`.`enddate` IS NULL) OR (`schedule`.`enddate` >= :startdate)) AND
              `schedule`.`active` = 1 AND
              `schedule`.`final` = 1 
-        ORDER BY `schedule`.`priority` DESC, MOD(`startday` + 6, 7) + 1, `schedule`.`starttime` ASC
+        ORDER BY `schedule`.`priority` DESC, `schedule`.`startday` ASC, `schedule`.`starttime` ASC
 QUERY;
 
     /**
@@ -30,6 +30,153 @@ QUERY;
     {
         //
     }
+ 
+    public function addToSchedule(&$schedule, $start, $end, $program) {
+      if($start == $end) { 
+        return; 
+      }
+
+      $last = count($schedule) ? $schedule[count($schedule) - 1] : null;
+      if($last && ($last['program'] == $program) && ($last['end'] == $start))
+      {
+        // Merge with the previous entry
+        $last['end'] = $end;
+      } 
+      else
+      {
+        $schedule[] = ['start' => clone $start, 'end' => clone $end, 'program' => new \Model\Program($program)];
+      }
+    }
+
+
+    public function createSchedule(\DateTimeImmutable $start, \DateTimeImmutable $end, $DEBUG = false) {
+      $startDay = $start->format('N');
+      $endDay = $end->format('N');
+      $schedule = [];
+  
+      $START = 1; $END = -1;
+      $WEEK = new \DateInterval('P7D');
+      $WEEKDAYS = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" /* == 0 and 7 */];
+      $scheduleItems = app('db')->select(self::$SCHEDULE_SQL,
+          ['enddate' => $end->format('Y-m-d'), 'startdate' => $start->format('Y-m-d')]);
+      $scheduleChanges = new \SplPriorityQueue();
+      $active = [];
+      foreach($scheduleItems as $item) {
+        // Find the start time and end time of the last occurrence on or before the start time
+        $itemStart = new \DateTime("last " . $WEEKDAYS[$item->startday] . " " . $start->format('Y-m-d') . " " . $item->starttime);
+        $itemEnd = new \DateTime("last " . $WEEKDAYS[$item->endday] . " " . $start->format('Y-m-d') . " " . $item->endtime);
+        if($itemEnd <= $itemStart) {
+          $itemEnd->add($WEEK);
+        }
+
+        // If the first occurrence is completely before the period of interest, look at the next week
+        while($itemEnd < $start) { 
+          $itemStart->add($WEEK);
+          $itemEnd->add($WEEK);
+        }
+
+        // Create a list in which all start and end times are separate entries
+        $scheduleChanges->insert( [$START, $itemStart, $item], [-$itemStart->getTimestamp(), -$START] );
+        $scheduleChanges->insert( [$END, $itemEnd, $item], [-$itemEnd->getTimestamp(), -$END] );
+
+        // Also keep track of all priorities seen
+        $active[$item->priority] = null;
+      }
+
+      if($DEBUG) { 
+        print "<h2>Schedule changes - initial state</h2><ul>";
+        foreach(clone $scheduleChanges as $c) { 
+          print "<li>{$c[1]->format('d-m-Y H:i')}: " . ($c[0] == $START ? 'Start' : 'Einde') . " {$c[2]->name} {$c[2]->suffix}</li>";
+        }
+        print "</ul><hr/>";
+      }
+
+      // Go through all programs and keep going until we have one that starts after the end date.
+      $activeProgram = null;
+      $activeProgramStart = null;
+      while(true) {
+        $item = $scheduleChanges->extract();
+
+        if($DEBUG) print "<b>{$item[1]->format('d-m-Y H:i')}: {$item[2]->name} " . ($item[0] == $START ? "begint" : "eindigt") . "</b><br/>";
+
+        // If we passed the end time, we are (almost) done
+        if($item[1] > $end) {
+          if($DEBUG) { print "Reached end at {$item[1]->format('d-m-Y H:i')} ({$item[2]->name}).<br/>"; }
+          break;
+        }
