/*
 * Copyright (C) 2017 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.popup;

import android.content.ComponentName;
import android.content.Context;
import android.os.Handler;
import android.os.UserHandle;
import android.service.notification.StatusBarNotification;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.annotation.VisibleForTesting;
import android.view.View;
import android.widget.ImageView;

import com.android.launcher3.ItemInfo;
import com.android.launcher3.Launcher;
import com.android.launcher3.R;
import com.android.launcher3.ShortcutInfo;
import com.android.launcher3.graphics.LauncherIcons;
import com.android.launcher3.notification.NotificationInfo;
import com.android.launcher3.notification.NotificationItemView;
import com.android.launcher3.notification.NotificationKeyData;
import com.android.launcher3.shortcuts.DeepShortcutManager;
import com.android.launcher3.shortcuts.DeepShortcutView;
import com.android.launcher3.shortcuts.ShortcutInfoCompat;
import com.android.launcher3.util.PackageUserKey;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

/**
 * Contains logic relevant to populating a {@link PopupContainerWithArrow}. In particular,
 * this class determines which items appear in the container, and in what order.
 */
public class PopupPopulator {

    public static final int MAX_ITEMS = 4;
    @VisibleForTesting static final int NUM_DYNAMIC = 2;
    private static final int MAX_SHORTCUTS_IF_NOTIFICATIONS = 2;

    public enum Item {
        SHORTCUT(R.layout.deep_shortcut, true),
        NOTIFICATION(R.layout.notification, false),
        SYSTEM_SHORTCUT(R.layout.system_shortcut, true),
        SYSTEM_SHORTCUT_ICON(R.layout.system_shortcut_icon_only, true);

        public final int layoutId;
        public final boolean isShortcut;

        Item(int layoutId, boolean isShortcut) {
            this.layoutId = layoutId;
            this.isShortcut = isShortcut;
        }
    }

    public static @NonNull Item[] getItemsToPopulate(@NonNull List<String> shortcutIds,
            @NonNull List<NotificationKeyData> notificationKeys,
            @NonNull List<SystemShortcut> systemShortcuts) {
        boolean hasNotifications = notificationKeys.size() > 0;
        int numNotificationItems = hasNotifications ? 1 : 0;
        int numShortcuts = shortcutIds.size();
        if (hasNotifications && numShortcuts > MAX_SHORTCUTS_IF_NOTIFICATIONS) {
            numShortcuts = MAX_SHORTCUTS_IF_NOTIFICATIONS;
        }
        int numItems = Math.min(MAX_ITEMS, numShortcuts + numNotificationItems)
                + systemShortcuts.size();
        Item[] items = new Item[numItems];
        for (int i = 0; i < numItems; i++) {
            items[i] = Item.SHORTCUT;
        }
        if (hasNotifications) {
            // The notification layout is always first.
            items[0] = Item.NOTIFICATION;
        }
        // The system shortcuts are always last.
        boolean iconsOnly = !shortcutIds.isEmpty();
        for (int i = 0; i < systemShortcuts.size(); i++) {
            items[numItems - 1 - i] = iconsOnly ? Item.SYSTEM_SHORTCUT_ICON : Item.SYSTEM_SHORTCUT;
        }
        return items;
    }

    public static Item[] reverseItems(Item[] items) {
        if (items == null) return null;
        int numItems = items.length;
        Item[] reversedArray = new Item[numItems];
        for (int i = 0; i < numItems; i++) {
            reversedArray[i] = items[numItems - i - 1];
        }
        return reversedArray;
    }

    /**
     * Sorts shortcuts in rank order, with manifest shortcuts coming before dynamic shortcuts.
     */
    private static final Comparator<ShortcutInfoCompat> SHORTCUT_RANK_COMPARATOR
            = new Comparator<ShortcutInfoCompat>() {
        @Override
        public int compare(ShortcutInfoCompat a, ShortcutInfoCompat b) {
            if (a.isDeclaredInManifest() && !b.isDeclaredInManifest()) {
                return -1;
            }
            if (!a.isDeclaredInManifest() && b.isDeclaredInManifest()) {
                return 1;
            }
            return Integer.compare(a.getRank(), b.getRank());
        }
    };

