package com.mapbox.mapboxsdk.maps;

import android.content.Context;
import android.graphics.PointF;
import android.os.Build;
import android.opengl.GLSurfaceView;
import android.os.Bundle;
import android.support.annotation.CallSuper;
import android.support.annotation.IntDef;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.annotation.UiThread;
import android.support.v4.util.LongSparseArray;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.ZoomButtonsController;

import com.mapbox.mapboxsdk.R;
import com.mapbox.mapboxsdk.annotations.Annotation;
import com.mapbox.mapboxsdk.annotations.MarkerViewManager;
import com.mapbox.mapboxsdk.constants.MapboxConstants;
import com.mapbox.mapboxsdk.constants.Style;
import com.mapbox.mapboxsdk.egl.EGLConfigChooser;
import com.mapbox.mapboxsdk.maps.renderer.MapRenderer;
import com.mapbox.mapboxsdk.maps.widgets.CompassView;
import com.mapbox.mapboxsdk.maps.widgets.MyLocationView;
import com.mapbox.mapboxsdk.maps.widgets.MyLocationViewSettings;
import com.mapbox.mapboxsdk.net.ConnectivityReceiver;
import com.mapbox.services.android.telemetry.MapboxTelemetry;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

import timber.log.Timber;

import static com.mapbox.mapboxsdk.maps.widgets.CompassView.TIME_MAP_NORTH_ANIMATION;
import static com.mapbox.mapboxsdk.maps.widgets.CompassView.TIME_WAIT_IDLE;
import static android.opengl.GLSurfaceView.RENDERMODE_WHEN_DIRTY;

/**
 * <p>
 * A {@code MapView} provides an embeddable map interface.
 * You use this class to display map information and to manipulate the map contents from your application.
 * You can center the map on a given coordinate, specify the size of the area you want to display,
 * and style the features of the map to fit your application's use case.
 * </p>
 * <p>
 * Use of {@code MapView} requires a Mapbox API access token.
 * Obtain an access token on the <a href="https://www.mapbox.com/studio/account/tokens/">Mapbox account page</a>.
 * </p>
 * <strong>Warning:</strong> Please note that you are responsible for getting permission to use the map data,
 * and for ensuring your use adheres to the relevant terms of use.
 */
public class MapView extends FrameLayout {

  private final MapCallback mapCallback = new MapCallback();
  private MapboxMap mapboxMap;

  private NativeMapView nativeMapView;
  private MapboxMapOptions mapboxMapOptions;
  private boolean destroyed;

  private MyLocationView myLocationView;
  private CompassView compassView;
  private PointF focalPoint;
  private ImageView attrView;
  private ImageView logoView;

  private MapGestureDetector mapGestureDetector;
  private MapKeyListener mapKeyListener;
  private MapZoomButtonController mapZoomButtonController;
  private Bundle savedInstanceState;
  private final CopyOnWriteArrayList<OnMapChangedListener> onMapChangedListeners = new CopyOnWriteArrayList<>();

  private GLSurfaceView glSurfaceView;

  @UiThread
  public MapView(@NonNull Context context) {
    super(context);
    initialise(context, MapboxMapOptions.createFromAttributes(context, null));
  }

  @UiThread
  public MapView(@NonNull Context context, @Nullable AttributeSet attrs) {
    super(context, attrs);
    initialise(context, MapboxMapOptions.createFromAttributes(context, attrs));
  }

  @UiThread
  public MapView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    initialise(context, MapboxMapOptions.createFromAttributes(context, attrs));
  }

  @UiThread
  public MapView(@NonNull Context context, @Nullable MapboxMapOptions options) {
    super(context);
    initialise(context, options == null ? MapboxMapOptions.createFromAttributes(context, null) : options);
  }

  private void initialise(@NonNull final Context context, @NonNull final MapboxMapOptions options) {
    if (isInEditMode()) {
      // in IDE layout editor, just return
      return;
    }
    mapboxMapOptions = options;

    // inflate view
    View view = LayoutInflater.from(context).inflate(R.layout.mapbox_mapview_internal, this);
    compassView = (CompassView) view.findViewById(R.id.compassView);
    myLocationView = (MyLocationView) view.findViewById(R.id.userLocationView);
    attrView = (ImageView) view.findViewById(R.id.attributionView);
    logoView = (ImageView) view.findViewById(R.id.logoView);

