/*
 * Copyright (C) 2023 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.systemui.car.userpicker;

import static android.view.WindowManager.LayoutParams.SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS;
import static android.window.OnBackInvokedDispatcher.PRIORITY_DEFAULT;

import static com.android.systemui.car.userpicker.HeaderState.HEADER_STATE_CHANGE_USER;
import static com.android.systemui.car.userpicker.HeaderState.HEADER_STATE_LOGOUT;
import static com.android.systemui.car.users.CarSystemUIUserUtil.isMUPANDSystemUI;

import android.app.Activity;
import android.content.Context;
import android.content.res.Configuration;
import android.os.Bundle;
import android.util.Log;
import android.util.Slog;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowInsets;
import android.view.WindowInsetsController;
import android.view.WindowManager;
import android.window.OnBackInvokedCallback;

import androidx.annotation.NonNull;
import androidx.annotation.VisibleForTesting;
import androidx.recyclerview.widget.GridLayoutManager;

import com.android.car.ui.recyclerview.CarUiRecyclerView;
import com.android.systemui.Dumpable;
import com.android.systemui.R;
import com.android.systemui.car.CarServiceProvider;
import com.android.systemui.car.systembar.element.CarSystemBarElementInitializer;
import com.android.systemui.car.userpicker.UserPickerController.Callbacks;
import com.android.systemui.dump.DumpManager;
import com.android.systemui.settings.DisplayTracker;

import java.io.PrintWriter;
import java.util.List;

import javax.inject.Inject;

/**
 * Main activity for user picker.
 *
 * <p>This class uses the Trampoline pattern to ensure the activity is executed as user 0.
 * It has user picker controller object for the executed display, and cleans it up
 * when the activity is destroyed.
 */
public class UserPickerActivity extends Activity implements Dumpable {
    private static final String TAG = UserPickerActivity.class.getSimpleName();
    private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);

    private UserPickerActivityComponent mUserPickerActivityComponent;
    private boolean mIsDriver;

    @Inject
    CarSystemBarElementInitializer mCarSystemBarElementInitializer;
    @Inject
    DisplayTracker mDisplayTracker;
    @Inject
    DumpManager mDumpManager;

    @VisibleForTesting
    UserPickerController mController;
    @VisibleForTesting
    SnackbarManager mSnackbarManager;
    @VisibleForTesting
    DialogManager mDialogManager;
    @VisibleForTesting
    UserPickerAdapter mAdapter;
    @VisibleForTesting
    CarUiRecyclerView mUserPickerView;
    @VisibleForTesting
    View mRootView;
    @VisibleForTesting
    View mHeaderBarTextForLogout;
    @VisibleForTesting
    View mLogoutButton;
    @VisibleForTesting
    View mBackButton;

    private final OnBackInvokedCallback mIgnoreBackCallback = () -> {
        // Ignore back press.
        if (DEBUG) Log.d(TAG, "Skip Back");
    };

    @Inject
    UserPickerActivity(
            Context context, //application context
            DisplayTracker displayTracker,
            CarServiceProvider carServiceProvider,
            UserPickerSharedState userPickerSharedState
    ) {
        this();
        mUserPickerActivityComponent = DaggerUserPickerActivityComponent.builder()
                .context(context)
                .carServiceProvider(carServiceProvider)
                .displayTracker(displayTracker)
                .userPickerSharedState(userPickerSharedState)
                .build();
        //Component.inject(this) is not working because constructor and activity itself is
        //scoped to SystemUiScope but the deps below are scoped to UserPickerScope
        mDialogManager = mUserPickerActivityComponent.dialogManager();
        mSnackbarManager = mUserPickerActivityComponent.snackbarManager();
        mController = mUserPickerActivityComponent.userPickerController();
    }

    @VisibleForTesting
    UserPickerActivity() {
        super();
    }

    private final Callbacks mCallbacks = new Callbacks() {
        @Override
        public void onUpdateUsers(List<UserRecord> users) {
            mAdapter.updateUsers(users);
            mAdapter.notifyDataSetChanged();
        }

        @Override
        public void onHeaderStateChanged(HeaderState headerState) {
            setupHeaderBar(headerState);
        }

        @Override
        public void onFinishRequested() {
            finishAndRemoveTask();
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        if (shouldStartAsSystemUser()
                && !ActivityHelper.startUserPickerAsUserSystem(this)) {
            super.onCreate(savedInstanceState);
            return;
        }

        if (DEBUG) {
            Slog.d(TAG, "onCreate: userId=" + getUserId() + " displayId=" + getDisplayId());
        }

        super.onCreate(savedInstanceState);
        setShowWhenLocked(true);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getOnBackInvokedDispatcher()
                .registerOnBackInvokedCallback(PRIORITY_DEFAULT, mIgnoreBackCallback);
        init();
    }

