/**
 *
 *                                  Apache License
 *                            Version 2.0, January 2004
 *                         http://www.apache.org/licenses/
 *
 *    TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
 *
 *    1. Definitions.
 *
 *       "License" shall mean the terms and conditions for use, reproduction,
 *       and distribution as defined by Sections 1 through 9 of this document.
 *
 *       "Licensor" shall mean the copyright owner or entity authorized by
 *       the copyright owner that is granting the License.
 *
 *       "Legal Entity" shall mean the union of the acting entity and all
 *       other entities that control, are controlled by, or are under common
 *       control with that entity. For the purposes of this definition,
 *       "control" means (i) the power, direct or indirect, to cause the
 *       direction or management of such entity, whether by contract or
 *       otherwise, or (ii) ownership of fifty percent (50%) or more of the
 *       outstanding shares, or (iii) beneficial ownership of such entity.
 *
 *       "You" (or "Your") shall mean an individual or Legal Entity
 *       exercising permissions granted by this License.
 *
 *       "Source" form shall mean the preferred form for making modifications,
 *       including but not limited to software source code, documentation
 *       source, and configuration files.
 *
 *       "Object" form shall mean any form resulting from mechanical
 *       transformation or translation of a Source form, including but
 *       not limited to compiled object code, generated documentation,
 *       and conversions to other media types.
 *
 *       "Work" shall mean the work of authorship, whether in Source or
 *       Object form, made available under the License, as indicated by a
 *       copyright notice that is included in or attached to the work
 *       (an example is provided in the Appendix below).
 *
 *       "Derivative Works" shall mean any work, whether in Source or Object
 *       form, that is based on (or derived from) the Work and for which the
 *       editorial revisions, annotations, elaborations, or other modifications
 *       represent, as a whole, an original work of authorship. For the purposes
 *       of this License, Derivative Works shall not include works that remain
 *       separable from, or merely link (or bind by name) to the interfaces of,
 *       the Work and Derivative Works thereof.
 *
 *       "Contribution" shall mean any work of authorship, including
 *       the original version of the Work and any modifications or additions
 *       to that Work or Derivative Works thereof, that is intentionally
 *       submitted to Licensor for inclusion in the Work by the copyright owner
 *       or by an individual or Legal Entity authorized to submit on behalf of
 *       the copyright owner. For the purposes of this definition, "submitted"
 *       means any form of electronic, verbal, or written communication sent
 *       to the Licensor or its representatives, including but not limited to
 *       communication on electronic mailing lists, source code control systems,
 *       and issue tracking systems that are managed by, or on behalf of, the
 *       Licensor for the purpose of discussing and improving the Work, but
 *       excluding communication that is conspicuously marked or otherwise
 *       designated in writing by the copyright owner as "Not a Contribution."
 *
 *       "Contributor" shall mean Licensor and any individual or Legal Entity
 *       on behalf of whom a Contribution has been received by Licensor and
 *       subsequently incorporated within the Work.
 *
 *    2. Grant of Copyright License. Subject to the terms and conditions of
 *       this License, each Contributor hereby grants to You a perpetual,
 *       worldwide, non-exclusive, no-charge, royalty-free, irrevocable
 *       copyright license to reproduce, prepare Derivative Works of,
 *       publicly display, publicly perform, sublicense, and distribute the
 *       Work and such Derivative Works in Source or Object form.
 *
 *    3. Grant of Patent License. Subject to the terms and conditions of
 *       this License, each Contributor hereby grants to You a perpetual,
 *       worldwide, non-exclusive, no-charge, royalty-free, irrevocable
 *       (except as stated in this section) patent license to make, have made,
 *       use, offer to sell, sell, import, and otherwise transfer the Work,
 *       where such license applies only to those patent claims licensable
 *       by such Contributor that are necessarily infringed by their
 *       Contribution(s) alone or by combination of their Contribution(s)
 *       with the Work to which such Contribution(s) was submitted. If You
 *       institute patent litigation against any entity (including a
 *       cross-claim or counterclaim in a lawsuit) alleging that the Work
 *       or a Contribution incorporated within the Work constitutes direct
 *       or contributory patent infringement, then any patent licenses
 *       granted to You under this License for that Work shall terminate
 *       as of the date such litigation is filed.
 *
 *    4. Redistribution. You may reproduce and distribute copies of the
 *       Work or Derivative Works thereof in any medium, with or without
 *       modifications, and in Source or Object form, provided that You
 *       meet the following conditions:
 *
 *       (a) You must give any other recipients of the Work or
 *           Derivative Works a copy of this License; and
 *
 *       (b) You must cause any modified files to carry prominent notices
 *           stating that You changed the files; and
