diff --git a/Manifest.in b/Manifest.in
deleted file mode 100755
index 1001e08..0000000
--- a/Manifest.in
+++ /dev/null
@@ -1,3 +0,0 @@
-include LICENSE
-include README.md
-
diff --git a/__init__.py b/__init__.py
deleted file mode 100755
index e69de29..0000000
diff --git a/aircox/admin/__init__.py b/aircox/admin/__init__.py
index 1954e33..f7fcc8d 100644
--- a/aircox/admin/__init__.py
+++ b/aircox/admin/__init__.py
@@ -22,7 +22,7 @@ class StationAdmin(admin.ModelAdmin):
 
 @admin.register(Log)
 class LogAdmin(admin.ModelAdmin):
-    list_display = ['id', 'date', 'station', 'source', 'type', 'diffusion', 'sound', 'track']
+    list_display = ['id', 'date', 'station', 'source', 'type', 'comment']
     list_filter = ['date', 'source', 'station']
 
 
diff --git a/aircox/admin/__pycache__/__init__.cpython-37.pyc b/aircox/admin/__pycache__/__init__.cpython-37.pyc
index 70c1708..71693ed 100644
Binary files a/aircox/admin/__pycache__/__init__.cpython-37.pyc and b/aircox/admin/__pycache__/__init__.cpython-37.pyc differ
diff --git a/aircox/controllers.py b/aircox/controllers.py
index f0b16d6..cf8b7cb 100755
--- a/aircox/controllers.py
+++ b/aircox/controllers.py
@@ -17,6 +17,10 @@ from .models import Port, Station, Sound
 from .connector import Connector
 
 
+# FIXME liquidsoap does not manage timezones -- we have to convert
+#       'on_air' metadata we get from it into utc one in order to work
+#       correctly.
+
 local_tz = tzlocal.get_localzone()
 logger = logging.getLogger('aircox')
 
@@ -32,7 +36,11 @@ class Streamer:
     sources = None
     """ List of all monitored sources """
     source = None
-    """ Current on air source """
+    """ Current source being played on air """
+    # note: we disable on_air rids since we don't have use of it for the
+    # moment
+    # on_air = None
+    # """ On-air request ids (rid) """
 
     def __init__(self, station):
         self.station = station
@@ -46,6 +54,27 @@ class Streamer:
         """ Path to Unix socket file """
         return self.connector.address
 
+    @property
+    def is_ready(self):
+        """
+        If external program is ready to use, returns True
+        """
+        return self.send('list') != ''
+
+    @property
+    def is_running(self):
+        if self.process is None:
+            return False
+
+        returncode = self.process.poll()
+        if returncode is None:
+            return True
+
+        self.process = None
+        logger.debug('process died with return code %s' % returncode)
+        return False
+
+    # FIXME: is it really needed as property?
     @property
     def inputs(self):
         """ Return input ports of the station """
@@ -62,13 +91,6 @@ class Streamer:
             active=True,
         )
 
-    @property
-    def is_ready(self):
-        """
-        If external program is ready to use, returns True
-        """
-        return self.send('list') != ''
-
     # Sources and config ###############################################
     def send(self, *args, **kwargs):
         return self.connector.send(*args, **kwargs) or ''
@@ -98,26 +120,27 @@ class Streamer:
 
     def sync(self):
         """ Sync all sources. """
+        if self.process is None:
+            return
+
         for source in self.sources:
             source.sync()
 
     def fetch(self):
         """ Fetch data from liquidsoap """
+        if self.process is None:
+            return
+
         for source in self.sources:
             source.fetch()
 
-        rid = self.send('request.on_air').split(' ')
-        if rid:
-            rid = rid[-1]
-            # data = self._send('request.metadata ', rid, parse=True)
-            # if not data:
-            #     return
-            pred = lambda s: s.rid == rid
-        else:
-            pred = lambda s: s.is_playing
+        # request.on_air is not ordered: we need to do it manually
+        if self.dealer.is_playing:
+            self.source = self.dealer
+            return
 