+  
+        $priority = $item[2]->priority;
+        if($item[0] == $START) { 
+          if($active[$priority] != null) { 
+            print( "<b>Error:</b>" . $item[2]->name . ' starts at ' . $item[1]->format('d-m-Y H:i') . ' but ' . $active[$priority]->name . ' is still active then.' );
+            print "<pre>"; var_dump($active); print "</pre>";
+          }
+  
+          // When a program starts, it becomes the active program in its layer
+          $active[$priority] = $item[2];
+
+          // In addition, if it has higher priority than the currently active program, it replaces that. 
+          if($activeProgram == null || $priority < $activeProgram->priority) {
+              if(($activeProgram != null) && ($item[1] > $start)) {
+                if($DEBUG) print "{$activeProgramStart->format('d-m-Y H:i')} -- {$item[1]->format('d-m-Y H:i')}: {$activeProgram->name} (reason: {$item[2]->name} starts).<br/>";
+                $this->addToSchedule($schedule, $activeProgramStart, $item[1], $activeProgram);
+              }
+
+            $activeProgramStart = ($item[1] < $start) ? $start : clone $item[1];
+            $activeProgram = $item[2];
+          }
+
+        } else if($item[0] == $END) {
+          if($active[$priority] == null) {
+            print( "<b>Error:</b>" . $item[2]->name . ' ends at ' . $item[1]->format('d-m-Y H:i') . ' but no program is active at that priority and timestamp.');
+            print "<pre>"; var_dump($active); print "</pre>";
+          } 
+
+          // When the program ends, its layer becomes inactive.
+          $active[$priority] = null;
+
+          // In addition, when the ending program was the active program, we need to schedule it and find the new currently active program
+          if($activeProgram == $item[2]) {
+            if($DEBUG) print "{$activeProgramStart->format('d-m-Y H:i')} -- {$item[1]->format('d-m-Y H:i')}: {$activeProgram->name} (reason: {$item[2]->name} ends).<br/>";
+            $this->addToSchedule($schedule, $activeProgramStart, $item[1], $activeProgram);
+
+            $activeProgram = null;
+            foreach($active as $newPriority => $newActive) { 
+              if(($newActive != null) && ($activeProgram == null || $newPriority < $activeProgram->priority)) {
+                $activeProgram = $newActive;
+              }
+            }
+
+            if($activeProgram != null) {
+              $activeProgramStart = clone $item[1];
+            }
+
+            if($DEBUG) print "  New active program is " . ($activeProgram ? $activeProgram->name : "---") . "<br/>";
+          }
+        } else {
+          return response()->abort(500, "Invalid item type: expected START ($START) or END ($END), but got {$item[0]}.");
+        }
+
+        // The item will recur in a week
+        $item[1]->add($WEEK);
+        $scheduleChanges->insert($item, [-$item[1]->getTimestamp(), -$item[0]]);
+      }
+
+      if(($activeProgram != null) && ($activeProgramStart != $end)) {
+        if($DEBUG) print "{$activeProgramStart->format('d-m-Y H:i')} -- {$end->format('d-m-Y H:i')}: {$activeProgram->name} (reason: schedule finished).<br/>";
+        $this->addToSchedule($schedule, $activeProgramStart, $end, $activeProgram);
+      }
+
+      return ['startdate' => $start, 'enddate' => $end, 'schedule' => $schedule];
+    }
+
+    public function testSchedule($from, $to)
+    {
+      $start = new \DateTimeImmutable(urldecode($from));
+      $end = new \DateTimeImmutable(urldecode($to));
+      $this->createSchedule($start, $end, true);
+    }
+  
 