 *
 *       (c) You must retain, in the Source form of any Derivative Works
 *           that You distribute, all copyright, patent, trademark, and
 *           attribution notices from the Source form of the Work,
 *           excluding those notices that do not pertain to any part of
 *           the Derivative Works; and
 *
 *       (d) If the Work includes a "NOTICE" text file as part of its
 *           distribution, then any Derivative Works that You distribute must
 *           include a readable copy of the attribution notices contained
 *           within such NOTICE file, excluding those notices that do not
 *           pertain to any part of the Derivative Works, in at least one
 *           of the following places: within a NOTICE text file distributed
 *           as part of the Derivative Works; within the Source form or
 *           documentation, if provided along with the Derivative Works; or,
 *           within a display generated by the Derivative Works, if and
 *           wherever such third-party notices normally appear. The contents
 *           of the NOTICE file are for informational purposes only and
 *           do not modify the License. You may add Your own attribution
 *           notices within Derivative Works that You distribute, alongside
 *           or as an addendum to the NOTICE text from the Work, provided
 *           that such additional attribution notices cannot be construed
 *           as modifying the License.
 *
 *       You may add Your own copyright statement to Your modifications and
 *       may provide additional or different license terms and conditions
 *       for use, reproduction, or distribution of Your modifications, or
 *       for any such Derivative Works as a whole, provided Your use,
 *       reproduction, and distribution of the Work otherwise complies with
 *       the conditions stated in this License.
 *
 *    5. Submission of Contributions. Unless You explicitly state otherwise,
 *       any Contribution intentionally submitted for inclusion in the Work
 *       by You to the Licensor shall be under the terms and conditions of
 *       this License, without any additional terms or conditions.
 *       Notwithstanding the above, nothing herein shall supersede or modify
 *       the terms of any separate license agreement you may have executed
 *       with Licensor regarding such Contributions.
 *
 *    6. Trademarks. This License does not grant permission to use the trade
 *       names, trademarks, service marks, or product names of the Licensor,
 *       except as required for reasonable and customary use in describing the
 *       origin of the Work and reproducing the content of the NOTICE file.
 *
 *    7. Disclaimer of Warranty. Unless required by applicable law or
 *       agreed to in writing, Licensor provides the Work (and each
 *       Contributor provides its Contributions) on an "AS IS" BASIS,
 *       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 *       implied, including, without limitation, any warranties or conditions
 *       of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
 *       PARTICULAR PURPOSE. You are solely responsible for determining the
 *       appropriateness of using or redistributing the Work and assume any
 *       risks associated with Your exercise of permissions under this License.
 *
 *    8. Limitation of Liability. In no event and under no legal theory,
 *       whether in tort (including negligence), contract, or otherwise,
 *       unless required by applicable law (such as deliberate and grossly
 *       negligent acts) or agreed to in writing, shall any Contributor be
 *       liable to You for damages, including any direct, indirect, special,
 *       incidental, or consequential damages of any character arising as a
 *       result of this License or out of the use or inability to use the
 *       Work (including but not limited to damages for loss of goodwill,
 *       work stoppage, computer failure or malfunction, or any and all
 *       other commercial damages or losses), even if such Contributor
 *       has been advised of the possibility of such damages.
 *
 *    9. Accepting Warranty or Additional Liability. While redistributing
 *       the Work or Derivative Works thereof, You may choose to offer,
 *       and charge a fee for, acceptance of support, warranty, indemnity,
 *       or other liability obligations and/or rights consistent with this
 *       License. However, in accepting such obligations, You may act only
 *       on Your own behalf and on Your sole responsibility, not on behalf
 *       of any other Contributor, and only if You agree to indemnify,
 *       defend, and hold each Contributor harmless for any liability
 *       incurred by, or claims asserted against, such Contributor by reason
 *       of your accepting any such warranty or additional liability.
 *
 *    END OF TERMS AND CONDITIONS
 *
 *    APPENDIX: How to apply the Apache License to your work.
 *
 *       To apply the Apache License to your work, attach the following
 *       boilerplate notice, with the fields enclosed by brackets "[]"
 *       replaced with your own identifying information. (Don't include
 *       the brackets!)  The text should be enclosed in the appropriate
 *       comment syntax for the file format. We also recommend that a
 *       file or class name and description of purpose be included on the
 *       same "printed page" as the copyright notice for easier
 *       identification within third-party archives.
 *
 *    Copyright 2016 Alibaba Group
 *
 *    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.taobao.weex.ui.component.list;