    @VisibleForTesting
    void init() {
        mIsDriver = getIsDriver();
        LayoutInflater inflater = LayoutInflater.from(this);
        mRootView = inflater.inflate(R.layout.user_picker, null);
        if (getWindow() != null) {
            setContentView(mRootView);
            initWindow();
        }

        initManagers(mRootView);
        initViews();
        initController();

        mController.onConfigurationChanged();
        String dumpableName = TAG + "#" + getDisplayId();
        mDumpManager.unregisterDumpable(dumpableName);
        mDumpManager.registerNormalDumpable(dumpableName, /* module= */ this);
    }

    @Override
    protected void onStart() {
        super.onStart();
        getWindow().addSystemFlags(SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS);
    }

    private void initViews() {
        View powerBtn = mRootView.findViewById(R.id.power_button_icon_view);
        powerBtn.setOnClickListener(v -> mController.screenOffDisplay());
        if (mIsDriver) {
            powerBtn.setVisibility(View.GONE);
        }
        mHeaderBarTextForLogout = mRootView.findViewById(R.id.message);

        mLogoutButton = mRootView.findViewById(R.id.logout_button_icon_view);
        mLogoutButton.setOnClickListener(v -> mController.logoutUser());

        mBackButton = mRootView.findViewById(R.id.back_button);
        mBackButton.setOnClickListener(v -> {
            finishAndRemoveTask();
        });

        initRecyclerView();

        // Initialize bar element within the user picker's bottom bar
        View bottomBar = mRootView.findViewById(R.id.user_picker_bottom_bar);
        if (bottomBar instanceof ViewGroup) {
            mCarSystemBarElementInitializer.initializeCarSystemBarElements((ViewGroup) bottomBar);
        }
    }

    private void initRecyclerView() {
        int numCols = getResources().getInteger(R.integer.user_fullscreen_switcher_num_col);
        mUserPickerView = mRootView.findViewById(R.id.user_picker);
        mUserPickerView.setLayoutManager(new GridLayoutManager(this, numCols));
        mAdapter = createUserPickerAdapter();
        mUserPickerView.setAdapter(mAdapter);
    }

    private void initWindow() {
        Window window = getWindow();
        WindowInsetsController insetsController = window.getInsetsController();
        if (insetsController != null) {
            insetsController.setAnimationsDisabled(true);
            insetsController.hide(WindowInsets.Type.statusBars()
                    | WindowInsets.Type.navigationBars());
        }
    }

    private void initManagers(View rootView) {
        mDialogManager.initContextFromView(rootView);
        mSnackbarManager.setRootView(rootView, R.id.user_picker_bottom_bar);
    }

    private void initController() {
        mController.init(mCallbacks, getDisplayId());
    }

    @VisibleForTesting
    UserPickerAdapter createUserPickerAdapter() {
        return new UserPickerAdapter(this);
    }

    @VisibleForTesting
    boolean shouldStartAsSystemUser() {
        return true;
    }

    @VisibleForTesting
    boolean getIsDriver() {
        return !isMUPANDSystemUI() && getDisplayId() == mDisplayTracker.getDefaultDisplayId();
    }

    @Override
    protected void onStop() {
        Window window = getWindow();
        WindowManager.LayoutParams attrs = window.getAttributes();
        attrs.privateFlags &= ~SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS;
        window.setAttributes(attrs);

        super.onStop();
    }

    @Override
    protected void onDestroy() {
        if (DEBUG) {
            Slog.d(TAG, "onDestroy: displayId=" + getDisplayId());
        }
        getOnBackInvokedDispatcher().unregisterOnBackInvokedCallback(mIgnoreBackCallback);
        if (mController != null) {
            mController.onDestroy();
        }
        if (mDialogManager != null) {
            mDialogManager.clearAllDialogs();
        }
        mDumpManager.unregisterDumpable(TAG + "#" + getDisplayId());

        super.onDestroy();
    }

    @Override
    public void onConfigurationChanged(@NonNull Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        mAdapter.onConfigurationChanged();
        mController.onConfigurationChanged();
    }

    @VisibleForTesting
    void setupHeaderBar(HeaderState headerState) {
        int state = headerState.getState();
        switch (state) {
            case HEADER_STATE_LOGOUT:
                mHeaderBarTextForLogout.setVisibility(View.VISIBLE);
                mBackButton.setVisibility(View.GONE);
                mLogoutButton.setVisibility(View.GONE);
                break;
            case HEADER_STATE_CHANGE_USER:
                mHeaderBarTextForLogout.setVisibility(View.GONE);
                mBackButton.setVisibility(View.VISIBLE);
                if (!mIsDriver) {
                    mLogoutButton.setVisibility(View.VISIBLE);
                }
                break;
        }
    }

    @Override
    public void dump(@NonNull PrintWriter pw, @NonNull String[] args) {
        if (mController != null) {
            mController.dump(pw);
        }
        if (mUserPickerView != null && mUserPickerView.getAdapter() != null) {
            ((UserPickerAdapter) mUserPickerView.getAdapter()).dump(pw);
        }
    }
}