refactor: Refactor PagerPageHolder

app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerPageHolder.kt

@@ -33,11 +33,13 @@ import eu.kanade.tachiyomi.util.system.ImageUtil.isPagePadded
 import eu.kanade.tachiyomi.util.system.ThemeUtil
 import eu.kanade.tachiyomi.util.system.bottomCutoutInset
 import eu.kanade.tachiyomi.util.system.dpToPx
+import eu.kanade.tachiyomi.util.system.e
 import eu.kanade.tachiyomi.util.system.getResourceColor
 import eu.kanade.tachiyomi.util.system.isInNightMode
 import eu.kanade.tachiyomi.util.system.launchIO
 import eu.kanade.tachiyomi.util.system.launchUI
 import eu.kanade.tachiyomi.util.system.topCutoutInset
+import eu.kanade.tachiyomi.util.system.withIOContext
 import eu.kanade.tachiyomi.util.system.withUIContext
 import eu.kanade.tachiyomi.util.view.backgroundColor
 import eu.kanade.tachiyomi.util.view.isVisibleOnScreen
@@ -87,41 +89,12 @@ class PagerPageHolder(
      */
     private var loadJob: Job? = null
 
-    /**
-     * Job for status changes of the page.
-     */
-    private var statusJob: Job? = null
-
-    /**
-     * Job for progress changes of the page.
-     */
-    private var progressJob: Job? = null
-
     /**
      * Job for loading the page.
      */
     private var extraLoadJob: Job? = null
 
-    /**
-     * Job for status changes of the page.
-     */
-    private var extraStatusJob: Job? = null
-
-    /**
-     * Job for progress changes of the page.
-     */
-    private var extraProgressJob: Job? = null
-
-    /**
-     * Job used to read the header of the image. This is needed in order to instantiate
-     * the appropriate image view depending if the image is animated (GIF).
-     */
-    private var readImageHeaderJob: Job? = null
-
     private var status = Page.State.READY
-    private var extraStatus = Page.State.READY
-    private var progress: Int = 0
-    private var extraProgress: Int = 0
 
     private var scope = MainScope()
 
@@ -190,12 +163,12 @@ class PagerPageHolder(
      */
     override fun onDetachedFromWindow() {
         super.onDetachedFromWindow()
+
         loadJob?.cancel()
         loadJob = null
         extraLoadJob?.cancel()
         extraLoadJob = null
 
-        cancelReadImageHeader()
         (pageView as? SubsamplingScaleImageView)?.setOnImageEventListener(null)
     }
 
@@ -334,14 +307,6 @@ class PagerPageHolder(
         }
     }
 
-    /**
-     * Unsubscribes from the read image header subscription.
-     */
-    private fun cancelReadImageHeader() {
-        readImageHeaderJob?.cancel()
-        readImageHeaderJob = null
-    }
-
     /**
      * Called when the page is queued.
      */
@@ -369,7 +334,7 @@ class PagerPageHolder(
     /**
      * Called when the page is ready.
      */
-    private fun setImage() {
+    private suspend fun setImage() {
         progressBar.isVisible = true
         if (extraPage == null) {
             progressBar.completeAndFadeOut()
@@ -378,59 +343,60 @@ class PagerPageHolder(
         }
         errorLayout?.isVisible = false
 
-        cancelReadImageHeader()
+        val streamFn = page.stream ?: return
-
-        readImageHeaderJob = scope.launchIO {
-            val streamFn = page.stream ?: return@launchIO
         val streamFn2 = extraPage?.stream
 
-            var actualSource: BufferedSource? = null
         try {
-                val source1 = streamFn().buffered(16).use { Buffer().readFrom(it) }
+            val (source, isAnimated, _bg) = withIOContext {
-                val source2 = streamFn2?.invoke()?.buffered(16)?.use { Buffer().readFrom(it) }
+                streamFn().buffered(16).use { source1 ->
+                    if (extraPage != null) {
+                        streamFn2?.invoke()
+                            ?.buffered(16)
+                    } else {
+                        null
+                    }.use { source2 ->
+                        val actualSource = this@PagerPageHolder.mergeOrSplitPages(
+                            Buffer().readFrom(source1),
+                            source2?.let { Buffer().readFrom(it) },
+                        )
 
-                actualSource = this@PagerPageHolder.mergeOrSplitPages(source1, source2)
+                        val isAnimated = ImageUtil.isAnimatedAndSupported(actualSource)
-                val isAnimated = ImageUtil.isAnimatedAndSupported(source1) ||
-                    (source2?.let { ImageUtil.isAnimatedAndSupported(source2) } ?: false)
-                withUIContext {
                         val bgColor = ReaderBackgroundColor.fromPreference(viewer.config.readerTheme)
-                    if (!isAnimated) {
-                        if (bgColor.isSmartColor) {
                         val bgType = getBGType(viewer.config.readerTheme, context)
-                            if (page.bg != null && page.bgType == bgType) {
+                        val background = if (!isAnimated && bgColor.isSmartColor) {
-                                setImage(actualSource, false, imageConfig)
+                            if (page.bg != null && page.bgType == bgType) page.bg
-                                pageView?.background = page.bg
-                            }
-                            // if the user switches to automatic when pages are already cached, the bg needs to be loaded
                             else {
-                                val background =
                                 try {
                                     setBG(actualSource.peek().inputStream())
                                 } catch (e: Exception) {
                                     Logger.e(e) { e.localizedMessage?.toString() ?: "" }
                                     ColorDrawable(Color.WHITE)
                                 }
-                                setImage(actualSource, false, imageConfig)
+                            }
+                        } else if (bgColor.isSmartColor && page.bg != null) {
+                            page.bg
+                        } else {
+                            null
+                        }
 
-                                pageView?.background = background
+                        Triple(actualSource, isAnimated, Pair(background, bgType))
+                    }
+                }
+            }
+
+            withUIContext {
+                val (bg, bgType) = _bg
+                if (bg != null) pageView?.background = bg
+                if (!isAnimated && page.bg == null && page.bgType != bgType) {
                     page.bg = pageView?.background
                     page.bgType = bgType
                 }
-                        } else {
+                setImage(source, isAnimated, imageConfig)
-                            setImage(actualSource, false, imageConfig)
-                        }
-                    } else {
-                        setImage(actualSource, true, imageConfig)
-                        if (bgColor.isSmartColor && page.bg != null) {
-                            pageView?.background = page.bg
-                        }
-                    }
-                }
-            } catch (_: Exception) {
-                try {
-                    actualSource?.let { closeSources(it) }
-                } catch (_: Exception) {
             }
+        } catch (e: Exception) {
+            Logger.e(e)
+            withUIContext {
+                setError()
             }
         }
     }