import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Color;
import android.graphics.Point;
import android.graphics.PointF;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.util.ArrayMap;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.text.TextUtils;
import android.util.SparseArray;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;

import com.taobao.weex.WXEnvironment;
import com.taobao.weex.WXSDKInstance;
import com.taobao.weex.annotation.JSMethod;
import com.taobao.weex.common.Constants;
import com.taobao.weex.common.OnWXScrollListener;
import com.taobao.weex.common.WXRuntimeException;
import com.taobao.weex.dom.ImmutableDomObject;
import com.taobao.weex.dom.WXDomObject;
import com.taobao.weex.ui.component.AppearanceHelper;
import com.taobao.weex.ui.component.Scrollable;
import com.taobao.weex.ui.component.WXBaseRefresh;
import com.taobao.weex.ui.component.WXComponent;
import com.taobao.weex.ui.component.WXComponentProp;
import com.taobao.weex.ui.component.WXLoading;
import com.taobao.weex.ui.component.WXRefresh;
import com.taobao.weex.ui.component.WXVContainer;
import com.taobao.weex.ui.component.helper.WXStickyHelper;
import com.taobao.weex.ui.view.listview.WXRecyclerView;
import com.taobao.weex.ui.view.listview.adapter.IOnLoadMoreListener;
import com.taobao.weex.ui.view.listview.adapter.IRecyclerAdapterListener;
import com.taobao.weex.ui.view.listview.adapter.ListBaseViewHolder;
import com.taobao.weex.ui.view.listview.adapter.RecyclerViewBaseAdapter;
import com.taobao.weex.ui.view.listview.adapter.TransformItemDecoration;
import com.taobao.weex.ui.view.listview.adapter.WXRecyclerViewOnScrollListener;
import com.taobao.weex.utils.WXLogUtils;
import com.taobao.weex.utils.WXUtils;
import com.taobao.weex.utils.WXViewUtils;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Created by sospartan on 13/12/2016.
 */

public abstract class BasicListComponent<T extends ViewGroup & ListComponentView> extends WXVContainer<T> implements
    IRecyclerAdapterListener<ListBaseViewHolder>, IOnLoadMoreListener, Scrollable {
  public static final String TRANSFORM = "transform";
  public static final String LOADMOREOFFSET = "loadmoreoffset";
  private String TAG = "BasicListComponent";
  private int mListCellCount = 0;
  private String mLoadMoreRetry = "";
  private ArrayList<ListBaseViewHolder> recycleViewList = new ArrayList<>();
  private static final Pattern transformPattern = Pattern.compile("([a-z]+)\\(([0-9\\.]+),?([0-9\\.]+)?\\)");

  private Map<String, AppearanceHelper> mAppearComponents = new HashMap<>();

  private boolean isScrollable = true;
  private ArrayMap<String, Long> mRefToViewType;
  private SparseArray<ArrayList<WXComponent>> mViewTypes;
  private WXRecyclerViewOnScrollListener mViewOnScrollListener = new WXRecyclerViewOnScrollListener(this);

  private static final int MAX_VIEWTYPE_ALLOW_CACHE = 9;
  private static boolean mAllowCacheViewHolder = true;
  private static boolean mDownForBidCacheViewHolder = false;

  private int mOffsetAccuracy = 10;
  private Point mLastReport = new Point(-1, -1);

  private RecyclerView.ItemAnimator mItemAnimator;

  /**
   * Map for storing component that is sticky.
   **/
  private Map<String, HashMap<String, WXComponent>> mStickyMap = new HashMap<>();
  private WXStickyHelper stickyHelper;


  public BasicListComponent(WXSDKInstance instance, WXDomObject node, WXVContainer parent) {
    super(instance, node, parent);
    stickyHelper = new WXStickyHelper(this);
  }

  /**
   * Measure the size of the recyclerView.
   *
   * @param width  the expected width
   * @param height the expected height
   * @return the result of measurement
   */
  @Override
  protected MeasureOutput measure(int width, int height) {
    int screenH = WXViewUtils.getScreenHeight(WXEnvironment.sApplication);
    int weexH = WXViewUtils.getWeexHeight(getInstanceId());
    int outHeight = height > (weexH >= screenH ? screenH : weexH) ? weexH - getAbsoluteY() : height;
    return super.measure(width, outHeight);
  }

  public int getOrientation() {
    return Constants.Orientation.VERTICAL;
  }

  @Override
  public void destroy() {
    super.destroy();
    if (mStickyMap != null)
      mStickyMap.clear();
    if (mViewTypes != null)
      mViewTypes.clear();
    if (mRefToViewType != null)
      mRefToViewType.clear();
  }

