/*
 * Copyright 2015 Steven Mulder
 *
 * 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 smuldr.designsupportdemo;

import android.content.res.Configuration;
import android.os.Bundle;
import android.os.Handler;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.MenuItem;

public class MainActivity extends AppCompatActivity implements
    NavigationView.OnNavigationItemSelectedListener {

  private static final long DRAWER_CLOSE_DELAY_MS = 350;
  private static final String NAV_ITEM_ID = "navItemId";

  private final FirstFragment mFirstFragment = new FirstFragment();
  private final SecondFragment mSecondFragment = new SecondFragment();
  private final Handler mDrawerActionHandler = new Handler();
  private DrawerLayout mDrawerLayout;
  private ActionBarDrawerToggle mDrawerToggle;
  private int mNavItemId;

  @Override
  protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    // load saved navigation state if present
    if (null == savedInstanceState) {
      mNavItemId = R.id.drawer_item_1;
    } else {
      mNavItemId = savedInstanceState.getInt(NAV_ITEM_ID);
    }

    // listen for navigation events
    NavigationView navigationView = (NavigationView) findViewById(R.id.navigation);
    navigationView.setNavigationItemSelectedListener(this);

    // select the correct nav menu item
    navigationView.getMenu().findItem(mNavItemId).setChecked(true);

    // set up the hamburger icon to open and close the drawer
    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, toolbar, R.string.open,
        R.string.close);
    mDrawerLayout.setDrawerListener(mDrawerToggle);
    mDrawerToggle.syncState();

    navigate(mNavItemId);
  }

  /**
   * Performs the actual navigation logic, updating the main content fragment.
   */
  private void navigate(final int itemId) {
    switch (itemId) {
      case R.id.drawer_item_1:
        getFragmentManager()
            .beginTransaction()
            .replace(R.id.content, mFirstFragment)
            .commit();
        break;
      case R.id.drawer_item_2:
        getFragmentManager()
            .beginTransaction()
            .replace(R.id.content, mSecondFragment)
            .commit();
        break;
      default:
        // ignore
        break;
    }
  }

  /**
   * Handles clicks on the navigation menu.
   */
  @Override
  public boolean onNavigationItemSelected(final MenuItem menuItem) {
    // update highlighted item in the navigation menu
    menuItem.setChecked(true);
    mNavItemId = menuItem.getItemId();

    // allow some time after closing the drawer before performing real navigation
    // so the user can see what is happening
    mDrawerLayout.closeDrawer(GravityCompat.START);
    mDrawerActionHandler.postDelayed(new Runnable() {
      @Override
      public void run() {
        navigate(menuItem.getItemId());
      }
    }, DRAWER_CLOSE_DELAY_MS);
    return true;
  }

  @Override
  public void onConfigurationChanged(final Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    mDrawerToggle.onConfigurationChanged(newConfig);
  }

  @Override
  public boolean onOptionsItemSelected(final MenuItem item) {
    if (item.getItemId() == android.support.v7.appcompat.R.id.home) {
      return mDrawerToggle.onOptionsItemSelected(item);
    }
    return super.onOptionsItemSelected(item);
  }

  @Override
  public void onBackPressed() {
    if (mDrawerLayout.isDrawerOpen(GravityCompat.START)) {
      mDrawerLayout.closeDrawer(GravityCompat.START);
    } else {
      super.onBackPressed();
    }
  }

  @Override
  protected void onSaveInstanceState(final Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putInt(NAV_ITEM_ID, mNavItemId);
  }
}