fix: #1574 previous button incorrect behaviour

app/src/main/java/code/name/monkey/retromusic/Constants.kt

@@ -161,4 +161,6 @@ const val CIRCLE_PLAY_BUTTON = "circle_play_button"
 const val SWIPE_ANYWHERE_NOW_PLAYING = "swipe_anywhere_now_playing"
 const val PAUSE_HISTORY = "pause_history"
 const val MANAGE_AUDIO_FOCUS = "manage_audio_focus"
-const val SWIPE_DOWN_DISMISS = "swipe_to_dismiss"
+const val SWIPE_DOWN_DISMISS = "swipe_to_dismiss"
+const val PREF_PREV_SONG_ON_BACK_HEADSET = "prev_song_on_back_h"
+const val PREF_PREV_SONG_ON_BACK_BLUETOOTH = "prev_song_on_back_b"

app/src/main/java/code/name/monkey/retromusic/fragments/settings/OtherSettingsFragment.kt

@@ -14,15 +14,21 @@
  */
 package code.name.monkey.retromusic.fragments.settings
 
+import android.Manifest
+import android.content.pm.PackageManager
 import android.os.Bundle
 import android.view.View
 import androidx.appcompat.app.AppCompatDelegate
+import androidx.core.app.ActivityCompat
 import androidx.core.os.LocaleListCompat
 import androidx.preference.Preference
 import code.name.monkey.appthemehelper.common.prefs.supportv7.ATEListPreference
+import code.name.monkey.appthemehelper.util.VersionUtils
 import code.name.monkey.retromusic.LANGUAGE_NAME
 import code.name.monkey.retromusic.LAST_ADDED_CUTOFF
+import code.name.monkey.retromusic.PREF_PREV_SONG_ON_BACK_BLUETOOTH
 import code.name.monkey.retromusic.R
+import code.name.monkey.retromusic.activities.base.AbsBaseActivity
 import code.name.monkey.retromusic.extensions.installLanguageAndRecreate
 import code.name.monkey.retromusic.fragments.LibraryViewModel
 import code.name.monkey.retromusic.fragments.ReloadType.HomeSections
@@ -37,6 +43,26 @@ class OtherSettingsFragment : AbsSettingsFragment() {
     private val libraryViewModel by activityViewModel<LibraryViewModel>()
 
     override fun invalidateSettings() {
+        val bluetoothPreference: Preference? = findPreference(PREF_PREV_SONG_ON_BACK_BLUETOOTH)
+        if (VersionUtils.hasS()) {
+            bluetoothPreference?.setOnPreferenceChangeListener { _, newValue ->
+                if (newValue as Boolean) {
+                    if (ActivityCompat.checkSelfPermission(
+                            requireContext(),
+                            Manifest.permission.BLUETOOTH_CONNECT
+                        ) != PackageManager.PERMISSION_GRANTED
+                    ) {
+                        ActivityCompat.requestPermissions(
+                            requireActivity(), arrayOf(
+                                Manifest.permission.BLUETOOTH_CONNECT
+                            ), AbsBaseActivity.BLUETOOTH_PERMISSION_REQUEST
+                        )
+                    }
+                }
+                return@setOnPreferenceChangeListener true
+            }
+        }
+
         val languagePreference: ATEListPreference? = findPreference(LANGUAGE_NAME)
         languagePreference?.setOnPreferenceChangeListener { _, _ ->
             restartActivity()

app/src/main/java/code/name/monkey/retromusic/service/MediaSessionCallback.kt

@@ -25,11 +25,17 @@ import code.name.monkey.retromusic.model.Album
 import code.name.monkey.retromusic.model.Artist
 import code.name.monkey.retromusic.model.Playlist
 import code.name.monkey.retromusic.model.Song
-import code.name.monkey.retromusic.repository.*
+import code.name.monkey.retromusic.repository.AlbumRepository
+import code.name.monkey.retromusic.repository.ArtistRepository
+import code.name.monkey.retromusic.repository.GenreRepository
+import code.name.monkey.retromusic.repository.PlaylistRepository
+import code.name.monkey.retromusic.repository.SongRepository
+import code.name.monkey.retromusic.repository.TopPlayedRepository
 import code.name.monkey.retromusic.service.MusicService.Companion.CYCLE_REPEAT
 import code.name.monkey.retromusic.service.MusicService.Companion.TOGGLE_FAVORITE
 import code.name.monkey.retromusic.service.MusicService.Companion.TOGGLE_SHUFFLE
 import code.name.monkey.retromusic.util.MusicUtil
+import code.name.monkey.retromusic.util.PreferenceUtil
 import code.name.monkey.retromusic.util.logD
 import code.name.monkey.retromusic.util.logE
 import org.koin.core.component.KoinComponent
@@ -170,7 +176,12 @@ class MediaSessionCallback(
 