    // add accessibility support
    setContentDescription(context.getString(R.string.mapbox_mapActionDescription));
    setWillNotDraw(false);

    getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
      @Override
      public void onGlobalLayout() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
          getViewTreeObserver().removeOnGlobalLayoutListener(this);
        } else {
          getViewTreeObserver().removeGlobalOnLayoutListener(this);
        }
        initialiseDrawingSurface();
      }
    });
  }

  private void initialiseMap() {
    Context context = getContext();
    addOnMapChangedListener(mapCallback);

    // callback for focal point invalidation
    final FocalPointInvalidator focalPointInvalidator = new FocalPointInvalidator();
    focalPointInvalidator.addListener(createFocalPointChangeListener());

    // callback for registering touch listeners
    RegisterTouchListener registerTouchListener = new RegisterTouchListener();

    // callback for zooming in the camera
    CameraZoomInvalidator zoomInvalidator = new CameraZoomInvalidator();

    // callback for camera change events
    final CameraChangeDispatcher cameraChangeDispatcher = new CameraChangeDispatcher();

    // setup components for MapboxMap creation
    Projection proj = new Projection(nativeMapView);
    UiSettings uiSettings = new UiSettings(proj, focalPointInvalidator, compassView, attrView, logoView);
    TrackingSettings trackingSettings = new TrackingSettings(myLocationView, uiSettings, focalPointInvalidator,
      zoomInvalidator);
    MyLocationViewSettings myLocationViewSettings = new MyLocationViewSettings(myLocationView, proj,
      focalPointInvalidator);
    LongSparseArray<Annotation> annotationsArray = new LongSparseArray<>();
    MarkerViewManager markerViewManager = new MarkerViewManager((ViewGroup) findViewById(R.id.markerViewContainer));
    IconManager iconManager = new IconManager(nativeMapView);
    Annotations annotations = new AnnotationContainer(nativeMapView, annotationsArray);
    Markers markers = new MarkerContainer(nativeMapView, this, annotationsArray, iconManager, markerViewManager);
    Polygons polygons = new PolygonContainer(nativeMapView, annotationsArray);
    Polylines polylines = new PolylineContainer(nativeMapView, annotationsArray);
    AnnotationManager annotationManager = new AnnotationManager(nativeMapView, this, annotationsArray,
      markerViewManager, iconManager, annotations, markers, polygons, polylines);
    Transform transform = new Transform(nativeMapView, annotationManager.getMarkerViewManager(), trackingSettings,
      cameraChangeDispatcher);

    mapboxMap = new MapboxMap(nativeMapView, transform, uiSettings, trackingSettings, myLocationViewSettings, proj,
      registerTouchListener, annotationManager, cameraChangeDispatcher);
    focalPointInvalidator.addListener(mapboxMap.createFocalPointChangeListener());

    mapCallback.attachMapboxMap(mapboxMap);

    // user input
    mapGestureDetector = new MapGestureDetector(context, transform, proj, uiSettings, trackingSettings,
      annotationManager, cameraChangeDispatcher);
    mapKeyListener = new MapKeyListener(transform, trackingSettings, uiSettings);

    mapZoomButtonController = new MapZoomButtonController(new ZoomButtonsController(this));
    MapZoomControllerListener zoomListener = new MapZoomControllerListener(mapGestureDetector, uiSettings, transform);
    mapZoomButtonController.bind(uiSettings, zoomListener);

    compassView.injectCompassAnimationListener(createCompassAnimationListener(cameraChangeDispatcher));
    compassView.setOnClickListener(createCompassClickListener(cameraChangeDispatcher));
    // inject widgets with MapboxMap
    myLocationView.setMapboxMap(mapboxMap);
    attrView.setOnClickListener(new AttributionDialogManager(context, mapboxMap));

    // Ensure this view is interactable
    setClickable(true);
    setLongClickable(true);
    setFocusable(true);
    setFocusableInTouchMode(true);
    requestDisallowInterceptTouchEvent(true);

    // notify Map object about current connectivity state
    nativeMapView.setReachability(ConnectivityReceiver.instance(context).isConnected(context));

