Migrate five classes to Kotlin. https://redmine.stoutner.com/issues/950

[PrivacyBrowserAndroid.git] / app / src / main / java / com / stoutner / privacybrowser / coroutines / SaveWebpageImageCoroutine.kt

diff --git a/app/src/main/java/com/stoutner/privacybrowser/coroutines/SaveWebpageImageCoroutine.kt b/app/src/main/java/com/stoutner/privacybrowser/coroutines/SaveWebpageImageCoroutine.kt
new file mode 100644 (file)
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+++ b/app/src/main/java/com/stoutner/privacybrowser/coroutines/SaveWebpageImageCoroutine.kt
@@ -0,0 +1,122 @@
+/*
+ * Copyright0 2019-2023 Soren Stoutner <soren@stoutner.com>.
+ *
+ * This file is part of Privacy Browser Android <https://www.stoutner.com/privacy-browser-android>.
+ *
+ * Privacy Browser Android is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Privacy Browser Android is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Privacy Browser Android.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.stoutner.privacybrowser.coroutines
+
+import android.app.Activity
+import android.graphics.Bitmap
+import android.graphics.Canvas
+import android.net.Uri
+import android.os.Build
+import android.provider.OpenableColumns
+
+import com.google.android.material.snackbar.Snackbar
+
+import com.stoutner.privacybrowser.R
+import com.stoutner.privacybrowser.views.NestedScrollWebView
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+
+import java.io.ByteArrayOutputStream
+
+class SaveWebpageImageCoroutine {
+    fun save(activity: Activity, fileUri: Uri, nestedScrollWebView: NestedScrollWebView) {
+        // Use a coroutine to save the webpage image.
+        CoroutineScope(Dispatchers.Main).launch {
+            // Create a file name string.
+            val fileNameString: String
+
+            // Query the exact file name if the API >= 26.
+            if (Build.VERSION.SDK_INT >= 26) {
+                // Get a cursor from the content resolver.
+                val contentResolverCursor = activity.contentResolver.query(fileUri, null, null, null)
+
+                // Move to the first row.
+                contentResolverCursor!!.moveToFirst()
+
+                // Get the file name from the cursor.
+                fileNameString = contentResolverCursor.getString(contentResolverCursor.getColumnIndexOrThrow(OpenableColumns.DISPLAY_NAME))
+
+                // Close the cursor.
+                contentResolverCursor.close()
+            } else {
+                // Use the file URI last path segment as the file name string.
+                fileNameString = fileUri.lastPathSegment!!
+            }
+
+            // Create a saving image snackbar.
+            val savingImageSnackbar = Snackbar.make(nestedScrollWebView, activity.getString(R.string.processing_image, fileNameString), Snackbar.LENGTH_INDEFINITE)
+
+            // Display the saving image snackbar.
+            savingImageSnackbar.show()
+
+            // Create a webpage bitmap.  Once the Minimum API >= 26 Bitmap.Config.RBGA_F16 can be used instead of ARGB_8888.  The nested scroll WebView commands must be run on the UI thread.
+            val webpageBitmap = Bitmap.createBitmap(nestedScrollWebView.getHorizontalScrollRange(), nestedScrollWebView.getVerticalScrollRange(), Bitmap.Config.ARGB_8888)
+
+            // Create a canvas.
+            val webpageCanvas = Canvas(webpageBitmap)
+
+            // Draw the current webpage onto the bitmap.  The nested scroll WebView commands must be run on the UI thread.
+            nestedScrollWebView.draw(webpageCanvas)
+
+            // Compress the image on the IO thread.
+            withContext(Dispatchers.IO) {
+                // Create a webpage PNG byte array output stream.
+                val webpageByteArrayOutputStream = ByteArrayOutputStream()
+
+                // Convert the bitmap to a PNG.  `0` is for lossless compression (the only option for a PNG).  This compression takes a long time.
+                // Once the minimum API >= 30 this could be replaced with WEBP_LOSSLESS.
+                webpageBitmap.compress(Bitmap.CompressFormat.PNG, 0, webpageByteArrayOutputStream)
+
+                try {
+                    // Create an image file output stream.
+                    val imageFileOutputStream = activity.contentResolver.openOutputStream(fileUri)!!
+
+                    // Write the webpage image to the image file.
+                    webpageByteArrayOutputStream.writeTo(imageFileOutputStream)
+
+                    // Close the output stream.
+                    imageFileOutputStream.close()
+
+                    // Update the UI.
+                    withContext(Dispatchers.Main) {
+                        // Dismiss the saving image snackbar.
+                        savingImageSnackbar.dismiss()
+
+                        // Display the image saved snackbar.
+                        Snackbar.make(nestedScrollWebView, activity.getString(R.string.saved, fileNameString), Snackbar.LENGTH_SHORT).show()
+                    }
+                } catch (exception: Exception) {
+                    // Update the UI.
+                    withContext(Dispatchers.Main) {
+                        // Dismiss the saving image snackbar.
+                        savingImageSnackbar.dismiss()
+
+                        // Display the file saving error.
+                        Snackbar.make(nestedScrollWebView, activity.getString(R.string.error_saving_file, fileNameString, exception), Snackbar.LENGTH_INDEFINITE).show()
+                    }
+                }
+
+            }
+        }
+    }
+}
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