.github/dependabot.yml

@@ -0,0 +1,12 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: daily
+    target-branch: main
+  - package-ecosystem: gradle
+    directory: "/"
+    schedule:
+      interval: daily
+    target-branch: main

.github/workflows/build.yml

@@ -0,0 +1,20 @@
+name: Build application
+
+on: [pull_request, push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: true
+      - name: Set up JDK 19
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: 19
+          cache: gradle
+      - name: Build with Gradle
+        run: ./gradlew build --no-daemon

.github/workflows/validate-gradle-wrapper.yml

@@ -0,0 +1,11 @@
+name: Validate Gradle Wrapper
+
+on: [pull_request, push]
+
+jobs:
+  validation:
+    name: Validation
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: gradle/wrapper-validation-action@v1

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "pdfjs-dist"]
+	path = app/pdfjs-dist
+	url = https://github.com/mozilla/pdfjs-dist.git

LICENSE

@@ -1,4 +1,4 @@
-Copyright © 2017-2023 GrapheneOS
+Copyright © 2017-2022 GrapheneOS
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,6 +1,11 @@
-Fork of GrapheneOS' [PdfViewer](https://github.com/GrapheneOS/PdfViewer) to work as a library.
-
-## Warning !
-The only goal of this library is to be integrated in [DroidFS](https://forge.chapril.org/hardcoresushi/DroidFS). Use it at your own risk !
-
-The npm dependency has been removed. Instead, `pdf.min.js` and `pdf.worker.min.js` must be manually placed in `app/pdfjs-dist/build/`.
+Simple Android PDF viewer based on pdf.js and content providers. The app
+doesn't require any permissions. The PDF stream is fed into the sandboxed
+WebView without giving it access to content or files. Content-Security-Policy
+is used to enforce that the JavaScript and styling properties within the
+WebView are entirely static content from the apk assets. It reuses the hardened
+Chromium rendering stack while only exposing a tiny subset of the attack
+surface compared to actual web content. The PDF rendering code itself is memory
+safe with dynamic code evaluation disabled, and even if an attacker did gain
+code execution by exploiting the underlying web rendering engine, they're
+within the Chromium renderer sandbox with no access to the network (unlike a
+browser), files, or other content.

app/build.gradle.kts

@@ -13,12 +13,6 @@ plugins {
     id("kotlin-android")
 }
 
-java {
-    toolchain {
-        languageVersion.set(JavaLanguageVersion.of(17))
-    }
-}
-
 android {
     if (useKeystoreProperties) {
         signingConfigs {
@@ -39,7 +33,7 @@ android {
     }
 
     compileSdk = 33
-    buildToolsVersion = "33.0.2"
+    buildToolsVersion = "33.0.0"
 
     namespace = "app.grapheneos.pdfviewer"
 
@@ -67,21 +61,20 @@ android {
 
         buildFeatures {
             viewBinding = true
-            buildConfig = true
         }
     }
 
     compileOptions {
-        sourceCompatibility(JavaVersion.VERSION_17)
-        targetCompatibility(JavaVersion.VERSION_17)
+        sourceCompatibility(JavaVersion.VERSION_11)
+        targetCompatibility(JavaVersion.VERSION_11)
     }
 
     kotlinOptions {
-        jvmTarget = JavaVersion.VERSION_17.toString()
+        jvmTarget = JavaVersion.VERSION_11.toString()
     }
 }
 
 dependencies {
-    implementation("androidx.appcompat:appcompat:1.6.1")
-    implementation("com.google.android.material:material:1.9.0")
+    implementation("androidx.appcompat:appcompat:1.5.1")
+    implementation("com.google.android.material:material:1.7.0")
 }

app/src/main/assets/viewer.css

@@ -1,8 +1,3 @@
-:root {
-    --text-layer-opacity: 0.2;
-    --text-layer-foreground: transparent;
-}
-
 html, body {
     height: 100%;
 }
@@ -17,8 +12,6 @@ body {
 }
 
 #container {
-    --scale-factor: 1;
-
     width: 100%;
     height: 100%;
     display: grid;
@@ -31,26 +24,25 @@ body {
     grid-column-start: 1;
 }
 
-canvas {
+canvas, .textLayer {
     display: inline-block;
     position: relative;
 }
 
 .textLayer {
     text-align: initial;
-    position: absolute;
     overflow: hidden;
-    opacity: var(--text-layer-opacity);
+    opacity: 0.2;
     line-height: 1;
 }
 
 .textLayer span,
 .textLayer br {
-    color: var(--text-layer-foreground);
+    color: transparent;
     position: absolute;
     white-space: pre;
     cursor: text;
-    transform-origin: 0 0;
+    transform-origin: 0% 0%;
 }
 
 .textLayer .highlight {
@@ -99,13 +91,3 @@ canvas {
 .textLayer .endOfContent.active {
     top: 0;
 }
-
-[data-main-rotation="90"] {
-    transform: rotate(90deg);
-}
-[data-main-rotation="180"] {
-    transform: rotate(180deg);
-}
-[data-main-rotation="270"] {
-    transform: rotate(270deg);
-}

app/src/main/assets/viewer.js

@@ -6,8 +6,7 @@ let pdfDoc = null;
 let pageRendering = false;
 let renderPending = false;
 let renderPendingZoom = 0;
-const canvas = document.getElementById("content");
-const container = document.getElementById("container");
+const canvas = document.getElementById('content');
 let orientationDegrees = 0;
 let zoomRatio = 1;
 let textLayerDiv = document.getElementById("text");
@@ -20,8 +19,6 @@ let useRender;
 const cache = [];
 const maxCached = 6;
 