  @Override
  public ViewGroup.LayoutParams getChildLayoutParams(WXComponent child, View hostView, int width, int height, int left, int right, int top, int bottom) {
    ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) hostView.getLayoutParams();
    if (child instanceof WXBaseRefresh && params == null) {
      params = new LinearLayout.LayoutParams(width, height);
    } else if (params == null) {
      params = new RecyclerView.LayoutParams(width, height);
    } else {
      params.width = width;
      params.height = height;
      params.setMargins(left, 0, right, 0);
    }
    return params;
  }

  /**
   * These transform functions are supported:
   * - `scale(x,y)`: scale item, x and y should be a positive float number.
   * - `translate(x,y)`: translate item, `x` and `y` shoule be integer numbers.
   * - `opacity(n)`: change the transparency of item, `n` must in `[0,1.0]`.
   * - `rotate(n)`: rotate item, n is integer number.
   *
   * @param raw
   * @return
   */
  private RecyclerView.ItemDecoration parseTransforms(String raw) {
    if (raw == null) {
      return null;
    }
    float scaleX = 0f, scaleY = 0f;
    int translateX = 0, translateY = 0;
    float opacity = 0f;
    int rotate = 0;
    //public TransformItemDecoration(boolean isVertical,float alpha,int translateX,int translateY,int rotation,float scale)
    Matcher matcher = transformPattern.matcher(raw);
    while (matcher.find()) {
      String match = matcher.group();
      String name = matcher.group(1);
      try {
        switch (name) {
          case "scale":
            scaleX = Float.parseFloat(matcher.group(2));
            scaleY = Float.parseFloat(matcher.group(3));
            break;
          case "translate":
            translateX = Integer.parseInt(matcher.group(2));
            translateY = Integer.parseInt(matcher.group(3));
            break;
          case "opacity":
            opacity = Float.parseFloat(matcher.group(2));
            break;
          case "rotate":
            rotate = Integer.parseInt(matcher.group(2));
            break;
          default:
            WXLogUtils.e(TAG, "Invaild transform expression:" + match);
            break;
        }
      } catch (NumberFormatException e) {
        WXLogUtils.e("", e);
        WXLogUtils.e(TAG, "Invaild transform expression:" + match);
      }
    }
    return new TransformItemDecoration(getOrientation() == Constants.Orientation.VERTICAL, opacity, translateX, translateY, rotate, scaleX, scaleY);
  }

  abstract T generateListView(Context context, int orientation);

  @Override
  protected T initComponentHostView(@NonNull Context context) {
    T bounceRecyclerView = generateListView(context, getOrientation());

    String transforms = (String) getDomObject().getAttrs().get(TRANSFORM);
    if (transforms != null) {
      bounceRecyclerView.getInnerView().addItemDecoration(parseTransforms(transforms));
    }

    mItemAnimator=bounceRecyclerView.getInnerView().getItemAnimator();

    RecyclerViewBaseAdapter recyclerViewBaseAdapter = new RecyclerViewBaseAdapter<>(this);
    recyclerViewBaseAdapter.setHasStableIds(true);
    bounceRecyclerView.setRecyclerViewBaseAdapter(recyclerViewBaseAdapter);
    bounceRecyclerView.setOverScrollMode(View.OVER_SCROLL_NEVER);
    bounceRecyclerView.getInnerView().clearOnScrollListeners();
    bounceRecyclerView.getInnerView().addOnScrollListener(mViewOnScrollListener);
    bounceRecyclerView.getInnerView().addOnScrollListener(new RecyclerView.OnScrollListener() {
      @Override
      public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);

        if (newState == RecyclerView.SCROLL_STATE_IDLE) {
          for (ListBaseViewHolder holder : recycleViewList) {
            if (holder != null
                && holder.getComponent() != null
                && !holder.getComponent().isUsing()) {
              recycleImage(holder.getView());
            }
          }
          recycleViewList.clear();
        }
        List<OnWXScrollListener> listeners = getInstance().getWXScrollListeners();
        if (listeners != null && listeners.size() > 0) {
          for (OnWXScrollListener listener : listeners) {
            if (listener != null) {
              View topView = recyclerView.getChildAt(0);
              if (topView != null) {
                int y = topView.getTop();
                listener.onScrollStateChanged(recyclerView, 0, y, newState);
              }
            }
          }
        }
      }