-        self.source = next((source for source in self.sources if pred(source)),
-                           self.source)
+        self.source = next((source for source in self.sources
+                           if source.is_playing), None)
 
     # Process ##########################################################
     def get_process_args(self):
@@ -152,10 +175,8 @@ class Streamer:
 
     def kill_process(self):
         if self.process:
-            logger.info("kill process {pid}: {info}".format(
-                pid=self.process.pid,
-                info=' '.join(self.get_process_args())
-            ))
+            logger.debug("kill process %s: %s", self.process.pid,
+                         ' '.join(self.get_process_args()))
             self.process.kill()
             self.process = None
 
@@ -170,12 +191,19 @@ class Streamer:
 
 class Source:
     controller = None
+    """ parent controller """
     id = None
-
+    """ source id """
     uri = ''
+    """ source uri """
     rid = None
+    """ request id """
     air_time = None
+    """ on air time """
     status = None
+    """ source status """
+    remaining = 0.0
+    """ remaining time """
 
     @property
     def station(self):
@@ -185,6 +213,10 @@ class Source:
     def is_playing(self):
         return self.status == 'playing'
 
+    #@property
+    #def is_on_air(self):
+    #    return self.rid is not None and self.rid in self.controller.on_air
+
     def __init__(self, controller, id=None):
         self.controller = controller
         self.id = id
@@ -194,14 +226,17 @@ class Source:
         pass
 
     def fetch(self):
+        data = self.controller.send(self.id, '.remaining')
+        self.remaining = float(data)
+
         data = self.controller.send(self.id, '.get', parse=True)
         self.on_metadata(data if data and isinstance(data, dict) else {})
 
     def on_metadata(self, data):
         """ Update source info from provided request metadata """
-        self.rid = data.get('rid')
-        self.uri = data.get('initial_uri')
-        self.status = data.get('status')
+        self.rid = data.get('rid') or None
+        self.uri = data.get('initial_uri') or None
+        self.status = data.get('status') or None
 
         air_time = data.get('on_air')
         if air_time:
@@ -277,8 +312,17 @@ class PlaylistSource(Source):
 
 
 class QueueSource(Source):
-    def queue(self, *paths):
+    queue = None
+    """ Source's queue (excluded on_air request) """
+
+    def append(self, *paths):
         """ Add the provided paths to source's play queue """
         for path in paths:
-            print(self.controller.send(self.id, '_queue.push ', path))
+            self.controller.send(self.id, '_queue.push ', path)
+
+    def fetch(self):
+        super().fetch()
+        queue = self.controller.send(self.id, '_queue.queue').split(' ')
+        self.queue = queue
+
 
diff --git a/aircox/management/commands/archiver.py b/aircox/management/commands/archiver.py
index 06893cf..b652af5 100644
--- a/aircox/management/commands/archiver.py
+++ b/aircox/management/commands/archiver.py
@@ -12,7 +12,7 @@ from django.utils import timezone as tz
 import aircox.settings as settings
 from aircox.models import Log, Station
 
-logger = logging.getLogger('aircox.tools')
+logger = logging.getLogger('aircox.commands')
 
 
 class Command (BaseCommand):
diff --git a/aircox/management/commands/diffusions.py b/aircox/management/commands/diffusions.py
index f75fbd3..0b8085c 100755
--- a/aircox/management/commands/diffusions.py
+++ b/aircox/management/commands/diffusions.py
@@ -25,7 +25,7 @@ from django.utils import timezone as tz
 
 from aircox.models import Schedule, Diffusion
 
-logger = logging.getLogger('aircox.tools')
+logger = logging.getLogger('aircox.commands')
 
 
 class Actions:
diff --git a/aircox/management/commands/import_playlist.py b/aircox/management/commands/import_playlist.py
index 011e221..122aa20 100755
--- a/aircox/management/commands/import_playlist.py
+++ b/aircox/management/commands/import_playlist.py
@@ -23,7 +23,7 @@ from aircox.models import *
 