-let isTextLayerVisible = false;
-
 function maybeRenderNextPage() {
     if (renderPending) {
         pageRendering = false;
@@ -64,21 +61,6 @@ function display(newCanvas, zoom) {
     }
 }
 
-function setLayerTransform(pageWidth, pageHeight, layerDiv) {
-    const translate = {
-        X: Math.max(0, pageWidth - document.body.clientWidth) / 2,
-        Y: Math.max(0, pageHeight - document.body.clientHeight) / 2
-    };
-    layerDiv.style.translate = `${translate.X}px ${translate.Y}px`;
-}
-
-function getDefaultZoomRatio(page, orientationDegrees) {
-    const viewport = page.getViewport({scale: 1, rotation: orientationDegrees});
-    const widthZoomRatio = document.body.clientWidth / viewport.width;
-    const heightZoomRatio = document.body.clientHeight / viewport.height;
-    return Math.max(Math.min(widthZoomRatio, heightZoomRatio, channel.getMaxZoomRatio()), channel.getMinZoomRatio());
-}
-
 function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
     pageRendering = true;
     useRender = !prerender;
@@ -100,8 +82,6 @@ function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
 
                 textLayerDiv.replaceWith(cached.textLayerDiv);
                 textLayerDiv = cached.textLayerDiv;
-                setLayerTransform(cached.pageWidth, cached.pageHeight, textLayerDiv);
-                container.style.setProperty("--scale-factor", newZoomRatio.toString());
             }
 
             pageRendering = false;
@@ -115,15 +95,7 @@ function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
             return;
         }
 
-        const defaultZoomRatio = getDefaultZoomRatio(page, orientationDegrees);
-
-        if (cache.length === 0) {
-            zoomRatio = defaultZoomRatio;
-            newZoomRatio = defaultZoomRatio;
-            channel.setZoomRatio(defaultZoomRatio);
-        }
-
-        const viewport = page.getViewport({scale: newZoomRatio, rotation: orientationDegrees});
+        const viewport = page.getViewport({scale: newZoomRatio, rotation: orientationDegrees})
 
         if (useRender) {
             if (newZoomRatio !== zoomRatio) {
@@ -133,7 +105,7 @@ function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
             zoomRatio = newZoomRatio;
         }
 
-        if (zoom === 2) {
+        if (zoom == 2) {
             pageRendering = false;
             return;
         }
@@ -165,10 +137,10 @@ function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
             }
             render();
 
-            const newTextLayerDiv = textLayerDiv.cloneNode();
+            const textLayerFrag = document.createDocumentFragment();
             task = pdfjsLib.renderTextLayer({
-                textContentSource: page.streamTextContent(),
-                container: newTextLayerDiv,
+                textContentStream: page.streamTextContent(),
+                container: textLayerFrag,
                 viewport: viewport
             });
             task.promise.then(function() {
@@ -176,36 +148,24 @@ function renderPage(pageNumber, zoom, prerender, prerenderTrigger=0) {
 
                 render();
 
-                // We use CSS transform to rotate a text layer div of zero
-                // degrees rotation. So, when the rotation is 90 or 270
-                // degrees, set width and height of the text layer div to the
-                // height and width of the canvas, respectively, to prevent
-                // text layer misalignment.
-                if (orientationDegrees % 180 === 0) {
-                    newTextLayerDiv.style.height = newCanvas.style.height;
-                    newTextLayerDiv.style.width = newCanvas.style.width;
-                } else {
-                    newTextLayerDiv.style.height = newCanvas.style.width;
-                    newTextLayerDiv.style.width = newCanvas.style.height;
-                }
-                setLayerTransform(viewport.width, viewport.height, newTextLayerDiv);
+                const newTextLayerDiv = textLayerDiv.cloneNode();
+                newTextLayerDiv.style.height = newCanvas.style.height;
+                newTextLayerDiv.style.width = newCanvas.style.width;
                 if (useRender) {
                     textLayerDiv.replaceWith(newTextLayerDiv);
                     textLayerDiv = newTextLayerDiv;
-                    container.style.setProperty("--scale-factor", newZoomRatio.toString());
                 }
+                newTextLayerDiv.appendChild(textLayerFrag);
 
                 if (cache.length === maxCached) {
-                    cache.shift();
+                    cache.shift()
                 }
                 cache.push({
                     pageNumber: pageNumber,
                     zoomRatio: newZoomRatio,
                     orientationDegrees: orientationDegrees,
                     canvas: newCanvas,
-                    textLayerDiv: newTextLayerDiv,
-                    pageWidth: viewport.width,
-                    pageHeight: viewport.height
+                    textLayerDiv: newTextLayerDiv
                 });
 
                 pageRendering = false;
@@ -238,18 +198,6 @@ function isTextSelected() {
     return window.getSelection().toString() !== "";
 }
 