      @Override
      public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        List<OnWXScrollListener> listeners = getInstance().getWXScrollListeners();
        if (listeners != null && listeners.size() > 0) {
          for (OnWXScrollListener listener : listeners) {
            if (listener != null) {
              listener.onScrolled(recyclerView, dx, dy);
            }
          }
        }
      }
    });
    bounceRecyclerView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
      @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
      @Override
      public void onGlobalLayout() {
        T view;
        if ((view = getHostView()) == null)
          return;
        mViewOnScrollListener.onScrolled(view.getInnerView(), 0, 0);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
          view.getViewTreeObserver().removeOnGlobalLayoutListener(this);
        } else {
          view.getViewTreeObserver().removeGlobalOnLayoutListener(this);
        }
      }
    });
    return bounceRecyclerView;
  }

  @Override
  public void bindStickStyle(WXComponent component) {
    stickyHelper.bindStickStyle(component, mStickyMap);
  }

  @Override
  public void unbindStickStyle(WXComponent component) {
    stickyHelper.unbindStickStyle(component, mStickyMap);
  }

  private
  @Nullable
  WXComponent findDirectListChild(WXComponent comp) {
    WXComponent parent;
    if (comp == null || (parent = comp.getParent()) == null) {
      return null;
    }

    if (parent instanceof WXListComponent) {
      return comp;
    }

    return findDirectListChild(parent);
  }

  @Override
  protected boolean setProperty(String key, Object param) {
    switch (key) {
      case LOADMOREOFFSET:
        return true;
      case Constants.Name.SCROLLABLE:
        boolean scrollable = WXUtils.getBoolean(param, true);
        setScrollable(scrollable);
        return true;
      case Constants.Name.OFFSET_ACCURACY:
        int accuracy = WXUtils.getInteger(param, 10);
        setOffsetAccuracy(accuracy);
        return true;
    }
    return super.setProperty(key, param);
  }

  @WXComponentProp(name = Constants.Name.SCROLLABLE)
  public void setScrollable(boolean scrollable) {
    this.isScrollable = scrollable;
    WXRecyclerView inner = getHostView().getInnerView();
    if(inner != null) {
      inner.setScrollable(scrollable);
    }
  }

  @WXComponentProp(name = Constants.Name.OFFSET_ACCURACY)
  public void setOffsetAccuracy(int accuracy) {
    float real = WXViewUtils.getRealPxByWidth(accuracy, getInstance().getViewPortWidth());
    this.mOffsetAccuracy = (int) real;
  }

  @Override
  public boolean isScrollable() {
    return isScrollable;
  }


  private void setAppearanceWatch(WXComponent component, int event, boolean enable) {
    AppearanceHelper item = mAppearComponents.get(component.getRef());
    if (item != null) {
      item.setWatchEvent(event, enable);
    } else if (!enable) {
      //Do nothing if disable target not exist.
    } else {
      WXComponent dChild = findDirectListChild(component);
      int index = mChildren.indexOf(dChild);
      if (index != -1) {
        item = new AppearanceHelper(component, index);
        item.setWatchEvent(event, true);
        mAppearComponents.put(component.getRef(), item);
      }
    }
  }

  @Override
  public void bindAppearEvent(WXComponent component) {
    setAppearanceWatch(component, AppearanceHelper.APPEAR, true);
  }

  @Override
  public void bindDisappearEvent(WXComponent component) {
    setAppearanceWatch(component, AppearanceHelper.DISAPPEAR, true);
  }

  @Override
  public void unbindAppearEvent(WXComponent component) {
    setAppearanceWatch(component, AppearanceHelper.APPEAR, false);
  }

  @Override
  public void unbindDisappearEvent(WXComponent component) {
    setAppearanceWatch(component, AppearanceHelper.DISAPPEAR, false);
  }

  @Override
  public void scrollTo(WXComponent component, Map<String, Object> options) {
    float offsetFloat = 0;
    boolean smooth = true;

    if (options != null) {
      String offsetStr = options.get(Constants.Name.OFFSET) == null ? "0" : options.get(Constants.Name.OFFSET).toString();
      smooth = WXUtils.getBoolean(options.get(Constants.Name.ANIMATED), true);
      if (offsetStr != null) {
        try {
          offsetFloat = WXViewUtils.getRealPxByWidth(Float.parseFloat(offsetStr), getInstance().getViewPortWidth());
        }catch (Exception e ){
          WXLogUtils.e("Float parseFloat error :"+e.getMessage());
        }
      }
    }

    final int offset = (int) offsetFloat;