    // initialise MapboxMap
    if (savedInstanceState == null) {
      mapboxMap.initialise(context, mapboxMapOptions);
    } else {
      mapboxMap.onRestoreInstanceState(savedInstanceState);
    }
  }

  private FocalPointChangeListener createFocalPointChangeListener() {
    return new FocalPointChangeListener() {
      @Override
      public void onFocalPointChanged(PointF pointF) {
        focalPoint = pointF;
      }
    };
  }

  private MapboxMap.OnCompassAnimationListener createCompassAnimationListener(final CameraChangeDispatcher
                                                                                cameraChangeDispatcher) {
    return new MapboxMap.OnCompassAnimationListener() {
      @Override
      public void onCompassAnimation() {
        cameraChangeDispatcher.onCameraMove();
      }

      @Override
      public void onCompassAnimationFinished() {
        compassView.isAnimating(false);
        cameraChangeDispatcher.onCameraIdle();
      }
    };
  }

  private OnClickListener createCompassClickListener(final CameraChangeDispatcher cameraChangeDispatcher) {
    return new OnClickListener() {
      @Override
      public void onClick(View v) {
        if (mapboxMap != null && compassView != null) {
          if (focalPoint != null) {
            mapboxMap.setFocalBearing(0, focalPoint.x, focalPoint.y, TIME_MAP_NORTH_ANIMATION);
          } else {
            mapboxMap.setFocalBearing(0, mapboxMap.getWidth() / 2, mapboxMap.getHeight() / 2, TIME_MAP_NORTH_ANIMATION);
          }
          cameraChangeDispatcher.onCameraMoveStarted(MapboxMap.OnCameraMoveStartedListener.REASON_API_ANIMATION);
          compassView.isAnimating(true);
          compassView.postDelayed(compassView, TIME_WAIT_IDLE + TIME_MAP_NORTH_ANIMATION);
        }
      }
    };
  }

  //
  // Lifecycle events
  //

  /**
   * <p>
   * You must call this method from the parent's Activity#onCreate(Bundle)} or
   * Fragment#onCreate(Bundle).
   * </p>
   * You must set a valid access token with {@link com.mapbox.mapboxsdk.Mapbox#getInstance(Context, String)}
   * before you call this method or an exception will be thrown.
   *
   * @param savedInstanceState Pass in the parent's savedInstanceState.
   * @see com.mapbox.mapboxsdk.Mapbox#getInstance(Context, String)
   */
  @UiThread
  public void onCreate(@Nullable Bundle savedInstanceState) {
    if (savedInstanceState == null) {
      MapboxTelemetry.getInstance().pushEvent(MapboxEventWrapper.buildMapLoadEvent());
    } else if (savedInstanceState.getBoolean(MapboxConstants.STATE_HAS_SAVED_STATE)) {
      this.savedInstanceState = savedInstanceState;
    }
  }

  private void initialiseDrawingSurface() {
    glSurfaceView = (GLSurfaceView) findViewById(R.id.surfaceView);
    glSurfaceView.setZOrderMediaOverlay(mapboxMapOptions.getRenderSurfaceOnTop());
    glSurfaceView.setEGLContextClientVersion(2);
    glSurfaceView.setEGLConfigChooser(new EGLConfigChooser());

    MapRenderer mapRenderer = new MapRenderer(getContext(), glSurfaceView) {
      @Override
      public void onSurfaceCreated(GL10 gl, EGLConfig config) {
        MapView.this.post(new Runnable() {
          @Override
          public void run() {
            // Initialise only once
            if (mapboxMap == null) {
              initialiseMap();
              mapboxMap.onStart();
            }
          }
        });

        super.onSurfaceCreated(gl, config);
      }
    };

    glSurfaceView.setRenderer(mapRenderer);
    glSurfaceView.setRenderMode(RENDERMODE_WHEN_DIRTY);
    glSurfaceView.setVisibility(View.VISIBLE);

    nativeMapView = new NativeMapView(this, mapRenderer);
    nativeMapView.resizeView(getMeasuredWidth(), getMeasuredHeight());
  }

  /**
   * You must call this method from the parent's Activity#onSaveInstanceState(Bundle)
   * or Fragment#onSaveInstanceState(Bundle).
   *
   * @param outState Pass in the parent's outState.
   */
  @UiThread
  public void onSaveInstanceState(@NonNull Bundle outState) {
    outState.putBoolean(MapboxConstants.STATE_HAS_SAVED_STATE, true);
    mapboxMap.onSaveInstanceState(outState);
  }

