src/com/android/car/hvac/controllers/HvacPanelController.java - platform/packages/apps/Car/Hvac - Git at Google

 /*
  * 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.car.hvac.controllers;

 import android.animation.Animator;
 import android.animation.AnimatorSet;
 import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Handler;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.WindowManager;
 import android.widget.ImageView;

 import androidx.annotation.IntDef;

 import com.android.car.hvac.HvacController;
 import com.android.car.hvac.R;
 import com.android.car.hvac.ui.FanDirectionButtons;
 import com.android.car.hvac.ui.FanSpeedBar;
 import com.android.car.hvac.ui.HvacPanelRow;
 import com.android.car.hvac.ui.SeatWarmerButton;
 import com.android.car.hvac.ui.TemperatureBarOverlay;
 import com.android.car.hvac.ui.ToggleButton;

 import java.util.ArrayList;
 import java.util.List;

 /**
  * A state machine to control transition from various HVAC UI layouts.
  */
 public class HvacPanelController {
     private static final int PANEL_ANIMATION_TIME_MS = 200;
     private static final int PANEL_COLLAPSE_ANIMATION_TIME_MS = 500;

     private static final int PANEL_ANIMATION_DELAY_MS = 100;
     private static final int PANEL_ANIMATION_LONG_DELAY_MS = 3 * PANEL_ANIMATION_DELAY_MS;

     private static final float DISABLED_BUTTON_ALPHA = 0.20f;
     private static final float ENABLED_BUTTON_ALPHA = 1.0f;

     private static final int STATE_COLLAPSED = 0;
     private static final int STATE_COLLAPSED_DIMMED = 1;
     private static final int STATE_FULL_EXPANDED = 2;
     // Allows for delayed invocation of code. Thus we can control UI events to happen after
     // others. Example: set something visible but do it after we've complete current UI updates.
     private static Handler handler = new Handler();

     // We have both a collapsed and expanded version of the overlays due to a bug
     // that does not correctly rendering a window resize event. Thus we toggle the the visibility
     // of the windows instead. A better solution would be a having separate views collapsed state
     // since the it does not need the other elements but this works for now.
     private TemperatureBarOverlay mDriverTemperatureBarCollapsed;
     private TemperatureBarOverlay mPassengerTemperatureBarCollapsed;
     private TemperatureBarOverlay mDriverTemperatureBarExpanded;
     private TemperatureBarOverlay mPassengerTemperatureBarExpanded;
     private final boolean mShowCollapsed;

     @IntDef({STATE_COLLAPSED,
             STATE_COLLAPSED_DIMMED,
             STATE_FULL_EXPANDED})
     private @interface HvacPanelState {}

     private @HvacPanelState int mCurrentState;

     private int mPanelCollapsedHeight;
     private int mPanelFullExpandedHeight;

     private View mPanel;
     private View mContainer;

     private SeatWarmerButton mDriverSeatWarmer;
     private SeatWarmerButton mPassengerSeatWarmer;

     private ToggleButton mHvacPowerSwitch;

     private ToggleButton mAcButton;
     private ToggleButton mRecycleAirButton;

     private ToggleButton mFrontDefrosterButton;
     private ToggleButton mRearDefrosterButton;

     private Drawable mAutoOnDrawable;
     private Drawable mAutoOffDrawable;

     private ImageView mAutoButton;

     private HvacPanelRow mPanelTopRow;
     private HvacPanelRow mPanelBottomRow;

     private FanSpeedBar mFanSpeedBar;
     private FanDirectionButtons mFanDirectionButtons;

     private float mTopPanelMaxAlpha = 1.0f;

     private WindowManager mWindowManager;

     private HvacPanelStateTransition mTransition;

     private View mHvacFanControlBackground;

     private HvacController mHvacController;
     private FanSpeedBarController mFanSpeedBarController;
     private FanDirectionButtonsController mFanDirectionButtonsController;
     private TemperatureController mTemperatureController;
     private TemperatureController mTemperatureControllerCollapsed;
     private SeatWarmerController mSeatWarmerController;

     private boolean mInAnimation;

     // TODO: read from shared pref
     private boolean mAutoMode;

     public HvacPanelController(Context context, View container,
             WindowManager windowManager,
             TemperatureBarOverlay driverTemperatureExpanded,
             TemperatureBarOverlay passengerTemperatureExpanded,
             TemperatureBarOverlay driverTemperatureBarCollapsed,
             TemperatureBarOverlay passengerTemperatureBarCollapsed) {
         Resources res = context.getResources();
         mShowCollapsed = res.getBoolean(R.bool.config_showCollapsedBars);

         mDriverTemperatureBarCollapsed = driverTemperatureBarCollapsed;
         mPassengerTemperatureBarCollapsed = passengerTemperatureBarCollapsed;

         mCurrentState = STATE_COLLAPSED;
         mWindowManager = windowManager;

         mPanelCollapsedHeight = res.getDimensionPixelSize(R.dimen.car_hvac_panel_collapsed_height);
         mPanelFullExpandedHeight
                 = res.getDimensionPixelSize(R.dimen.car_hvac_panel_full_expanded_height);

         mAutoOffDrawable = res.getDrawable(R.drawable.ic_auto_off);
         mAutoOnDrawable = res.getDrawable(R.drawable.ic_auto_on);

         mDriverTemperatureBarExpanded = driverTemperatureExpanded;
         mPassengerTemperatureBarExpanded = passengerTemperatureExpanded;

         mDriverTemperatureBarExpanded.setCloseButtonOnClickListener(mCollapseHvac);
         mPassengerTemperatureBarExpanded.setCloseButtonOnClickListener(mCollapseHvac);

