/* -*- 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.IntDef;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Arrays;
import java.util.Collection;
import org.mozilla.gecko.util.GeckoBundle;

@AnyThread
public final class GeckoSessionSettings implements Parcelable {

  /** Settings builder used to construct the settings object. */
  @AnyThread
  public static final class Builder {
    private final GeckoSessionSettings mSettings;

    @SuppressWarnings("checkstyle:javadocmethod")
    public Builder() {
      mSettings = new GeckoSessionSettings();
    }

    @SuppressWarnings("checkstyle:javadocmethod")
    public Builder(final GeckoSessionSettings settings) {
      mSettings = new GeckoSessionSettings(settings);
    }

    /**
     * Finalize and return the settings.
     *
     * @return The constructed settings.
     */
    public @NonNull GeckoSessionSettings build() {
      return new GeckoSessionSettings(mSettings);
    }

    /**
     * Set the chrome URI.
     *
     * @param uri The URI to set the Chrome URI to.
     * @return This Builder instance.
     */
    public @NonNull Builder chromeUri(final @NonNull String uri) {
      mSettings.setChromeUri(uri);
      return this;
    }

    /**
     * Set the screen id.
     *
     * @param id The screen id.
     * @return This Builder instance.
     */
    public @NonNull Builder screenId(final int id) {
      mSettings.setScreenId(id);
      return this;
    }

    /**
     * Set the privacy mode for this instance.
     *
     * @param flag A flag determining whether Private Mode should be enabled. Default is false.
     * @return This Builder instance.
     */
    public @NonNull Builder usePrivateMode(final boolean flag) {
      mSettings.setUsePrivateMode(flag);
      return this;
    }

    /**
     * Set the session context ID for this instance. Setting a context ID partitions the cookie jars
     * based on the provided IDs. This isolates the browser storage like cookies and localStorage
     * between sessions, only sessions that share the same ID share storage data.
     *
     * <p>Warning: Storage data is collected persistently for each context, to delete context data,
     * call {@link StorageController#clearDataForSessionContext} for the given context.
     *
     * @param value The custom context ID. The default ID is null, which removes isolation for this
     *     instance.
     * @return This Builder instance.
     */
    public @NonNull Builder contextId(final @Nullable String value) {
      mSettings.setContextId(value);
      return this;
    }

    /**
     * Set whether tracking protection should be enabled.
     *
     * @param flag A flag determining whether tracking protection should be enabled. Default is
     *     false.
     * @return This Builder instance.
     */
    public @NonNull Builder useTrackingProtection(final boolean flag) {
      mSettings.setUseTrackingProtection(flag);
      return this;
    }

    /**
     * Set the user agent mode.
     *
     * @param mode The mode to set the user agent to. Use one or more of the {@link
     *     GeckoSessionSettings#USER_AGENT_MODE_MOBILE GeckoSessionSettings.USER_AGENT_MODE_*}
     *     flags.
     * @return This Builder instance.
     */
    public @NonNull Builder userAgentMode(@UserAgentMode final int mode) {
      mSettings.setUserAgentMode(mode);
      return this;
    }

    /**
     * Override the user agent.
     *
     * @param agent The user agent to use.
     * @return This Builder instance.
     */
    public @NonNull Builder userAgentOverride(final @NonNull String agent) {
      mSettings.setUserAgentOverride(agent);
      return this;
    }

    /**
     * Specify which display-mode to use.
     *
     * @param mode The mode to set the display to. Use one or more of the {@link
     *     GeckoSessionSettings#DISPLAY_MODE_BROWSER GeckoSessionSettings.DISPLAY_MODE_*} flags.
     * @return This Builder instance.
     */
    public @NonNull Builder displayMode(@DisplayMode final int mode) {
      mSettings.setDisplayMode(mode);
      return this;
    }

    /**
     * Set whether to suspend the playing of media when the session is inactive.
     *
     * @param flag A flag determining whether media should be suspended. Default is false.
     * @return This Builder instance.
     */
    public @NonNull Builder suspendMediaWhenInactive(final boolean flag) {
      mSettings.setSuspendMediaWhenInactive(flag);
      return this;
    }