  /**
   * You must call this method from the parent's Activity#onStart() or Fragment#onStart()
   */
  @UiThread
  public void onStart() {
    ConnectivityReceiver.instance(getContext()).activate();
    if (mapboxMap != null) {
      mapboxMap.onStart();
    }
  }

  /**
   * You must call this method from the parent's Activity#onResume() or Fragment#onResume().
   */
  @UiThread
  public void onResume() {
    if (glSurfaceView != null) {
      glSurfaceView.onResume();
    }
  }

  /**
   * You must call this method from the parent's Activity#onPause() or Fragment#onPause().
   */
  @UiThread
  public void onPause() {
    if (glSurfaceView != null) {
      glSurfaceView.onPause();
    }
  }

  /**
   * You must call this method from the parent's Activity#onStop() or Fragment#onStop().
   */
  @UiThread
  public void onStop() {
    mapboxMap.onStop();
    ConnectivityReceiver.instance(getContext()).deactivate();
  }

  /**
   * You must call this method from the parent's Activity#onDestroy() or Fragment#onDestroy().
   */
  @UiThread
  public void onDestroy() {
    destroyed = true;
    mapCallback.clearOnMapReadyCallbacks();
    nativeMapView.destroy();
    nativeMapView = null;
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    if (!isMapInitialized()) {
      return super.onTouchEvent(event);
    }

    if (event.getAction() == MotionEvent.ACTION_DOWN) {
      mapZoomButtonController.setVisible(true);
    }
    return mapGestureDetector.onTouchEvent(event) || super.onTouchEvent(event);
  }

  @Override
  public boolean onKeyDown(int keyCode, KeyEvent event) {
    return mapKeyListener.onKeyDown(keyCode, event) || super.onKeyDown(keyCode, event);
  }

  @Override
  public boolean onKeyLongPress(int keyCode, KeyEvent event) {
    return mapKeyListener.onKeyLongPress(keyCode, event) || super.onKeyLongPress(keyCode, event);
  }

  @Override
  public boolean onKeyUp(int keyCode, KeyEvent event) {
    return mapKeyListener.onKeyUp(keyCode, event) || super.onKeyUp(keyCode, event);
  }

  @Override
  public boolean onTrackballEvent(MotionEvent event) {
    return mapKeyListener.onTrackballEvent(event) || super.onTrackballEvent(event);
  }

  @Override
  public boolean onGenericMotionEvent(MotionEvent event) {
    return mapGestureDetector.onGenericMotionEvent(event) || super.onGenericMotionEvent(event);
  }

  @Override
  public boolean onHoverEvent(MotionEvent event) {
    switch (event.getActionMasked()) {
      case MotionEvent.ACTION_HOVER_ENTER:
      case MotionEvent.ACTION_HOVER_MOVE:
        mapZoomButtonController.setVisible(true);
        return true;

      case MotionEvent.ACTION_HOVER_EXIT:
        mapZoomButtonController.setVisible(false);
        return true;

      default:
        // We are not interested in this event
        return false;
    }
  }

  /**
   * You must call this method from the parent's Activity#onLowMemory() or Fragment#onLowMemory().
   */
  @UiThread
  public void onLowMemory() {
    nativeMapView.onLowMemory();
  }

  /**
   * <p>
   * Loads a new map style from the specified URL.
   * </p>
   * {@code url} can take the following forms:
   * <ul>
   * <li>{@code Style.*}: load one of the bundled styles in {@link Style}.</li>
   * <li>{@code mapbox://styles/<user>/<style>}:
   * retrieves the style from a <a href="https://www.mapbox.com/account/">Mapbox account.</a>
   * {@code user} is your username. {@code style} is the ID of your custom
   * style created in <a href="https://www.mapbox.com/studio">Mapbox Studio</a>.</li>
   * <li>{@code http://...} or {@code https://...}:
   * retrieves the style over the Internet from any web server.</li>
   * <li>{@code asset://...}:
   * reads the style from the APK {@code assets/} directory.
   * This is used to load a style bundled with your app.</li>
   * <li>{@code null}: loads the default {@link Style#MAPBOX_STREETS} style.</li>
   * </ul>
   * <p>
   * This method is asynchronous and will return immediately before the style finishes loading.
   * If you wish to wait for the map to finish loading listen for the {@link MapView#DID_FINISH_LOADING_MAP} event.
   * </p>
   * If the style fails to load or an invalid style URL is set, the map view will become blank.
   * An error message will be logged in the Android logcat and {@link MapView#DID_FAIL_LOADING_MAP} event will be sent.
   *
   * @param url The URL of the map style
   * @see Style
   */
  public void setStyleUrl(@NonNull String url) {
    if (destroyed) {
      return;
    }
    if (!isMapInitialized()) {
      mapboxMapOptions.styleUrl(url);
      return;
    }
    nativeMapView.setStyleUrl(url);
  }