         // Initially the hvac panel is collapsed, hide the expanded version.
         mDriverTemperatureBarExpanded.setVisibility(View.INVISIBLE);
         mPassengerTemperatureBarExpanded.setVisibility(View.INVISIBLE);

         mPassengerTemperatureBarCollapsed.setBarOnClickListener(mExpandHvac);
         mDriverTemperatureBarCollapsed.setBarOnClickListener(mExpandHvac);

         mContainer = container;
         mContainer.setVisibility(View.INVISIBLE);
         mContainer.setOnClickListener(mCollapseHvac);
         mPanel = mContainer.findViewById(R.id.hvac_center_panel);

         mHvacFanControlBackground = mPanel.findViewById(R.id.fan_control_bg);
         // set clickable so that clicks are not forward to the mContainer. This way a miss click
         // does not close the UI
         mPanel.setClickable(true);

         // Set up top row buttons
         mPanelTopRow = (HvacPanelRow) mContainer.findViewById(R.id.top_row);

         mAcButton = (ToggleButton) mPanelTopRow.findViewById(R.id.ac_button);
         mAcButton.setToggleIcons(res.getDrawable(R.drawable.ic_ac_on),
                 res.getDrawable(R.drawable.ic_ac_off));

         mRecycleAirButton = (ToggleButton) mPanelTopRow.findViewById(R.id.recycle_air_button);

         mRecycleAirButton.setToggleIcons(res.getDrawable(R.drawable.ic_recycle_air_on),
                 res.getDrawable(R.drawable.ic_recycle_air_off));

         // Setup bottom row buttons
         mPanelBottomRow = (HvacPanelRow) mContainer.findViewById(R.id.bottom_row);

         mAutoButton = (ImageView) mContainer.findViewById(R.id.auto_button);
         mAutoButton.setOnClickListener(mAutoButtonClickListener);

         mFrontDefrosterButton = (ToggleButton) mPanelBottomRow.findViewById(R.id.front_defroster);
         mRearDefrosterButton = (ToggleButton) mPanelBottomRow.findViewById(R.id.rear_defroster);

         mFrontDefrosterButton.setToggleIcons(res.getDrawable(R.drawable.ic_front_defroster_on),
                 res.getDrawable(R.drawable.ic_front_defroster_off));

         mRearDefrosterButton.setToggleIcons(res.getDrawable(R.drawable.ic_rear_defroster_on),
                 res.getDrawable(R.drawable.ic_rear_defroster_off));

         mFanSpeedBar = (FanSpeedBar) mContainer.findViewById(R.id.fan_speed_bar);
         mFanDirectionButtons = (FanDirectionButtons) mContainer.findViewById(R.id.fan_direction_buttons);

         mDriverSeatWarmer = (SeatWarmerButton) mContainer.findViewById(R.id.left_seat_heater);
         mPassengerSeatWarmer = (SeatWarmerButton) mContainer.findViewById(R.id.right_seat_heater);

         mHvacPowerSwitch = (ToggleButton)mPanelBottomRow.findViewById(R.id.hvac_master_switch);
         // TODO: this is not good UX design - just a placeholder
         mHvacPowerSwitch.setToggleIcons(res.getDrawable(R.drawable.ac_master_switch_on),
             res.getDrawable(R.drawable.ac_master_switch_off));

         if (!mShowCollapsed) {
             mDriverTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
             mPassengerTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
         }
     }

     public void updateHvacController(HvacController controller) {
         //TODO: handle disconnected HvacController.
         mHvacController = controller;

         mFanSpeedBarController = new FanSpeedBarController(mFanSpeedBar, mHvacController);
         mFanDirectionButtonsController
                 = new FanDirectionButtonsController(mFanDirectionButtons, mHvacController);
         mTemperatureController = new TemperatureController(
                 mPassengerTemperatureBarExpanded,
                 mDriverTemperatureBarExpanded,
                 mPassengerTemperatureBarCollapsed,
                 mDriverTemperatureBarCollapsed,
                 mHvacController);
         mSeatWarmerController = new SeatWarmerController(mPassengerSeatWarmer,
                 mDriverSeatWarmer, mHvacController);

         // Toggle buttons do not need additional logic to map between hardware
         // and UI settings. Simply use a ToggleListener to handle clicks.
         mAcButton.setIsOn(mHvacController.getAcState());
         mAcButton.setToggleListener(new ToggleButton.ToggleListener() {
             @Override
             public void onToggled(boolean isOn) {
                 mHvacController.setAcState(isOn);
             }
         });

         mFrontDefrosterButton.setIsOn(mHvacController.getFrontDefrosterState());
         mFrontDefrosterButton.setToggleListener(new ToggleButton.ToggleListener() {
             @Override
             public void onToggled(boolean isOn) {
                 mHvacController.setFrontDefrosterState(isOn);
             }
         });

         mRearDefrosterButton.setIsOn(mHvacController.getRearDefrosterState());
         mRearDefrosterButton.setToggleListener(new ToggleButton.ToggleListener() {
             @Override
             public void onToggled(boolean isOn) {
                 mHvacController.setRearDefrosterState(isOn);
             }
         });

         mRecycleAirButton.setIsOn(mHvacController.getAirCirculationState());
         mRecycleAirButton.setToggleListener(new ToggleButton.ToggleListener() {
             @Override
             public void onToggled(boolean isOn) {
                 mHvacController.setAirCirculation(isOn);
             }
         });

         setAutoMode(mHvacController.getAutoModeState());

         mHvacPowerSwitch.setIsOn(mHvacController.getHvacPowerState());
         mHvacPowerSwitch.setToggleListener(isOn -> mHvacController.setHvacPowerState(isOn));

         mHvacController.registerCallback(mToggleButtonCallbacks);
         mToggleButtonCallbacks.onHvacPowerChange(mHvacController.getHvacPowerState());
     }

     private HvacController.Callback mToggleButtonCallbacks
             = new HvacController.Callback() {
         @Override
         public void onAirCirculationChange(boolean isOn) {
             mRecycleAirButton.setIsOn(isOn);
         }

