Option to save/share combined double pages

app/src/main/java/eu/kanade/tachiyomi/ui/base/MaterialMenuSheet.kt

@@ -12,6 +12,7 @@ import android.widget.ImageView
 import android.widget.TextView
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
+import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.core.widget.TextViewCompat
 import com.google.android.material.bottomsheet.BottomSheetBehavior
 import com.google.android.material.bottomsheet.BottomSheetDialog
@@ -52,9 +53,19 @@ open class MaterialMenuSheet(
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O && !context.isInNightMode() && !activity.window.decorView.rootWindowInsets.hasSideNavBar()) {
             window?.decorView?.systemUiVisibility = View.SYSTEM_UI_FLAG_LIGHT_NAVIGATION_BAR
         }
-        maxHeight?.let {
+        if (maxHeight != null) {
-            binding.menuScrollView.maxHeight = it + activity.window.decorView.rootWindowInsets.systemWindowInsetBottom
+            binding.menuScrollView.maxHeight = maxHeight + activity.window.decorView.rootWindowInsets.systemWindowInsetBottom
             binding.menuScrollView.requestLayout()
+        } else {
+            binding.titleLayout.viewTreeObserver.addOnGlobalLayoutListener {
+                binding.menuScrollView.updateLayoutParams<ConstraintLayout.LayoutParams> {
+                    val fullHeight = activity.window.decorView.height
+                    val insets = activity.window.decorView.rootWindowInsets
+                    matchConstraintMaxHeight =
+                        fullHeight - (insets?.systemWindowInsetTop ?: 0) -
+                        binding.titleLayout.height - 26.dpToPx
+                }
+            }
         }
 
         binding.divider.visibleIf(showDivider)

app/src/main/java/eu/kanade/tachiyomi/ui/base/MaxHeightScrollView.kt

@@ -9,11 +9,14 @@ class MaxHeightScrollView @JvmOverloads constructor(context: Context, attrs: Att
     var maxHeight = -1
 
     override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
-        val heightS = if (maxHeight > 0) {
+        var heightS = if (maxHeight > 0) {
             MeasureSpec.makeMeasureSpec(maxHeight, MeasureSpec.AT_MOST)
         } else {
             heightMeasureSpec
         }
+        if (maxHeight < height + (rootWindowInsets?.systemWindowInsetBottom ?: 0)) {
+            heightS = MeasureSpec.makeMeasureSpec(maxHeight, MeasureSpec.AT_MOST)
+        }
         super.onMeasure(widthMeasureSpec, heightS)
     }
 }

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

@@ -968,6 +968,16 @@ class ReaderActivity :
                     2,
                     R.drawable.ic_photo_24dp,
                     R.string.set_first_page_as_cover
+                ),
+                MaterialMenuSheet.MenuSheetItem(
+                    6,
+                    R.drawable.ic_share_all_outline_24dp,
+                    R.string.share_combined_pages
+                ),
+                MaterialMenuSheet.MenuSheetItem(
+                    7,
+                    R.drawable.ic_save_all_outline_24dp,
+                    R.string.save_combined_pages
                 )
             )
         } else {
@@ -997,6 +1007,22 @@ class ReaderActivity :
                 3 -> extraPage?.let { shareImage(it) }
                 4 -> extraPage?.let { saveImage(it) }
                 5 -> extraPage?.let { showSetCoverPrompt(it) }
+                6, 7 -> extraPage?.let { secondPage ->
+                    (viewer as? PagerViewer)?.let { viewer ->
+                        val isLTR = (viewer !is R2LPagerViewer).xor(viewer.config.invertDoublePages)
+                        val bg =
+                            if (viewer.config.readerTheme >= 2 || viewer.config.readerTheme == 0) {
+                                Color.WHITE
+                            } else {
+                                Color.BLACK
+                            }
+                        if (item == 6) {
+                            presenter.shareImages(page, secondPage, isLTR, bg)
+                        } else {
+                            presenter.saveImages(page, secondPage, isLTR, bg)
+                        }
+                    }
+                }
             }
             true
         }.show()
@@ -1051,17 +1077,22 @@ class ReaderActivity :
      * Called from the presenter when a page is ready to be shared. It shows Android's default
      * sharing tool.
      */
-    fun onShareImageResult(file: File, page: ReaderPage) {
+    fun onShareImageResult(file: File, page: ReaderPage, secondPage: ReaderPage? = null) {
         val manga = presenter.manga ?: return
         val chapter = page.chapter.chapter
 
         val decimalFormat =
             DecimalFormat("#.###", DecimalFormatSymbols().apply { decimalSeparator = '.' })
 
