/*
 * Copyright (C) 2016 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.emergency.view;

import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentActivity;
import androidx.fragment.app.FragmentManager;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import androidx.annotation.LayoutRes;
import android.os.UserHandle;
import android.os.UserManager;
import com.google.android.material.tabs.TabLayout;
import com.google.android.material.tabs.TabLayout.TabLayoutOnPageChangeListener;
import com.google.android.material.tabs.TabLayout.ViewPagerOnTabSelectedListener;
import androidx.fragment.app.FragmentStatePagerAdapter;
import androidx.viewpager.widget.ViewPager;
import androidx.preference.PreferenceManager;

import android.provider.Settings;
import android.text.TextUtils;
import android.util.Log;
import android.util.Pair;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toolbar;
import android.widget.ViewFlipper;

import com.android.emergency.CircleFramedDrawable;
import com.android.emergency.R;
import com.android.emergency.edit.EditInfoActivity;
import com.android.emergency.util.PreferenceUtils;
import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.logging.MetricsLogger;
import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
import com.android.internal.util.UserIcons;

import java.util.ArrayList;

/**
 * Activity for viewing emergency information.
 */
public class ViewInfoActivity extends FragmentActivity {

    private static final String TAG = "ViewInfoActivity";

    private ImageView mPersonalCardLargeIcon;
    private TextView mPersonalCardLargeItem;
    private SharedPreferences mSharedPreferences;
    private LinearLayout mPersonalCard;
    private ViewFlipper mViewFlipper;
    private ViewPagerAdapter mTabsAdapter;
    private TabLayout mTabLayout;
    private ArrayList<Pair<String, Fragment>> mFragments;
    private Menu mMenu;

    @Override
    public void setContentView(@LayoutRes int layoutResID) {
        super.setContentView(layoutResID);
        setupTabs();
        Toolbar toolbar = (Toolbar) findViewById(R.id.action_bar);
        setActionBar(toolbar);
        getActionBar().setDisplayHomeAsUpEnabled(true);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.view_activity_layout);
        mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
        mPersonalCard = (LinearLayout) findViewById(R.id.name_and_dob_linear_layout);
        mPersonalCardLargeIcon = (ImageView) findViewById(R.id.personal_card_icon);
        mPersonalCardLargeItem = (TextView) findViewById(R.id.personal_card_large);
        mViewFlipper = (ViewFlipper) findViewById(R.id.view_flipper);

        MetricsLogger.visible(this, MetricsEvent.ACTION_VIEW_EMERGENCY_INFO);
    }

    @Override
    public void onResume() {
        super.onResume();
        loadUserInfo();
        // Update the tabs: new info might have been added/deleted from the edit screen that
        // could lead to adding/removing a fragment
        setupTabs();
        maybeHideTabs();
    }

    private void loadUserInfo() {
        UserManager userManager = getSystemService(UserManager.class);
        if (TextUtils.isEmpty(userManager.getUserName())) {
            mPersonalCard.setVisibility(View.GONE);
        } else {
            mPersonalCard.setVisibility(View.VISIBLE);
            mPersonalCardLargeItem.setText(userManager.getUserName());

            Bitmap bitmapUserIcon = userManager.getUserIcon(UserHandle.myUserId());

            if (bitmapUserIcon == null) {
                // Get default user icon.
                Drawable defaultUserIcon = UserIcons.getDefaultUserIcon(
                        getApplicationContext().getResources(), UserHandle.myUserId(),
                        false /* light icon */);
                bitmapUserIcon = UserIcons.convertToBitmap(defaultUserIcon);
            }