    T bounceRecyclerView = getHostView();
    if (bounceRecyclerView == null) {
      return;
    }

    WXComponent parent = component;
    WXCell cell = null;
    while (parent != null) {
      if (parent instanceof WXCell) {
        cell = (WXCell) parent;
        break;
      }
      parent = parent.getParent();
    }

    if (cell != null) {
      final int pos = mChildren.indexOf(cell);
      final WXRecyclerView view = bounceRecyclerView.getInnerView();

      if (!smooth) {
        RecyclerView.LayoutManager layoutManager = view.getLayoutManager();
        if (layoutManager instanceof LinearLayoutManager) {
          //GridLayoutManager is also instance of LinearLayoutManager
          ((LinearLayoutManager) layoutManager).scrollToPositionWithOffset(pos, -offset);
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
          ((StaggeredGridLayoutManager) layoutManager).scrollToPositionWithOffset(pos, -offset);
        }
        //Any else?
      } else {
        view.smoothScrollToPosition(pos);
        if (offset != 0) {
          view.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
              if (newState == RecyclerView.SCROLL_STATE_IDLE) {
                if (getOrientation() == Constants.Orientation.VERTICAL) {
                  recyclerView.smoothScrollBy(0, offset);
                } else {
                  recyclerView.smoothScrollBy(offset, 0);
                }
                recyclerView.removeOnScrollListener(this);
              }
            }
          });
        }
      }
    }
  }

  @Override
  public void onBeforeScroll(int dx, int dy) {
    T bounceRecyclerView = getHostView();
    if (mStickyMap == null || bounceRecyclerView == null) {
      return;
    }
    HashMap<String, WXComponent> stickyMap = mStickyMap.get(getRef());
    if (stickyMap == null) {
      return;
    }
    Iterator<Map.Entry<String, WXComponent>> iterator = stickyMap.entrySet().iterator();
    Map.Entry<String, WXComponent> entry;
    WXComponent stickyComponent;
    while (iterator.hasNext()) {
      entry = iterator.next();
      stickyComponent = entry.getValue();

      if (stickyComponent != null && stickyComponent.getDomObject() != null
          && stickyComponent instanceof WXCell) {

        WXCell cell = (WXCell) stickyComponent;
        if (cell.getHostView() == null) {
          return;
        }

        if (stickyComponent != null && stickyComponent.getDomObject() != null
            && stickyComponent instanceof WXCell) {
          if (stickyComponent.getHostView() == null) {
            return;
          }

          RecyclerView.LayoutManager layoutManager;
          boolean beforeFirstVisibleItem = false;
          if ((layoutManager = getHostView().getInnerView().getLayoutManager()) instanceof LinearLayoutManager) {
            int fVisible = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
            int pos = mChildren.indexOf(cell);

            if (pos <= fVisible) {
              beforeFirstVisibleItem = true;
            }
          }

          int[] location = new int[2];
          stickyComponent.getHostView().getLocationOnScreen(location);
          int[] parentLocation = new int[2];
          stickyComponent.getParentScroller().getView().getLocationOnScreen(parentLocation);

          int top = location[1] - parentLocation[1];

          boolean showSticky = beforeFirstVisibleItem && cell.getLocationFromStart() >= 0 && top <= 0 && dy >= 0;
          boolean removeSticky = cell.getLocationFromStart() <= 0 && top > 0 && dy <= 0;
          if (showSticky) {
            bounceRecyclerView.notifyStickyShow(cell);
          } else if (removeSticky) {
            bounceRecyclerView.notifyStickyRemove(cell);
          }
          cell.setLocationFromStart(top);
        }
      }
    }
  }

  @Override
  public int getScrollY() {
    T bounceRecyclerView = getHostView();
    return bounceRecyclerView == null ? 0 : bounceRecyclerView.getInnerView().getScrollY();
  }

  @Override
  public int getScrollX() {
    T bounceRecyclerView = getHostView();
    return bounceRecyclerView == null ? 0 : bounceRecyclerView.getInnerView().getScrollX();
  }

  /**
   * Append a child component to the end of WXListComponent. This will not refresh the underlying
   * view immediately. The message of index of the inserted child is given to the adapter, and the
   * adapter will determine when to refresh. The default implementation of adapter will push the
   * message into a message and refresh the view in a period of time.
   *
   * @param child the inserted child
   */
  @Override
  public void addChild(WXComponent child) {
    addChild(child, -1);
  }

