playback: fix crash with state restore [#89]

Fix an esoteric crash with queue synchronization during the playback
restore process.

Auxio will attempt to re-synchronize the queue index whenever it is
desynchronized, however during the check for if it's desynchronized,
Auxio would do a direct index of the queue, which could result in a
crash in situations where the desynchronized index is outside of the
queue bounds.

Fix this by replacing that unprotected access with a protected access,
which not only fixes the crash but also still correctly detects
desynchronization in that case.

Resolves #89.

CHANGELOG.md

@@ -1,7 +1,6 @@
 # Changelog
 
 ## dev [v2.2.2 or 2.3.0]
-
 #### What's New
 - New spanish translations and metadata [courtesy of n-berenice]
 
@@ -16,6 +15,7 @@ from the system theme was used [#80]
 - Fixed incorrect track numbers when the tag was formatted as NN/TT [#88]
 - Fixed years deliberately set as "0" showing up as "No Date"
 - Fixed headset management unexpectedly starting audio when the app initially opens
+- Fixed crash that would occur during a playback restore with specific queue states [#89]
 
 #### What's Changed
 - All cover art is now cropped to a 1:1 aspect ratio

app/src/main/java/org/oxycblt/auxio/playback/state/PlaybackStateManager.kt

@@ -40,6 +40,8 @@ import org.oxycblt.auxio.util.logE
  *
  * All access should be done with [PlaybackStateManager.getInstance].
  * @author OxygenCobalt
+ *
+ * TODO: Rework this to possibly handle gapless playback and more refined queue management.
  */
 class PlaybackStateManager private constructor() {
     // Playback
@@ -594,7 +596,9 @@ class PlaybackStateManager private constructor() {
      * Do a sanity check to make sure that the index lines up with the current song.
      */
     private fun doIndexSanityCheck() {
-        if (mSong != null && mSong != mQueue[mIndex]) {
+        // Note: Be careful with how we handle the queue since a possible index desync
+        // could easily result in an OOB issue.
+        if (mSong != null && mSong != mQueue.getOrNull(mIndex)) {
             val correctedIndex = mQueue.wobblyIndexOfFirst(mIndex, mSong)
 
             if (correctedIndex > -1) {

info/ADDITIONS.md

@@ -9,7 +9,6 @@ While I do like adding new behavior/UI customizations, these will be looked at m
 
 ## Feature Additions and UI Changes
 These arent as likely to be accepted. As I said, I do not want Auxio to become overly bloated with features that are rarely used, therefore I only tend to accept features that:
-
 - Benefit **my own** usage
 - Are in line with Auxio's purpose as a music player
 
@@ -25,3 +24,4 @@ Feel free to fork Auxio to add your own feature set however.
 - Gapless Playback [#35] (Technical issues, may change in the future)
 - Reduce leading instrument [#45] (Technical issues, Out of scope)
 - Opening music through a provider [#30] (Out of scope)
+- Cuesheet support [#83]