-function toggleTextLayerVisibility() {
-    let textLayerForeground = "red";
-    let textLayerOpacity = 1;
-    if (isTextLayerVisible) {
-        textLayerForeground = "transparent";
-        textLayerOpacity = 0.2;
-    }
-    document.documentElement.style.setProperty("--text-layer-foreground", textLayerForeground);
-    document.documentElement.style.setProperty("--text-layer-opacity", textLayerOpacity.toString());
-    isTextLayerVisible = !isTextLayerVisible;
-}
-
 function loadDocument() {
     const pdfPassword = channel.getPassword();
     const loadingTask = pdfjsLib.getDocument({ url: "https://localhost/placeholder.pdf", password: pdfPassword });
@@ -259,7 +207,7 @@ function loadDocument() {
         } else if (error === pdfjsLib.PasswordResponses.INCORRECT_PASSWORD) {
             channel.invalidPassword();
         }
-    };
+    }
 
     loadingTask.promise.then(function (newDoc) {
         channel.onLoaded();
@@ -275,7 +223,3 @@ function loadDocument() {
         console.error(reason.name + ": " + reason.message);
     });
 }
-
-window.onresize = () => {
-    setLayerTransform(canvas.clientWidth, canvas.clientHeight, textLayerDiv);
-};

app/src/main/java/app/grapheneos/pdfviewer/PdfViewer.java

@@ -42,14 +42,12 @@ import app.grapheneos.pdfviewer.fragment.DocumentPropertiesFragment;
 import app.grapheneos.pdfviewer.fragment.PasswordPromptFragment;
 import app.grapheneos.pdfviewer.fragment.JumpToPageFragment;
 import app.grapheneos.pdfviewer.ktx.ViewKt;
-import app.grapheneos.pdfviewer.loader.DocumentPropertiesAsyncTaskLoader;
+import app.grapheneos.pdfviewer.loader.DocumentPropertiesLoader;
 import app.grapheneos.pdfviewer.viewModel.PasswordStatus;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 
@@ -57,7 +55,7 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
     public static final String TAG = "PdfViewer";
 
     private static final String KEY_PROPERTIES = "properties";
-    private static final int MIN_WEBVIEW_RELEASE = 92;
+    private static final int MIN_WEBVIEW_RELEASE = 89;
 
     private static final String CONTENT_SECURITY_POLICY =
         "default-src 'none'; " +
@@ -100,7 +98,7 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
         "usb=(), " +
         "xr-spatial-tracking=()";
 
-    private static final float MIN_ZOOM_RATIO = 0.2f;
+    private static final float MIN_ZOOM_RATIO = 0.5f;
     private static final float MAX_ZOOM_RATIO = 1.5f;
     private static final int ALPHA_LOW = 130;
     private static final int ALPHA_HIGH = 255;
@@ -138,21 +136,6 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
             return mZoomRatio;
         }
 
-        @JavascriptInterface
-        public void setZoomRatio(final float ratio) {
-            mZoomRatio = Math.max(Math.min(ratio, MAX_ZOOM_RATIO), MIN_ZOOM_RATIO);
-        }
-
-        @JavascriptInterface
-        public float getMinZoomRatio() {
-            return MIN_ZOOM_RATIO;
-        }
-
-        @JavascriptInterface
-        public float getMaxZoomRatio() {
-            return MAX_ZOOM_RATIO;
-        }
-
         @JavascriptInterface
         public int getDocumentOrientationDegrees() {
             return mDocumentOrientationDegrees;
@@ -172,7 +155,7 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
 
             final Bundle args = new Bundle();
             args.putString(KEY_PROPERTIES, properties);
-            activity.runOnUiThread(() -> LoaderManager.getInstance(PdfViewer.this.activity).restartLoader(DocumentPropertiesAsyncTaskLoader.ID, args, PdfViewer.this));
+            activity.runOnUiThread(() -> LoaderManager.getInstance(PdfViewer.this.activity).restartLoader(DocumentPropertiesLoader.ID, args, PdfViewer.this));
         }
 
         @JavascriptInterface
@@ -371,15 +354,6 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
         return mPasswordPromptFragment;
     }
 
-    private void setToolbarTitleWithDocumentName() {
-        String documentName = getCurrentDocumentName();
-        if (documentName != null && !documentName.isEmpty()) {
-            activity.getSupportActionBar().setTitle(documentName);
-        } else {
-            activity.getSupportActionBar().setTitle(R.string.app_name);
-        }
-    }
-
     public void onResume() {
         // The user could have left the activity to update the WebView
         activity.invalidateOptionsMenu();
@@ -405,14 +379,13 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
     @NonNull
     @Override
     public Loader<List<CharSequence>> onCreateLoader(int id, Bundle args) {
-        return new DocumentPropertiesAsyncTaskLoader(activity, args.getString(KEY_PROPERTIES), mNumPages, fileName, fileSize);
+        return new DocumentPropertiesLoader(activity, args.getString(KEY_PROPERTIES), mNumPages, fileName, fileSize);
     }
 
     @Override
     public void onLoadFinished(@NonNull Loader<List<CharSequence>> loader, List<CharSequence> data) {
         mDocumentProperties = data;
-        setToolbarTitleWithDocumentName();
-        LoaderManager.getInstance(activity).destroyLoader(DocumentPropertiesAsyncTaskLoader.ID);
+        LoaderManager.getInstance(activity).destroyLoader(DocumentPropertiesLoader.ID);
     }
 
     @Override
@@ -512,19 +485,12 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
     public void onCreateOptionMenu(@NonNull Menu menu) {
         MenuInflater inflater = activity.getMenuInflater();
         inflater.inflate(R.menu.pdf_viewer, menu);
-        if (BuildConfig.DEBUG) {
-            inflater.inflate(R.menu.pdf_viewer_debug, menu);
-        }
     }
 