  @Override
  protected int getChildrenLayoutTopOffset() {
    return 0;
  }

  /**
   * @param child the inserted child
   * @param index the index of the child to be inserted.
   * @see #addChild(WXComponent)
   */
  @Override
  public void addChild(WXComponent child, int index) {
    super.addChild(child, index);

    if (child == null || index < -1) {
      return;
    }
    int count = mChildren.size();
    index = index >= count ? -1 : index;
    bindViewType(child);

    int adapterPosition = index == -1 ? mChildren.size() - 1 : index;
    T view = getHostView();
    if (view != null) {
      boolean isAddAnimation = isAddAnimation(child);
      if (isAddAnimation) {
        view.getInnerView().setItemAnimator(mItemAnimator);
      } else {
        view.getInnerView().setItemAnimator(null);
      }
      boolean isKeepScrollPosition = isKeepScrollPosition(child);
      if (isKeepScrollPosition) {
        view.getRecyclerViewBaseAdapter().notifyItemInserted(adapterPosition);
      } else {
        view.getRecyclerViewBaseAdapter().notifyItemChanged(adapterPosition);
      }
    }
    relocateAppearanceHelper();
  }

  /**
   * To determine whether an animation is needed
   * @param child
   * @return
   */
  private boolean isAddAnimation(WXComponent child) {
    ImmutableDomObject domObject = child.getDomObject();
    if (domObject != null) {
      Object attr = domObject.getAttrs().get(Constants.Name.INSERT_CELL_ANIMATION);
      if (Constants.Value.DEFAULT.equals(attr)) {
        return true;
      }
    }
    return false;
  }

  /**
   * Determine if the component needs to be fixed at the time of insertion
   * @param child Need to insert the component
   * @return fixed=true
   */
  private boolean isKeepScrollPosition(WXComponent child) {
    ImmutableDomObject domObject = child.getDomObject();
    if (domObject != null) {
      Object attr = domObject.getAttrs().get(Constants.Name.KEEP_SCROLL_POSITION);
      if (WXUtils.getBoolean(attr, false)) {
        return true;
      }
    }
    return false;
  }


  private void relocateAppearanceHelper() {
    Iterator<Map.Entry<String, AppearanceHelper>> iterator = mAppearComponents.entrySet().iterator();
    while (iterator.hasNext()) {
      Map.Entry<String, AppearanceHelper> item = iterator.next();
      AppearanceHelper value = item.getValue();
      WXComponent dChild = findDirectListChild(value.getAwareChild());
      int index = mChildren.indexOf(dChild);
      value.setCellPosition(index);
    }
  }


  /**
   * RecyclerView manage its children in a way that different from {@link WXVContainer}. Therefore,
   * {@link WXVContainer#addSubView(View, int)} is an empty implementation in {@link
   * com.taobao.weex.ui.view.listview.WXRecyclerView}
   */
  @Override
  protected void addSubView(View child, int index) {

  }

  /**
   * Remove the child from WXListComponent. This method will use {@link
   * java.util.List#indexOf(Object)} to retrieve the component to be deleted. Like {@link
   * #addChild(WXComponent)}, this method will not refresh the view immediately, the adapter will
   * decide when to refresh.
   *
   * @param child the child to be removed
   */
  @Override
  public void remove(WXComponent child, boolean destroy) {
    int index = mChildren.indexOf(child);
    if (destroy) {
      child.detachViewAndClearPreInfo();
    }
    unBindViewType(child);

    T view = getHostView();
    if (view == null) {
      return;
    }

    boolean isRemoveAnimation = isRemoveAnimation(child);
    if (isRemoveAnimation) {
      view.getInnerView().setItemAnimator(mItemAnimator);
    } else {
      view.getInnerView().setItemAnimator(null);
    }

    view.getRecyclerViewBaseAdapter().notifyItemRemoved(index);
    if (WXEnvironment.isApkDebugable()) {
      WXLogUtils.d(TAG, "removeChild child at " + index);
    }
    super.remove(child, destroy);
  }

  /**
   * To determine whether an animation is needed
   * @param child
   * @return
   */
  private boolean isRemoveAnimation(WXComponent child) {
    ImmutableDomObject domObject = child.getDomObject();
    if (domObject != null) {
      Object attr = domObject.getAttrs().get(Constants.Name.DELETE_CELL_ANIMATION);
      if (Constants.Value.DEFAULT.equals(attr)) {
        return true;
      }
    }
    return false;
  }


