fixing some video playback glitches

app/src/main/kotlin/com/simplemobiletools/gallery/pro/fragments/VideoFragment.kt

@@ -49,8 +49,11 @@ class VideoFragment : ViewPagerFragment(), TextureView.SurfaceTextureListener, S
     private var mIsPlaying = false
     private var mIsDragged = false
     private var mWasVideoStarted = false
+    private var mWasPlayerInited = false
+    private var mWasLastPositionRestored = false
     private var mCurrTime = 0
     private var mDuration = 0
+    private var mPositionWhenInit = 0
 
     private var mExoPlayer: SimpleExoPlayer? = null
     private var mVideoSize = Point(0, 0)
@@ -496,6 +499,9 @@ class VideoFragment : ViewPagerFragment(), TextureView.SurfaceTextureListener, S
 
     override fun onProgressChanged(seekBar: SeekBar, progress: Int, fromUser: Boolean) {
         if (mExoPlayer != null && fromUser) {
+            if (!mWasPlayerInited) {
+                mPositionWhenInit = progress
+            }
             setPosition(progress)
         }
     }
@@ -553,7 +559,8 @@ class VideoFragment : ViewPagerFragment(), TextureView.SurfaceTextureListener, S
             setPosition(0)
         }
 
-        if (mStoredRememberLastVideoPosition) {
+        if (mStoredRememberLastVideoPosition && !mWasLastPositionRestored) {
+            mWasLastPositionRestored = true
             restoreLastVideoSavedPosition()
         }
 
@@ -614,6 +621,12 @@ class VideoFragment : ViewPagerFragment(), TextureView.SurfaceTextureListener, S
                 playVideo()
             }
         }
+
+        if (mPositionWhenInit != 0 && !mWasPlayerInited) {
+            setPosition(mPositionWhenInit)
+            mPositionWhenInit = 0
+        }
+        mWasPlayerInited = true
     }
 
     private fun videoCompleted() {