         @Override
         public void onFrontDefrosterChange(boolean isOn) {
             mFrontDefrosterButton.setIsOn(isOn);
         }

         @Override
         public void onRearDefrosterChange(boolean isOn) {
             mRearDefrosterButton.setIsOn(isOn);
         }

         @Override
         public void onAcStateChange(boolean isOn) {
             mAcButton.setIsOn(isOn);
         }

         @Override
         public void onAutoModeChange(boolean isOn) {
             mAutoMode = isOn;
             setAutoMode(mAutoMode);
         }
     };

     /**
      * Take the listeners and animators from a {@link AnimatorSet} and merge them to the
      * input {@link Animator} and {@link android.animation.Animator.AnimatorListener} lists.
      */
     private void combineAnimationSet(List<Animator> animatorList,
             List<Animator.AnimatorListener> listenerList, AnimatorSet set) {

         ArrayList<Animator> list = set.getChildAnimations();
         if (list != null) {
             int size = list.size();
             for (int i = 0; i < size; i++) {
                 animatorList.add(list.get(i));
             }
         }

         ArrayList<Animator.AnimatorListener> listeners = set.getListeners();
         if (listeners != null) {
             int size = listeners.size();
             for (int i = 0; i < size; i++) {
                 listenerList.add(listeners.get(i));
             }
         }
     }

     /**
      * Play necessary animations between {@link HvacPanelState} transitions
      */
     private void transitionState(@HvacPanelState int startState, @HvacPanelState int endState) {
         if (startState == endState || mInAnimation) {
             return;
         }

         List<Animator> animationList = new ArrayList<>();
         List<Animator.AnimatorListener> listenerList = new ArrayList<>();
         ValueAnimator heightAnimator = getPanelHeightAnimator(startState, endState);
         mTransition = new HvacPanelStateTransition(startState, endState);
         ValueAnimator fanBgAlphaAnimator;
         switch (endState) {
             case STATE_COLLAPSED:
                 // Transition to collapsed state:
                 // 1. Collapse the temperature bars.
                 // 2. Collapse the top and bottom panel, staggered with a different delay.
                 // 3. Decrease height of the hvac center panel, but maintain container height.
                 // 4. Fade the background of the fan controls seperately to create staggered effect.
                 animationList.add(heightAnimator);
                 heightAnimator.setDuration(PANEL_COLLAPSE_ANIMATION_TIME_MS);
                 fanBgAlphaAnimator
                         = ObjectAnimator.ofFloat(mHvacFanControlBackground, View.ALPHA, 1, 0)
                         .setDuration(PANEL_COLLAPSE_ANIMATION_TIME_MS);
                 fanBgAlphaAnimator.setStartDelay(PANEL_ANIMATION_DELAY_MS);
                 animationList.add(fanBgAlphaAnimator);

                 ValueAnimator panelAlphaAnimator
                         = ObjectAnimator.ofFloat(mContainer, View.ALPHA, 1, 0);
                 panelAlphaAnimator.setDuration(200);
                 panelAlphaAnimator.setStartDelay(300);

                 animationList.add(panelAlphaAnimator);

                 combineAnimationSet(animationList, listenerList,
                         mDriverTemperatureBarExpanded.getCollapseAnimations());
                 combineAnimationSet(animationList, listenerList,
                         mPassengerTemperatureBarExpanded.getCollapseAnimations());

                 combineAnimationSet(animationList, listenerList,
                         mPanelTopRow.getCollapseAnimation(PANEL_ANIMATION_DELAY_MS,
                                 mTopPanelMaxAlpha));
                 combineAnimationSet(animationList, listenerList,
                         mPanelBottomRow.getCollapseAnimation(PANEL_ANIMATION_DELAY_MS,
                                 mTopPanelMaxAlpha));
                 break;
             case STATE_COLLAPSED_DIMMED:
                 // Hide the temperature numbers, open arrows and auto state button.
                 // TODO: determine if this section is still needed.
                 break;
             case STATE_FULL_EXPANDED:
                 // Transition to expaneded state:
                 // 1. Expand the temperature bars.
                 // 2. Expand the top and bottom panel, staggered with a different delay.
                 // 3. Increase height of the hvac center panel, but maintain container height.
                 // 4. Fade in fan control background in a staggered manner.
                 fanBgAlphaAnimator
                         = ObjectAnimator.ofFloat(mHvacFanControlBackground, View.ALPHA, 0, 1)
                         .setDuration(PANEL_ANIMATION_TIME_MS);
                 fanBgAlphaAnimator.setStartDelay(PANEL_ANIMATION_DELAY_MS);
                 animationList.add(fanBgAlphaAnimator);

                 animationList.add(heightAnimator);
                 combineAnimationSet(animationList, listenerList,
                         mDriverTemperatureBarExpanded.getExpandAnimatons());
                 combineAnimationSet(animationList, listenerList,
                         mPassengerTemperatureBarExpanded.getExpandAnimatons());

                 // During expansion, the bottom panel animation should be delayed
                 combineAnimationSet(animationList, listenerList,
                         mPanelTopRow.getExpandAnimation(PANEL_ANIMATION_DELAY_MS,
                                 mTopPanelMaxAlpha));
                 combineAnimationSet(animationList, listenerList,
                         mPanelBottomRow.getExpandAnimation(PANEL_ANIMATION_LONG_DELAY_MS, 1f));
                 break;
             default:
         }