     public boolean onPrepareOptionsMenu(@NonNull Menu menu) {
-        final ArrayList<Integer> ids = new ArrayList<>(Arrays.asList(R.id.action_jump_to_page,
-                R.id.action_next, R.id.action_previous, R.id.action_first, R.id.action_last,
-                R.id.action_rotate_clockwise, R.id.action_rotate_counterclockwise,
-                R.id.action_view_document_properties));
-        if (BuildConfig.DEBUG) {
-            ids.add(R.id.debug_action_toggle_text_layer_visibility);
-        }
+        final int[] ids = {R.id.action_jump_to_page, R.id.action_next, R.id.action_previous,
+                R.id.action_first, R.id.action_last, R.id.action_rotate_clockwise,
+                R.id.action_rotate_counterclockwise, R.id.action_view_document_properties};
         if (mDocumentState < STATE_LOADED) {
             for (final int id : ids) {
                 final MenuItem item = menu.findItem(id);
@@ -574,29 +540,10 @@ public class PdfViewer implements LoaderManager.LoaderCallbacks<List<CharSequenc
                 .show(activity.getSupportFragmentManager(), DocumentPropertiesFragment.TAG);
             return true;
         } else if (itemId == R.id.action_jump_to_page) {
-            new JumpToPageFragment(this)
+            JumpToPageFragment.newInstance(this)
                 .show(activity.getSupportFragmentManager(), JumpToPageFragment.TAG);
             return true;
-        } else if (itemId == R.id.debug_action_toggle_text_layer_visibility) {
-            binding.webview.evaluateJavascript("toggleTextLayerVisibility()", null);
-            return true;
         }
-
         return false;
     }
-
-    private String getCurrentDocumentName() {
-        if (mDocumentProperties == null || mDocumentProperties.isEmpty()) return "";
-        String fileName = "";
-        String title = "";
-        for (CharSequence property : mDocumentProperties) {
-            if (property.toString().startsWith("File name:")) {
-                fileName = property.toString().replace("File name:", "");
-            }
-            if (property.toString().startsWith("Title:-")) {
-                title = property.toString().replace("Title:-", "");
-            }
-        }
-        return fileName.length() > 2 ? fileName : title;
-    }
 }

app/src/main/java/app/grapheneos/pdfviewer/Utils.java

@@ -9,6 +9,21 @@ import java.text.ParseException;
 import java.util.Calendar;
 
 public class Utils {
+    public static String parseFileSize(long fileSize) {
+        final double kb = fileSize / 1000d;
+
+        if (kb == 0d) {
+            return fileSize + " Bytes";
+        }
+
+        final DecimalFormat format = new DecimalFormat("#.##");
+        format.setRoundingMode(RoundingMode.CEILING);
+
+        if (kb < 1000) {
+            return format.format(kb) + " kB (" + fileSize + " Bytes)";
+        }
+        return format.format(kb / 1000) + " MB (" + fileSize + " Bytes)";
+    }
 
     private static int parseIntSafely(String field) throws ParseException  {
         try {

app/src/main/java/app/grapheneos/pdfviewer/fragment/DocumentPropertiesFragment.java

@@ -0,0 +1,60 @@
+package app.grapheneos.pdfviewer.fragment;
+
+import android.app.Activity;
+import android.app.Dialog;
+import android.os.Bundle;
+import android.widget.ArrayAdapter;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.DialogFragment;
+
+import com.google.android.material.dialog.MaterialAlertDialogBuilder;
+
+import app.grapheneos.pdfviewer.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class DocumentPropertiesFragment extends DialogFragment {
+    public static final String TAG = "DocumentPropertiesFragment";
+
+    private static final String KEY_DOCUMENT_PROPERTIES = "document_properties";
+
+    private List<String> mDocumentProperties;
+
+    public static DocumentPropertiesFragment newInstance(final List<CharSequence> metaData) {
+        final DocumentPropertiesFragment fragment = new DocumentPropertiesFragment();
+        final Bundle args = new Bundle();
+
+        args.putCharSequenceArrayList(KEY_DOCUMENT_PROPERTIES, (ArrayList<CharSequence>) metaData);
+        fragment.setArguments(args);
+
+        return fragment;
+    }
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        if (getArguments() != null) {
+            mDocumentProperties = getArguments().getStringArrayList(KEY_DOCUMENT_PROPERTIES);
+        }
+    }
+
+    @NonNull
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        final Activity activity = requireActivity();
+        final MaterialAlertDialogBuilder dialog = new MaterialAlertDialogBuilder(activity)
+                .setPositiveButton(android.R.string.ok, null);
+
+        if (mDocumentProperties != null) {
+            dialog.setTitle(getString(R.string.action_view_document_properties));
+            dialog.setAdapter(new ArrayAdapter<>(activity, android.R.layout.simple_list_item_1,
+                    mDocumentProperties), null);
+        } else {
+            dialog.setTitle(R.string.document_properties_retrieval_failed);
+        }
+        return dialog.create();
+    }
+}

app/src/main/java/app/grapheneos/pdfviewer/fragment/DocumentPropertiesFragment.kt

@@ -1,53 +0,0 @@
-package app.grapheneos.pdfviewer.fragment
-
-import android.app.Dialog
-import android.os.Bundle
-import android.widget.ArrayAdapter
-import androidx.fragment.app.DialogFragment
-import app.grapheneos.pdfviewer.R
-import com.google.android.material.dialog.MaterialAlertDialogBuilder
-
-class DocumentPropertiesFragment : DialogFragment() {
-
-    // TODO replace with nav args once the `PdfViewer` activity is converted to kotlin
-    private val mDocumentProperties: List<String> by lazy {
-        requireArguments().getStringArrayList(KEY_DOCUMENT_PROPERTIES)?.toList() ?: emptyList()
-    }
-
-    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
-        return MaterialAlertDialogBuilder(requireActivity())
-            .setPositiveButton(android.R.string.ok, null).apply {
-                if (mDocumentProperties.isNotEmpty()) {
-                    setTitle(getString(R.string.action_view_document_properties))
-                    setAdapter(
-                        ArrayAdapter(
-                            requireActivity(),
-                            android.R.layout.simple_list_item_1,
-                            mDocumentProperties
-                        ), null
-                    )
-                } else {
-                    setTitle(R.string.document_properties_retrieval_failed)
-                }
-            }
-            .create()
-    }
-
-    companion object {
-
-        const val TAG = "DocumentPropertiesFragment"
-        private const val KEY_DOCUMENT_PROPERTIES = "document_properties"
-
-        @JvmStatic
-        fun newInstance(metaData: List<CharSequence>): DocumentPropertiesFragment {
-            val fragment = DocumentPropertiesFragment()
-            val args = Bundle()
-            args.putCharSequenceArrayList(
-                KEY_DOCUMENT_PROPERTIES,
-                metaData as ArrayList<CharSequence>
-            )
-            fragment.arguments = args
-            return fragment
-        }
-    }
-}