 __doc__ = __doc__.format(settings=settings)
 
-logger = logging.getLogger('aircox.tools')
+logger = logging.getLogger('aircox.commands')
 
 
 class PlaylistImport:
diff --git a/aircox/management/commands/sounds_monitor.py b/aircox/management/commands/sounds_monitor.py
index 422d08d..2767eaa 100755
--- a/aircox/management/commands/sounds_monitor.py
+++ b/aircox/management/commands/sounds_monitor.py
@@ -42,7 +42,7 @@ from aircox import settings, utils
 from aircox.models import Diffusion, Program, Sound
 from .import_playlist import PlaylistImport
 
-logger = logging.getLogger('aircox.tools')
+logger = logging.getLogger('aircox.commands')
 
 
 sound_path_re = re.compile(
diff --git a/aircox/management/commands/sounds_quality_check.py b/aircox/management/commands/sounds_quality_check.py
index b25b8d4..b2469b0 100755
--- a/aircox/management/commands/sounds_quality_check.py
+++ b/aircox/management/commands/sounds_quality_check.py
@@ -9,7 +9,7 @@ from argparse import RawTextHelpFormatter
 
 from django.core.management.base import BaseCommand, CommandError
 
-logger = logging.getLogger('aircox.tools')
+logger = logging.getLogger('aircox.commands')
 
 
 class Stats:
diff --git a/aircox/management/commands/streamer.py b/aircox/management/commands/streamer.py
index c3c66a0..31b0485 100755
--- a/aircox/management/commands/streamer.py
+++ b/aircox/management/commands/streamer.py
@@ -6,27 +6,31 @@ used to:
 - cancels Diffusions that have an archive but could not have been played;
 - run Liquidsoap
 """
+# TODO:
+# x controllers: remaining
+# x diffusion conflicts
+# x cancel
+# x when liquidsoap fails to start/exists: exit
+# - handle restart after failure
+# - file in queue without sound not logged?
+# - is stream restart after live ok?
 from argparse import RawTextHelpFormatter
 import time
 
 import pytz
-import tzlocal
+from django.db.models import Q
 from django.core.management.base import BaseCommand
 from django.utils import timezone as tz
 
-from aircox.models import Station, Episode, Diffusion, Track, Sound, Log
 from aircox.controllers import Streamer, PlaylistSource
+from aircox.models import Station, Episode, Diffusion, Track, Sound, Log
+from aircox.utils import date_range
+
 
 # force using UTC
 tz.activate(pytz.UTC)
 
 
-# FIXME liquidsoap does not manage timezones -- we have to convert
-#       'on_air' metadata we get from it into utc one in order to work
-#       correctly.
-local_tz = tzlocal.get_localzone()
-
-
 class Monitor:
     """
     Log and launch diffusions for the given station.
@@ -42,6 +46,8 @@ class Monitor:
     """
     streamer = None
     """ Streamer controller """
+    delay = None
+    """ Timedelta: minimal delay between two call of monitor. """
     logs = None
     """ Queryset to station's logs (ordered by -pk) """
     cancel_timeout = 20
@@ -65,8 +71,11 @@ class Monitor:
         """ Log of last triggered item (sound or diffusion). """
         return self.logs.start().with_diff().first()
 
-    def __init__(self, streamer, **kwargs):
+    def __init__(self, streamer, delay, cancel_timeout, **kwargs):
         self.streamer = streamer
+        # adding time ensure all calculation have a margin
+        self.delay = delay + tz.timedelta(seconds=5)
+        self.cancel_timeout = cancel_timeout
         self.__dict__.update(kwargs)
         self.logs = self.get_logs_queryset()
 
