timetable.py

 from server import *
-from datetime import time
 
-@register_navbar('personalisierter Drehplan', icon='calendar', userendpoint=True, endpoint='timetable_user')
-@register_navbar('Drehplan', icon='calendar')
-@app.route('/internal/timetable')
-@app.route('/internal/user/<int:user>/timetable', endpoint='timetable_user')
-@mod_required
-def timetable(user=None):
-	if 'kw' not in request.args:
-		if 'date' in request.args:
-			thisweekmonday = datetime.now()
-			thisweekmonday -= timedelta(days=thisweekmonday.weekday())
+def get_monday(day):
+	return day-timedelta(days=day.weekday())
 
+def get_week_offset(value):
+	if value is None:
+		return 0
+	day = None
+	for pattern in ['%d-%m-%Y-1', '%Y-W%W-%w']:
 		try:
-				datesweekmonday = datetime.strptime(request.args['date'], '%d-%m-%Y')
-			except ValueError:
-				datesweekmonday = None
-			if not datesweekmonday:
-				try:
-					datesweekmonday = datetime.strptime(request.args['date'] + '-1', "%Y-W%W-%w")
+			day = datetime.strptime(value+'-1', pattern)
 		except ValueError:
-					datesweekmonday = None
+			pass
+		if day is not None:
+			break
+	if day is None:
+		return 0
+	return int((get_monday(day) - get_monday(datetime.now())).days/7)
 
-			if not datesweekmonday:
-				kw = 0
-			else:
-				datesweekmonday -= timedelta(days=datesweekmonday.weekday())
-				kw = int((datesweekmonday.date() - thisweekmonday.date()).days/7)
-		else:
-			kw=0
-	else:
-		kw=int(request.args['kw'])
-	try:
-		start = date.today() - timedelta(days=date.today().weekday() -7*kw)
-	except:
-		start = date.today() - timedelta(days=date.today().weekday())
-	weekofyear = '{}-W{:02d}'.format(datetime.today().year, datetime.today().isocalendar()[1])
-	days = [{'date': start, 'lectures': [], 'atonce':0, 'index': 0 }]
-	earlieststart=time(23,59)
-	latestend=time(0,0)
-	for i in range(1,7):
-		days.append({'date': days[i-1]['date'] + timedelta(days=1), 'atonce':0, 'index': i, 'lectures':[] })
-	for i in days:
-		# date and times are burning in sqlite
-		s = datetime.combine(i['date'],time(0,0))
-		e = datetime.combine(i['date'],time(23,59))
-		i['lectures'] = []
-		for l in query ('''
-					SELECT lectures.*, courses.short, "course" AS sep, courses.*
+def query_lectures_on_day(start, end):
+	# What we want to match:
+	#  lecture.time <= end AND lecture.time+lecture.duration >= start
+	# But there is no SQL statement that does this and is compatible with both sqlite
+	# and mysql, so we approximate the "lecture.time+lecture.duration" part
+	rows = query('''SELECT lectures.*, courses.short, \'course\' AS sep, courses.*
 		FROM lectures 
 		JOIN courses ON (lectures.course_id = courses.id) 
-					WHERE time < ? AND time > ? AND NOT norecording AND NOT external
-					ORDER BY time ASC''', i['date']+timedelta(weeks=2), i['date']-timedelta(weeks=2)):
-			# we can not use the where clause of sql to match against the time, because sqlite and mysql use a different syntax -.-
-			# we still use it to only get the lectures for a 3 week periode
-			if not l['time']:
-				l['time'] = datetime.fromtimestamp(0)
-			if ((l['time'] < e) and (l['time'] > s)) or ((l['time'] + timedelta(minutes=l['duration']) < e) and (l['time'] + timedelta(minutes=l['duration'])> s)):
-				# filter on responsible user if a user parameter was given
-				l['responsible'] = query('''SELECT users.*
-						FROM responsible
-						JOIN users ON (responsible.user_id = users.id AND responsible.course_id = ?)
-						ORDER BY users.realname ASC''', l['course_id'])
-				if len(l['responsible']) == 0:
-					l['responsible'] = [{"realname": "Niemand", "id": -1}]
-				if not user or user in [ r['id'] for r in l['responsible'] ]:
-					i['lectures'].append(l)
+		WHERE time <= ? AND time > ?
+		ORDER BY time ASC''', end, start-timedelta(weeks=2))
+	lectures = []
+	for lecture in rows:
+		if lecture['time']+timedelta(minutes=lecture['duration']) >= start:
+			lectures.append(lecture)
+	return lectures
 
-				oldtime = l['time']
-				l['time'] = max(s,l['time'])
-				l['duration'] = ( min(e,oldtime + timedelta(minutes=l['duration'])) - l['time'] ).total_seconds()/60
-		# sweepline to find out how many lectures overlap
-		maxcol=0;
-		curcol=0;
-		freecol=[];
-		for l in i['lectures']:
-			# who the hell inserts lectures with zero length?!?!?
-			l['time_end'] = l['time']+timedelta(minutes=max(l['duration'],1))
-		# create sweepline input array
-		sweeplinetupels = [(l['time'],True,l) for l in i['lectures']]
-		sweeplinetupels += [(l['time_end'],False,l) for l in i['lectures']]
-		tmp = []
-		for x in sweeplinetupels:
-			unique = True
-			for y in tmp:
-				if x[0] == y[0] and x[1] == y[1] and x[2]['short'] == y[2]['short']:
-					unique = False
-			if unique:
-				tmp.append(x)
+'''Use a sweepline algorithm to find overlapping lectures
 