  //
  // Rendering
  //

  @Override
  protected void onSizeChanged(int width, int height, int oldw, int oldh) {
    if (destroyed) {
      return;
    }

    if (!isInEditMode() && isMapInitialized()) {
      nativeMapView.resizeView(width, height);
    }
  }

  //
  // View events
  //

  // Called when view is no longer connected
  @Override
  @CallSuper
  protected void onDetachedFromWindow() {
    super.onDetachedFromWindow();
    mapZoomButtonController.setVisible(false);
  }

  // Called when view is hidden and shown
  @Override
  protected void onVisibilityChanged(@NonNull View changedView, int visibility) {
    if (isInEditMode()) {
      return;
    }

    if (mapZoomButtonController != null) {
      mapZoomButtonController.setVisible(visibility == View.VISIBLE);
    }
  }

  //
  // Map events
  //

  void onMapChange(int rawChange) {
    for (MapView.OnMapChangedListener onMapChangedListener : onMapChangedListeners) {
      try {
        onMapChangedListener.onMapChanged(rawChange);
      } catch (RuntimeException err) {
        Timber.e(err, "Exception in MapView.OnMapChangedListener");
      }
    }
  }

  /**
   * <p>
   * Add a callback that's invoked when the displayed map view changes.
   * </p>
   * To remove the callback, use {@link MapView#removeOnMapChangedListener(OnMapChangedListener)}.
   *
   * @param listener The callback that's invoked on every frame rendered to the map view.
   * @see MapView#removeOnMapChangedListener(OnMapChangedListener)
   */
  public void addOnMapChangedListener(@Nullable OnMapChangedListener listener) {
    if (listener != null) {
      onMapChangedListeners.add(listener);
    }
  }

  /**
   * Remove a callback added with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}
   *
   * @param listener The previously added callback to remove.
   * @see MapView#addOnMapChangedListener(OnMapChangedListener)
   */
  public void removeOnMapChangedListener(@Nullable OnMapChangedListener listener) {
    if (listener != null) {
      onMapChangedListeners.remove(listener);
    }
  }

  /**
   * Sets a callback object which will be triggered when the {@link MapboxMap} instance is ready to be used.
   *
   * @param callback The callback object that will be triggered when the map is ready to be used.
   */
  @UiThread
  public void getMapAsync(final OnMapReadyCallback callback) {
    if (!mapCallback.isInitialLoad() && callback != null) {
      callback.onMapReady(mapboxMap);
    } else {
      if (callback != null) {
        mapCallback.addOnMapReadyCallback(callback);
      }
    }
  }

  private boolean isMapInitialized() {
    return nativeMapView != null;
  }

  MapboxMap getMapboxMap() {
    return mapboxMap;
  }

  void setMapboxMap(MapboxMap mapboxMap) {
    this.mapboxMap = mapboxMap;
  }

  /**
   * Definition of a map change event.
   *
   * @see MapView.OnMapChangedListener#onMapChanged(int)
   */
  @IntDef( {REGION_WILL_CHANGE,
    REGION_WILL_CHANGE_ANIMATED,
    REGION_IS_CHANGING,
    REGION_DID_CHANGE,
    REGION_DID_CHANGE_ANIMATED,
    WILL_START_LOADING_MAP,
    DID_FINISH_LOADING_MAP,
    DID_FAIL_LOADING_MAP,
    WILL_START_RENDERING_FRAME,
    DID_FINISH_RENDERING_FRAME,
    DID_FINISH_RENDERING_FRAME_FULLY_RENDERED,
    WILL_START_RENDERING_MAP,
    DID_FINISH_RENDERING_MAP,
    DID_FINISH_RENDERING_MAP_FULLY_RENDERED,
    DID_FINISH_LOADING_STYLE,
    SOURCE_DID_CHANGE
  })
  @Retention(RetentionPolicy.SOURCE)
  public @interface MapChange {
  }