     /**
     * Details over een specifiek programma, inclusief schema en podcasts
@@ -51,88 +198,14 @@ QUERY;
             AND `user_emailaddresses`.`preference` = 0
             AND `programs_users`.`active` = 1
           ORDER BY `name`", ['program' => $program->id]);
+
       foreach($hosts as $host) {
         $program->hosts[] = new \Model\ProgramHost($host);
       }
 
-      $schedule = app('db')->select(<<<QUERY
-    SELECT `schedule`.`startdate`, `schedule`.`startday`, `schedule`.`starttime`, `schedule`.`enddate`, `schedule`.`endday`, `schedule`.`endtime`, `schedule`.`shortnamesuffix` AS `suffix`, `schedule`.`priority`
-        FROM `programs_schedule` AS `schedule` 
-        WHERE (schedule.`program` = :program) AND (`schedule`.`active` = 1) AND (`schedule`.`final` = 1)
-        ORDER BY `schedule`.`priority` DESC, MOD(`startday` + 6, 7) + 1, `schedule`.`starttime` ASC
-QUERY
-      , ['program' => $program->id] );
-      $recentSchedule = $this->recent($schedule);
-      $program->schedule = $recentSchedule;
-
       return response()->json($program);
     }
 
-    private function recent($schedule) { 
-      $now = new \DateTimeImmutable();
-      $ONE_DAY = \DateInterval::createFromDateString('1 day');
-      $ONE_WEEK = \DateInterval::createFromDateString('1 week');
-      $recent = [];
-      $next = [];
-
-      // Vind voor elke regel in de uitzendmomenten de eerstvolgende en twee meest recente.
-      $isCurrent = false;
-      foreach($schedule as $broadcast) {
-        $broadcast->startdate = ($broadcast->startdate == null) ? null : new \DateTimeImmutable($broadcast->startdate);
-        $broadcast->enddate = ($broadcast->enddate == null) ? null : new \DateTimeImmutable($broadcast->enddate);
-        $startTijd = new \DateTimeImmutable($broadcast->starttime);
-        $endDate = ($broadcast->enddate == null) ? $now : $broadcast->enddate;
-        $endDate = $endDate->setTime($startTijd->format('H'), $startTijd->format('i'), $startTijd->format('s'));
-        $endDateWeekday = $endDate->format('N');
-
-        // Zoek de laatste uitzending voor de einddatum (of voor het huidige tijdstip), op de juiste weekdag
-        while($endDateWeekday != $broadcast->startday) {
-          $endDate = $endDate->sub($ONE_DAY);
-          if(--$endDateWeekday < 0) { $endDateWeekday += 7; }
-        }
-
-        $eindTijd = new \DateTimeImmutable($broadcast->endtime);
-        $endOfBroadcast = $endDate->setTime($eindTijd->format('H'), $eindTijd->format('i'), $eindTijd->format('s'));
-        if($endOfBroadcast < $endDate) { $endOfBroadcast = $endOfBroadcast->add($ONE_DAY); }
-
-        if($isInProgress = (($endDate <= $now) && ($endOfBroadcast > $now))) {
-          $isCurrent = true;
-        }
-
-        // Als de uitzending niet al afgelopen is, telt hij als volgende.
-        // Dit gebeurt als de uitzending later vandaag is of nu loopt.
-        if($endOfBroadcast >= $now) {
-          $endDate = $endDate->sub($ONE_WEEK);
-          $endOfBroadcast = $endOfBroadcast->sub($ONE_WEEK);
-        }
-
-        if((($broadcast->startdate == null) || ($broadcast->startdate <= $endDate)) 
-         && (($broadcast->enddate == null) || ($broadcast->enddate >= $endDate->setTime(0,0,0)))) {
-          $recent[] = ['time' => $endDate, 'suffix' => $broadcast->suffix, 'isSpecial' => ($broadcast->priority < 2)];
-        }
-
-
-        $previous = $endDate->sub($ONE_WEEK);       
-        if((($broadcast->startdate == null) || ($broadcast->startdate <= $previous)) 
-         && (($broadcast->enddate == null) || ($broadcast->enddate >= $previous->setTime(0,0,0)))) {
-          $recent[] = ['time' => $previous, 'suffix' => $broadcast->suffix, 'isSpecial' => ($broadcast->priority < 2)];
-        }
-  
-        $following = $endDate->add($ONE_WEEK);
-        if(($broadcast->enddate == null) || ($broadcast->enddate->setTime(23,59,59) > $following)) {
-          if($following < $now) { 
-            $isCurrent = true;
-          }
-
-          $next[] = ['time' => $following, 'suffix' => $broadcast->suffix, 'isSpecial' => ($broadcast->priority < 2)];
-        }
-      }
-
-      sort($next);
-      rsort($recent);
-      return ['recent' => array_reverse(array_splice($recent, 0, 2)), 'next' => count($next) ? $next[0] : null, 'iscurrent' => $isCurrent];
-    }
-
     /**
     * Programmas nu en straks (24 uur vooruit)
     */
@@ -153,109 +226,4 @@ QUERY
 
