1 files changed, 266 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/RuntimeSettings.java b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/RuntimeSettings.java
new file mode 100644
index 0000000000..299dec95f1
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/RuntimeSettings.java
@@ -0,0 +1,266 @@
+/* -*- 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.os.Parcel;
+import android.os.Parcelable;
+import androidx.annotation.AnyThread;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.collection.ArrayMap;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Map;
+import org.mozilla.gecko.EventDispatcher;
+import org.mozilla.gecko.util.GeckoBundle;
+
+/**
+ * Base class for (nested) runtime settings.
+ *
+ * <p>Handles pref-based settings. Please extend this class when adding nested settings for
+ * GeckoRuntimeSettings.
+ */
+public abstract class RuntimeSettings implements Parcelable {
+  /**
+   * Base class for (nested) runtime settings builders.
+   *
+   * <p>Please extend this class when adding nested settings builders for GeckoRuntimeSettings.
+   */
+  public abstract static class Builder<Settings extends RuntimeSettings> {
+    private final Settings mSettings;
+
+    @SuppressWarnings("checkstyle:javadocmethod")
+    public Builder() {
+      mSettings = newSettings(null);
+    }
+
+    /**
+     * Finalize and return the settings.
+     *
+     * @return The constructed settings.
+     */
+    @AnyThread
+    public @NonNull Settings build() {
+      return newSettings(mSettings);
+    }
+
+    @AnyThread
+    protected @NonNull Settings getSettings() {
+      return mSettings;
+    }
+
+    /**
+     * Create a default or copy settings object.
+     *
+     * @param settings Settings object to copy, null for default settings.
+     * @return The constructed settings object.
+     */
+    @AnyThread
+    protected abstract @NonNull Settings newSettings(final @Nullable Settings settings);
+  }
+
+  /** Used to handle pref-based settings. */
+  /* package */ class Pref<T> {
+    public final String name;
+    public final T defaultValue;
+    private T mValue;
+    private boolean mIsSet;
+
+    public Pref(@NonNull final String name, final T defaultValue) {
+      this.name = name;
+      this.defaultValue = defaultValue;
+      mValue = defaultValue;
+
+      RuntimeSettings.this.addPref(this);
+    }
+
+    public void set(final T newValue) {
+      mValue = newValue;
+      mIsSet = true;
+    }
+
+    public void commit(final T newValue) {
+      if (newValue.equals(mValue)) {
+        return;
+      }
+      set(newValue);
+      commit();
+    }
+
+    public void commit() {
+      final GeckoRuntime runtime = RuntimeSettings.this.getRuntime();
+      if (runtime == null) {
+        return;
+      }
+      final GeckoBundle prefs = new GeckoBundle(1);
+      addToBundle(prefs);
+      runtime.setDefaultPrefs(prefs);
+    }
+
+    public T get() {
+      return mValue;
+    }
+
+    public boolean isSet() {
+      return mIsSet;
+    }
+
+    public void reset() {
+      mValue = defaultValue;
+      mIsSet = false;
+    }
+
+    private void addToBundle(final GeckoBundle bundle) {
+      final T value = mIsSet ? mValue : defaultValue;
+      if (value instanceof String) {
+        bundle.putString(name, (String) value);
+      } else if (value instanceof Integer) {
+        bundle.putInt(name, (Integer) value);
+      } else if (value instanceof Boolean) {
+        bundle.putBoolean(name, (Boolean) value);
+      } else {
+        throw new UnsupportedOperationException("Unhandled pref type for " + name);
+      }
+    }
+  }
+
+  private RuntimeSettings mParent;
+  private final ArrayList<RuntimeSettings> mChildren;
+  private final ArrayList<Pref<?>> mPrefs;
+
+  protected RuntimeSettings() {
+    this(null /* parent */);
+  }
+
+  /**
+   * Create settings object.
+   *
+   * @param parent The parent settings, specify in case of nested settings.
+   */
+  protected RuntimeSettings(final @Nullable RuntimeSettings parent) {
+    mPrefs = new ArrayList<Pref<?>>();
+    mChildren = new ArrayList<RuntimeSettings>();
+
+    setParent(parent);
+  }
+
+  /**
+   * Update the prefs based on the provided settings.
