class Schedule(ImageContent):
"""A database-backed schedule determining which images to show at request
time and when to wake up from sleep for the next request.
The schedule is a list of maps, each containing:
'name': A human-readable name for this entry.
'start': A cron expression for the start time of this entry. (The end time
is the start time of the next closest entry in time.) The cron
expression syntax additionally supports the keywords 'sunrise' and
'sunset' instead of hours and minutes, e.g. 'sunrise * * *'.
'image': The kind of image to show when this entry is active. Valid kinds
are 'artwork', 'city', 'commute', 'calendar', and 'everyone'.
"""
def __init__(self, geocoder):
self.local_time = LocalTime(geocoder)
self.sun = Sun(geocoder)
self.artwork = Artwork()
self.city = City(geocoder)
self.commute = Commute(geocoder)
self.calendar = GoogleCalendar(geocoder)
self.everyone = Everyone(geocoder)
def _next(self, cron, after, user):
"""Finds the next time matching the cron expression."""
try:
cron = self.sun.rewrite_cron(cron, after, user)
except DataError as e:
raise ContentError(e)
try:
return croniter(cron, after).get_next(datetime)
except ValueError as e:
raise ContentError(e)
def _image(self, kind, user):
"""Creates an image based on the kind."""
if kind == 'artwork':
content = self.artwork
elif kind == 'city':
content = self.city
elif kind == 'commute':
content = self.commute
elif kind == 'calendar':
content = self.calendar
elif kind == 'everyone':
content = self.everyone
else:
error('Unknown image kind: %s' % kind)
return None
return content.image(user)
def image(self, user):
"""Generates the current image based on the schedule."""
# Find the current schedule entry by parsing the cron expressions.
try:
time = self.local_time.now(user)
except DataError as e:
raise ContentError(e)
today = time.replace(hour=0, minute=0, second=0, microsecond=0)
while True:
entries = [(self._next(entry['start'], today, user), entry)
for entry in user.get('schedule')]
if not entries:
raise ContentError('Empty schedule')
past_entries = list(filter(lambda x: x[0] <= time, entries))
# Use the most recent past entry.
if past_entries:
latest_datetime, latest_entry = max(past_entries,
key=lambda x: x[0])
break
# If there were no past entries, try the previous day.
today -= timedelta(days=1)
# Generate the image from the current schedule entry.
info('Using image from schedule entry: %s (%s, %s)' %
(latest_entry['name'], latest_entry['start'],
latest_datetime.strftime('%A %B %d %Y %H:%M:%S %Z')))
image = self._image(latest_entry['image'], user)
return image
def delay(self, user):
"""Calculates the delay in milliseconds to the next schedule entry."""
# Find the next schedule entry by parsing the cron expressions.
try:
time = self.local_time.now(user)
except DataError as e:
raise ContentError(e)
entries = [(self._next(entry['start'], time, user), entry)
for entry in user.get('schedule')]
if not entries:
raise ContentError('Empty schedule')
next_datetime, next_entry = min(entries, key=lambda x: x[0])
# Calculate the delay in milliseconds.
seconds = (next_datetime - time).total_seconds()
seconds += DELAY_BUFFER_S
milliseconds = int(seconds * 1000)
info('Using time from schedule entry: %s (%s, %s, in %d ms)' %
(next_entry['name'], next_entry['start'],
next_datetime.strftime('%A %B %d %Y %H:%M:%S %Z'), milliseconds))
return milliseconds
class Schedule(ImageContent):
"""User schedule processing.
A database-backed schedule determining which images to show at request
time and when to wake up from sleep for the next request.
The schedule is a list of maps, each containing:
'name': A human-readable name for this entry.
'start': A cron expression for the start time of this entry. (The end time
is the start time of the next closest entry in time.) The cron
expression syntax additionally supports the keywords 'sunrise' and
'sunset' instead of hours and minutes, e.g. 'sunrise * * *'.
'image': The kind of image to show when this entry is active. Valid kinds
are 'artwork', 'city', 'commute', 'calendar', and 'everyone'.
"""
def __init__(self, geocoder):
"""Schedule constructor.
Args:
geocoder (geocoder.Geocoder): Used to localize user specified locations
"""
self._local_time = LocalTime(geocoder)
self._sun = Sun(geocoder)
self._artwork = Artwork()
self._city = City(geocoder)
self._commute = Commute(geocoder)
self._calendar = GoogleCalendar(geocoder)
self._everyone = Everyone(geocoder)
def _next(self, cron, after, user):
"""Find the next time matching the cron expression."""
try:
cron = self._sun.rewrite_cron(cron, after, user)
except DataError as e:
raise ContentError(e)
try:
return croniter(cron, after).get_next(datetime)
except ValueError as e:
raise ContentError(e)
def _previous(self, cron, before, user):
"""Find the previous time matching the cron expression."""
try:
cron = self._sun.rewrite_cron(cron, before, user)
except DataError as e:
raise ContentError(e)
try:
return croniter(cron, before).get_prev(datetime)
except ValueError as e:
raise ContentError(e)
def _image(self, kind, user, width, height):
"""Create an image based on the kind."""
if kind == 'artwork':
content = self._artwork
elif kind == 'city':
content = self._city
elif kind == 'commute':
content = self._commute
elif kind == 'calendar':
content = self._calendar
elif kind == 'everyone':
content = self._everyone
else:
error('Unknown image kind: %s' % kind)
return None
return content.image(user, width, height)
def image(self, user, width, height):
"""Generate the current image based on the schedule."""