app/src/main/java/app/grapheneos/pdfviewer/fragment/JumpToPageFragment.java

@@ -0,0 +1,62 @@
+package app.grapheneos.pdfviewer.fragment;
+
+import android.app.Dialog;
+import android.os.Bundle;
+import android.view.Gravity;
+import android.widget.FrameLayout;
+import android.widget.NumberPicker;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.DialogFragment;
+
+import com.google.android.material.dialog.MaterialAlertDialogBuilder;
+
+import app.grapheneos.pdfviewer.PdfViewer;
+
+public class JumpToPageFragment extends DialogFragment {
+    public static final String TAG = "JumpToPageFragment";
+
+    private final static String STATE_PICKER_CUR = "picker_cur";
+    private final static String STATE_PICKER_MIN = "picker_min";
+    private final static String STATE_PICKER_MAX = "picker_max";
+
+    private NumberPicker mPicker;
+    PdfViewer pdfViewer;
+
+    public static JumpToPageFragment newInstance(PdfViewer pdfViewer) {
+        JumpToPageFragment f = new JumpToPageFragment();
+        f.pdfViewer = pdfViewer;
+        return f;
+    }
+
+    @NonNull
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        mPicker = new NumberPicker(getActivity());
+        mPicker.setMinValue(1);
+        mPicker.setMaxValue(pdfViewer.mNumPages);
+        mPicker.setValue(pdfViewer.mPage);
+
+        final FrameLayout layout = new FrameLayout(getActivity());
+        layout.addView(mPicker, new FrameLayout.LayoutParams(
+                FrameLayout.LayoutParams.WRAP_CONTENT,
+                FrameLayout.LayoutParams.WRAP_CONTENT,
+                Gravity.CENTER));
+
+        return new MaterialAlertDialogBuilder(requireActivity())
+                .setView(layout)
+                .setPositiveButton(android.R.string.ok, (dialogInterface, i) -> {
+                    mPicker.clearFocus();
+                    pdfViewer.onJumpToPageInDocument(mPicker.getValue());
+                })
+                .setNegativeButton(android.R.string.cancel, null)
+                .create();
+    }
+
+    @Override
+    public void onSaveInstanceState(Bundle outState) {
+        outState.putInt(STATE_PICKER_MIN, mPicker.getMinValue());
+        outState.putInt(STATE_PICKER_MAX, mPicker.getMaxValue());
+        outState.putInt(STATE_PICKER_CUR, mPicker.getValue());
+    }
+}

app/src/main/java/app/grapheneos/pdfviewer/fragment/JumpToPageFragment.kt

@@ -1,58 +0,0 @@
-package app.grapheneos.pdfviewer.fragment
-
-import android.app.Dialog
-import android.content.DialogInterface
-import android.os.Bundle
-import android.view.Gravity
-import android.widget.FrameLayout
-import android.widget.NumberPicker
-import androidx.fragment.app.DialogFragment
-import app.grapheneos.pdfviewer.PdfViewer
-import com.google.android.material.dialog.MaterialAlertDialogBuilder
-
-class JumpToPageFragment(private val pdfViewer: PdfViewer) : DialogFragment() {
-
-    companion object {
-        const val TAG = "JumpToPageFragment"
-        private const val STATE_PICKER_CUR = "picker_cur"
-        private const val STATE_PICKER_MIN = "picker_min"
-        private const val STATE_PICKER_MAX = "picker_max"
-    }
-
-    private val mPicker: NumberPicker by lazy { NumberPicker(requireActivity()) }
-
-    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
-
-        if (savedInstanceState != null) {
-            mPicker.minValue = savedInstanceState.getInt(STATE_PICKER_MIN)
-            mPicker.maxValue = savedInstanceState.getInt(STATE_PICKER_MAX)
-            mPicker.value = savedInstanceState.getInt(STATE_PICKER_CUR)
-        } else {
-            mPicker.minValue = 1
-            mPicker.maxValue = pdfViewer.mNumPages
-            mPicker.value = pdfViewer.mPage
-        }
-        val layout = FrameLayout(requireActivity())
-        layout.addView(
-            mPicker, FrameLayout.LayoutParams(
-                FrameLayout.LayoutParams.WRAP_CONTENT,
-                FrameLayout.LayoutParams.WRAP_CONTENT,
-                Gravity.CENTER
-            )
-        )
-        return MaterialAlertDialogBuilder(requireActivity())
-            .setView(layout)
-            .setPositiveButton(android.R.string.ok) { _: DialogInterface?, _: Int ->
-                mPicker.clearFocus()
-                pdfViewer.onJumpToPageInDocument(mPicker.value)
-            }
-            .setNegativeButton(android.R.string.cancel, null)
-            .create()
-    }
-
-    override fun onSaveInstanceState(outState: Bundle) {
-        outState.putInt(STATE_PICKER_MIN, mPicker.minValue)
-        outState.putInt(STATE_PICKER_MAX, mPicker.maxValue)
-        outState.putInt(STATE_PICKER_CUR, mPicker.value)
-    }
-}

app/src/main/java/app/grapheneos/pdfviewer/loader/DocumentPropertiesAsyncTaskLoader.java