@@ -81,6 +90,27 @@ class Monitor:
             return
 
         self.streamer.fetch()
+
+        # Skip tracing - analyzis:
+        # Reason: multiple database request every x seconds, reducing it.
+        # We could skip this part when remaining time is higher than a minimal
+        # value (which should be derived from Command's delay). Problems:
+        # - How to trace tracks? (+ Source can change: caching log might sucks)
+        # - if liquidsoap's source/request changes: remaining time goes higher,
+        #   thus avoiding fetch
+        #
+        # Approach: something like having a mean time, such as:
+        #
+        # ```
+        # source = stream.source
+        # mean_time = source.air_time
+        #           + min(next_track.timestamp, source.remaining)
+        #           - (command.delay + 1)
+        # trace_required = \/ source' != source
+        #                  \/ source.uri' != source.uri
+        #                  \/ now < mean_time
+        # ```
+        #
         source = self.streamer.source
         if source and source.uri:
             log = self.trace_sound(source)
@@ -102,21 +132,22 @@ class Monitor:
 
     def trace_sound(self, source):
         """ Return on air sound log (create if not present). """
-        sound_path, air_time = source.uri, source.air_time
+        air_uri, air_time = source.uri, source.air_time
 
         # check if there is yet a log for this sound on the source
-        delta = tz.timedelta(seconds=5)
-        air_times = (air_time - delta, air_time + delta)
-
-        log = self.logs.on_air().filter(source=source.id,
-                                        sound__path=sound_path,
-                                        date__range=air_times).first()
+        log = self.logs.on_air().filter(
+            Q(sound__path=air_uri) |
+            # sound can be null when arbitrary sound file is played
+            Q(sound__isnull=True, track__isnull=True, comment=air_uri),
+            source=source.id,
+            date__range=date_range(air_time, self.delay),
+        ).first()
         if log:
             return log
 
         # get sound
         diff = None
-        sound = Sound.objects.filter(path=sound_path).first()
+        sound = Sound.objects.filter(path=air_uri).first()
         if sound and sound.episode_id is not None:
             diff = Diffusion.objects.episode(id=sound.episode_id).on_air() \
                                     .now(air_time).first()
@@ -124,7 +155,7 @@ class Monitor:
         # log sound on air
         return self.log(type=Log.Type.on_air, date=source.air_time,
                         source=source.id, sound=sound, diffusion=diff,
-                        comment=sound_path)
+                        comment=air_uri)
 
     def trace_tracks(self, log):
         """
@@ -155,19 +186,56 @@ class Monitor:
         Handle scheduled diffusion, trigger if needed, preload playlists
         and so on.
         """
-        # TODO: restart
-        # TODO: handle conflict + cancel
-        diff = Diffusion.objects.station(self.station).on_air().now() \
+        # TODO: program restart
+
+        # Diffusion conflicts are handled by the way a diffusion is defined
+        # as candidate for the next dealer's start.
+        #
+        # ```
+        # logged_diff: /\ \A diff in diffs: \E log: /\ log.type = START
+        #                                           /\ log.diff = diff
+        #                                           /\ log.date = diff.start
+        # queue_empty: /\ dealer.queue is empty
+        #              /\ \/ ~dealer.on_air
+        #                 \/ dealer.remaining < delay
+        #
+        # start_allowed: /\ diff not in logged_diff
+        #                /\ queue_empty
+        #
+        # start_canceled: /\ diff not in logged diff
+        #                 /\ ~queue_empty
+        #                 /\ diff.start < now + cancel_timeout
+        # ```
+        #
+        now = tz.now()
+        diff = Diffusion.objects.station(self.station).on_air().now(now) \
                         .filter(episode__sound__type=Sound.Type.archive) \
                         .first()
-        log = self.logs.start().filter(diffusion=diff) if diff else None
+        # Can't use delay: diffusion may start later than its assigned start.
+        log = None if not diff else self.logs.start().filter(diffusion=diff)
         if not diff or log:
             return
 