    /**
     * Set whether JavaScript support should be enabled.
     *
     * @param flag A flag determining whether JavaScript should be enabled. Default is true.
     * @return This Builder instance.
     */
    public @NonNull Builder allowJavascript(final boolean flag) {
      mSettings.setAllowJavascript(flag);
      return this;
    }

    /**
     * Set whether the entire accessible tree should be exposed with no caching.
     *
     * @param flag A flag determining if the entire accessible tree should be exposed. Default is
     *     false.
     * @return This Builder instance.
     */
    public @NonNull Builder fullAccessibilityTree(final boolean flag) {
      mSettings.setFullAccessibilityTree(flag);
      return this;
    }

    /**
     * Specify which viewport mode to use.
     *
     * @param mode The mode to set the viewport to. Use one or more of the {@link
     *     GeckoSessionSettings#VIEWPORT_MODE_MOBILE GeckoSessionSettings.VIEWPORT_MODE_*} flags.
     * @return This Builder instance.
     */
    public @NonNull Builder viewportMode(@ViewportMode final int mode) {
      mSettings.setViewportMode(mode);
      return this;
    }
  }

  private static final String LOGTAG = "GeckoSessionSettings";
  private static final boolean DEBUG = false;

  /** This value is for the display member of Web App Manifests */
  @Retention(RetentionPolicy.SOURCE)
  @IntDef({
    DISPLAY_MODE_BROWSER,
    DISPLAY_MODE_MINIMAL_UI,
    DISPLAY_MODE_STANDALONE,
    DISPLAY_MODE_FULLSCREEN
  })
  public @interface DisplayMode {}

  // This needs to match GeckoViewSettings.jsm
  /** "browser" value of the display member in Web App Manifests */
  public static final int DISPLAY_MODE_BROWSER = 0;

  /** "minimal-ui" value of the display member in Web App Manifests */
  public static final int DISPLAY_MODE_MINIMAL_UI = 1;

  /** "standalone" value of the display member in Web App Manifests */
  public static final int DISPLAY_MODE_STANDALONE = 2;

  /** "fullscreen" value of the display member in Web App Manifests */
  public static final int DISPLAY_MODE_FULLSCREEN = 3;

  /** The user agent string mode */
  @Retention(RetentionPolicy.SOURCE)
  @IntDef({
    USER_AGENT_MODE_MOBILE,
    USER_AGENT_MODE_DESKTOP,
    USER_AGENT_MODE_VR,
  })
  public @interface UserAgentMode {}

  // This needs to match GeckoViewSettingsChild.js and GeckoViewSettings.jsm
  /** The user agent mode is mobile device */
  public static final int USER_AGENT_MODE_MOBILE = 0;

  /** The user agent mobe is desktop device */
  public static final int USER_AGENT_MODE_DESKTOP = 1;

  /** The user agent mode is VR device */
  public static final int USER_AGENT_MODE_VR = 2;

  /** The view port mode */
  @Retention(RetentionPolicy.SOURCE)
  @IntDef({VIEWPORT_MODE_MOBILE, VIEWPORT_MODE_DESKTOP})
  public @interface ViewportMode {}

  // This needs to match GeckoViewSettingsChild.js
  /**
   * Mobile-friendly pages will be rendered using a viewport based on their &lt;meta&gt; viewport
   * tag. All other pages will be rendered using a special desktop mode viewport, which has a width
   * of 980 CSS px.
   */
  public static final int VIEWPORT_MODE_MOBILE = 0;

  /**
   * All pages will be rendered using the special desktop mode viewport, which has a width of 980
   * CSS px, regardless of whether the page has a &lt;meta&gt; viewport tag specified or not.
   */
  public static final int VIEWPORT_MODE_DESKTOP = 1;

  public static class Key<T> {
    /* package */ final String name;
    /* package */ final boolean initOnly;
    /* package */ final Collection<T> values;