         // If there are animations for the state change, play them all together and ensure
         // the animation listeners are attached.
         if (animationList.size() > 0) {
             AnimatorSet animatorSet = new AnimatorSet();
             animatorSet.playTogether(animationList);
             for (Animator.AnimatorListener listener : listenerList) {
                 animatorSet.addListener(listener);
             }
             animatorSet.addListener(mAnimatorListener);
             animatorSet.start();
         }
     }

     private AnimatorSet.AnimatorListener mAnimatorListener = new AnimatorSet.AnimatorListener() {
         @Override
         public void onAnimationStart(Animator animation) {
             mTransition.onTransitionStart();
         }

         @Override
         public void onAnimationEnd(Animator animation) {
             mTransition.onTransitionComplete();
         }

         @Override
         public void onAnimationCancel(Animator animation) {}

         @Override
         public void onAnimationRepeat(Animator animation) {}
     };

     private ValueAnimator getPanelHeightAnimator(@HvacPanelState int startState,
             @HvacPanelState int endState) {
         int startHeight = getStateHeight(startState);
         int endHeight = getStateHeight(endState);
         if (startHeight == endHeight) {
             return null;
         }

         ValueAnimator heightAnimator = new ValueAnimator().ofInt(startHeight, endHeight)
                 .setDuration(PANEL_ANIMATION_TIME_MS);
         heightAnimator.addUpdateListener(mHeightUpdateListener);
         return heightAnimator;
     }

     private int getStateHeight(@HvacPanelState int state) {
         switch (state) {
             case STATE_COLLAPSED:
             case STATE_COLLAPSED_DIMMED:
                 return mPanelCollapsedHeight;
             case STATE_FULL_EXPANDED:
                 return mPanelFullExpandedHeight;
             default:
                 throw new IllegalArgumentException("No height mapped to HVAC State: " + state);
         }
     }

     private void setAutoMode(boolean isOn) {
         if (isOn) {
             mPanelTopRow.setOnTouchListener(new View.OnTouchListener() {
                 @Override
                 public boolean onTouch(View v, MotionEvent event) {
                     return true;
                 }
             });
             mAutoMode = true;
             mPanelTopRow.disablePanel(true);
             mTopPanelMaxAlpha = DISABLED_BUTTON_ALPHA;
             mAutoButton.setImageDrawable(mAutoOnDrawable);
         } else {
             mPanelTopRow.disablePanel(false);
             mTopPanelMaxAlpha = ENABLED_BUTTON_ALPHA;
             mAutoButton.setImageDrawable(mAutoOffDrawable);
         }
         mHvacFanControlBackground.setAlpha(mTopPanelMaxAlpha);
         mPanelTopRow.setAlpha(mTopPanelMaxAlpha);
     }

     private View.OnClickListener mAutoButtonClickListener = new View.OnClickListener() {
         @Override
         public void onClick(View v) {
             if (mAutoMode) {
                 mAutoMode = false;
             } else {
                 mAutoMode = true;
             }
             mHvacController.setAutoMode(mAutoMode);
             setAutoMode(mAutoMode);
         }
     };

      private View.OnClickListener mCollapseHvac = new View.OnClickListener() {
          @Override
          public void onClick(View v) {
              if (mInAnimation) {
                  return;
              }
              if (mCurrentState != STATE_COLLAPSED) {
                  transitionState(mCurrentState, STATE_COLLAPSED);
              }
          }
      };

     public void toggleHvacUi() {
         if(mCurrentState != STATE_COLLAPSED) {
             mCollapseHvac.onClick(null);
         } else {
             mExpandHvac.onClick(null);
         }
     }

     public View.OnClickListener mExpandHvac = new View.OnClickListener() {
         @Override
         public void onClick(View v) {
              if (mInAnimation) {
                 return;
             }
             if (mCurrentState != STATE_FULL_EXPANDED) {
                 transitionState(mCurrentState, STATE_FULL_EXPANDED);
             }
         }
     };


     private ValueAnimator.AnimatorUpdateListener mHeightUpdateListener
             = new ValueAnimator.AnimatorUpdateListener() {
         @Override
         public void onAnimationUpdate(ValueAnimator animation) {
             int height = (Integer) animation.getAnimatedValue();
             int currentHeight = mPanel.getLayoutParams().height;
             mPanel.getLayoutParams().height = height;
             mPanel.setTop(mPanel.getTop() + height - currentHeight);
             mPanel.requestLayout();
         }
     };

     /**
      * Handles the necessary setup/clean up before and after a state transition.
      */
     private class HvacPanelStateTransition {
         private @HvacPanelState int mEndState;
         private @HvacPanelState int mStartState;

         public HvacPanelStateTransition(@HvacPanelState int startState,
                 @HvacPanelState int endState) {
             mStartState = startState;
             mEndState = endState;
         }

         public void onTransitionStart() {
             mInAnimation = true;
             if (mEndState == STATE_FULL_EXPANDED) {
                 mPassengerTemperatureBarExpanded.setVisibility(View.VISIBLE);
                 mDriverTemperatureBarExpanded.setVisibility(View.VISIBLE);
                 if (mShowCollapsed) {
                     mDriverTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
                     mPassengerTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
                 }
                 mContainer.setAlpha(1);
                 mContainer.setVisibility(View.VISIBLE);
             }
         }

         public void onTransitionComplete() {
             if (mEndState == STATE_COLLAPSED) {
                 if (mShowCollapsed) {
                     mDriverTemperatureBarCollapsed.setVisibility(View.VISIBLE);
                     mPassengerTemperatureBarCollapsed.setVisibility(View.VISIBLE);
                 }
                 handler.postAtFrontOfQueue(() -> {
                     mDriverTemperatureBarExpanded.setVisibility(View.INVISIBLE);
                     mPassengerTemperatureBarExpanded.setVisibility(View.INVISIBLE);
                 });
             }
             if (mStartState == STATE_FULL_EXPANDED) {
                 mContainer.setVisibility(View.INVISIBLE);
             }