         return response()->json($this->createSchedule($start, $einde));
     }
-   
-    private function createSchedule($start, $einde) {
-        if(!defined('PROGRAMMA_START')) {
-          define('PROGRAMMA_START', 1);
-          define('PROGRAMMA_EINDE', -1);
-  
-          define('PW_TIJDSTIP', 0);
-          define('PW_TYPE', 1);
-          define('PW_PROGRAMMA', 2);
-        }
- 
-        $oneWeek = \DateInterval::createFromDateString('1 week');
-
-        $programmas = app('db')->select(self::$SCHEDULE_SQL,
-          ['enddate' => $einde->format('Y-m-d'), 'startdate' => $start->format('Y-m-d')]);
-        $programmaInfo = [];
-
-        // Maak een lijstje van alle start en eindtijden en welk programma dan begint/eindigt
-        $startEinde = [];
-        $startMaandag = $start->modify('Monday this week');
-        foreach($programmas as $programma) {
-          if($programma->suffix) $programma->name .= ' ' . $programma->suffix;
-          $programmaInfo[$programma->scheduleid] = new \Model\Program($programma);
-
-          $programmaStart = $startMaandag->add(\DateInterval::createFromDateString(($programma->startday - 1) % 7 . ' days'));
-          $programmaEinde = $startMaandag->add(\DateInterval::createFromDateString(($programma->endday - 1) % 7 . ' days'));
-
-          $startTijd = new \DateTime($programma->starttime);
-          $eindTijd = new \DateTime($programma->endtime);
-
-          $programmaStart = $programmaStart->setTime($startTijd->format('H'), $startTijd->format('i'), $startTijd->format('s'));
-          $programmaEinde = $programmaEinde->setTime($eindTijd->format('H'), $eindTijd->format('i'), $eindTijd->format('s'));
-          
-          if($programmaEinde <= $programmaStart) { 
-            $programmaEinde = $programmaEinde->add($oneWeek);
-          }
-
-          if($programmaEinde < $start) {
-            $programmaStart = $programmaStart->add($oneWeek);
-            $programmaEinde = $programmaEinde->add($oneWeek);
-          }
-
-          while($programmaStart < $einde) {
-            if((($programma->startdate == null) || ($programmaStart >= new \DateTime($programma->startdate)))
-              && (($programma->enddate == null) || ($programmaStart <= (new \DateTimeImmutable($programma->enddate))->setTime(23,59,59))) 
-              && (($programmaEinde >= $start) && ($programmaStart <= $einde)))
-            {
-              $startEinde[] = [$programmaStart, PROGRAMMA_START, $programma->scheduleid];
-              $startEinde[] = [$programmaEinde, PROGRAMMA_EINDE, $programma->scheduleid];
-            } 
-
-            $programmaStart = $programmaStart->add($oneWeek);
-            $programmaEinde = $programmaEinde->add($oneWeek);
-          }
-        }
-
-        array_multisort($startEinde);
-
-        $actieveProgrammas = [null, null, null, null];
-        $schema = [];
-        $fouten = [];
-        $index = -1;
-        foreach($startEinde as $programmaWissel) {
-          $scheduleId = $programmaWissel[PW_PROGRAMMA];
-          $programma = $programmaInfo[$scheduleId];
-          $tijdstip = $programmaWissel[PW_TIJDSTIP];
-          if($programmaWissel[PW_TIJDSTIP] < $start) { $tijdstip = $start; }
-          if($programmaWissel[PW_TIJDSTIP] > $einde) { $tijdstip = $einde; }
-          if($tijdstip == $einde) { break; }
-
-          if($programmaWissel[PW_TYPE] == PROGRAMMA_START) {
-            if($actieveProgrammas[$programma->priority] != null) { 
-              $fouten[] = [$tijdstip, "Begin van {$programma->name} maar {$actieveProgrammas[$programma->priority]->name} is nog actief."]; 
-            } 
-
-            $actieveProgrammas[$programma->priority] = $scheduleId;
-            for($prio = $programma->priority; $prio >= 0; --$prio) { 
-              if($actieveProgrammas[$prio] != null) {
-                if(($index == -1) || ($schema[$index]['starttime'] != $tijdstip)) { $index++; }
-                $schema[$index] = ['starttime' => $tijdstip, 'endtime' => null, 'program' => $programmaInfo[$actieveProgrammas[$prio]]];
-                break;
-              }
-            }
-          } else /*if($programmaWissel[PW_TYPE] == PROGRAMMA_EINDE)*/ {
-            $actieveProgrammas[$programma->priority] = null;
-            if(($index == -1) || ($schema[$index]['program'] != null)) { $index++; }
-            $schema[$index] = ['starttime' => $tijdstip, 'program' => null];
-            for($prio = $programma->priority; $prio < count($actieveProgrammas); ++$prio) { 
-              if($actieveProgrammas[$prio] != null) {
-                $schema[$index] = ['starttime' => $tijdstip, 'endtime' => null, 'program' => $programmaInfo[$actieveProgrammas[$prio]]];
-                break;
-              }
-            }
-          }
-        }
-
-        for($i = 1; $i <= count($schema); $i++) {
-          $eindTijd = ($i == count($schema)) ? $einde : $schema[$i]['starttime'];
-          $schema[$i - 1]['endtime'] = $eindTijd;
-          //$programma = $schema[$i-1]['program'];
-          //print $schema[$i-1]['starttime']->format('D d-m-Y, H:i:s') . " - " . $eindTijd->format('D d-m-Y, H:i:s') . ": " . ($programma != null ? $programma->name : "NULL") . "\n";
-        }
-
-        return ['startdate' => $start, 'enddate' => $einde, 'schedule' => $schema, 'errors' => $fouten];
-     }
 }
diff --git a/api/routes/web.php b/api/routes/web.php
index 9222f13..4919dde 100644
--- a/api/routes/web.php
+++ b/api/routes/web.php
@@ -32,7 +32,9 @@ $app->get('podcast/stream/{id:\d+}/{title}', 'PodcastController@stream' );
 