    /* package */ Key(final String name) {
      this(name, /* initOnly */ false, /* values */ null);
    }

    /* package */ Key(final String name, final boolean initOnly, final Collection<T> values) {
      this.name = name;
      this.initOnly = initOnly;
      this.values = values;
    }
  }

  /**
   * Key to set the chrome window URI, or null to use default URI. Read-only once session is open.
   */
  private static final Key<String> CHROME_URI =
      new Key<String>("chromeUri", /* initOnly */ true, /* values */ null);

  /** Key to set the window screen ID, or 0 to use default ID. Read-only once session is open. */
  private static final Key<Integer> SCREEN_ID =
      new Key<Integer>("screenId", /* initOnly */ true, /* values */ null);

  /** Key to enable and disable tracking protection. */
  private static final Key<Boolean> USE_TRACKING_PROTECTION =
      new Key<Boolean>("useTrackingProtection");

  /** Key to enable and disable private mode browsing. Read-only once session is open. */
  private static final Key<Boolean> USE_PRIVATE_MODE =
      new Key<Boolean>("usePrivateMode", /* initOnly */ true, /* values */ null);

  /** Key to specify which user agent mode we should use. */
  private static final Key<Integer> USER_AGENT_MODE =
      new Key<Integer>(
          "userAgentMode", /* initOnly */
          false,
          Arrays.asList(USER_AGENT_MODE_MOBILE, USER_AGENT_MODE_DESKTOP, USER_AGENT_MODE_VR));

  /**
   * Key to specify the user agent override string. Set value to null to use the user agent
   * specified by USER_AGENT_MODE.
   */
  private static final Key<String> USER_AGENT_OVERRIDE =
      new Key<String>("userAgentOverride", /* initOnly */ false, /* values */ null);

  /** Key to specify which viewport mode we should use. */
  private static final Key<Integer> VIEWPORT_MODE =
      new Key<Integer>(
          "viewportMode", /* initOnly */
          false,
          Arrays.asList(VIEWPORT_MODE_MOBILE, VIEWPORT_MODE_DESKTOP));

  /** Key to specify which display-mode we should use. */
  private static final Key<Integer> DISPLAY_MODE =
      new Key<Integer>(
          "displayMode", /* initOnly */
          false,
          Arrays.asList(
              DISPLAY_MODE_BROWSER, DISPLAY_MODE_MINIMAL_UI,
              DISPLAY_MODE_STANDALONE, DISPLAY_MODE_FULLSCREEN));

  /** Key to specify if media should be suspended when the session is inactive. */
  private static final Key<Boolean> SUSPEND_MEDIA_WHEN_INACTIVE =
      new Key<Boolean>("suspendMediaWhenInactive", /* initOnly */ false, /* values */ null);

  /** Key to specify if JavaScript should be allowed on this session. */
  private static final Key<Boolean> ALLOW_JAVASCRIPT =
      new Key<Boolean>("allowJavascript", /* initOnly */ false, /* values */ null);

  /** Key to specify if entire accessible tree should be exposed with no caching. */
  private static final Key<Boolean> FULL_ACCESSIBILITY_TREE =
      new Key<Boolean>("fullAccessibilityTree", /* initOnly */ false, /* values */ null);

  /**
   * Key to specify if this GeckoSession is a Popup or not. Popup sessions can paint over other
   * sessions and are not exposed to the tabs WebExtension API.
   */
  private static final Key<Boolean> IS_POPUP =
      new Key<Boolean>("isPopup", /* initOnly */ false, /* values */ null);

  /** Internal Gecko key to specify the session context ID. Derived from `UNSAFE_CONTEXT_ID`. */
  private static final Key<String> CONTEXT_ID =
      new Key<String>("sessionContextId", /* initOnly */ true, /* values */ null);