             // set new states
             mCurrentState = mEndState;
             mInAnimation = false;
         }
     }
 }
	/*
	* 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.car.hvac.controllers;

	import android.animation.Animator;
	import android.animation.AnimatorSet;
	import android.animation.ObjectAnimator;
	import android.animation.ValueAnimator;
	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.drawable.Drawable;
	import android.os.Handler;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.WindowManager;
	import android.widget.ImageView;

	import androidx.annotation.IntDef;

	import com.android.car.hvac.HvacController;
	import com.android.car.hvac.R;
	import com.android.car.hvac.ui.FanDirectionButtons;
	import com.android.car.hvac.ui.FanSpeedBar;
	import com.android.car.hvac.ui.HvacPanelRow;
	import com.android.car.hvac.ui.SeatWarmerButton;
	import com.android.car.hvac.ui.TemperatureBarOverlay;
	import com.android.car.hvac.ui.ToggleButton;

	import java.util.ArrayList;
	import java.util.List;

	/**
	* A state machine to control transition from various HVAC UI layouts.
	*/
	public class HvacPanelController {
	private static final int PANEL_ANIMATION_TIME_MS = 200;
	private static final int PANEL_COLLAPSE_ANIMATION_TIME_MS = 500;

	private static final int PANEL_ANIMATION_DELAY_MS = 100;
	private static final int PANEL_ANIMATION_LONG_DELAY_MS = 3 * PANEL_ANIMATION_DELAY_MS;

	private static final float DISABLED_BUTTON_ALPHA = 0.20f;
	private static final float ENABLED_BUTTON_ALPHA = 1.0f;

	private static final int STATE_COLLAPSED = 0;
	private static final int STATE_COLLAPSED_DIMMED = 1;
	private static final int STATE_FULL_EXPANDED = 2;
	// Allows for delayed invocation of code. Thus we can control UI events to happen after
	// others. Example: set something visible but do it after we've complete current UI updates.
	private static Handler handler = new Handler();

	// We have both a collapsed and expanded version of the overlays due to a bug
	// that does not correctly rendering a window resize event. Thus we toggle the the visibility
	// of the windows instead. A better solution would be a having separate views collapsed state
	// since the it does not need the other elements but this works for now.
	private TemperatureBarOverlay mDriverTemperatureBarCollapsed;
	private TemperatureBarOverlay mPassengerTemperatureBarCollapsed;
	private TemperatureBarOverlay mDriverTemperatureBarExpanded;
	private TemperatureBarOverlay mPassengerTemperatureBarExpanded;
	private final boolean mShowCollapsed;

	@IntDef({STATE_COLLAPSED,
	STATE_COLLAPSED_DIMMED,
	STATE_FULL_EXPANDED})
	private @interface HvacPanelState {}

	private @HvacPanelState int mCurrentState;

	private int mPanelCollapsedHeight;
	private int mPanelFullExpandedHeight;

	private View mPanel;
	private View mContainer;

	private SeatWarmerButton mDriverSeatWarmer;
	private SeatWarmerButton mPassengerSeatWarmer;

	private ToggleButton mHvacPowerSwitch;

	private ToggleButton mAcButton;
	private ToggleButton mRecycleAirButton;

	private ToggleButton mFrontDefrosterButton;
	private ToggleButton mRearDefrosterButton;

	private Drawable mAutoOnDrawable;
	private Drawable mAutoOffDrawable;

	private ImageView mAutoButton;

	private HvacPanelRow mPanelTopRow;
	private HvacPanelRow mPanelBottomRow;

	private FanSpeedBar mFanSpeedBar;
	private FanDirectionButtons mFanDirectionButtons;

	private float mTopPanelMaxAlpha = 1.0f;

	private WindowManager mWindowManager;

	private HvacPanelStateTransition mTransition;

	private View mHvacFanControlBackground;

	private HvacController mHvacController;
	private FanSpeedBarController mFanSpeedBarController;
	private FanDirectionButtonsController mFanDirectionButtonsController;
	private TemperatureController mTemperatureController;
	private TemperatureController mTemperatureControllerCollapsed;
	private SeatWarmerController mSeatWarmerController;

	private boolean mInAnimation;

	// TODO: read from shared pref
	private boolean mAutoMode;

	public HvacPanelController(Context context, View container,
	WindowManager windowManager,
	TemperatureBarOverlay driverTemperatureExpanded,
	TemperatureBarOverlay passengerTemperatureExpanded,
	TemperatureBarOverlay driverTemperatureBarCollapsed,
	TemperatureBarOverlay passengerTemperatureBarCollapsed) {
	Resources res = context.getResources();
	mShowCollapsed = res.getBoolean(R.bool.config_showCollapsedBars);

	mDriverTemperatureBarCollapsed = driverTemperatureBarCollapsed;
	mPassengerTemperatureBarCollapsed = passengerTemperatureBarCollapsed;

	mCurrentState = STATE_COLLAPSED;
	mWindowManager = windowManager;

	mPanelCollapsedHeight = res.getDimensionPixelSize(R.dimen.car_hvac_panel_collapsed_height);
	mPanelFullExpandedHeight
	= res.getDimensionPixelSize(R.dimen.car_hvac_panel_full_expanded_height);

	mAutoOffDrawable = res.getDrawable(R.drawable.ic_auto_off);
	mAutoOnDrawable = res.getDrawable(R.drawable.ic_auto_on);

	mDriverTemperatureBarExpanded = driverTemperatureExpanded;
	mPassengerTemperatureBarExpanded = passengerTemperatureExpanded;

	mDriverTemperatureBarExpanded.setCloseButtonOnClickListener(mCollapseHvac);
	mPassengerTemperatureBarExpanded.setCloseButtonOnClickListener(mCollapseHvac);