-		sweeplinetupels = sorted(tmp, key=lambda t:(t[0],t[1]))
-		for l in sweeplinetupels:
-			if l[1]:
+For each day the item 'maxcol' will be the number of columns required to display
+the overlapping lectures. For each lecture the item 'timetable_col' will be the
+index of the column the lecture is going to be rendered in.'''
+def timetable_sweepline(days):
+	earliest_start = time(23, 59)
+	latest_end = time(0, 0)
+	for day in days:
+		sweeplinetupels = [(lecture['time'].time(), True, lecture) for lecture in day['lectures']]
+		sweeplinetupels += [(lecture['time_end'].time(), False, lecture) for lecture in day['lectures']]
+		maxcol = 0
+		curcol = 0
+		freecol = []
+		sweeplinetupels.sort(key=lambda row: row[:2])
+		for timestamp, is_start, lecture in sweeplinetupels:
+			if is_start:
 				curcol += 1
-				if curcol > maxcol:
-					maxcol = curcol
-				if len(freecol) == 0:
-					freecol.append(maxcol)
-				l[2]['timetable_col'] = freecol.pop()
-				if earlieststart > l[0].time():
-					earlieststart = l[0].time()
+				maxcol = max(maxcol, curcol)
+				if freecol:
+					lecture['timetable_col'] = freecol.pop()
+				else:
+					lecture['timetable_col'] = maxcol
+				earliest_start = min(earliest_start, timestamp)
 			else:
 				curcol -= 1
-				freecol.append(l[2]['timetable_col'])
-				if latestend < l[0].time():
-					latestend = l[0].time()
-		i['maxcol'] = max(maxcol,1)
-	times=[]
-	s = min(earlieststart,time(8,0))
-	e = max(latestend,time(19,0))
-	for i in range(s.hour*4,min(int((60*e.hour/15)/4)*4+5,24*4)):
-		t = i*15
-		times.append(time(int(t/60),t%60))
-	return render_template('timetable.html',days=days,times=times,kw=kw, weekofyear=weekofyear, user=query('SELECT * FROM users WHERE id = ?', user)[0] if user else None)
+				freecol.append(lecture['timetable_col'])
+				latest_end = max(latest_end, timestamp)
+		day['maxcol'] = max(maxcol, 1)
+	return earliest_start, latest_end
+
+@register_navbar('personalisierter Drehplan', icon='calendar', userendpoint=True, endpoint='timetable_user')
+@register_navbar('Drehplan', icon='calendar')
+@app.route('/internal/timetable')
+@app.route('/internal/user/<int:user>/timetable', endpoint='timetable_user')
+@mod_required
+def timetable(user=None):
+	if 'kw' in request.args:
+		week_offset = int(request.args['kw'])
+	else:
+		week_offset = get_week_offset(request.args.get('date', None))
+	start_day = date.today() - timedelta(days=date.today().weekday() - 7*week_offset)
+	days = [{'date': start_day, 'lectures': [], 'atonce': 0, 'index': 0}]
+	for i in range(1, 7):
+		days.append({'date': days[i-1]['date'] + timedelta(days=1), 'atonce': 0, 'index': i, 'lectures': []})
+	for day in days:
+		start = datetime.combine(day['date'], time(0, 0))
+		end = datetime.combine(day['date'], time(23, 59))
+		day['lectures'] = []
+		for lecture in query_lectures_on_day(start, end):
+			lecture['time_end'] = lecture['time']+timedelta(minutes=lecture['duration'])
+			# "Crop" lecture's timespan to start/end of day
+			lecture['time'] = max(start, lecture['time'])
+			lecture['time_end'] = min(end, lecture['time_end'])
+			# Ensure length > 0
+			lecture['time_end'] = max(lecture['time_end'], lecture['time']+timedelta(minutes=1))
+			lecture['duration'] = int((lecture['time_end'] - lecture['time']).total_seconds()/60)
+			# Filter on responsible user if a user parameter was given
+			lecture['responsible'] = query('''SELECT users.*
+					FROM responsible
+					JOIN users ON (responsible.user_id = users.id AND responsible.course_id = ?)
+					ORDER BY users.realname ASC''', lecture['course_id'])
+			if len(lecture['responsible']) == 0:
+				lecture['responsible'] = [{"realname": "Niemand", "id": -1}]
+			if not user or user in [r['id'] for r in lecture['responsible']]:
+				day['lectures'].append(lecture)
+	earliest_start, latest_end = timetable_sweepline(days)
+	start = min(earliest_start, time(8, 0))
+	end = max(latest_end, time(19, 0))
+	blocks = []
+	for i in range(start.hour*4, min(int((60*end.hour/15)/4)*4+5, 24*4)):
+		timestamp = i*15
+		blocks.append(time(int(timestamp/60), timestamp%60))
+	weekofyear = '{}-W{:02d}'.format(datetime.today().year, datetime.today().isocalendar()[1])
+	return render_template('timetable.html',
+			days=days,
+			blocks=blocks,
+			kw=week_offset,
+			weekofyear=weekofyear,
+			user=query('SELECT * FROM users WHERE id = ?', user)[0] if user else None)