  /** User-provided key to specify the session context ID. */
  private static final Key<String> UNSAFE_CONTEXT_ID =
      new Key<String>("unsafeSessionContextId", /* initOnly */ true, /* values */ null);

  private final GeckoSession mSession;
  private final GeckoBundle mBundle;

  @SuppressWarnings("checkstyle:javadocmethod")
  public GeckoSessionSettings() {
    this(null, null);
  }

  @SuppressWarnings("checkstyle:javadocmethod")
  public GeckoSessionSettings(final @NonNull GeckoSessionSettings settings) {
    this(settings, null);
  }

  /* package */ GeckoSessionSettings(
      final @Nullable GeckoSessionSettings settings, final @Nullable GeckoSession session) {
    mSession = session;

    if (settings != null) {
      mBundle = new GeckoBundle(settings.mBundle);
      return;
    }

    mBundle = new GeckoBundle();
    mBundle.putString(CHROME_URI.name, null);
    mBundle.putInt(SCREEN_ID.name, 0);
    mBundle.putBoolean(USE_TRACKING_PROTECTION.name, false);
    mBundle.putBoolean(USE_PRIVATE_MODE.name, false);
    mBundle.putBoolean(SUSPEND_MEDIA_WHEN_INACTIVE.name, false);
    mBundle.putBoolean(ALLOW_JAVASCRIPT.name, true);
    mBundle.putBoolean(FULL_ACCESSIBILITY_TREE.name, false);
    mBundle.putBoolean(IS_POPUP.name, false);
    mBundle.putInt(USER_AGENT_MODE.name, USER_AGENT_MODE_MOBILE);
    mBundle.putString(USER_AGENT_OVERRIDE.name, null);
    mBundle.putInt(VIEWPORT_MODE.name, VIEWPORT_MODE_MOBILE);
    mBundle.putInt(DISPLAY_MODE.name, DISPLAY_MODE_BROWSER);
    mBundle.putString(CONTEXT_ID.name, null);
    mBundle.putString(UNSAFE_CONTEXT_ID.name, null);
  }

  /**
   * Set whether tracking protection should be enabled.
   *
   * @param value A flag determining whether tracking protection should be enabled. Default is
   *     false.
   */
  public void setUseTrackingProtection(final boolean value) {
    setBoolean(USE_TRACKING_PROTECTION, value);
  }

  /**
   * Set the privacy mode for this instance.
   *
   * @param value A flag determining whether Private Mode should be enabled. Default is false.
   */
  private void setUsePrivateMode(final boolean value) {
    setBoolean(USE_PRIVATE_MODE, value);
  }

  /**
   * Set whether to suspend the playing of media when the session is inactive.
   *
   * @param value A flag determining whether media should be suspended. Default is false.
   */
  public void setSuspendMediaWhenInactive(final boolean value) {
    setBoolean(SUSPEND_MEDIA_WHEN_INACTIVE, value);
  }

  /**
   * Set whether JavaScript support should be enabled.
   *
   * @param value A flag determining whether JavaScript should be enabled. Default is true.
   */
  public void setAllowJavascript(final boolean value) {
    setBoolean(ALLOW_JAVASCRIPT, value);
  }

  /**
   * Set whether the entire accessible tree should be exposed with no caching.
   *
   * @param value A flag determining full accessibility tree should be exposed. Default is false.
   */
  public void setFullAccessibilityTree(final boolean value) {
    setBoolean(FULL_ACCESSIBILITY_TREE, value);
  }

  /* package */ void setIsPopup(final boolean value) {
    setBoolean(IS_POPUP, value);
  }

  private void setBoolean(final Key<Boolean> key, final boolean value) {
    synchronized (mBundle) {
      if (valueChangedLocked(key, value)) {
        mBundle.putBoolean(key.name, value);
        dispatchUpdate();
      }
    }
  }

  /**
   * Whether tracking protection is enabled.
   *
   * @return true if tracking protection is enabled, false if not.
   */
  public boolean getUseTrackingProtection() {
    return getBoolean(USE_TRACKING_PROTECTION);
  }