	// Initially the hvac panel is collapsed, hide the expanded version.
	mDriverTemperatureBarExpanded.setVisibility(View.INVISIBLE);
	mPassengerTemperatureBarExpanded.setVisibility(View.INVISIBLE);

	mPassengerTemperatureBarCollapsed.setBarOnClickListener(mExpandHvac);
	mDriverTemperatureBarCollapsed.setBarOnClickListener(mExpandHvac);

	mContainer = container;
	mContainer.setVisibility(View.INVISIBLE);
	mContainer.setOnClickListener(mCollapseHvac);
	mPanel = mContainer.findViewById(R.id.hvac_center_panel);

	mHvacFanControlBackground = mPanel.findViewById(R.id.fan_control_bg);
	// set clickable so that clicks are not forward to the mContainer. This way a miss click
	// does not close the UI
	mPanel.setClickable(true);

	// Set up top row buttons
	mPanelTopRow = (HvacPanelRow) mContainer.findViewById(R.id.top_row);

	mAcButton = (ToggleButton) mPanelTopRow.findViewById(R.id.ac_button);
	mAcButton.setToggleIcons(res.getDrawable(R.drawable.ic_ac_on),
	res.getDrawable(R.drawable.ic_ac_off));

	mRecycleAirButton = (ToggleButton) mPanelTopRow.findViewById(R.id.recycle_air_button);

	mRecycleAirButton.setToggleIcons(res.getDrawable(R.drawable.ic_recycle_air_on),
	res.getDrawable(R.drawable.ic_recycle_air_off));

	// Setup bottom row buttons
	mPanelBottomRow = (HvacPanelRow) mContainer.findViewById(R.id.bottom_row);

	mAutoButton = (ImageView) mContainer.findViewById(R.id.auto_button);
	mAutoButton.setOnClickListener(mAutoButtonClickListener);

	mFrontDefrosterButton = (ToggleButton) mPanelBottomRow.findViewById(R.id.front_defroster);
	mRearDefrosterButton = (ToggleButton) mPanelBottomRow.findViewById(R.id.rear_defroster);

	mFrontDefrosterButton.setToggleIcons(res.getDrawable(R.drawable.ic_front_defroster_on),
	res.getDrawable(R.drawable.ic_front_defroster_off));

	mRearDefrosterButton.setToggleIcons(res.getDrawable(R.drawable.ic_rear_defroster_on),
	res.getDrawable(R.drawable.ic_rear_defroster_off));

	mFanSpeedBar = (FanSpeedBar) mContainer.findViewById(R.id.fan_speed_bar);
	mFanDirectionButtons = (FanDirectionButtons) mContainer.findViewById(R.id.fan_direction_buttons);

	mDriverSeatWarmer = (SeatWarmerButton) mContainer.findViewById(R.id.left_seat_heater);
	mPassengerSeatWarmer = (SeatWarmerButton) mContainer.findViewById(R.id.right_seat_heater);

	mHvacPowerSwitch = (ToggleButton)mPanelBottomRow.findViewById(R.id.hvac_master_switch);
	// TODO: this is not good UX design - just a placeholder
	mHvacPowerSwitch.setToggleIcons(res.getDrawable(R.drawable.ac_master_switch_on),
	res.getDrawable(R.drawable.ac_master_switch_off));

	if (!mShowCollapsed) {
	mDriverTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
	mPassengerTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
	}
	}

	public void updateHvacController(HvacController controller) {
	//TODO: handle disconnected HvacController.
	mHvacController = controller;

	mFanSpeedBarController = new FanSpeedBarController(mFanSpeedBar, mHvacController);
	mFanDirectionButtonsController
	= new FanDirectionButtonsController(mFanDirectionButtons, mHvacController);
	mTemperatureController = new TemperatureController(
	mPassengerTemperatureBarExpanded,
	mDriverTemperatureBarExpanded,
	mPassengerTemperatureBarCollapsed,
	mDriverTemperatureBarCollapsed,
	mHvacController);
	mSeatWarmerController = new SeatWarmerController(mPassengerSeatWarmer,
	mDriverSeatWarmer, mHvacController);

	// Toggle buttons do not need additional logic to map between hardware
	// and UI settings. Simply use a ToggleListener to handle clicks.
	mAcButton.setIsOn(mHvacController.getAcState());
	mAcButton.setToggleListener(new ToggleButton.ToggleListener() {
	@Override
	public void onToggled(boolean isOn) {
	mHvacController.setAcState(isOn);
	}
	});

	mFrontDefrosterButton.setIsOn(mHvacController.getFrontDefrosterState());
	mFrontDefrosterButton.setToggleListener(new ToggleButton.ToggleListener() {
	@Override
	public void onToggled(boolean isOn) {
	mHvacController.setFrontDefrosterState(isOn);
	}
	});

	mRearDefrosterButton.setIsOn(mHvacController.getRearDefrosterState());
	mRearDefrosterButton.setToggleListener(new ToggleButton.ToggleListener() {
	@Override
	public void onToggled(boolean isOn) {
	mHvacController.setRearDefrosterState(isOn);
	}
	});

	mRecycleAirButton.setIsOn(mHvacController.getAirCirculationState());
	mRecycleAirButton.setToggleListener(new ToggleButton.ToggleListener() {
	@Override
	public void onToggled(boolean isOn) {
	mHvacController.setAirCirculation(isOn);
	}
	});

	setAutoMode(mHvacController.getAutoModeState());

	mHvacPowerSwitch.setIsOn(mHvacController.getHvacPowerState());
	mHvacPowerSwitch.setToggleListener(isOn -> mHvacController.setHvacPowerState(isOn));

	mHvacController.registerCallback(mToggleButtonCallbacks);
	mToggleButtonCallbacks.onHvacPowerChange(mHvacController.getHvacPowerState());
	}

	private HvacController.Callback mToggleButtonCallbacks
	= new HvacController.Callback() {
	@Override
	public void onAirCirculationChange(boolean isOn) {
	mRecycleAirButton.setIsOn(isOn);
	}

