1 files changed, 233 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewPrintDocumentAdapter.java b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewPrintDocumentAdapter.java
new file mode 100644
index 0000000000..806343a637
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewPrintDocumentAdapter.java
@@ -0,0 +1,233 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * vim: ts=4 sw=4 expandtab:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+package org.mozilla.geckoview;
+
+import android.content.Context;
+import android.os.Bundle;
+import android.os.CancellationSignal;
+import android.os.ParcelFileDescriptor;
+import android.print.PageRange;
+import android.print.PrintAttributes;
+import android.print.PrintDocumentAdapter;
+import android.print.PrintDocumentInfo;
+import android.util.Log;
+import androidx.annotation.AnyThread;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import org.mozilla.gecko.util.ThreadUtils;
+
+public class GeckoViewPrintDocumentAdapter extends PrintDocumentAdapter {
+  private static final String LOGTAG = "GVPrintDocumentAdapter";
+  private static final String PRINT_NAME_DEFAULT = "Document";
+  private String mPrintName = PRINT_NAME_DEFAULT;
+  private File mPdfFile;
+  private GeckoResult<File> mGeneratedPdfFile;
+  private Boolean mDoDeleteTmpPdf;
+  private GeckoResult<Boolean> mPrintDialogFinish = null;
+
+  /**
+   * Default GeckoView PrintDocumentAdapter to be used with a PrintManager to print documents using
+   * the default Android print functionality. Will make a temporary PDF file from InputStream.
+   *
+   * @param pdfInputStream an input stream containing a PDF
+   * @param context context that should be used for making a temporary file
+   */
+  public GeckoViewPrintDocumentAdapter(
+      @NonNull final InputStream pdfInputStream, @NonNull final Context context) {
+    this.mDoDeleteTmpPdf = true;
+    this.mGeneratedPdfFile = pdfInputStreamToFile(pdfInputStream, context);
+  }
+
+  /**
+   * GeckoView PrintDocumentAdapter to be used with a PrintManager to print documents using the
+   * default Android print functionality. Will make a temporary PDF file from InputStream.
+   *
+   * @param pdfInputStream an input stream containing a PDF
+   * @param context context that should be used for making a temporary file
+   * @param printDialogFinish result to report that the print finished
+   */
+  public GeckoViewPrintDocumentAdapter(
+      @NonNull final InputStream pdfInputStream,
+      @NonNull final Context context,
+      @Nullable final GeckoResult<Boolean> printDialogFinish) {
+    this.mDoDeleteTmpPdf = true;
+    this.mGeneratedPdfFile = pdfInputStreamToFile(pdfInputStream, context);
+    this.mPrintDialogFinish = printDialogFinish;
+  }
+
+  /**
+   * Default GeckoView PrintDocumentAdapter to be used with a PrintManager to print documents using
+   * the default Android print functionality. Will use existing PDF file for rendering. The filename
+   * may be displayed to users.
+   *
+   * <p>Note: Recommend using other constructor if the PDF file still needs to be created so that
+   * the UI reflects progress.
+   *
+   * @param pdfFile PDF file
+   */
+  public GeckoViewPrintDocumentAdapter(@NonNull final File pdfFile) {
+    this.mPdfFile = pdfFile;
+    this.mDoDeleteTmpPdf = false;
+    this.mPrintName = mPdfFile.getName();
+  }
+
+  /**
+   * Writes the PDF InputStream to a file for the PrintDocumentAdapter to use.
+   *
+   * @param pdfInputStream - InputStream containing a PDF
+   * @param context context that should be used for making a temporary file
+   * @return temporary PDF file
+   */
+  @AnyThread
+  public static @Nullable File makeTempPdfFile(
+      @NonNull final InputStream pdfInputStream, @NonNull final Context context) {
+    File file = null;
+    try {
+      file = File.createTempFile("temp", ".pdf", context.getCacheDir());
+    } catch (final IOException ioe) {
+      Log.e(LOGTAG, "Could not make a file in the cache dir: ", ioe);
+    }
+    final int bufferSize = 8192;
+    final byte[] buffer = new byte[bufferSize];
+    try (final OutputStream out = new BufferedOutputStream(new FileOutputStream(file))) {
+      int len;
+      while ((len = pdfInputStream.read(buffer)) != -1) {
+        out.write(buffer, 0, len);
+      }
+    } catch (final IOException ioe) {
+      Log.e(LOGTAG, "Writing temporary PDF file failed: ", ioe);
+    }
+    return file;
+  }
+
+  /**
+   * Utility to make a PDF file from the input stream in the background.
