/*
 * Copyright 2018 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 androidx.core.view;

import android.app.Activity;
import android.graphics.Rect;
import android.os.Build;
import android.view.View;
import android.view.Window;

import androidx.annotation.DoNotInline;
import androidx.annotation.IdRes;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;

/**
 * Helper for accessing features in {@link Window}.
 */
public final class WindowCompat {
    /**
     * Flag for enabling the Action Bar.
     * This is enabled by default for some devices. The Action Bar
     * replaces the title bar and provides an alternate location
     * for an on-screen menu button on some devices.
     */
    public static final int FEATURE_ACTION_BAR = 8;

    /**
     * Flag for requesting an Action Bar that overlays window content.
     * Normally an Action Bar will sit in the space above window content, but if this
     * feature is requested along with {@link #FEATURE_ACTION_BAR} it will be layered over
     * the window content itself. This is useful if you would like your app to have more control
     * over how the Action Bar is displayed, such as letting application content scroll beneath
     * an Action Bar with a transparent background or otherwise displaying a transparent/translucent
     * Action Bar over application content.
     *
     * <p>This mode is especially useful with {@link View#SYSTEM_UI_FLAG_FULLSCREEN
     * View.SYSTEM_UI_FLAG_FULLSCREEN}, which allows you to seamlessly hide the
     * action bar in conjunction with other screen decorations.
     *
     * <p>As of {@link Build.VERSION_CODES#JELLY_BEAN}, when an
     * ActionBar is in this mode it will adjust the insets provided to
     * {@link View#fitSystemWindows(Rect) View.fitSystemWindows(Rect)}
     * to include the content covered by the action bar, so you can do layout within
     * that space.
     */
    public static final int FEATURE_ACTION_BAR_OVERLAY = 9;

    /**
     * Flag for specifying the behavior of action modes when an Action Bar is not present.
     * If overlay is enabled, the action mode UI will be allowed to cover existing window content.
     */
    public static final int FEATURE_ACTION_MODE_OVERLAY = 10;

    private WindowCompat() {}

    /**
     * Finds a view that was identified by the {@code android:id} XML attribute
     * that was processed in {@link Activity#onCreate}, or throws an
     * IllegalArgumentException if the ID is invalid, or there is no matching view in the hierarchy.
     * <p>
     * <strong>Note:</strong> In most cases -- depending on compiler support --
     * the resulting view is automatically cast to the target class type. If
     * the target class type is unconstrained, an explicit cast may be
     * necessary.
     *
     * @param window window in which to find the view.
     * @param id the ID to search for
     * @return a view with given ID
     * @see ViewCompat#requireViewById(View, int)
     * @see Window#findViewById(int)
     */
    @SuppressWarnings("TypeParameterUnusedInFormals")
    @NonNull
    public static <T extends View> T requireViewById(@NonNull Window window, @IdRes int id) {
        if (Build.VERSION.SDK_INT >= 28) {
            return Api28Impl.requireViewById(window, id);
        }

        T view = window.findViewById(id);
        if (view == null) {
            throw new IllegalArgumentException("ID does not reference a View inside this Window");
        }
        return view;
    }

    /**
     * Sets whether the decor view should fit root-level content views for
     * {@link WindowInsetsCompat}.
     * <p>
     * If set to {@code false}, the framework will not fit the content view to the insets and will
     * just pass through the {@link WindowInsetsCompat} to the content view.
     * </p>
     * <p>
     * Please note: using the {@link View#setSystemUiVisibility(int)} API in your app can
     * conflict with this method. Please discontinue use of {@link View#setSystemUiVisibility(int)}.
     * </p>
     *
     * @param window                 The current window.
     * @param decorFitsSystemWindows Whether the decor view should fit root-level content views for
     *                               insets.
     */
    public static void setDecorFitsSystemWindows(@NonNull Window window,
            final boolean decorFitsSystemWindows) {
        if (Build.VERSION.SDK_INT >= 30) {
            Api30Impl.setDecorFitsSystemWindows(window, decorFitsSystemWindows);
        } else if (Build.VERSION.SDK_INT >= 16) {
            Api16Impl.setDecorFitsSystemWindows(window, decorFitsSystemWindows);
        }
    }

    /**
     * Retrieves the single {@link WindowInsetsControllerCompat} of the window this view is attached
     * to.
     *
     * @return The {@link WindowInsetsControllerCompat} for the window.
     * @see Window#getInsetsController()
     */
    @NonNull
    public static WindowInsetsControllerCompat getInsetsController(@NonNull Window window,
            @NonNull View view) {
        return new WindowInsetsControllerCompat(window, view);
    }

    @RequiresApi(16)
    static class Api16Impl {
        private Api16Impl() {
            // This class is not instantiable.
        }

        @DoNotInline
        static void setDecorFitsSystemWindows(@NonNull Window window,
                final boolean decorFitsSystemWindows) {
            final int decorFitsFlags = View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN;

            final View decorView = window.getDecorView();
            final int sysUiVis = decorView.getSystemUiVisibility();
            decorView.setSystemUiVisibility(decorFitsSystemWindows
                    ? sysUiVis & ~decorFitsFlags
                    : sysUiVis | decorFitsFlags);
        }
    }

    @RequiresApi(30)
    static class Api30Impl {
        private Api30Impl() {
            // This class is not instantiable.
        }

        @DoNotInline
        static void setDecorFitsSystemWindows(@NonNull Window window,
                final boolean decorFitsSystemWindows) {
            window.setDecorFitsSystemWindows(decorFitsSystemWindows);
        }
    }

    @RequiresApi(28)
    static class Api28Impl {
        private Api28Impl() {
            // This class is not instantiable.
        }

        @SuppressWarnings({"unchecked", "TypeParameterUnusedInFormals"})
        @DoNotInline
        static <T> T requireViewById(Window window, int id) {
            return (T) window.requireViewById(id);
        }
    }
}