	@Override
	public void onFrontDefrosterChange(boolean isOn) {
	mFrontDefrosterButton.setIsOn(isOn);
	}

	@Override
	public void onRearDefrosterChange(boolean isOn) {
	mRearDefrosterButton.setIsOn(isOn);
	}

	@Override
	public void onAcStateChange(boolean isOn) {
	mAcButton.setIsOn(isOn);
	}

	@Override
	public void onAutoModeChange(boolean isOn) {
	mAutoMode = isOn;
	setAutoMode(mAutoMode);
	}
	};

	/**
	* Take the listeners and animators from a {@link AnimatorSet} and merge them to the
	* input {@link Animator} and {@link android.animation.Animator.AnimatorListener} lists.
	*/
	private void combineAnimationSet(List<Animator> animatorList,
	List<Animator.AnimatorListener> listenerList, AnimatorSet set) {

	ArrayList<Animator> list = set.getChildAnimations();
	if (list != null) {
	int size = list.size();
	for (int i = 0; i < size; i++) {
	animatorList.add(list.get(i));
	}
	}

	ArrayList<Animator.AnimatorListener> listeners = set.getListeners();
	if (listeners != null) {
	int size = listeners.size();
	for (int i = 0; i < size; i++) {
	listenerList.add(listeners.get(i));
	}
	}
	}

	/**
	* Play necessary animations between {@link HvacPanelState} transitions
	*/
	private void transitionState(@HvacPanelState int startState, @HvacPanelState int endState) {
	if (startState == endState \|\| mInAnimation) {
	return;
	}

	List<Animator> animationList = new ArrayList<>();
	List<Animator.AnimatorListener> listenerList = new ArrayList<>();
	ValueAnimator heightAnimator = getPanelHeightAnimator(startState, endState);
	mTransition = new HvacPanelStateTransition(startState, endState);
	ValueAnimator fanBgAlphaAnimator;
	switch (endState) {
	case STATE_COLLAPSED:
	// Transition to collapsed state:
	// 1. Collapse the temperature bars.
	// 2. Collapse the top and bottom panel, staggered with a different delay.
	// 3. Decrease height of the hvac center panel, but maintain container height.
	// 4. Fade the background of the fan controls seperately to create staggered effect.
	animationList.add(heightAnimator);
	heightAnimator.setDuration(PANEL_COLLAPSE_ANIMATION_TIME_MS);
	fanBgAlphaAnimator
	= ObjectAnimator.ofFloat(mHvacFanControlBackground, View.ALPHA, 1, 0)
	.setDuration(PANEL_COLLAPSE_ANIMATION_TIME_MS);
	fanBgAlphaAnimator.setStartDelay(PANEL_ANIMATION_DELAY_MS);
	animationList.add(fanBgAlphaAnimator);

	ValueAnimator panelAlphaAnimator
	= ObjectAnimator.ofFloat(mContainer, View.ALPHA, 1, 0);
	panelAlphaAnimator.setDuration(200);
	panelAlphaAnimator.setStartDelay(300);

	animationList.add(panelAlphaAnimator);

	combineAnimationSet(animationList, listenerList,
	mDriverTemperatureBarExpanded.getCollapseAnimations());
	combineAnimationSet(animationList, listenerList,
	mPassengerTemperatureBarExpanded.getCollapseAnimations());

	combineAnimationSet(animationList, listenerList,
	mPanelTopRow.getCollapseAnimation(PANEL_ANIMATION_DELAY_MS,
	mTopPanelMaxAlpha));
	combineAnimationSet(animationList, listenerList,
	mPanelBottomRow.getCollapseAnimation(PANEL_ANIMATION_DELAY_MS,
	mTopPanelMaxAlpha));
	break;
	case STATE_COLLAPSED_DIMMED:
	// Hide the temperature numbers, open arrows and auto state button.
	// TODO: determine if this section is still needed.
	break;
	case STATE_FULL_EXPANDED:
	// Transition to expaneded state:
	// 1. Expand the temperature bars.
	// 2. Expand the top and bottom panel, staggered with a different delay.
	// 3. Increase height of the hvac center panel, but maintain container height.
	// 4. Fade in fan control background in a staggered manner.
	fanBgAlphaAnimator
	= ObjectAnimator.ofFloat(mHvacFanControlBackground, View.ALPHA, 0, 1)
	.setDuration(PANEL_ANIMATION_TIME_MS);
	fanBgAlphaAnimator.setStartDelay(PANEL_ANIMATION_DELAY_MS);
	animationList.add(fanBgAlphaAnimator);

	animationList.add(heightAnimator);
	combineAnimationSet(animationList, listenerList,
	mDriverTemperatureBarExpanded.getExpandAnimatons());
	combineAnimationSet(animationList, listenerList,
	mPassengerTemperatureBarExpanded.getExpandAnimatons());

	// During expansion, the bottom panel animation should be delayed
	combineAnimationSet(animationList, listenerList,
	mPanelTopRow.getExpandAnimation(PANEL_ANIMATION_DELAY_MS,
	mTopPanelMaxAlpha));
	combineAnimationSet(animationList, listenerList,
	mPanelBottomRow.getExpandAnimation(PANEL_ANIMATION_LONG_DELAY_MS, 1f));
	break;
	default:
	}