     override fun onSkipToPrevious() {
         super.onSkipToPrevious()
-        musicService.playPreviousSong(true)
+        if ((PreferenceUtil.shouldPreviousSongOnBackHeadset && musicService.isHeadsetConnected) ||
+            (PreferenceUtil.shouldPreviousSongOnBackBluetooth && musicService.isBluetoothConnected)) {
+            musicService.playPreviousSong(true)
+        } else {
+            musicService.back(true)
+        }
     }
 
     override fun onStop() {

app/src/main/java/code/name/monkey/retromusic/service/MusicService.kt

@@ -13,22 +13,39 @@
  */
 package code.name.monkey.retromusic.service
 
+import android.Manifest
 import android.annotation.SuppressLint
 import android.app.NotificationManager
 import android.app.PendingIntent
 import android.appwidget.AppWidgetManager
 import android.bluetooth.BluetoothDevice
-import android.content.*
+import android.bluetooth.BluetoothManager
+import android.bluetooth.BluetoothProfile
+import android.content.BroadcastReceiver
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import android.content.SharedPreferences
 import android.content.SharedPreferences.OnSharedPreferenceChangeListener
+import android.content.pm.PackageManager
 import android.content.pm.ServiceInfo
 import android.database.ContentObserver
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.graphics.drawable.Drawable
+import android.media.AudioDeviceInfo
 import android.media.AudioManager
-import android.os.*
+import android.os.Binder
+import android.os.Build
 import android.os.Build.VERSION
 import android.os.Build.VERSION_CODES
+import android.os.Bundle
+import android.os.Handler
+import android.os.HandlerThread
+import android.os.IBinder
+import android.os.Looper
+import android.os.PowerManager
 import android.os.PowerManager.WakeLock
 import android.provider.MediaStore
 import android.support.v4.media.MediaBrowserCompat
@@ -37,6 +54,7 @@ import android.support.v4.media.session.MediaSessionCompat
 import android.support.v4.media.session.PlaybackStateCompat
 import android.util.Log
 import android.widget.Toast
+import androidx.core.app.ActivityCompat
 import androidx.core.app.ServiceCompat
 import androidx.core.content.ContextCompat
 import androidx.core.content.edit
@@ -45,9 +63,24 @@ import androidx.core.os.BundleCompat
 import androidx.media.MediaBrowserServiceCompat
 import androidx.preference.PreferenceManager
 import code.name.monkey.appthemehelper.util.VersionUtils
-import code.name.monkey.retromusic.*
+import code.name.monkey.retromusic.ALBUM_ART_ON_LOCK_SCREEN
+import code.name.monkey.retromusic.BLURRED_ALBUM_ART
+import code.name.monkey.retromusic.BuildConfig
+import code.name.monkey.retromusic.CLASSIC_NOTIFICATION
+import code.name.monkey.retromusic.COLORED_NOTIFICATION
+import code.name.monkey.retromusic.CROSS_FADE_DURATION
+import code.name.monkey.retromusic.PLAYBACK_PITCH
+import code.name.monkey.retromusic.PLAYBACK_SPEED
+import code.name.monkey.retromusic.R
+import code.name.monkey.retromusic.TOGGLE_HEADSET
 import code.name.monkey.retromusic.activities.LockScreenActivity
-import code.name.monkey.retromusic.appwidgets.*
+import code.name.monkey.retromusic.appwidgets.AppWidgetBig
+import code.name.monkey.retromusic.appwidgets.AppWidgetCard
+import code.name.monkey.retromusic.appwidgets.AppWidgetCircle
+import code.name.monkey.retromusic.appwidgets.AppWidgetClassic
+import code.name.monkey.retromusic.appwidgets.AppWidgetMD3
+import code.name.monkey.retromusic.appwidgets.AppWidgetSmall
+import code.name.monkey.retromusic.appwidgets.AppWidgetText
 import code.name.monkey.retromusic.auto.AutoMediaIDHelper
 import code.name.monkey.retromusic.auto.AutoMusicProvider
 import code.name.monkey.retromusic.extensions.showToast
@@ -89,12 +122,18 @@ import com.bumptech.glide.Glide
 import com.bumptech.glide.request.target.CustomTarget
 import com.bumptech.glide.request.target.Target
 import com.bumptech.glide.request.transition.Transition
-import kotlinx.coroutines.*
+import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers.Default
 import kotlinx.coroutines.Dispatchers.IO
 import kotlinx.coroutines.Dispatchers.Main
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.Runnable
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import org.koin.java.KoinJavaComponent.get
-import java.util.*
+import java.util.Objects
+import java.util.Random
 