  /**
   * This event is triggered whenever the currently displayed map region is about to changing
   * without an animation.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int REGION_WILL_CHANGE = 0;

  /**
   * This event is triggered whenever the currently displayed map region is about to changing
   * with an animation.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int REGION_WILL_CHANGE_ANIMATED = 1;

  /**
   * This event is triggered whenever the currently displayed map region is changing.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int REGION_IS_CHANGING = 2;

  /**
   * This event is triggered whenever the currently displayed map region finished changing
   * without an animation.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int REGION_DID_CHANGE = 3;

  /**
   * This event is triggered whenever the currently displayed map region finished changing
   * with an animation.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int REGION_DID_CHANGE_ANIMATED = 4;

  /**
   * This event is triggered when the map is about to start loading a new map style.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int WILL_START_LOADING_MAP = 5;

  /**
   * This  is triggered when the map has successfully loaded a new map style.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_LOADING_MAP = 6;

  /**
   * This event is triggered when the map has failed to load a new map style.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FAIL_LOADING_MAP = 7;

  /**
   * This event is triggered when the map will start rendering a frame.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int WILL_START_RENDERING_FRAME = 8;

  /**
   * This event is triggered when the map finished rendering a frame.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_RENDERING_FRAME = 9;

  /**
   * This event is triggered when the map finished rendering the frame fully.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_RENDERING_FRAME_FULLY_RENDERED = 10;

  /**
   * This event is triggered when the map will start rendering the map.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int WILL_START_RENDERING_MAP = 11;

  /**
   * This event is triggered when the map finished rendering the map.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_RENDERING_MAP = 12;

  /**
   * This event is triggered when the map is fully rendered.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_RENDERING_MAP_FULLY_RENDERED = 13;

  /**
   * This {@link MapChange} is triggered when a style has finished loading.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int DID_FINISH_LOADING_STYLE = 14;

  /**
   * This {@link MapChange} is triggered when a source changes.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapChange
   * @see MapView.OnMapChangedListener
   */
  public static final int SOURCE_DID_CHANGE = 15;

  /**
   * Interface definition for a callback to be invoked when the displayed map view changes.
   * <p>
   * Register to {@link MapChange} events with {@link MapView#addOnMapChangedListener(OnMapChangedListener)}.
   * </p>
   *
   * @see MapView#addOnMapChangedListener(OnMapChangedListener)
   * @see MapView.MapChange
   */
  public interface OnMapChangedListener {
    /**
     * Called when the displayed map view changes.
     *
     * @param change Type of map change event, one of {@link #REGION_WILL_CHANGE},
     *               {@link #REGION_WILL_CHANGE_ANIMATED},
     *               {@link #REGION_IS_CHANGING},
     *               {@link #REGION_DID_CHANGE},
     *               {@link #REGION_DID_CHANGE_ANIMATED},
     *               {@link #WILL_START_LOADING_MAP},
     *               {@link #DID_FAIL_LOADING_MAP},
     *               {@link #DID_FINISH_LOADING_MAP},
     *               {@link #WILL_START_RENDERING_FRAME},
     *               {@link #DID_FINISH_RENDERING_FRAME},
     *               {@link #DID_FINISH_RENDERING_FRAME_FULLY_RENDERED},
     *               {@link #WILL_START_RENDERING_MAP},
     *               {@link #DID_FINISH_RENDERING_MAP},
     *               {@link #DID_FINISH_RENDERING_MAP_FULLY_RENDERED}.
     */
    void onMapChanged(@MapChange int change);
  }

  private class FocalPointInvalidator implements FocalPointChangeListener {

    private final List<FocalPointChangeListener> focalPointChangeListeners = new ArrayList<>();

    void addListener(FocalPointChangeListener focalPointChangeListener) {
      focalPointChangeListeners.add(focalPointChangeListener);
    }

    @Override
    public void onFocalPointChanged(PointF pointF) {
      mapGestureDetector.setFocalPoint(pointF);
      for (FocalPointChangeListener focalPointChangeListener : focalPointChangeListeners) {
        focalPointChangeListener.onFocalPointChanged(pointF);
      }
    }
  }

  private class RegisterTouchListener implements MapboxMap.OnRegisterTouchListener {