  /**
   * Whether private mode is enabled.
   *
   * @return true if private mode is enabled, false if not.
   */
  public boolean getUsePrivateMode() {
    return getBoolean(USE_PRIVATE_MODE);
  }

  /**
   * The context ID for this session.
   *
   * @return The context ID for this session.
   */
  public @Nullable String getContextId() {
    // Return the user-provided unsafe string.
    return getString(UNSAFE_CONTEXT_ID);
  }

  /**
   * Whether media will be suspended when the session is inactice.
   *
   * @return true if media will be suspended, false if not.
   */
  public boolean getSuspendMediaWhenInactive() {
    return getBoolean(SUSPEND_MEDIA_WHEN_INACTIVE);
  }

  /**
   * Whether javascript execution is allowed.
   *
   * @return true if javascript execution is allowed, false if not.
   */
  public boolean getAllowJavascript() {
    return getBoolean(ALLOW_JAVASCRIPT);
  }

  /**
   * Whether entire accessible tree is exposed with no caching.
   *
   * @return true if accessibility tree is exposed, false if not.
   */
  public boolean getFullAccessibilityTree() {
    return getBoolean(FULL_ACCESSIBILITY_TREE);
  }

  /* package */ boolean getIsPopup() {
    return getBoolean(IS_POPUP);
  }

  private boolean getBoolean(final Key<Boolean> key) {
    synchronized (mBundle) {
      return mBundle.getBoolean(key.name);
    }
  }

  /**
   * Set the screen id.
   *
   * @param value The screen id.
   */
  private void setScreenId(final int value) {
    setInt(SCREEN_ID, value);
  }

  /**
   * Specify which user agent mode we should use
   *
   * @param value One or more of the {@link GeckoSessionSettings#USER_AGENT_MODE_MOBILE
   *     GeckoSessionSettings.USER_AGENT_MODE_*} flags.
   */
  public void setUserAgentMode(@UserAgentMode final int value) {
    setInt(USER_AGENT_MODE, value);
  }

  /**
   * Set the display mode.
   *
   * @param value The mode to set the display to. Use one or more of the {@link
   *     GeckoSessionSettings#DISPLAY_MODE_BROWSER GeckoSessionSettings.DISPLAY_MODE_*} flags.
   */
  public void setDisplayMode(@DisplayMode final int value) {
    setInt(DISPLAY_MODE, value);
  }

  /**
   * Specify which viewport mode we should use
   *
   * @param value One or more of the {@link GeckoSessionSettings#VIEWPORT_MODE_MOBILE
   *     GeckoSessionSettings.VIEWPORT_MODE_*} flags.
   */
  public void setViewportMode(@ViewportMode final int value) {
    setInt(VIEWPORT_MODE, value);
  }

  private void setInt(final Key<Integer> key, final int value) {
    synchronized (mBundle) {
      if (valueChangedLocked(key, value)) {
        mBundle.putInt(key.name, value);
        dispatchUpdate();
      }
    }
  }

  /**
   * Set the window screen ID. Read-only once session is open. Use the {@link Builder} to set on
   * session open.
   *
   * @return Key to set the window screen ID. 0 is the default ID.
   */
  public int getScreenId() {
    return getInt(SCREEN_ID);
  }

  /**
   * The current user agent Mode
   *
   * @return One or more of the {@link GeckoSessionSettings#USER_AGENT_MODE_MOBILE
   *     GeckoSessionSettings.USER_AGENT_MODE_*} flags.
   */
  public @UserAgentMode int getUserAgentMode() {
    return getInt(USER_AGENT_MODE);
  }

  /**
   * The current display mode.
   *
   * @return One or more of the {@link GeckoSessionSettings#DISPLAY_MODE_BROWSER
   *     GeckoSessionSettings.DISPLAY_MODE_*} flags.
   */
  public @DisplayMode int getDisplayMode() {
    return getInt(DISPLAY_MODE);
  }