	// If there are animations for the state change, play them all together and ensure
	// the animation listeners are attached.
	if (animationList.size() > 0) {
	AnimatorSet animatorSet = new AnimatorSet();
	animatorSet.playTogether(animationList);
	for (Animator.AnimatorListener listener : listenerList) {
	animatorSet.addListener(listener);
	}
	animatorSet.addListener(mAnimatorListener);
	animatorSet.start();
	}
	}

	private AnimatorSet.AnimatorListener mAnimatorListener = new AnimatorSet.AnimatorListener() {
	@Override
	public void onAnimationStart(Animator animation) {
	mTransition.onTransitionStart();
	}

	@Override
	public void onAnimationEnd(Animator animation) {
	mTransition.onTransitionComplete();
	}

	@Override
	public void onAnimationCancel(Animator animation) {}

	@Override
	public void onAnimationRepeat(Animator animation) {}
	};

	private ValueAnimator getPanelHeightAnimator(@HvacPanelState int startState,
	@HvacPanelState int endState) {
	int startHeight = getStateHeight(startState);
	int endHeight = getStateHeight(endState);
	if (startHeight == endHeight) {
	return null;
	}

	ValueAnimator heightAnimator = new ValueAnimator().ofInt(startHeight, endHeight)
	.setDuration(PANEL_ANIMATION_TIME_MS);
	heightAnimator.addUpdateListener(mHeightUpdateListener);
	return heightAnimator;
	}

	private int getStateHeight(@HvacPanelState int state) {
	switch (state) {
	case STATE_COLLAPSED:
	case STATE_COLLAPSED_DIMMED:
	return mPanelCollapsedHeight;
	case STATE_FULL_EXPANDED:
	return mPanelFullExpandedHeight;
	default:
	throw new IllegalArgumentException("No height mapped to HVAC State: " + state);
	}
	}

	private void setAutoMode(boolean isOn) {
	if (isOn) {
	mPanelTopRow.setOnTouchListener(new View.OnTouchListener() {
	@Override
	public boolean onTouch(View v, MotionEvent event) {
	return true;
	}
	});
	mAutoMode = true;
	mPanelTopRow.disablePanel(true);
	mTopPanelMaxAlpha = DISABLED_BUTTON_ALPHA;
	mAutoButton.setImageDrawable(mAutoOnDrawable);
	} else {
	mPanelTopRow.disablePanel(false);
	mTopPanelMaxAlpha = ENABLED_BUTTON_ALPHA;
	mAutoButton.setImageDrawable(mAutoOffDrawable);
	}
	mHvacFanControlBackground.setAlpha(mTopPanelMaxAlpha);
	mPanelTopRow.setAlpha(mTopPanelMaxAlpha);
	}

	private View.OnClickListener mAutoButtonClickListener = new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	if (mAutoMode) {
	mAutoMode = false;
	} else {
	mAutoMode = true;
	}
	mHvacController.setAutoMode(mAutoMode);
	setAutoMode(mAutoMode);
	}
	};

	private View.OnClickListener mCollapseHvac = new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	if (mInAnimation) {
	return;
	}
	if (mCurrentState != STATE_COLLAPSED) {
	transitionState(mCurrentState, STATE_COLLAPSED);
	}
	}
	};

	public void toggleHvacUi() {
	if(mCurrentState != STATE_COLLAPSED) {
	mCollapseHvac.onClick(null);
	} else {
	mExpandHvac.onClick(null);
	}
	}

	public View.OnClickListener mExpandHvac = new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	if (mInAnimation) {
	return;
	}
	if (mCurrentState != STATE_FULL_EXPANDED) {
	transitionState(mCurrentState, STATE_FULL_EXPANDED);
	}
	}
	};


	private ValueAnimator.AnimatorUpdateListener mHeightUpdateListener
	= new ValueAnimator.AnimatorUpdateListener() {
	@Override
	public void onAnimationUpdate(ValueAnimator animation) {
	int height = (Integer) animation.getAnimatedValue();
	int currentHeight = mPanel.getLayoutParams().height;
	mPanel.getLayoutParams().height = height;
	mPanel.setTop(mPanel.getTop() + height - currentHeight);
	mPanel.requestLayout();
	}
	};

	/**
	* Handles the necessary setup/clean up before and after a state transition.
	*/
	private class HvacPanelStateTransition {
	private @HvacPanelState int mEndState;
	private @HvacPanelState int mStartState;

	public HvacPanelStateTransition(@HvacPanelState int startState,
	@HvacPanelState int endState) {
	mStartState = startState;
	mEndState = endState;
	}

	public void onTransitionStart() {
	mInAnimation = true;
	if (mEndState == STATE_FULL_EXPANDED) {
	mPassengerTemperatureBarExpanded.setVisibility(View.VISIBLE);
	mDriverTemperatureBarExpanded.setVisibility(View.VISIBLE);
	if (mShowCollapsed) {
	mDriverTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
	mPassengerTemperatureBarCollapsed.setVisibility(View.INVISIBLE);
	}
	mContainer.setAlpha(1);
	mContainer.setVisibility(View.VISIBLE);
	}
	}

	public void onTransitionComplete() {
	if (mEndState == STATE_COLLAPSED) {
	if (mShowCollapsed) {
	mDriverTemperatureBarCollapsed.setVisibility(View.VISIBLE);
	mPassengerTemperatureBarCollapsed.setVisibility(View.VISIBLE);
	}
	handler.postAtFrontOfQueue(() -> {
	mDriverTemperatureBarExpanded.setVisibility(View.INVISIBLE);
	mPassengerTemperatureBarExpanded.setVisibility(View.INVISIBLE);
	});
	}
	if (mStartState == STATE_FULL_EXPANDED) {
	mContainer.setVisibility(View.INVISIBLE);
	}

	// set new states
	mCurrentState = mEndState;
	mInAnimation = false;
	}
	}
	}