    @Override
    public void onRegisterMapClickListener(MapboxMap.OnMapClickListener listener) {
      mapGestureDetector.setOnMapClickListener(listener);
    }

    @Override
    public void onRegisterMapLongClickListener(MapboxMap.OnMapLongClickListener listener) {
      mapGestureDetector.setOnMapLongClickListener(listener);
    }

    @Override
    public void onRegisterScrollListener(MapboxMap.OnScrollListener listener) {
      mapGestureDetector.setOnScrollListener(listener);
    }

    @Override
    public void onRegisterFlingListener(MapboxMap.OnFlingListener listener) {
      mapGestureDetector.setOnFlingListener(listener);
    }
  }

  private class MapZoomControllerListener implements ZoomButtonsController.OnZoomListener {

    private final MapGestureDetector mapGestureDetector;
    private final UiSettings uiSettings;
    private final Transform transform;

    MapZoomControllerListener(MapGestureDetector detector, UiSettings uiSettings, Transform transform) {
      this.mapGestureDetector = detector;
      this.uiSettings = uiSettings;
      this.transform = transform;
    }

    // Not used
    @Override
    public void onVisibilityChanged(boolean visible) {
      // Ignore
    }

    // Called when user pushes a zoom button on the ZoomButtonController
    @Override
    public void onZoom(boolean zoomIn) {
      if (uiSettings.isZoomGesturesEnabled()) {
        onZoom(zoomIn, mapGestureDetector.getFocalPoint());
      }
    }

    private void onZoom(boolean zoomIn, @Nullable PointF focalPoint) {
      if (focalPoint != null) {
        transform.zoom(zoomIn, focalPoint);
      } else {
        PointF centerPoint = new PointF(getMeasuredWidth() / 2, getMeasuredHeight() / 2);
        transform.zoom(zoomIn, centerPoint);
      }
    }
  }

  private class CameraZoomInvalidator implements TrackingSettings.CameraZoomInvalidator {

    @Override
    public void zoomTo(double zoomLevel) {
      Transform transform = mapboxMap.getTransform();
      double currentZoomLevel = transform.getCameraPosition().zoom;
      if (currentZoomLevel < zoomLevel) {
        setZoom(zoomLevel, mapGestureDetector.getFocalPoint(), transform);
      }
    }

    private void setZoom(double zoomLevel, @Nullable PointF focalPoint, @NonNull Transform transform) {
      if (focalPoint != null) {
        transform.setZoom(zoomLevel, focalPoint);
      } else {
        PointF centerPoint = new PointF(getMeasuredWidth() / 2, getMeasuredHeight() / 2);
        transform.setZoom(zoomLevel, centerPoint);
      }
    }
  }

  private static class MapCallback implements OnMapChangedListener {

    private MapboxMap mapboxMap;
    private final List<OnMapReadyCallback> onMapReadyCallbackList = new ArrayList<>();
    private boolean initialLoad = true;

    void attachMapboxMap(MapboxMap mapboxMap) {
      this.mapboxMap = mapboxMap;
    }

    @Override
    public void onMapChanged(@MapChange int change) {
      if (change == DID_FINISH_LOADING_STYLE && initialLoad) {
        initialLoad = false;
        mapboxMap.onPreMapReady();
        onMapReady();
        mapboxMap.onPostMapReady();
      } else if (change == DID_FINISH_RENDERING_FRAME || change == DID_FINISH_RENDERING_FRAME_FULLY_RENDERED) {
        mapboxMap.onUpdateFullyRendered();
      } else if (change == REGION_IS_CHANGING || change == REGION_DID_CHANGE || change == DID_FINISH_LOADING_MAP) {
        mapboxMap.onUpdateRegionChange();
      }
    }

    private void onMapReady() {
      if (onMapReadyCallbackList.size() > 0) {
        // Notify listeners, clear when done
        Iterator<OnMapReadyCallback> iterator = onMapReadyCallbackList.iterator();
        while (iterator.hasNext()) {
          OnMapReadyCallback callback = iterator.next();
          callback.onMapReady(mapboxMap);
          iterator.remove();
        }
      }
    }

    boolean isInitialLoad() {
      return initialLoad;
    }

    void addOnMapReadyCallback(OnMapReadyCallback callback) {
      onMapReadyCallbackList.add(callback);
    }

    void clearOnMapReadyCallbacks() {
      onMapReadyCallbackList.clear();
    }
  }
}