    /**
     * Filters the shortcuts so that only MAX_ITEMS or fewer shortcuts are retained.
     * We want the filter to include both static and dynamic shortcuts, so we always
     * include NUM_DYNAMIC dynamic shortcuts, if at least that many are present.
     *
     * @param shortcutIdToRemoveFirst An id that should be filtered out first, if any.
     * @return a subset of shortcuts, in sorted order, with size <= MAX_ITEMS.
     */
    public static List<ShortcutInfoCompat> sortAndFilterShortcuts(
            List<ShortcutInfoCompat> shortcuts, @Nullable String shortcutIdToRemoveFirst) {
        // Remove up to one specific shortcut before sorting and doing somewhat fancy filtering.
        if (shortcutIdToRemoveFirst != null) {
            Iterator<ShortcutInfoCompat> shortcutIterator = shortcuts.iterator();
            while (shortcutIterator.hasNext()) {
                if (shortcutIterator.next().getId().equals(shortcutIdToRemoveFirst)) {
                    shortcutIterator.remove();
                    break;
                }
            }
        }

        Collections.sort(shortcuts, SHORTCUT_RANK_COMPARATOR);
        if (shortcuts.size() <= MAX_ITEMS) {
            return shortcuts;
        }

        // The list of shortcuts is now sorted with static shortcuts followed by dynamic
        // shortcuts. We want to preserve this order, but only keep MAX_ITEMS.
        List<ShortcutInfoCompat> filteredShortcuts = new ArrayList<>(MAX_ITEMS);
        int numDynamic = 0;
        int size = shortcuts.size();
        for (int i = 0; i < size; i++) {
            ShortcutInfoCompat shortcut = shortcuts.get(i);
            int filteredSize = filteredShortcuts.size();
            if (filteredSize < MAX_ITEMS) {
                // Always add the first MAX_ITEMS to the filtered list.
                filteredShortcuts.add(shortcut);
                if (shortcut.isDynamic()) {
                    numDynamic++;
                }
                continue;
            }
            // At this point, we have MAX_ITEMS already, but they may all be static.
            // If there are dynamic shortcuts, remove static shortcuts to add them.
            if (shortcut.isDynamic() && numDynamic < NUM_DYNAMIC) {
                numDynamic++;
                int lastStaticIndex = filteredSize - numDynamic;
                filteredShortcuts.remove(lastStaticIndex);
                filteredShortcuts.add(shortcut);
            }
        }
        return filteredShortcuts;
    }

    public static Runnable createUpdateRunnable(final Launcher launcher, final ItemInfo originalInfo,
            final Handler uiHandler, final PopupContainerWithArrow container,
            final List<String> shortcutIds, final List<DeepShortcutView> shortcutViews,
            final List<NotificationKeyData> notificationKeys,
            final NotificationItemView notificationView, final List<SystemShortcut> systemShortcuts,
            final List<View> systemShortcutViews) {
        final ComponentName activity = originalInfo.getTargetComponent();
        final UserHandle user = originalInfo.user;
        return new Runnable() {
            @Override
            public void run() {
                if (notificationView != null) {
                    List<StatusBarNotification> notifications = launcher.getPopupDataProvider()
                            .getStatusBarNotificationsForKeys(notificationKeys);
                    List<NotificationInfo> infos = new ArrayList<>(notifications.size());
                    for (int i = 0; i < notifications.size(); i++) {
                        StatusBarNotification notification = notifications.get(i);
                        infos.add(new NotificationInfo(launcher, notification));
                    }
                    uiHandler.post(new UpdateNotificationChild(notificationView, infos));
                }

                List<ShortcutInfoCompat> shortcuts = DeepShortcutManager.getInstance(launcher)
                        .queryForShortcutsContainer(activity, shortcutIds, user);
                String shortcutIdToDeDupe = notificationKeys.isEmpty() ? null
                        : notificationKeys.get(0).shortcutId;
                shortcuts = PopupPopulator.sortAndFilterShortcuts(shortcuts, shortcutIdToDeDupe);
                for (int i = 0; i < shortcuts.size() && i < shortcutViews.size(); i++) {
                    final ShortcutInfoCompat shortcut = shortcuts.get(i);
                    ShortcutInfo si = new ShortcutInfo(shortcut, launcher);
                    // Use unbadged icon for the menu.
                    si.iconBitmap = LauncherIcons.createShortcutIcon(
                            shortcut, launcher, false /* badged */);
                    si.rank = i;
                    uiHandler.post(new UpdateShortcutChild(container, shortcutViews.get(i),
                            si, shortcut));
                }