-        playlist = Sound.objects.episode(id=diff.episode_id).paths()
         dealer = self.streamer.dealer
-        dealer.queue(*playlist)
-        self.log(type=Log.Type.start, source=dealer.id, diffusion=diff,
+        # start
+        if not dealer.queue and dealer.rid is None or \
+                dealer.remaining < self.delay.total_seconds():
+            self.start_diff(dealer, diff)
+
+        # cancel
+        if diff.start < now - self.cancel_timeout:
+            self.cancel_diff(dealer, diff)
+
+    def start_diff(self, source, diff):
+        playlist = Sound.objects.episode(id=diff.episode_id).paths()
+        source.append(*playlist)
+        self.log(type=Log.Type.start, source=source.id, diffusion=diff,
+                 comment=str(diff))
+
+    def cancel_diff(self, source, diff):
+        diff.type = Diffusion.Type.cancel
+        diff.save()
+        self.log(type=Log.Type.cancel, source=source.id, diffusion=diff,
                  comment=str(diff))
 
     def sync(self):
@@ -207,7 +275,8 @@ class Command (BaseCommand):
             '-d', '--delay', type=int,
             default=1000,
             help='time to sleep in MILLISECONDS between two updates when we '
-                 'monitor'
+                 'monitor. This influence the delay before a diffusion is '
+                 'launched.'
         )
         group.add_argument(
             '-s', '--station', type=str, action='append',
@@ -215,7 +284,7 @@ class Command (BaseCommand):
                  'all stations'
         )
         group.add_argument(
-            '-t', '--timeout', type=int,
+            '-t', '--timeout', type=float,
             default=Monitor.cancel_timeout,
             help='time to wait in MINUTES before canceling a diffusion that '
                  'should have ran but did not. '
@@ -226,7 +295,6 @@ class Command (BaseCommand):
                config=None, run=None, monitor=None,
                station=[], delay=1000, timeout=600,
                **options):
-
         stations = Station.objects.filter(name__in=station) if station else \
                    Station.objects.all()
         streamers = [Streamer(station) for station in stations]
@@ -238,14 +306,15 @@ class Command (BaseCommand):
                 streamer.run_process()
 
         if monitor:
-            monitors = [Monitor(streamer, cancel_timeout=timeout)
+            delay = tz.timedelta(milliseconds=delay)
+            timeout = tz.timedelta(minutes=timeout)
+            monitors = [Monitor(streamer, delay, timeout)
                         for streamer in streamers]
 
-            delay = delay / 1000
-            while True:
+            while not run or streamer.is_running:
                 for monitor in monitors:
                     monitor.monitor()
-                time.sleep(delay)
+                time.sleep(delay.total_seconds())
 
         if run:
             for streamer in streamers:
diff --git a/aircox/models/__pycache__/episode.cpython-37.pyc b/aircox/models/__pycache__/episode.cpython-37.pyc
index 5daa7d1..0246dd5 100644
Binary files a/aircox/models/__pycache__/episode.cpython-37.pyc and b/aircox/models/__pycache__/episode.cpython-37.pyc differ
diff --git a/aircox/models/__pycache__/log.cpython-37.pyc b/aircox/models/__pycache__/log.cpython-37.pyc
index 893589b..556d5da 100644
Binary files a/aircox/models/__pycache__/log.cpython-37.pyc and b/aircox/models/__pycache__/log.cpython-37.pyc differ
diff --git a/aircox/models/episode.py b/aircox/models/episode.py
index 5d31e4c..3c9a829 100644
--- a/aircox/models/episode.py
+++ b/aircox/models/episode.py
@@ -122,7 +122,7 @@ class Diffusion(BaseRerun):
     class Type(IntEnum):
         on_air = 0x00
         unconfirmed = 0x01
-        canceled = 0x02
+        cancel = 0x02
 
     episode = models.ForeignKey(
         Episode, models.CASCADE,
diff --git a/aircox/models/log.py b/aircox/models/log.py
index 770297e..6caf041 100644
--- a/aircox/models/log.py
+++ b/aircox/models/log.py
@@ -167,18 +167,14 @@ class Log(models.Model):
         """
         Source has been stopped, e.g. manually
         """
+        # Rule: \/ diffusion != null \/ sound != null
         start = 0x01
-        """
-        The diffusion or sound has been triggered by the streamer or
-        manually.
-        """
-        load = 0x02
-        """
-        A playlist has updated, and loading started. A related Diffusion
-        does not means that the playlist is only for it (e.g. after a
-        crash, it can reload previous remaining sound files + thoses of
-        the next diffusion)
-        """
+        """ Diffusion or sound has been request to be played. """
+        cancel = 0x02
+        """ Diffusion has been canceled. """
+        # Rule: \/ sound != null /\ track == null
+        #       \/ sound == null /\ track != null
+        #       \/ sound == null /\ track == null /\ comment = sound_path
         on_air = 0x03
         """
         The sound or diffusion has been detected occurring on air. Can
@@ -186,9 +182,7 @@ class Log(models.Model):
         them since they don't have an attached sound archive.
         """
         other = 0x04
-        """
-        Other log
-        """
+        """ Other log """
 