+   *
+   * @param settings Copy from this settings.
+   */
+  @AnyThread
+  protected void updatePrefs(final @NonNull RuntimeSettings settings) {
+    if (mPrefs.size() != settings.mPrefs.size()) {
+      throw new IllegalArgumentException("Settings must be compatible");
+    }
+
+    for (int i = 0; i < mPrefs.size(); ++i) {
+      if (!mPrefs.get(i).name.equals(settings.mPrefs.get(i).name)) {
+        throw new IllegalArgumentException("Settings must be compatible");
+      }
+      if (!settings.mPrefs.get(i).isSet()) {
+        continue;
+      }
+      // We know it is safe.
+      @SuppressWarnings("unchecked")
+      final Pref<Object> uncheckedPref = (Pref<Object>) mPrefs.get(i);
+      uncheckedPref.commit(settings.mPrefs.get(i).get());
+    }
+  }
+
+  /* package */ @Nullable
+  GeckoRuntime getRuntime() {
+    if (mParent != null) {
+      return mParent.getRuntime();
+    }
+    return null;
+  }
+
+  private void setParent(final @Nullable RuntimeSettings parent) {
+    mParent = parent;
+    if (mParent != null) {
+      mParent.addChild(this);
+    }
+  }
+
+  private void addChild(final @NonNull RuntimeSettings child) {
+    mChildren.add(child);
+  }
+
+  /* pacakge */ void addPref(final Pref<?> pref) {
+    mPrefs.add(pref);
+  }
+
+  /**
+   * Return a mapping of the prefs managed in this settings, including child settings.
+   *
+   * @return A key-value mapping of the prefs.
+   */
+  /* package */ @NonNull
+  Map<String, Object> getPrefsMap() {
+    final ArrayMap<String, Object> prefs = new ArrayMap<>();
+    forAllPrefs(pref -> prefs.put(pref.name, pref.get()));
+
+    return Collections.unmodifiableMap(prefs);
+  }
+
+  /**
+   * Iterates through all prefs in this RuntimeSettings instance and in all children, grandchildren,
+   * etc.
+   */
+  private void forAllPrefs(final GeckoResult.Consumer<Pref<?>> visitor) {
+    for (final RuntimeSettings child : mChildren) {
+      child.forAllPrefs(visitor);
+    }
+
+    for (final Pref<?> pref : mPrefs) {
+      visitor.accept(pref);
+    }
+  }
+
+  /**
+   * Reset the prefs managed by this settings and its children.
+   *
+   * <p>The actual prefs values are set via {@link #getPrefsMap} during initialization and via
+   * {@link Pref#commit} during runtime for individual prefs.
+   */
+  /* package */ void commitResetPrefs() {
+    final ArrayList<String> names = new ArrayList<String>();
+    forAllPrefs(pref -> names.add(pref.name));
+
+    final GeckoBundle data = new GeckoBundle(1);
+    data.putStringArray("names", names);
+    EventDispatcher.getInstance().dispatch("GeckoView:ResetUserPrefs", data);
+  }
+
+  @Override // Parcelable
+  @AnyThread
+  public int describeContents() {
+    return 0;
+  }
+
+  @Override // Parcelable
+  @AnyThread
+  public void writeToParcel(final Parcel out, final int flags) {
+    for (final Pref<?> pref : mPrefs) {
+      out.writeValue(pref.get());
+    }
+  }
+
+  @AnyThread
+  // AIDL code may call readFromParcel even though it's not part of Parcelable.
+  @SuppressWarnings("checkstyle:javadocmethod")
+  public void readFromParcel(final @NonNull Parcel source) {
+    for (final Pref<?> pref : mPrefs) {
+      // We know this is safe.
+      @SuppressWarnings("unchecked")
+      final Pref<Object> uncheckedPref = (Pref<Object>) pref;
+      uncheckedPref.commit(source.readValue(getClass().getClassLoader()));
+    }
+  }
+}