@@ -1,51 +0,0 @@
-package app.grapheneos.pdfviewer.loader;
-
-import android.content.Context;
-
-import androidx.annotation.Nullable;
-import androidx.loader.content.AsyncTaskLoader;
-
-import java.util.List;
-
-public class DocumentPropertiesAsyncTaskLoader extends AsyncTaskLoader<List<CharSequence>> {
-
-    public static final String TAG = "DocumentPropertiesLoader";
-
-    public static final int ID = 1;
-
-    private final String mProperties;
-    private final int mNumPages;
-
-    String fileName;
-    Long fileSize;
-
-    public DocumentPropertiesAsyncTaskLoader(Context context, String properties, int numPages, String fileName, Long fileSize) {
-        super(context);
-
-        mProperties = properties;
-        mNumPages = numPages;
-        this.fileName = fileName;
-        this.fileSize = fileSize;
-    }
-
-
-    @Override
-    protected void onStartLoading() {
-        forceLoad();
-    }
-
-    @Nullable
-    @Override
-    public List<CharSequence> loadInBackground() {
-
-        DocumentPropertiesLoader loader = new DocumentPropertiesLoader(
-                getContext(),
-                mProperties,
-                mNumPages,
-                fileName,
-                fileSize
-        );
-
-        return loader.loadAsList();
-    }
-}

app/src/main/java/app/grapheneos/pdfviewer/loader/DocumentPropertiesLoader.java

@@ -0,0 +1,115 @@
+package app.grapheneos.pdfviewer.loader;
+
+import android.content.Context;
+import android.graphics.Typeface;
+import android.text.SpannableStringBuilder;
+import android.text.Spanned;
+import android.text.style.StyleSpan;
+import android.util.Log;
+
+import androidx.loader.content.AsyncTaskLoader;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.text.ParseException;
+import java.util.ArrayList;
+import java.util.List;
+
+import app.grapheneos.pdfviewer.R;
+import app.grapheneos.pdfviewer.Utils;
+
+public class DocumentPropertiesLoader extends AsyncTaskLoader<List<CharSequence>> {
+    public static final String TAG = "DocumentPropertiesLoader";
+
+    public static final int ID = 1;
+
+    private final String mProperties;
+    private final int mNumPages;
+
+    String fileName;
+    Long fileSize;
+
+    public DocumentPropertiesLoader(Context context, String properties, int numPages, String fileName, Long fileSize) {
+        super(context);
+
+        mProperties = properties;
+        mNumPages = numPages;
+        this.fileName = fileName;
+        this.fileSize = fileSize;
+    }
+
+    @Override
+    public List<CharSequence> loadInBackground() {
+        final Context context = getContext();
+
+        final String[] names = context.getResources().getStringArray(R.array.property_names);
+        final List<CharSequence> properties = new ArrayList<>(names.length);
+
+        properties.add(getProperty(null, names[0], fileName));
+        properties.add(getProperty(null, names[1], Utils.parseFileSize(fileSize)));
+
+        try {
+            final JSONObject json = new JSONObject(mProperties);
+
+            properties.add(getProperty(json, names[2], "Title"));
+            properties.add(getProperty(json, names[3], "Author"));
+            properties.add(getProperty(json, names[4], "Subject"));
+            properties.add(getProperty(json, names[5], "Keywords"));
+            properties.add(getProperty(json, names[6], "CreationDate"));
+            properties.add(getProperty(json, names[7], "ModDate"));
+            properties.add(getProperty(json, names[8], "Producer"));
+            properties.add(getProperty(json, names[9], "Creator"));
+            properties.add(getProperty(json, names[10], "PDFFormatVersion"));
+            properties.add(getProperty(null, names[11], String.valueOf(mNumPages)));
+
+            return properties;
+        } catch (JSONException e) {
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+    @Override
+    public void deliverResult(List<CharSequence> properties) {
+        if (!isReset() && isStarted()) {
+            super.deliverResult(properties);
+        }
+    }
+
+    @Override
+    protected void onStartLoading() {
+        forceLoad();
+    }
+
+    @Override
+    protected void onStopLoading() {
+        cancelLoad();
+    }
+
+    @Override
+    protected void onReset() {
+        super.onReset();
+
+        onStopLoading();
+    }
+
+    private CharSequence getProperty(final JSONObject json, String name, String specName) {
+        final SpannableStringBuilder property = new SpannableStringBuilder(name).append(":\n");
+        final String value = json != null ? json.optString(specName, "-") : specName;
+
+        if (specName != null && specName.endsWith("Date")) {
+            final Context context = getContext();
+            try {
+                property.append(value.equals("-") ? value : Utils.parseDate(value));
+            } catch (ParseException e) {
+                Log.w(TAG, e.getMessage() + " for " + value + " at offset: " + e.getErrorOffset());
+                property.append(context.getString(R.string.document_properties_invalid_date));
+            }
+        } else {
+            property.append(value);
+        }
+        property.setSpan(new StyleSpan(Typeface.BOLD), 0, name.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
+        return property;
+    }
+}