            Drawable drawableUserIcon = new CircleFramedDrawable(bitmapUserIcon,
                    (int) getResources().getDimension(R.dimen.action_bar_size));

            mPersonalCardLargeIcon.setImageDrawable(drawableUserIcon);
        }
    }

    private void maybeHideTabs() {
        // Show a TextView with "No information provided" if there are no fragments.
        if (mFragments.size() == 0) {
            mViewFlipper.setDisplayedChild(
                    mViewFlipper.indexOfChild(findViewById(R.id.no_info)));
        } else {
            mViewFlipper.setDisplayedChild(mViewFlipper.indexOfChild(findViewById(R.id.tabs)));
        }

        TabLayout tabLayout = mTabLayout;
        if (mFragments.size() <= 1) {
            tabLayout.setVisibility(View.GONE);
        } else {
            tabLayout.setVisibility(View.VISIBLE);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        if (Settings.Secure.getInt(getContentResolver(),
                Settings.Secure.USER_SETUP_COMPLETE, 0) == 0) {
            Log.d(TAG, "Device setup not complete, not showing edit button.");
            return super.onCreateOptionsMenu(menu);
        }

        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.view_info_menu, menu);
        mMenu = menu;
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int itemId = item.getItemId();
        if (itemId == android.R.id.home) {
            onBackPressed();
            return true;
        } else if (itemId == R.id.action_edit) {
            Intent intent = new Intent(this, EditInfoActivity.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            startActivity(intent);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /** Return the tab layout. */
    @VisibleForTesting
    public TabLayout getTabLayout() {
        return mTabLayout;
    }

    @VisibleForTesting
    public Menu getMenu() {
        return mMenu;
    }

    /** Return the fragments. */
    @VisibleForTesting
    public ArrayList<Pair<String, Fragment>> getFragments() {
        return mFragments;
    }

    private ArrayList<Pair<String, Fragment>> setUpFragments() {
        // Return only the fragments that have at least one piece of information set:
        ArrayList<Pair<String, Fragment>> fragments = new ArrayList<>(2);

        if (PreferenceUtils.hasAtLeastOnePreferenceSet(this)) {
            fragments.add(Pair.create(getResources().getString(R.string.tab_title_info),
                    ViewEmergencyInfoFragment.newInstance()));
        }
        if (PreferenceUtils.hasAtLeastOneEmergencyContact(this)) {
            fragments.add(Pair.create(getResources().getString(R.string.tab_title_contacts),
                    ViewEmergencyContactsFragment.newInstance()));
        }
        return fragments;
    }

    private void setupTabs() {
        mFragments = setUpFragments();
        mTabLayout = (TabLayout) findViewById(R.id.sliding_tabs);
        if (mTabsAdapter == null) {
            // The viewpager that will host the section contents.
            ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
            mTabsAdapter = new ViewPagerAdapter(getSupportFragmentManager());
            viewPager.setAdapter(mTabsAdapter);
            mTabLayout.setTabsFromPagerAdapter(mTabsAdapter);

            // Set a listener via setOnTabSelectedListener(OnTabSelectedListener) to be notified
            // when any tab's selection state has been changed.
            mTabLayout.setOnTabSelectedListener(
                    new TabLayout.ViewPagerOnTabSelectedListener(viewPager));

            // Use a TabLayout.TabLayoutOnPageChangeListener to forward the scroll and selection
            // changes to this layout
            viewPager.addOnPageChangeListener(new TabLayoutOnPageChangeListener(mTabLayout));
        } else {
            mTabsAdapter.notifyDataSetChanged();
            mTabLayout.setTabsFromPagerAdapter(mTabsAdapter);
        }
    }

    /** The adapter used to handle the two fragments. */
    protected class ViewPagerAdapter extends FragmentStatePagerAdapter {
        public ViewPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            return mFragments.get(position).second;
        }

        @Override
        public int getCount() {
            return mFragments.size();
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return mFragments.get(position).first;
        }

        @Override
        public int getItemPosition(Object object) {
            // The default implementation assumes that items will never change position and always
            // returns POSITION_UNCHANGED. This is how you can specify that the positions can change
            return FragmentStatePagerAdapter.POSITION_NONE;
        }
    }
}