# Find the current schedule entry by parsing the cron expressions.
try:
time = self._local_time.now(user)
except DataError as e:
raise ContentError(e)
entries = [(self._previous(entry['start'], time, user), entry)
for entry in user.get('schedule')]
if not entries:
raise ContentError('Empty schedule')
# Use the most recent past entry.
latest_datetime, latest_entry = max(entries, key=lambda x: x[0])
# Generate the image from the current schedule entry.
info('Using image from schedule entry: %s (%s, %s)' %
(latest_entry['name'], latest_entry['start'],
latest_datetime.strftime('%A %B %d %Y %H:%M:%S %Z')))
image = self._image(latest_entry['image'], user, width, height)
return image
def delay(self, user):
"""Calculate the delay in milliseconds to the next schedule entry."""
# Find the next schedule entry by parsing the cron expressions.
try:
time = self._local_time.now(user)
except DataError as e:
raise ContentError(e)
entries = [(self._next(entry['start'], time, user), entry)
for entry in user.get('schedule')]
if not entries:
raise ContentError('Empty schedule')
next_datetime, next_entry = min(entries, key=lambda x: x[0])
# Calculate the delay in milliseconds.
seconds = (next_datetime - time).total_seconds()
seconds += DELAY_BUFFER_S
milliseconds = int(seconds * 1000)
info('Using time from schedule entry: %s (%s, %s, in %d ms)' %
(next_entry['name'], next_entry['start'],
next_datetime.strftime('%A %B %d %Y %H:%M:%S %Z'), milliseconds))
return milliseconds
def empty_timeline(self):
"""Generate an empty timeline image."""
image = Image.new(mode='RGB',
size=(TIMELINE_WIDTH, TIMELINE_HEIGHT),
color=TIMELINE_BACKGROUND)
draw = Draw(image)
# Draw each day of the week.
num_days = len(day_abbr)
for day_index in range(num_days):
x = TIMELINE_DRAW_WIDTH * day_index / num_days
# Draw a dashed vertical line.
for y in range(0, TIMELINE_HEIGHT, 2 * TIMELINE_LINE_DASH):
draw.line([(x, y), (x, y + TIMELINE_LINE_DASH - 1)],
fill=TIMELINE_FOREGROUND,
width=TIMELINE_LINE_WIDTH)
# Draw the abbreviated day name.
name = day_abbr[day_index]
day_x = x + TIMELINE_DRAW_WIDTH / num_days / 2
day_y = TIMELINE_HEIGHT - SCREENSTAR_SMALL_REGULAR['height']
draw_text(name,
SCREENSTAR_SMALL_REGULAR,
TIMELINE_FOREGROUND,
xy=(day_x, day_y),
anchor=None,
box_color=None,
box_padding=0,
border_color=None,
border_width=0,
image=image,
draw=draw)
# Draw another dashed line at the end.
for y in range(0, TIMELINE_HEIGHT, 2 * TIMELINE_LINE_DASH):
draw.line([(TIMELINE_DRAW_WIDTH, y),
(TIMELINE_DRAW_WIDTH, y + TIMELINE_LINE_DASH - 1)],
fill=TIMELINE_FOREGROUND,
width=TIMELINE_LINE_WIDTH)
return image
def timeline(self, user):
"""Generate a timeline image of the schedule for settings."""
image = self.empty_timeline()
draw = Draw(image)
# Find the user or return the empty timeline.
try:
now = self._local_time.now(user)
except DataError as e:
return image
# Start the timeline with the most recent beginning of the week.
start = now.replace(hour=0, minute=0, second=0)
start -= timedelta(days=start.weekday())
stop = start + timedelta(weeks=1)
start_timestamp = datetime.timestamp(start)
stop_timestamp = datetime.timestamp(stop)
timestamp_span = stop_timestamp - start_timestamp
# Draw a dashed line in highlight color at the current time.
now_timestamp = datetime.timestamp(now)
now_x = TIMELINE_DRAW_WIDTH * (now_timestamp -
start_timestamp) / timestamp_span
for y in range(0, TIMELINE_HEIGHT, 2 * TIMELINE_LINE_DASH):
draw.line([(now_x, y), (now_x, y + TIMELINE_LINE_DASH - 1)],
fill=TIMELINE_HIGHLIGHT,
width=TIMELINE_LINE_WIDTH)
# Generate the schedule throughout the week.
entries = user.get('schedule')
if not entries:
# Empty timeline.
return image
for i in range(len(entries)):
entries[i]['index'] = i
time = start
while time < stop:
# Find the next entry.
next_entries = [(self._next(entry['start'], time,
user), entry['index'], entry)
for entry in entries]
next_datetime, next_index, next_entry = min(next_entries,
key=lambda x: x[0])
# Draw the entry's index and a vertical line, with a tilde to mark
# the variable sunrise and sunset times.
timestamp = datetime.timestamp(next_datetime)
x = TIMELINE_DRAW_WIDTH * (timestamp -
start_timestamp) / timestamp_span
y = TIMELINE_HEIGHT / 2
text = str(next_index + 1)
next_entry_start = next_entry['start']
if 'sunrise' in next_entry_start or 'sunset' in next_entry_start:
text = '~' + text
box = draw_text(text,
SCREENSTAR_SMALL_REGULAR,
TIMELINE_FOREGROUND,
xy=(x, y),
anchor=None,
box_color=None,
box_padding=4,
border_color=None,
border_width=0,
image=image,
draw=draw)
draw.line([(x, 0), (x, box[1])], fill=TIMELINE_FOREGROUND, width=1)
# Jump to the next entry.
time = next_datetime
return image