app/src/main/java/app/grapheneos/pdfviewer/loader/DocumentPropertiesLoader.kt

@@ -1,88 +0,0 @@
-package app.grapheneos.pdfviewer.loader
-
-import android.content.Context
-import android.graphics.Typeface
-import android.text.SpannableStringBuilder
-import android.text.Spanned
-import android.text.format.Formatter
-import android.text.style.StyleSpan
-import android.util.Log
-import app.grapheneos.pdfviewer.R
-import org.json.JSONException
-
-class DocumentPropertiesLoader(
-    private val context: Context,
-    private val properties: String,
-    private val numPages: Int,
-    private val fileName: String,
-    private val fileSize: Long,
-) {
-
-    fun loadAsList(): List<CharSequence> {
-        return load().map { item ->
-            val name = context.getString(item.key.nameResource)
-            val value = item.value
-
-            SpannableStringBuilder()
-                .append(name)
-                .append(":\n")
-                .append(value)
-                .apply {
-                    setSpan(
-                        StyleSpan(Typeface.BOLD),
-                        0,
-                        name.length,
-                        Spanned.SPAN_EXCLUSIVE_EXCLUSIVE
-                    )
-                }
-        }
-    }
-
-    private fun load(): Map<DocumentProperty, String> {
-        val result = mutableMapOf<DocumentProperty, String>()
-        result.addFileProperties()
-        result.addPageSizeProperty()
-        result.addPDFJsProperties()
-        return result
-    }
-
-    private fun MutableMap<DocumentProperty, String>.addPageSizeProperty() {
-        this[DocumentProperty.Pages] = java.lang.String.valueOf(numPages)
-    }
-
-    private fun MutableMap<DocumentProperty, String>.addFileProperties() {
-        putAll(getFileProperties())
-    }
-
-    private fun MutableMap<DocumentProperty, String>.addPDFJsProperties() {
-        putAll(getPDFJsProperties())
-    }
-
-    private fun getPDFJsProperties(): Map<DocumentProperty, String> {
-        return try {
-            PDFJsPropertiesToDocumentPropertyConverter(
-                properties,
-                context.getString(R.string.document_properties_invalid_date),
-                parseExceptionListener = { parseException, value ->
-                    Log.w(
-                        DocumentPropertiesAsyncTaskLoader.TAG,
-                        "${parseException.message} for $value at offset: ${parseException.errorOffset}"
-                    )
-                }
-            ).convert()
-        } catch (e: JSONException) {
-            Log.w(
-                DocumentPropertiesAsyncTaskLoader.TAG,
-                "invalid properties"
-            )
-            emptyMap()
-        }
-    }
-
-    private fun getFileProperties(): Map<DocumentProperty, String> {
-        val collections = mutableMapOf<DocumentProperty, String>()
-        collections[DocumentProperty.FileName] = fileName
-        collections[DocumentProperty.FileSize] = Formatter.formatFileSize(context, fileSize)
-        return collections
-    }
-}

app/src/main/java/app/grapheneos/pdfviewer/loader/DocumentProperty.kt

@@ -1,35 +0,0 @@
-package app.grapheneos.pdfviewer.loader
-
-import androidx.annotation.StringRes
-import app.grapheneos.pdfviewer.R
-
-private const val TITLE_KEY = "Title"
-private const val AUTHOR_KEY = "Author"
-private const val SUBJECT_KEY = "Subject"
-private const val KEYWORDS_KEY = "Keywords"
-private const val CREATION_DATE_KEY = "CreationDate"
-private const val MODIFY_DATE_KEY = "ModDate"
-private const val PRODUCER_KEY = "Producer"
-private const val CREATOR_KEY = "Creator"
-private const val PDF_VERSION_KEY = "PDFFormatVersion"
-
-const val DEFAULT_VALUE = "-"
-
-enum class DocumentProperty(
-    val key: String = "",
-    @StringRes val nameResource: Int,
-    val isDate: Boolean = false
-) {
-    FileName(key = "", nameResource = R.string.file_name),
-    FileSize(key = "", nameResource = R.string.file_size),
-    Pages(key = "", nameResource = R.string.pages),
-    Title(key = TITLE_KEY, nameResource = R.string.title),
-    Author(key = AUTHOR_KEY, nameResource = R.string.author),
-    Subject(key = SUBJECT_KEY, nameResource = R.string.subject),
-    Keywords(key = KEYWORDS_KEY, nameResource = R.string.keywords),
-    CreationDate(key = CREATION_DATE_KEY, nameResource = R.string.creation_date, isDate = true),
-    ModifyDate(key = MODIFY_DATE_KEY, nameResource = R.string.modify_date, isDate = true),
-    Producer(key = PRODUCER_KEY, nameResource = R.string.producer),
-    Creator(key = CREATOR_KEY, nameResource = R.string.creator),
-    PDFVersion(key = PDF_VERSION_KEY, nameResource = R.string.pdf_version);
-}

app/src/main/java/app/grapheneos/pdfviewer/loader/PDFJsPropertiesToDocumentPropertyConverter.kt

