From 238b21c2e259eac0d033013a732edfef4dbd0a8e Mon Sep 17 00:00:00 2001
From: Jays2Kings <jays@outlook.com>
Date: Sat, 20 Aug 2022 22:50:17 -0400
Subject: [PATCH] Scroll through library entries (instead of just categories)
 by fastscrolling then moving to the middle of the screen

maybe by the release notes i'll have a better way of explaining that

closes #1348 in a way I can live with
---
 .../tachiyomi/ui/library/LibraryFastScroll.kt | 36 ++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryFastScroll.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryFastScroll.kt
index 47a3bdba3a..25f37d0460 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryFastScroll.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryFastScroll.kt
@@ -2,15 +2,37 @@ package eu.kanade.tachiyomi.ui.library
 
 import android.content.Context
 import android.util.AttributeSet
+import android.view.HapticFeedbackConstants
+import android.view.MotionEvent
 import eu.kanade.tachiyomi.ui.base.MaterialFastScroll
+import eu.kanade.tachiyomi.util.system.dpToPxEnd
+import eu.kanade.tachiyomi.util.system.isLTR
+import kotlin.math.abs
+import kotlin.math.min
 
 class LibraryFastScroll @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null) :
     MaterialFastScroll(context, attrs) {
 
+    private var currentX = 0f
+
+    override fun onTouchEvent(event: MotionEvent): Boolean {
+        val oldFastScroll = categoryFastScroll
+        currentX = event.x
+        if (categoryFastScroll != oldFastScroll && canScroll) {
+            performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP)
+        }
+        return super.onTouchEvent(event)
+    }
+
+    private val categoryFastScroll: Boolean
+        get() = abs(currentX - handle.x) >= min(200, width / 2)
+
     override fun setRecyclerViewPosition(y: Float) {
         if (recyclerView != null) {
             val adapter = recyclerView.adapter as? LibraryCategoryAdapter ?: return super.setRecyclerViewPosition(y)
-            if (adapter.isSingleCategory) return super.setRecyclerViewPosition(y)
+            if (adapter.isSingleCategory || categoryFastScroll) {
+                return super.setRecyclerViewPosition(y)
+            }
             var targetPos = getTargetPos(y)
             val category = when (val item = adapter.getItem(targetPos)) {
                 is LibraryItem -> {
@@ -24,4 +46,16 @@ class LibraryFastScroll @JvmOverloads constructor(context: Context, attrs: Attri
             updateBubbleText(targetPos)
         }
     }
+
+    override fun setBubbleAndHandlePosition(y: Float) {
+        super.setBubbleAndHandlePosition(y)
+        if (bubbleEnabled) {
+            bubble.translationX =
+                if (categoryFastScroll) {
+                250f * (if (resources.isLTR) -1 else 1)
+            } else {
+                currentX - handle.x
+            } + (-45f).dpToPxEnd(resources)
+        }
+    }
 }