+        val pageNumber = if (secondPage != null) {
+            getString(R.string.pages_, if (resources.isLTR) "${page.number}-${page.number + 1}" else "${page.number + 1}-${page.number}")
+        } else {
+            getString(R.string.page_, page.number)
+        }
         val text = "${manga.title}: ${getString(
             R.string.chapter_,
             decimalFormat.format(chapter.chapter_number)
-        )}, ${getString(R.string.page_, page.number)}"
+        )}, $pageNumber"
 
         val stream = file.getUriCompat(this)
         val intent = Intent(Intent.ACTION_SEND).apply {

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

@@ -1,9 +1,11 @@
 package eu.kanade.tachiyomi.ui.reader
 
 import android.app.Application
+import android.graphics.BitmapFactory
 import android.net.Uri
 import android.os.Bundle
 import android.os.Environment
+import androidx.annotation.ColorInt
 import com.jakewharton.rxrelay.BehaviorRelay
 import eu.kanade.tachiyomi.R
 import eu.kanade.tachiyomi.data.cache.CoverCache
@@ -32,8 +34,11 @@ import eu.kanade.tachiyomi.util.chapter.syncChaptersWithSource
 import eu.kanade.tachiyomi.util.storage.DiskUtil
 import eu.kanade.tachiyomi.util.system.ImageUtil
 import eu.kanade.tachiyomi.util.system.executeOnIO
+import eu.kanade.tachiyomi.util.system.withUIContext
+import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import rx.Completable
@@ -117,6 +122,8 @@ class ReaderPresenter(
 
     var chapterItems = emptyList<ReaderChapterItem>()
 
+    private var scope = CoroutineScope(Job() + Dispatchers.Default)
+
     /**
      * Called when the presenter is created. It retrieves the saved active chapter if the process
      * was restored.
@@ -610,6 +617,40 @@ class ReaderPresenter(
         return destFile
     }
 
+    /**
+     * Saves the image of this [page] in the given [directory] and returns the file location.
+     */
+    private fun saveImages(page1: ReaderPage, page2: ReaderPage, isLTR: Boolean, @ColorInt bg: Int, directory: File, manga: Manga): File {
+        val stream1 = page1.stream!!
+        ImageUtil.findImageType(stream1) ?: throw Exception("Not an image")
+        val stream2 = page2.stream!!
+        ImageUtil.findImageType(stream2) ?: throw Exception("Not an image")
+        val imageBytes = stream1().readBytes()
+        val imageBitmap = BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.size)
+
+        val imageBytes2 = stream2().readBytes()
+        val imageBitmap2 = BitmapFactory.decodeByteArray(imageBytes2, 0, imageBytes2.size)
+
+        val stream = ImageUtil.mergeBitmaps(imageBitmap, imageBitmap2, isLTR, bg)
+        directory.mkdirs()
+
+        val chapter = page1.chapter.chapter
+
+        // Build destination file.
+        val filename = DiskUtil.buildValidFilename(
+            "${manga.title} - ${chapter.name}".take(225)
+        ) + " - ${page1.number}-${page2.number}.jpg"
+
+        val destFile = File(directory, filename)
+        stream.use { input ->
+            destFile.outputStream().use { output ->
+                input.copyTo(output)
+            }
+        }
+        stream.close()
+        return destFile
+    }
+
     /**
      * Saves the image of this [page] on the pictures directory and notifies the UI of the result.
      * There's also a notification to allow sharing the image somewhere else or deleting it.
@@ -644,6 +685,34 @@ class ReaderPresenter(
             )
     }
 
+    fun saveImages(firstPage: ReaderPage, secondPage: ReaderPage, isLTR: Boolean, @ColorInt bg: Int) {
+        scope.launch {
+            if (firstPage.status != Page.READY) return@launch
+            if (secondPage.status != Page.READY) return@launch
+            val manga = manga ?: return@launch
+            val context = Injekt.get<Application>()
+
+            val notifier = SaveImageNotifier(context)
+            notifier.onClear()
+
+            // Pictures directory.
+            val destDir = File(
+                Environment.getExternalStorageDirectory().absolutePath +
+                    File.separator + Environment.DIRECTORY_PICTURES +
+                    File.separator + "Tachiyomi"
+            )
+
+            try {
+                val file = saveImages(firstPage, secondPage, isLTR, bg, destDir, manga)
+                DiskUtil.scanMedia(context, file)
+                notifier.onComplete(file)
+                withUIContext { view?.onSaveImageResult(SaveImageResult.Success(file)) }
+            } catch (e: Exception) {
+                withUIContext { view?.onSaveImageResult(SaveImageResult.Error(e)) }
+            }
+        }
+    }
+
     /**
      * Shares the image of this [page] and notifies the UI with the path of the file to share.
      * The image must be first copied to the internal partition because there are many possible
@@ -668,6 +737,25 @@ class ReaderPresenter(
             )
     }
 