 $app->get('programma/schema/nustraks', 'ProgramController@comingup' );
 $app->get('programma/schema/week[/{shiftWeeks:-?\d+}]', 'ProgramController@schedule' );
-$app->get('/programma/details/{id:\d+}', 'ProgramController@details' );
+$app->get('programma/details/{id:\d+}', 'ProgramController@details' );
+
+$app->get('programma/schema/test/{from}/{to}', 'ProgramController@testSchedule' );
 
 // live/onair
 // live/stream
diff --git a/common/classes/Program.php b/common/classes/Program.php
index 358bba4..3878af3 100644
--- a/common/classes/Program.php
+++ b/common/classes/Program.php
@@ -9,12 +9,16 @@ class Program extends Model {
   public $email;
   public $priority;
 
-  // TODO: Implementeren
   public $hosts;
   public $schedule;
 
   public function __construct($data) {
     parent::__construct($data);
+
+    if(isset($data->suffix) && $data->suffix) { 
+      $this->name .= ' ' . $data->suffix;
+    } 
+
     if($this->schedule && $this->schedule->next && $this->schedule->next->time) {
       parent::ConvertToDateTime($this->schedule->next->time);
     }
@@ -31,4 +35,8 @@ class Program extends Model {
 
     $this->url = "/{$this->id}/" . parent::url_slug($this->name);
   }
+ 
+  public function isSpecial() {
+    return ($this->priority < 2);
+  }
 }