@@ -1,47 +0,0 @@
-package app.grapheneos.pdfviewer.loader
-
-import app.grapheneos.pdfviewer.Utils
-import org.json.JSONException
-import org.json.JSONObject
-import java.text.ParseException
-import kotlin.jvm.Throws
-
-class PDFJsPropertiesToDocumentPropertyConverter(
-    private val properties: String,
-    private val propertyInvalidDate: String,
-    private val parseExceptionListener: (e: ParseException, value: String) -> Unit
-) {
-
-    @Throws(JSONException::class)
-    fun convert(): Map<DocumentProperty, String> {
-        val result = mutableMapOf<DocumentProperty, String>()
-
-        val json = JSONObject(properties)
-        addJsonProperties(json, result)
-        return result
-    }
-
-    private fun addJsonProperties(
-        json: JSONObject,
-        collections: MutableMap<DocumentProperty, String>
-    ) {
-        for (documentProperty in DocumentProperty.values()) {
-            val key = documentProperty.key
-            if (key.isEmpty()) continue
-            val value = json.optString(key, DEFAULT_VALUE)
-            collections[documentProperty] = prettify(documentProperty, value)
-        }
-    }
-
-    private fun prettify(property: DocumentProperty, value: String): String {
-        if (value != DEFAULT_VALUE && property.isDate) {
-            return try {
-                Utils.parseDate(value)
-            } catch (parseException: ParseException) {
-                parseExceptionListener.invoke(parseException, value)
-                propertyInvalidDate
-            }
-        }
-        return value
-    }
-}

app/src/main/res/menu/pdf_viewer.xml

@@ -11,13 +11,13 @@
         android:id="@+id/action_previous"
         android:icon="@drawable/ic_navigate_before_24dp"
         android:title="@string/action_previous"
-        app:showAsAction="always" />
+        app:showAsAction="ifRoom" />
 
     <item
         android:id="@+id/action_next"
         android:icon="@drawable/ic_navigate_next_24dp"
         android:title="@string/action_next"
-        app:showAsAction="always" />
+        app:showAsAction="ifRoom" />
 
     <item
         android:id="@+id/action_first"

app/src/main/res/menu/pdf_viewer_debug.xml

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<menu xmlns:app="http://schemas.android.com/apk/res-auto"
-    xmlns:android="http://schemas.android.com/apk/res/android">
-
-    <item
-        android:id="@+id/debug_action_toggle_text_layer_visibility"
-        android:title="@string/debug_action_toggle_text_layer_visibility"
-        app:showAsAction="never" />
-
-</menu>

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

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string-array name="property_names">
+        <item>File name</item>
+        <item>File size</item>
+        <item>Title</item>
+        <item>Author</item>
+        <item>Subject</item>
+        <item>Keywords</item>
+        <item>Creation date</item>
+        <item>Modify date</item>
+        <item>Producer</item>
+        <item>Creator</item>
+        <item>PDF version</item>
+        <item>Pages</item>
+    </string-array>
+</resources>

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

@@ -11,8 +11,6 @@
     <string name="action_rotate_counterclockwise">Rotate counterclockwise</string>
     <string name="action_view_document_properties">Properties</string>
 
-    <string name="debug_action_toggle_text_layer_visibility">Toggle text layer visibility</string>
-
     <string name="document_properties_invalid_date">Invalid date</string>
     <string name="document_properties_retrieval_failed">Failed to obtain document metadata</string>
 
@@ -23,17 +21,4 @@
     <string name="password_prompt_description">Enter the password to decrypt this PDF file</string>
     <string name="open">Open</string>
     <string name="cancel">Cancel</string>
-
-    <string name="file_name">File name</string>
-    <string name="file_size">File size</string>
-    <string name="title">Title</string>
-    <string name="author">Author</string>
-    <string name="subject">Subject</string>
-    <string name="keywords">Keywords</string>
-    <string name="creation_date">Creation date</string>
-    <string name="modify_date">Modify date</string>
-    <string name="producer">Producer</string>
-    <string name="creator">Creator</string>
-    <string name="pdf_version">PDF version</string>
-    <string name="pages">Pages</string>
 </resources>

build.gradle.kts

@@ -1,6 +1,18 @@
-plugins {
-    id("com.android.application") apply false
-    id("org.jetbrains.kotlin.android") apply false
+buildscript {
+    repositories {
+        // dependabot cannot handle google()
+        maven {
+            url = uri("https://dl.google.com/dl/android/maven2")
+        }
+        // dependabot cannot handle mavenCentral()
+        maven {
+            url = uri("https://repo.maven.apache.org/maven2")
+        }
+    }
+    dependencies {
+        classpath("com.android.tools.build:gradle:7.3.1")
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.7.22")
+    }
 }
 
 allprojects {

gradle.properties

@@ -1,3 +1,4 @@
 org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
 android.useAndroidX=true
+android.enableR8.fullMode=true
 kotlin.code.style=official

gradle/wrapper/gradle-wrapper.properties

@@ -1,8 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionSha256Sum=38f66cd6eef217b4c35855bb11ea4e9fbc53594ccccb5fb82dfd317ef8c2c5a3
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.2-bin.zip
-networkTimeout=10000
-validateDistributionUrl=true
+distributionSha256Sum=f6b8596b10cce501591e92f229816aa4046424f3b24d771751b06779d58c8ec4
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

gradlew

@@ -55,7 +55,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -80,11 +80,14 @@ do
     esac
 done
 
-# This is normally unused
-# shellcheck disable=SC2034
-APP_BASE_NAME=${0##*/}
 APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
 
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
 
@@ -130,29 +133,22 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    if ! command -v java >/dev/null 2>&1
-    then
-        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
-    fi
 fi
 
 # Increase the maximum file descriptors if we can.
 if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
-        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
     case $MAX_FD in  #(
       '' | soft) :;; #(
       *)
-        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -197,10 +193,6 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
-
 # Collect all arguments for the java command;
 #   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
 #     shell script including quotes and variable substitutions, so put them in

gradlew.bat

@@ -26,7 +26,6 @@ if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
 if "%DIRNAME%"=="" set DIRNAME=.
-@rem This is normally unused
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 

settings.gradle.kts

@@ -1,9 +1,3 @@
-pluginManagement {
-    repositories {
-        google()
-        mavenCentral()
-    }
-}
 dependencyResolutionManagement {
     repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
     repositories {