/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.launcher3;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.app.FragmentManager;
import android.content.ComponentName;
import android.content.ContentResolver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceFragment;
import android.provider.Settings;

import com.android.launcher3.graphics.IconShapeOverride;
import com.android.launcher3.notification.NotificationListener;
import com.android.launcher3.util.SettingsObserver;
import com.android.launcher3.views.ButtonPreference;

/**
 * Settings activity for Launcher. Currently implements the following setting: Allow rotation
 */
public class SettingsActivity extends Activity {

    private static final String ICON_BADGING_PREFERENCE_KEY = "pref_icon_badging";
    /** Hidden field Settings.Secure.NOTIFICATION_BADGING */
    public static final String NOTIFICATION_BADGING = "notification_badging";
    /** Hidden field Settings.Secure.ENABLED_NOTIFICATION_LISTENERS */
    private static final String NOTIFICATION_ENABLED_LISTENERS = "enabled_notification_listeners";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        if (savedInstanceState == null) {
            // Display the fragment as the main content.
            getFragmentManager().beginTransaction()
                    .replace(android.R.id.content, new LauncherSettingsFragment())
                    .commit();
        }
    }

    /**
     * This fragment shows the launcher preferences.
     */
    public static class LauncherSettingsFragment extends PreferenceFragment {

        private SystemDisplayRotationLockObserver mRotationLockObserver;
        private IconBadgingObserver mIconBadgingObserver;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            getPreferenceManager().setSharedPreferencesName(LauncherFiles.SHARED_PREFERENCES_KEY);
            addPreferencesFromResource(R.xml.launcher_preferences);

            ContentResolver resolver = getActivity().getContentResolver();

            // Setup allow rotation preference
            Preference rotationPref = findPreference(Utilities.ALLOW_ROTATION_PREFERENCE_KEY);
            if (getResources().getBoolean(R.bool.allow_rotation)) {
                // Launcher supports rotation by default. No need to show this setting.
                getPreferenceScreen().removePreference(rotationPref);
            } else {
                mRotationLockObserver = new SystemDisplayRotationLockObserver(rotationPref, resolver);

                // Register a content observer to listen for system setting changes while
                // this UI is active.
                mRotationLockObserver.register(Settings.System.ACCELEROMETER_ROTATION);

                // Initialize the UI once
                rotationPref.setDefaultValue(Utilities.getAllowRotationDefaultValue(getActivity()));
            }

            ButtonPreference iconBadgingPref =
                    (ButtonPreference) findPreference(ICON_BADGING_PREFERENCE_KEY);
            if (!Utilities.isAtLeastO()) {
                getPreferenceScreen().removePreference(
                        findPreference(SessionCommitReceiver.ADD_ICON_PREFERENCE_KEY));
                getPreferenceScreen().removePreference(iconBadgingPref);
            } else {
                // Listen to system notification badge settings while this UI is active.
                mIconBadgingObserver = new IconBadgingObserver(
                        iconBadgingPref, resolver, getFragmentManager());
                mIconBadgingObserver.register(NOTIFICATION_BADGING, NOTIFICATION_ENABLED_LISTENERS);
            }

            Preference iconShapeOverride = findPreference(IconShapeOverride.KEY_PREFERENCE);
            if (iconShapeOverride != null) {
                if (IconShapeOverride.isSupported(getActivity())) {
                    IconShapeOverride.handlePreferenceUi((ListPreference) iconShapeOverride);
                } else {
                    getPreferenceScreen().removePreference(iconShapeOverride);
                }
            }
        }

        @Override
        public void onDestroy() {
            if (mRotationLockObserver != null) {
                mRotationLockObserver.unregister();
                mRotationLockObserver = null;
            }
            if (mIconBadgingObserver != null) {
                mIconBadgingObserver.unregister();
                mIconBadgingObserver = null;
            }
            super.onDestroy();
        }
    }

    /**
     * Content observer which listens for system auto-rotate setting changes, and enables/disables
     * the launcher rotation setting accordingly.
     */
    private static class SystemDisplayRotationLockObserver extends SettingsObserver.System {

        private final Preference mRotationPref;

        public SystemDisplayRotationLockObserver(
                Preference rotationPref, ContentResolver resolver) {
            super(resolver);
            mRotationPref = rotationPref;
        }

        @Override
        public void onSettingChanged(boolean enabled) {
            mRotationPref.setEnabled(enabled);
            mRotationPref.setSummary(enabled
                    ? R.string.allow_rotation_desc : R.string.allow_rotation_blocked_desc);
        }
    }

    /**
     * Content observer which listens for system badging setting changes,
     * and updates the launcher badging setting subtext accordingly.
     */
    private static class IconBadgingObserver extends SettingsObserver.Secure
            implements Preference.OnPreferenceClickListener {

        private final ButtonPreference mBadgingPref;
        private final ContentResolver mResolver;
        private final FragmentManager mFragmentManager;

        public IconBadgingObserver(ButtonPreference badgingPref, ContentResolver resolver,
                FragmentManager fragmentManager) {
            super(resolver);
            mBadgingPref = badgingPref;
            mResolver = resolver;
            mFragmentManager = fragmentManager;
        }

        @Override
        public void onSettingChanged(boolean enabled) {
            int summary = enabled ? R.string.icon_badging_desc_on : R.string.icon_badging_desc_off;

            boolean serviceEnabled = true;
            if (enabled) {
                // Check if the listener is enabled or not.
                String enabledListeners =
                        Settings.Secure.getString(mResolver, NOTIFICATION_ENABLED_LISTENERS);
                ComponentName myListener =
                        new ComponentName(mBadgingPref.getContext(), NotificationListener.class);
                serviceEnabled = enabledListeners != null &&
                        (enabledListeners.contains(myListener.flattenToString()) ||
                                enabledListeners.contains(myListener.flattenToShortString()));
                if (!serviceEnabled) {
                    summary = R.string.title_missing_notification_access;
                }
            }
            mBadgingPref.setWidgetFrameVisible(!serviceEnabled);
            mBadgingPref.setOnPreferenceClickListener(serviceEnabled ? null : this);
            mBadgingPref.setSummary(summary);

        }

        @Override
        public boolean onPreferenceClick(Preference preference) {
            new NotificationAccessConfirmation().show(mFragmentManager, "notification_access");
            return true;
        }
    }

    public static class NotificationAccessConfirmation
            extends DialogFragment implements DialogInterface.OnClickListener {

        @Override
        public Dialog onCreateDialog(Bundle savedInstanceState) {
            final Context context = getActivity();
            String msg = context.getString(R.string.msg_missing_notification_access,
                    context.getString(R.string.derived_app_name));
            return new AlertDialog.Builder(context)
                    .setTitle(R.string.title_missing_notification_access)
                    .setMessage(msg)
                    .setNegativeButton(android.R.string.cancel, null)
                    .setPositiveButton(R.string.title_change_settings, this)
                    .create();
        }

        @Override
        public void onClick(DialogInterface dialogInterface, int i) {
            ComponentName cn = new ComponentName(getActivity(), NotificationListener.class);
            Intent intent = new Intent(Settings.ACTION_NOTIFICATION_LISTENER_SETTINGS)
                    .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                    .putExtra(":settings:fragment_args_key", cn.flattenToString());
            getActivity().startActivity(intent);
        }
    }
}