                // This ensures that mLauncher.getWidgetsForPackageUser()
                // doesn't return null (it puts all the widgets in memory).
                for (int i = 0; i < systemShortcuts.size(); i++) {
                    final SystemShortcut systemShortcut = systemShortcuts.get(i);
                    uiHandler.post(new UpdateSystemShortcutChild(container,
                            systemShortcutViews.get(i), systemShortcut, launcher, originalInfo));
                }
                uiHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        launcher.refreshAndBindWidgetsForPackageUser(
                                PackageUserKey.fromItemInfo(originalInfo));
                    }
                });
            }
        };
    }

    /** Updates the shortcut child of this container based on the given shortcut info. */
    private static class UpdateShortcutChild implements Runnable {
        private final PopupContainerWithArrow mContainer;
        private final DeepShortcutView mShortcutChild;
        private final ShortcutInfo mShortcutChildInfo;
        private final ShortcutInfoCompat mDetail;

        public UpdateShortcutChild(PopupContainerWithArrow container, DeepShortcutView shortcutChild,
                ShortcutInfo shortcutChildInfo, ShortcutInfoCompat detail) {
            mContainer = container;
            mShortcutChild = shortcutChild;
            mShortcutChildInfo = shortcutChildInfo;
            mDetail = detail;
        }

        @Override
        public void run() {
            mShortcutChild.applyShortcutInfo(mShortcutChildInfo, mDetail,
                    mContainer.mShortcutsItemView);
        }
    }

    /** Updates the notification child based on the given notification info. */
    private static class UpdateNotificationChild implements Runnable {
        private NotificationItemView mNotificationView;
        private List<NotificationInfo> mNotificationInfos;

        public UpdateNotificationChild(NotificationItemView notificationView,
                List<NotificationInfo> notificationInfos) {
            mNotificationView = notificationView;
            mNotificationInfos = notificationInfos;
        }

        @Override
        public void run() {
            mNotificationView.applyNotificationInfos(mNotificationInfos);
        }
    }

    /** Updates the system shortcut child based on the given shortcut info. */
    private static class UpdateSystemShortcutChild implements Runnable {

        private final PopupContainerWithArrow mContainer;
        private final View mSystemShortcutChild;
        private final SystemShortcut mSystemShortcutInfo;
        private final Launcher mLauncher;
        private final ItemInfo mItemInfo;

        public UpdateSystemShortcutChild(PopupContainerWithArrow container, View systemShortcutChild,
                SystemShortcut systemShortcut, Launcher launcher, ItemInfo originalInfo) {
            mContainer = container;
            mSystemShortcutChild = systemShortcutChild;
            mSystemShortcutInfo = systemShortcut;
            mLauncher = launcher;
            mItemInfo = originalInfo;
        }

        @Override
        public void run() {
            final Context context = mSystemShortcutChild.getContext();
            initializeSystemShortcut(context, mSystemShortcutChild, mSystemShortcutInfo);
            mSystemShortcutChild.setOnClickListener(mSystemShortcutInfo
                    .getOnClickListener(mLauncher, mItemInfo));
        }
    }

    public static void initializeSystemShortcut(Context context, View view, SystemShortcut info) {
        if (view instanceof DeepShortcutView) {
            // Expanded system shortcut, with both icon and text shown on white background.
            final DeepShortcutView shortcutView = (DeepShortcutView) view;
            shortcutView.getIconView().setBackground(info.getIcon(context,
                    android.R.attr.textColorTertiary));
            shortcutView.getBubbleText().setText(info.getLabel(context));
        } else if (view instanceof ImageView) {
            // Only the system shortcut icon shows on a gray background header.
            final ImageView shortcutIcon = (ImageView) view;
            shortcutIcon.setImageDrawable(info.getIcon(context,
                    android.R.attr.textColorHint));
            shortcutIcon.setContentDescription(info.getLabel(context));
        }
        view.setTag(info);
    }
}