+   *
+   * @param pdfInputStream - InputStream containing a PDF
+   * @param context context that should be used for making a temporary file
+   * @return gecko result with the file
+   */
+  private @NonNull GeckoResult<File> pdfInputStreamToFile(
+      final @NonNull InputStream pdfInputStream, final @NonNull Context context) {
+    final GeckoResult<File> result = new GeckoResult<>();
+    ThreadUtils.postToBackgroundThread(
+        () -> {
+          result.complete(makeTempPdfFile(pdfInputStream, context));
+        });
+    return result;
+  }
+
+  @Override
+  public void onLayout(
+      final PrintAttributes oldAttributes,
+      final PrintAttributes newAttributes,
+      final CancellationSignal cancellationSignal,
+      final LayoutResultCallback layoutResultCallback,
+      final Bundle bundle) {
+    if (cancellationSignal.isCanceled()) {
+      layoutResultCallback.onLayoutCancelled();
+      return;
+    }
+    final PrintDocumentInfo pdi =
+        new PrintDocumentInfo.Builder(mPrintName)
+            .setContentType(PrintDocumentInfo.CONTENT_TYPE_DOCUMENT)
+            .build();
+    layoutResultCallback.onLayoutFinished(pdi, true);
+  }
+
+  /**
+   * Handles onWrite functionality. Recommend running on a background thread as onWrite is on the
+   * main thread.
+   *
+   * @param pdfFile - PDF file to generate print preview with.
+   * @param parcelFileDescriptor - onWrite parcelFileDescriptor
+   * @param writeResultCallback - onWrite writeResultCallback
+   */
+  private void onWritePdf(
+      final @Nullable File pdfFile,
+      final @NonNull ParcelFileDescriptor parcelFileDescriptor,
+      final @NonNull WriteResultCallback writeResultCallback) {
+    InputStream input = null;
+    OutputStream output = null;
+    try {
+      input = new FileInputStream(pdfFile);
+      output = new FileOutputStream(parcelFileDescriptor.getFileDescriptor());
+      final int bufferSize = 8192;
+      final byte[] buffer = new byte[bufferSize];
+      int bytesRead;
+      while ((bytesRead = input.read(buffer)) > 0) {
+        output.write(buffer, 0, bytesRead);
+      }
+      writeResultCallback.onWriteFinished(new PageRange[] {PageRange.ALL_PAGES});
+    } catch (final Exception ex) {
+      Log.e(LOGTAG, "Could not complete onWrite for printing: ", ex);
+      writeResultCallback.onWriteFailed(null);
+    } finally {
+      try {
+        input.close();
+        output.close();
+      } catch (final Exception ex) {
+        Log.e(LOGTAG, "Could not close i/o stream: ", ex);
+      }
+    }
+  }
+
+  @Override
+  public void onWrite(
+      final PageRange[] pageRanges,
+      final ParcelFileDescriptor parcelFileDescriptor,
+      final CancellationSignal cancellationSignal,
+      final WriteResultCallback writeResultCallback) {
+
+    ThreadUtils.postToBackgroundThread(
+        () -> {
+          if (mGeneratedPdfFile != null) {
+            mGeneratedPdfFile.then(
+                file -> {
+                  if (mPrintName == PRINT_NAME_DEFAULT) {
+                    mPrintName = file.getName();
+                  }
+                  onWritePdf(file, parcelFileDescriptor, writeResultCallback);
+                  return null;
+                });
+          } else {
+            onWritePdf(mPdfFile, parcelFileDescriptor, writeResultCallback);
+          }
+        });
+  }
+
+  @Override
+  public void onFinish() {
+    // Remove the temporary file when the printing system is finished.
+    try {
+      if (mDoDeleteTmpPdf) {
+        if (mPdfFile != null) {
+          mPdfFile.delete();
+        }
+        if (mGeneratedPdfFile != null) {
+          mGeneratedPdfFile.then(
+              file -> {
+                file.delete();
+                return null;
+              });
+        }
+      }
+    } catch (final NullPointerException npe) {
+      // Silence the exception. We only want to delete a real file. We don't
+      // care if the file doesn't exist.
+    }
+    if (this.mPrintDialogFinish != null) {
+      mPrintDialogFinish.complete(true);
+    }
+  }
+}