+    fun shareImages(firstPage: ReaderPage, secondPage: ReaderPage, isLTR: Boolean, @ColorInt bg: Int) {
+        scope.launch {
+            if (firstPage.status != Page.READY) return@launch
+            if (secondPage.status != Page.READY) return@launch
+            val manga = manga ?: return@launch
+            val context = Injekt.get<Application>()
+
+            val destDir = File(context.cacheDir, "shared_image")
+            destDir.deleteRecursively()
+            try {
+                val file = saveImages(firstPage, secondPage, isLTR, bg, destDir, manga)
+                withUIContext {
+                    view?.onShareImageResult(file, firstPage, secondPage)
+                }
+            } catch (e: Exception) {
+            }
+        }
+    }
+
     /**
      * Sets the image of this [page] as cover and notifies the UI of the result.
      */

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

@@ -3,12 +3,9 @@ package eu.kanade.tachiyomi.ui.reader.viewer.pager
 import android.annotation.SuppressLint
 import android.content.Context
 import android.content.Intent
-import android.graphics.Bitmap
 import android.graphics.BitmapFactory
-import android.graphics.Canvas
 import android.graphics.Color
 import android.graphics.PointF
-import android.graphics.Rect
 import android.graphics.drawable.Drawable
 import android.view.GestureDetector
 import android.view.Gravity
@@ -54,11 +51,8 @@ import rx.Subscription
 import rx.android.schedulers.AndroidSchedulers
 import rx.schedulers.Schedulers
 import uy.kohesive.injekt.injectLazy
-import java.io.ByteArrayInputStream
-import java.io.ByteArrayOutputStream
 import java.io.InputStream
 import java.util.concurrent.TimeUnit
-import kotlin.math.max
 import kotlin.math.roundToInt
 
 /**
@@ -683,36 +677,24 @@ class PagerPageHolder(
             skipExtra = true
             return imageBytes.inputStream()
         }
-
-        val maxHeight = max(height, height2)
-
-        val result = Bitmap.createBitmap(width + width2, max(height, height2), Bitmap.Config.ARGB_8888)
-        val canvas = Canvas(result)
-        canvas.drawColor(if (viewer.config.readerTheme >= 2 || viewer.config.readerTheme == 0) Color.WHITE else Color.BLACK)
         val isLTR = (viewer !is R2LPagerViewer).xor(viewer.config.invertDoublePages)
-        val upperPart = Rect(
+        val bg = if (viewer.config.readerTheme >= 2 || viewer.config.readerTheme == 0) {
-            if (isLTR) 0 else width2,
+            Color.WHITE
-            (maxHeight - imageBitmap.height) / 2,
+        } else {
-            (if (isLTR) 0 else width2) + imageBitmap.width,
+            Color.BLACK
-            imageBitmap.height + (maxHeight - imageBitmap.height) / 2
+        }
-        )
-        canvas.drawBitmap(imageBitmap, imageBitmap.rect, upperPart, null)
-        scope?.launchUI { progressBar.setProgress(98) }
-        val bottomPart = Rect(
-            if (!isLTR) 0 else width,
-            (maxHeight - imageBitmap2.height) / 2,
-            (if (!isLTR) 0 else width) + imageBitmap2.width,
-            imageBitmap2.height + (maxHeight - imageBitmap2.height) / 2
-        )
-        canvas.drawBitmap(imageBitmap2, imageBitmap2.rect, bottomPart, null)
-        scope?.launchUI { progressBar.setProgress(99) }
 
-        val output = ByteArrayOutputStream()
-        result.compress(Bitmap.CompressFormat.JPEG, 100, output)
         imageStream.close()
         imageStream2.close()
-        scope?.launchUI { progressBar.completeAndFadeOut() }
+        return ImageUtil.mergeBitmaps(imageBitmap, imageBitmap2, isLTR, bg) {
-        return ByteArrayInputStream(output.toByteArray())
+            scope?.launchUI {
+                if (it == 100) {
+                    progressBar.completeAndFadeOut()
+                } else {
+                    progressBar.setProgress(it)
+                }
+            }
+        }
     }
 
     private fun splitDoublePages() {
@@ -734,9 +716,6 @@ class PagerPageHolder(
         }
     }
 
-    private val Bitmap.rect: Rect
-        get() = Rect(0, 0, width, height)
-
     companion object {
         fun getBGType(readerTheme: Int, context: Context): Int {
             return if (readerTheme == 3) {

app/src/main/java/eu/kanade/tachiyomi/util/system/ImageUtil.kt

@@ -3,14 +3,20 @@ package eu.kanade.tachiyomi.util.system
 import android.content.Context
 import android.content.res.Configuration
 import android.graphics.Bitmap
+import android.graphics.Canvas
 import android.graphics.Color
+import android.graphics.Rect
 import android.graphics.drawable.ColorDrawable
 import android.graphics.drawable.Drawable
 import android.graphics.drawable.GradientDrawable
+import androidx.annotation.ColorInt
 import eu.kanade.tachiyomi.R
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
 import java.io.InputStream
 import java.net.URLConnection
 import kotlin.math.abs
+import kotlin.math.max
 
 object ImageUtil {
 
@@ -244,6 +250,47 @@ object ImageUtil {
         return ColorDrawable(backgroundColor)
     }
 
