From ed87ab8dd10f74ebd99b004651c0a8213527eb41 Mon Sep 17 00:00:00 2001
From: Arjun Naik <arjun@arjunnaik.in>
Date: Mon, 28 Jul 2014 22:48:26 +0200
Subject: [PATCH] Added a playback history object to the core.

---
 mopidy/core/__init__.py    |  1 +
 mopidy/core/actor.py       |  7 +++++++
 mopidy/core/history.py     | 42 ++++++++++++++++++++++++++++++++++++++
 mopidy/core/playback.py    |  1 +
 tests/core/test_history.py | 27 ++++++++++++++++++++++++
 5 files changed, 78 insertions(+)
 create mode 100644 mopidy/core/history.py
 create mode 100644 tests/core/test_history.py

diff --git a/mopidy/core/__init__.py b/mopidy/core/__init__.py
index f49bbbe7..d857d4fb 100644
--- a/mopidy/core/__init__.py
+++ b/mopidy/core/__init__.py
@@ -2,6 +2,7 @@ from __future__ import unicode_literals
 
 # flake8: noqa
 from .actor import Core
+from .history import TrackHistory
 from .library import LibraryController
 from .listener import CoreListener
 from .playback import PlaybackController, PlaybackState
diff --git a/mopidy/core/actor.py b/mopidy/core/actor.py
index 66f2aa82..bb5058ee 100644
--- a/mopidy/core/actor.py
+++ b/mopidy/core/actor.py
@@ -7,6 +7,7 @@ import pykka
 
 from mopidy import audio, backend, mixer
 from mopidy.audio import PlaybackState
+from mopidy.core.history import TrackHistory
 from mopidy.core.library import LibraryController
 from mopidy.core.listener import CoreListener
 from mopidy.core.playback import PlaybackController
@@ -23,6 +24,10 @@ class Core(
     """The library controller. An instance of
     :class:`mopidy.core.LibraryController`."""
 
+    history = None
+    """The playback history. An instance of
+    :class:`mopidy.core.TrackHistory`"""
+
     playback = None
     """The playback controller. An instance of
     :class:`mopidy.core.PlaybackController`."""
@@ -42,6 +47,8 @@ class Core(
 
         self.library = LibraryController(backends=self.backends, core=self)
 
+        self.history = TrackHistory()
+
         self.playback = PlaybackController(
             mixer=mixer, backends=self.backends, core=self)
 
diff --git a/mopidy/core/history.py b/mopidy/core/history.py
new file mode 100644
index 00000000..7f617441
--- /dev/null
+++ b/mopidy/core/history.py
@@ -0,0 +1,42 @@
+from __future__ import unicode_literals
+
+import logging
+
+from mopidy.models import Track
+
+
+logger = logging.getLogger(__name__)
+
+
+class TrackHistory():
+    track_list = []
+
+    def add_track(self, track):
+        """
+        :param track: track to change to
+        :type track: :class:`mopidy.models.Track`
+        """
+        if type(track) is not Track:
+            logger.warning('Cannot add non-Track type object to TrackHistory')
+            return
+
+        # Reorder the track history if the track is already present.
+        if track in self.track_list:
+            self.track_list.remove(track)
+        self.track_list.insert(0, track)
+
+    def get_history_size(self):
+        """
+        Returns the number of tracks in the history.
+        :returns: The number of tracks in the history.
+        :rtype :int
+        """
+        return len(self.track_list)
+
+    def get_history(self):
+        """
+        Returns the history.
+        :returns: The history as a list of `mopidy.models.Track`
+        :rtype: L{`mopidy.models.Track`}
+        """
+        return self.track_list
diff --git a/mopidy/core/playback.py b/mopidy/core/playback.py
index df48422d..f0262830 100644
--- a/mopidy/core/playback.py
+++ b/mopidy/core/playback.py
@@ -248,6 +248,7 @@ class PlaybackController(object):
         if success:
             self.core.tracklist.mark_playing(tl_track)
             # TODO: replace with stream-changed
+            self.core.history.add_track(tl_track.track)
             self._trigger_track_playback_started()
         else:
             self.core.tracklist.mark_unplayable(tl_track)
diff --git a/tests/core/test_history.py b/tests/core/test_history.py
new file mode 100644
index 00000000..4e9b059c
--- /dev/null
+++ b/tests/core/test_history.py
@@ -0,0 +1,27 @@
+import unittest
+
+from mopidy.core import TrackHistory
+
+from mopidy.models import Track
+
+
+class PlaybackHistoryTest(unittest.TestCase):
+    def setUp(self):
+        self.tracks = [
+            Track(uri='dummy1:a', name='foo'),
+            Track(uri='dummy2:a', name='foo'),
+            Track(uri='dummy3:a', name='bar')
+        ]
+        self.history = TrackHistory()
+
+    def test_add_track(self):
+        self.history.add_track(self.tracks[0])
+        self.assertEqual(self.history.get_history_size(), 1)
+
+    def test_track_order(self):
+        self.history.add_track(self.tracks[0])
+        self.history.add_track(self.tracks[1])
+        self.history.add_track(self.tracks[2])
+        self.history.add_track(self.tracks[0])
+        self.assertEqual(self.history.get_history_size(), 3)
+        self.assertEqual(self.history.get_history()[0], self.tracks[0])
\ No newline at end of file