 
 /**
@@ -232,7 +271,31 @@ class MusicService : MediaBrowserServiceCompat(),
     @JvmField
     var shuffleMode = 0
     private val songPlayCountHelper = SongPlayCountHelper()
-
+    val isHeadsetConnected: Boolean
+        get(){
+            val audioManager = ContextCompat.getSystemService(this, AudioManager::class.java)
+                ?: return false
+            return VersionUtils.hasMarshmallow() &&
+                audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS).any { device ->
+                    device.type == AudioDeviceInfo.TYPE_WIRED_HEADPHONES
+                            || device.type == AudioDeviceInfo.TYPE_WIRED_HEADSET
+                }
+        }
+    val isBluetoothConnected: Boolean
+        get() {
+            val bluetoothAdapter = ContextCompat.getSystemService(
+                this,
+                BluetoothManager::class.java
+            )?.adapter ?: return false
+            if(VersionUtils.hasS() &&
+                ActivityCompat.checkSelfPermission(
+                    this,
+                    Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED){
+                return false
+            }
+            val headsetState = bluetoothAdapter.getProfileConnectionState(BluetoothProfile.HEADSET)
+            return (headsetState == BluetoothProfile.STATE_CONNECTED)
+        }
     private val bluetoothReceiver: BroadcastReceiver = object : BroadcastReceiver() {
         override fun onReceive(context: Context, intent: Intent) {
             val action = intent.action

app/src/main/java/code/name/monkey/retromusic/util/PreferenceUtil.kt

@@ -340,6 +340,18 @@ object PreferenceUtil {
             MANAGE_AUDIO_FOCUS, false
         )
 
+
+    val shouldPreviousSongOnBackHeadset
+        get() = sharedPreferences.getBoolean(
+            PREF_PREV_SONG_ON_BACK_HEADSET, false
+        )
+
+    val shouldPreviousSongOnBackBluetooth
+        get() = sharedPreferences.getBoolean(
+            PREF_PREV_SONG_ON_BACK_BLUETOOTH, false
+        )
+
+
     val isLockScreen get() = sharedPreferences.getBoolean(LOCK_SCREEN, false)
 
     @Suppress("deprecation")

app/src/main/res/values/strings.xml

@@ -563,4 +563,9 @@
     <string name="you_will_be_forwarded_to_the_issue_tracker_website">You will be forwarded to the issue tracker website.</string>
     <string name="your_account_data_is_only_used_for_authentication">Your account data is only used for authentication.</string>
     <string name="could_not_write_tags_to_file">Could not write tags to the music file!</string>
+    <string name="pref_header_media_back_behavior">Previous Media Button Behavior</string>
+    <string name="pref_title_prev_song_on_back_headset">Previous song on headset</string>
+    <string name="pref_title_prev_song_on_back_bluetooth">Previous song on bluetooth</string>
+    <string name="pref_summary_prev_song_on_back_headset">Media button will play the previous song instead of seeking to start of media, when connected to a headset</string>
+    <string name="pref_summary_prev_song_on_back_bluetooth">Media button will play the previous song instead of seeking to start of media, when connected to a blueooth device</string>
 </resources>

app/src/main/res/xml/pref_advanced.xml

@@ -64,6 +64,27 @@
 
 
     </code.name.monkey.appthemehelper.common.prefs.supportv7.ATEPreferenceCategory>
+
+    <code.name.monkey.appthemehelper.common.prefs.supportv7.ATEPreferenceCategory
+        android:layout="@layout/preference_category_title"
+        android:title="@string/pref_header_media_back_behavior">
+
+        <code.name.monkey.appthemehelper.common.prefs.supportv7.ATESwitchPreference
+            android:defaultValue="false"
+            android:key="prev_song_on_back_h"
+            android:layout="@layout/list_item_view_switch"
+            android:summary="@string/pref_summary_prev_song_on_back_headset"
+            android:title="@string/pref_title_prev_song_on_back_headset" />
+
+        <code.name.monkey.appthemehelper.common.prefs.supportv7.ATESwitchPreference
+            android:defaultValue="false"
+            android:key="prev_song_on_back_b"
+            android:layout="@layout/list_item_view_switch"
+            android:summary="@string/pref_summary_prev_song_on_back_bluetooth"
+            android:title="@string/pref_title_prev_song_on_back_bluetooth" />
+
+    </code.name.monkey.appthemehelper.common.prefs.supportv7.ATEPreferenceCategory>
+
     <code.name.monkey.appthemehelper.common.prefs.supportv7.ATEListPreference
         android:defaultValue="auto"
         android:entries="@array/pref_language_names"