     station = models.ForeignKey(
         Station, models.CASCADE,
@@ -216,12 +210,6 @@ class Log(models.Model):
         max_length=512, blank=True, null=True,
         verbose_name=_('comment'),
     )
-
-    diffusion = models.ForeignKey(
-        Diffusion, models.SET_NULL,
-        blank=True, null=True, db_index=True,
-        verbose_name=_('Diffusion'),
-    )
     sound = models.ForeignKey(
         Sound, models.SET_NULL,
         blank=True, null=True, db_index=True,
@@ -232,6 +220,11 @@ class Log(models.Model):
         blank=True, null=True, db_index=True,
         verbose_name=_('Track'),
     )
+    diffusion = models.ForeignKey(
+        Diffusion, models.SET_NULL,
+        blank=True, null=True, db_index=True,
+        verbose_name=_('Diffusion'),
+    )
 
     objects = LogQuerySet.as_manager()
 
diff --git a/aircox/templates/aircox/scripts/station.liq b/aircox/templates/aircox/scripts/station.liq
index 818f673..4c74d5d 100755
--- a/aircox/templates/aircox/scripts/station.liq
+++ b/aircox/templates/aircox/scripts/station.liq
@@ -42,6 +42,11 @@ def interactive (id, s) =
                     description="Seek to a relative position",
                     usage="seek <duration>",
                     "seek", fun (x) ->  begin seek(s, x) end)
+    server.register(namespace=id,
+                    description="Get source's track remaining time",
+                    usage="remaining",
+                    "remaining", fun (_) ->  begin json_of(source.remaining(s)) end)
+
     s = store_metadata(id=id, size=1, s)
     add_skip_command(s)
     s
diff --git a/aircox/utils.py b/aircox/utils.py
index bc40228..34d2c4c 100755
--- a/aircox/utils.py
+++ b/aircox/utils.py
@@ -2,16 +2,18 @@ import datetime
 import django.utils.timezone as tz
 
 
-def date_range(date):
+def date_range(date, delta=None, **delta_kwargs):
     """
+    Return a range of provided date such as `[date-delta, date+delta]`.
+    :param date: the reference date
+    :param delta: timedelta
+    :param \**delta_kwargs: timedelta init arguments
+
     Return a datetime range for a given day, as:
     ```(date, 0:0:0:0; date, 23:59:59:999)```.
     """
-    date = date_or_default(date, tz.datetime)
-    return (
-        date.replace(hour=0, minute=0, second=0),
-        date.replace(hour=23, minute=59, second=59, microsecond=999)
-    )
+    delta = tz.timedelta(**delta_kwargs) if delta is None else delta
+    return [date - delta, date + delta]
 
 
 def cast_date(date, into=datetime.date):
diff --git a/setup.py b/setup.py
index be65c0d..44b04aa 100755
--- a/setup.py
+++ b/setup.py
@@ -15,12 +15,12 @@ def to_array (path):
 
 setup(
     name='aircox',
-    version='0.1',
+    version='0.9',
     license='GPLv3',
     author='bkfox',
-    description='Aircox is a radio programs manager that includes tools and cms',
+    description='Aircox is a radio programs manager including tools and cms',
     long_description=to_rst('README.md'),
-    url='http://bkfox.net/',
+    url='https://github.com/bkfox/aircox',
     packages=find_packages(),
     include_package_data=True,
     install_requires=to_array('requirements.txt'),