+    fun mergeBitmaps(
+        imageBitmap: Bitmap,
+        imageBitmap2: Bitmap,
+        isLTR: Boolean,
+        @ColorInt background: Int = Color.WHITE,
+        progressCallback: ((Int) -> Unit)? = null
+    ): ByteArrayInputStream {
+        val height = imageBitmap.height
+        val width = imageBitmap.width
+        val height2 = imageBitmap2.height
+        val width2 = imageBitmap2.width
+        val maxHeight = max(height, height2)
+        val result = Bitmap.createBitmap(width + width2, max(height, height2), Bitmap.Config.ARGB_8888)
+        val canvas = Canvas(result)
+        canvas.drawColor(background)
+        val upperPart = Rect(
+            if (isLTR) 0 else width2,
+            (maxHeight - imageBitmap.height) / 2,
+            (if (isLTR) 0 else width2) + imageBitmap.width,
+            imageBitmap.height + (maxHeight - imageBitmap.height) / 2
+        )
+        canvas.drawBitmap(imageBitmap, imageBitmap.rect, upperPart, null)
+        progressCallback?.invoke(98)
+        val bottomPart = Rect(
+            if (!isLTR) 0 else width,
+            (maxHeight - imageBitmap2.height) / 2,
+            (if (!isLTR) 0 else width) + imageBitmap2.width,
+            imageBitmap2.height + (maxHeight - imageBitmap2.height) / 2
+        )
+        canvas.drawBitmap(imageBitmap2, imageBitmap2.rect, bottomPart, null)
+        progressCallback?.invoke(99)
+
+        val output = ByteArrayOutputStream()
+        result.compress(Bitmap.CompressFormat.JPEG, 100, output)
+        progressCallback?.invoke(100)
+        return ByteArrayInputStream(output.toByteArray())
+    }
+
+    private val Bitmap.rect: Rect
+        get() = Rect(0, 0, width, height)
+
     fun Boolean.toInt() = if (this) 1 else 0
     private fun isDark(color: Int): Boolean {
         return Color.red(color) < 40 && Color.blue(color) < 40 && Color.green(color) < 40 &&

app/src/main/res/drawable/ic_save_all_outline_24dp.xml

@@ -0,0 +1,9 @@
+<!-- drawable/content_save_all_outline.xml -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:height="24dp"
+    android:width="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/actionBarTintColor">
+    <path android:fillColor="#000" android:pathData="M1 7H3V21H17V23H3C1.9 23 1 22.11 1 21V7M19 1H7C5.89 1 5 1.9 5 3V17C5 18.1 5.89 19 7 19H21C22.1 19 23 18.1 23 17V5L19 1M21 17H7V3H18.17L21 5.83V17M14 10C12.34 10 11 11.34 11 13S12.34 16 14 16 17 14.66 17 13 15.66 10 14 10M8 4H17V8H8V4Z" />
+</vector>

app/src/main/res/drawable/ic_share_all_outline_24dp.xml

@@ -0,0 +1,9 @@
+<!-- drawable/share_all_outline.xml -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:height="24dp"
+    android:width="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/actionBarTintColor">
+    <path android:fillColor="#000" android:pathData="M13 9.8V10.7L11.3 10.9C8.7 11.3 6.8 12.3 5.4 13.6C7.1 13.1 8.9 12.8 11 12.8H13V14.1L15.2 12L13 9.8M11 5L18 12L11 19V14.9C6 14.9 2.5 16.5 0 20C1 15 4 10 11 9M17 8V5L24 12L17 19V16L21 12" />
+</vector>

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

@@ -284,6 +284,7 @@
     <string name="set_as_default_for_all">Set as default for all</string>
     <string name="cover_updated">Cover updated</string>
     <string name="page_">Page %1$d</string>
+    <string name="pages_">Pages %1$s</string>
     <string name="next_chapter_not_found">Next chapter not found</string>
     <string name="decode_image_error">The image could not be decoded</string>
     <string name="use_image_as_cover">Use this image as cover art?</string>
@@ -311,6 +312,9 @@
     <string name="share_second_page">Share second page</string>
     <string name="save_second_page">Save second page</string>
 
+    <string name="share_combined_pages">Share combined pages</string>
+    <string name="save_combined_pages">Save combined pages</string>
+
     <!-- Reader settings -->
     <string name="fullscreen">Fullscreen</string>
     <string name="animate_page_transitions">Animate page transitions</string>