Added a spotlight feature that shows the user how to switch between

remote and streaming mode. Also updated GaplessHeaderService to require
less bandwidth, with more error checking.

src/musikdroid/app/build.gradle

@@ -92,6 +92,7 @@ dependencies {
     implementation 'com.google.android.exoplayer:extension-okhttp:r2.5.4'
     implementation 'com.simplecityapps:recyclerview-fastscroll:1.0.16'
     implementation 'com.facebook.stetho:stetho:1.5.0'
+    implementation 'com.github.wooplr:Spotlight:1.2.3'
 
     implementation 'com.android.support:appcompat-v7:26.1.0'
     implementation 'com.android.support:recyclerview-v7:26.1.0'

src/musikdroid/app/src/main/java/io/casey/musikcube/remote/service/gapless/GaplessHeaderService.kt

@@ -22,7 +22,7 @@ import javax.inject.Inject
 /**
  * When MP3 files are transcoded on-demand, the required metadata for gapless playback isn't
  * available yet. So, once we know the transocded files have been downloaded, we run this
- * service to fetch and replace the first 32000 bytes of the file, which should ensure the
+ * service to fetch and replace the first few bytes of the file, which should ensure the
  * required header is present, and subsequent plays are gapless.
  */
 class GaplessHeaderService {
@@ -78,11 +78,11 @@ class GaplessHeaderService {
         var newState = -1
 
         if (fn.exists()) {
-            /* the first 32000 bytes should be more than enough to snag the
+            /* the first few bytes should be more than enough to snag the
             LAME header that contains gapless playback metadata. just rewrite
             those bytes in the already-downloaded file */
             val req = Request.Builder()
-                .addHeader("Range", "bytes=0-32000")
+                .addHeader("Range", "bytes=0-$HEADER_SIZE_BYTES")
                 .url(url)
                 .build()
 
@@ -100,7 +100,7 @@ class GaplessHeaderService {
                 if (bytes?.isNotEmpty() == true) {
                     RandomAccessFile(fn, "rw").use {
                         it.seek(0)
-                        it.write(bytes)
+                        it.write(bytes, 0, Math.min(bytes.size, HEADER_SIZE_BYTES))
                     }
                     newState = GaplessTrack.UPDATED
                 }
@@ -120,5 +120,6 @@ class GaplessHeaderService {
 
     companion object {
         val MESSAGE_PROCESS = 1
+        val HEADER_SIZE_BYTES = 6400
     }
 }

src/musikdroid/app/src/main/java/io/casey/musikcube/remote/service/playback/PlayerWrapper.kt

@@ -106,7 +106,6 @@ abstract class PlayerWrapper {
     }
 
     companion object {
-        private val TYPE = Type.ExoPlayer
         private val DUCK_COEF = 0.2f /* volume = 20% when ducked */
         private val DUCK_NONE = -1.0f
 

src/musikdroid/app/src/main/java/io/casey/musikcube/remote/ui/home/activity/MainActivity.kt

@@ -4,19 +4,18 @@ import android.app.Dialog
 import android.content.Context
 import android.content.Intent
 import android.content.SharedPreferences
+import android.graphics.Color
 import android.net.Uri
 import android.os.Bundle
 import android.os.Handler
 import android.support.v4.app.DialogFragment
 import android.support.v7.app.AlertDialog
-import android.view.LayoutInflater
-import android.view.Menu
-import android.view.MenuItem
-import android.view.View
+import android.view.*
 import android.widget.CheckBox
 import android.widget.CompoundButton
 import android.widget.SeekBar
 import android.widget.TextView
+import com.wooplr.spotlight.SpotlightView
 import io.casey.musikcube.remote.R
 import io.casey.musikcube.remote.service.playback.PlaybackState
 import io.casey.musikcube.remote.service.playback.RepeatMode
@@ -101,6 +100,7 @@ class MainActivity : BaseActivity() {
         scheduleUpdateTime(true)
         runUpdateCheck()
         initObservers()
+        registerLayoutListener()
     }
 
     override fun onCreateOptionsMenu(menu: Menu): Boolean {
@@ -157,9 +157,15 @@ class MainActivity : BaseActivity() {
         disposables.add(data.provider.observeState().subscribe(
             { states ->
                 when (states.first) {
-                    IDataProvider.State.Connected -> rebindUi()
-                    IDataProvider.State.Disconnected -> clearUi()
-                    else -> { }
+                    IDataProvider.State.Connected -> {
+                        rebindUi()
+                        checkShowSpotlight()
+                    }
+                    IDataProvider.State.Disconnected -> {
+                        clearUi()
+                    }
+                    else -> {
+                    }
                 }
             }, { /* error */ }))
 
@@ -351,6 +357,45 @@ class MainActivity : BaseActivity() {
         }
     }
 
+    private fun registerLayoutListener() {
+        window.decorView.viewTreeObserver.addOnGlobalLayoutListener(
+            object : ViewTreeObserver.OnGlobalLayoutListener {
+                override fun onGlobalLayout() {
+                    val toolbarButton = findViewById<View>(R.id.action_remote_toggle)
+                    if (toolbarButton != null && data.provider.state == IDataProvider.State.Connected) {
+                        checkShowSpotlight()
+                        window.decorView.viewTreeObserver.removeOnGlobalLayoutListener(this)
+                    }
+                }
+            })
+    }
+
+    private fun checkShowSpotlight() {
+        val toolbarButton = findViewById<View>(R.id.action_remote_toggle)
+        if (toolbarButton != null) {
+            SpotlightView.Builder(this@MainActivity)
+                .introAnimationDuration(400)
+                .enableRevealAnimation(true)
+                .performClick(true)
+                .fadeinTextDuration(400)
+                .headingTvColor(getColorCompat(R.color.color_accent))
+                .headingTvSize(24)
+                .headingTvText(getString(R.string.spotlight_playback_mode_title))
+                .subHeadingTvColor(Color.parseColor("#ffffff"))
+                .subHeadingTvSize(16)
+                .subHeadingTvText(getString(R.string.spotlight_playback_mode_message))
+                .maskColor(Color.parseColor("#dc000000"))
+                .target(toolbarButton)
+                .lineAnimDuration(400)
+                .lineAndArcColor(getColorCompat(R.color.color_primary))
+                .dismissOnTouch(true)
+                .dismissOnBackPress(true)
+                .enableDismissAfterShown(true)
+                .usageId(SPOTLIGHT_STREAMING_ID)
+                .show()
+        }
+    }
+
     private fun clearUi() {
         metadataView.clear()
         rebindUi()
@@ -523,6 +568,8 @@ class MainActivity : BaseActivity() {
     }
 
     companion object {
+        private val SPOTLIGHT_STREAMING_ID = "spotlight_streaming_mode"
+
         private var REPEAT_TO_STRING_ID: MutableMap<RepeatMode, Int> = mutableMapOf(
             RepeatMode.None to R.string.button_repeat_off,
             RepeatMode.List to R.string.button_repeat_list,

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

@@ -139,4 +139,6 @@
     <string name="playlist_not_created">could not create playlist \'%s\'</string>
     <string name="playlist_deleted">playlist \'%s\' deleted</string>
     <string name="playlist_not_deleted">could not delete playlist \'%s\'</string>
+    <string name="spotlight_playback_mode_title">playback mode</string>
+    <string name="spotlight_playback_mode_message">want to listen to music from your phone?\nclick here to switch between remote control and streaming modes.</string>
 </resources>