Less janky enum iteration

app/src/main/java/eu/kanade/tachiyomi/ui/reader/setting/OrientationType.kt

@@ -6,7 +6,7 @@ import android.content.res.Resources
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
 import eu.kanade.tachiyomi.R
-import kotlin.math.max
+import eu.kanade.tachiyomi.util.lang.next
 
 enum class OrientationType(val prefValue: Int, val flag: Int, @StringRes val stringRes: Int, @DrawableRes val iconRes: Int) {
     FREE(1, ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED, R.string.rotation_free, R.drawable.ic_screen_rotation_24dp),
@@ -31,9 +31,13 @@ enum class OrientationType(val prefValue: Int, val flag: Int, @StringRes val str
         }
 
         fun getNextOrientation(preference: Int, resources: Resources): OrientationType {
-            // There's only 4 options (1 to 4)
-            val newOrientation = max(1, (preference + 1) % 5)
-            return fromPreference(newOrientation, resources)
+            val current = if (preference == 2) {
+                // Avoid issue due to 2 types having the same prefValue
+                LOCKED_LANDSCAPE
+            } else {
+                fromPreference(preference, resources)
+            }
+            return current.next()
         }
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/reader/setting/ReadingModeType.kt

@@ -2,7 +2,7 @@ package eu.kanade.tachiyomi.ui.reader.setting
 
 import androidx.annotation.StringRes
 import eu.kanade.tachiyomi.R
-import kotlin.math.max
+import eu.kanade.tachiyomi.util.lang.next
 
 enum class ReadingModeType(val prefValue: Int, @StringRes val stringRes: Int) {
     DEFAULT(0, R.string.default_viewer),
@@ -17,9 +17,8 @@ enum class ReadingModeType(val prefValue: Int, @StringRes val stringRes: Int) {
         fun fromPreference(preference: Int): ReadingModeType = values().find { it.prefValue == preference } ?: DEFAULT
 
         fun getNextReadingMode(preference: Int): ReadingModeType {
-            // There's only 6 options (0 to 5)
-            val newReadingMode = max(0, (preference + 1) % 6)
-            return fromPreference(newReadingMode)
+            val current = fromPreference(preference)
+            return current.next()
         }
     }
 }

app/src/main/java/eu/kanade/tachiyomi/util/lang/EnumExtensions.kt

@@ -0,0 +1,7 @@
+package eu.kanade.tachiyomi.util.lang
+
+inline fun <reified T : Enum<T>> T.next(): T {
+    val values = enumValues<T>()
+    val nextOrdinal = (ordinal + 1) % values.size
+    return values[nextOrdinal]
+}