  /**
   * The current viewport Mode
   *
   * @return One or more of the {@link GeckoSessionSettings#VIEWPORT_MODE
   *     GeckoSessionSettings.VIEWPORT_MODE_*} flags.
   */
  public @ViewportMode int getViewportMode() {
    return getInt(VIEWPORT_MODE);
  }

  private int getInt(final Key<Integer> key) {
    synchronized (mBundle) {
      return mBundle.getInt(key.name);
    }
  }

  /**
   * Set the chrome URI.
   *
   * @param value The URI to set the Chrome URI to.
   */
  private void setChromeUri(final @NonNull String value) {
    setString(CHROME_URI, value);
  }

  /**
   * Specify the user agent override string. Set value to null to use the user agent specified by
   * USER_AGENT_MODE.
   *
   * @param value The string to override the user agent with.
   */
  public void setUserAgentOverride(final @Nullable String value) {
    setString(USER_AGENT_OVERRIDE, value);
  }

  private void setContextId(final @Nullable String value) {
    setString(UNSAFE_CONTEXT_ID, value);
    setString(CONTEXT_ID, StorageController.createSafeSessionContextId(value));
  }

  private void setString(final Key<String> key, final String value) {
    synchronized (mBundle) {
      if (valueChangedLocked(key, value)) {
        mBundle.putString(key.name, value);
        dispatchUpdate();
      }
    }
  }

  /**
   * Set the chrome window URI. Read-only once session is open. Use the {@link Builder} to set on
   * session open.
   *
   * @return Key to set the chrome window URI, or null to use default URI.
   */
  public @Nullable String getChromeUri() {
    return getString(CHROME_URI);
  }

  /**
   * The user agent override string.
   *
   * @return The current user agent string or null if the agent is specified by {@link
   *     GeckoSessionSettings#USER_AGENT_MODE}
   */
  public @Nullable String getUserAgentOverride() {
    return getString(USER_AGENT_OVERRIDE);
  }

  private String getString(final Key<String> key) {
    synchronized (mBundle) {
      return mBundle.getString(key.name);
    }
  }

  /* package */ @NonNull
  GeckoBundle toBundle() {
    return new GeckoBundle(mBundle);
  }

  @Override
  public String toString() {
    return mBundle.toString();
  }

  @Override
  public boolean equals(final Object other) {
    return other instanceof GeckoSessionSettings
        && mBundle.equals(((GeckoSessionSettings) other).mBundle);
  }

  @Override
  public int hashCode() {
    return mBundle.hashCode();
  }

  private <T> boolean valueChangedLocked(final Key<T> key, final T value) {
    if (key.initOnly && mSession != null) {
      throw new IllegalStateException("Read-only property");
    } else if (key.values != null && !key.values.contains(value)) {
      throw new IllegalArgumentException("Invalid value");
    }

    final Object old = mBundle.get(key.name);
    return (old != value) && (old == null || !old.equals(value));
  }

  private void dispatchUpdate() {
    if (mSession != null) {
      mSession.getEventDispatcher().dispatch("GeckoView:UpdateSettings", toBundle());
    }
  }

  @Override // Parcelable
  public int describeContents() {
    return 0;
  }

  @Override // Parcelable
  public void writeToParcel(final @NonNull Parcel out, final int flags) {
    mBundle.writeToParcel(out, flags);
  }

  // AIDL code may call readFromParcel even though it's not part of Parcelable.
  @SuppressWarnings("checkstyle:javadocmethod")
  public void readFromParcel(final @NonNull Parcel source) {
    mBundle.readFromParcel(source);
  }

  public static final Parcelable.Creator<GeckoSessionSettings> CREATOR =
      new Parcelable.Creator<GeckoSessionSettings>() {
        @Override
        public GeckoSessionSettings createFromParcel(final Parcel in) {
          final GeckoSessionSettings settings = new GeckoSessionSettings();
          settings.readFromParcel(in);
          return settings;
        }

        @Override
        public GeckoSessionSettings[] newArray(final int size) {
          return new GeckoSessionSettings[size];
        }
      };
}