  @Override
  public void computeVisiblePointInViewCoordinate(PointF pointF) {
    RecyclerView view = getHostView().getInnerView();
    pointF.set(view.computeHorizontalScrollOffset(), view.computeVerticalScrollOffset());
  }

  /**
   * Recycle viewHolder and its underlying view. This may because the view is removed or reused.
   * Either case, this method will be called.
   *
   * @param holder The view holder to be recycled.
   */
  @Override
  public void onViewRecycled(ListBaseViewHolder holder) {
    long begin = System.currentTimeMillis();
    holder.setComponentUsing(false);
    if(holder.canRecycled()) {
      recycleViewList.add(holder);
    } else {
      WXLogUtils.w(TAG, "this holder can not be allowed to  recycled" );
    }
    if (WXEnvironment.isApkDebugable()) {
      WXLogUtils.d(TAG, "Recycle holder " + (System.currentTimeMillis() - begin) + "  Thread:" + Thread.currentThread().getName());
    }
  }

  /**
   * Bind the component of the position to the holder. Then flush the view.
   *
   * @param holder   viewHolder, which holds reference to the view
   * @param position position of component in WXListComponent
   */
  @Override
  public void onBindViewHolder(ListBaseViewHolder holder, int position) {
    if (holder == null) return;
    holder.setComponentUsing(true);
    WXComponent component = getChild(position);
    if (component == null
        || (component instanceof WXRefresh)
        || (component instanceof WXLoading)
        || (component.getDomObject() != null && component.getDomObject().isFixed())
        ) {
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d(TAG, "Bind WXRefresh & WXLoading " + holder);
      }
      return;
    }

    if (holder.getComponent() != null && holder.getComponent() instanceof WXCell) {
      holder.getComponent().bindData(component);
//              holder.getComponent().refreshData(component);
    }

  }

  /**
   * Create an instance of {@link ListBaseViewHolder} for the given viewType (not for the given
   * index). This method will look up for the first component that fits the viewType requirement and
   * doesn't be used. Then create the certain type of view, detach the view f[rom the component.
   *
   * @param parent   the ViewGroup into which the new view will be inserted
   * @param viewType the type of the new view
   * @return the created view holder.
   */
  @Override
  public ListBaseViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    if (mChildren != null) {
      if (mViewTypes == null)
        return createVHForFakeComponent(viewType);
      ArrayList<WXComponent> mTypes = mViewTypes.get(viewType);
      checkRecycledViewPool(viewType);
      if (mTypes == null)
        return createVHForFakeComponent(viewType);

      for (int i = 0; i < mTypes.size(); i++) {
        WXComponent component = mTypes.get(i);
        if (component == null
            || component.isUsing()) {
          continue;
        }
        if (component.getDomObject() != null && component.getDomObject().isFixed()) {
          return createVHForFakeComponent(viewType);
        } else {
          if (component instanceof WXCell) {
            if (component.getRealView() != null) {
              return new ListBaseViewHolder(component, viewType);
            } else {
              ((WXCell) component).lazy(false);
              component.createView();
              component.applyLayoutAndEvent(component);
              return new ListBaseViewHolder(component, viewType);
            }
          } else if (component instanceof WXBaseRefresh) {
            return createVHForRefreshComponent(viewType);
          } else {
            WXLogUtils.e(TAG, "List cannot include element except cell、header、fixed、refresh and loading");
            return createVHForFakeComponent(viewType);
          }
        }
      }
    }
    if (WXEnvironment.isApkDebugable()) {
      WXLogUtils.e(TAG, "Cannot find request viewType: " + viewType);
    }
    return createVHForFakeComponent(viewType);
  }

  /**
   * Forbid ViewHolder cache if viewType > MAX_VIEWTYPE_ALLOW_CACHE
   *
   * @param viewType
   */
  private void checkRecycledViewPool(int viewType) {
    try {
      if (mViewTypes.size() > MAX_VIEWTYPE_ALLOW_CACHE)
        mAllowCacheViewHolder = false;

      if (mDownForBidCacheViewHolder)
        if (getHostView() != null && getHostView().getInnerView() != null)
          getHostView().getInnerView().getRecycledViewPool().setMaxRecycledViews(viewType, 0);

      if (!mDownForBidCacheViewHolder) {
        if (!mAllowCacheViewHolder) {
          if (getHostView() != null && getHostView().getInnerView() != null) {
            for (int i = 0; i < mViewTypes.size(); i++) {
              getHostView().getInnerView().getRecycledViewPool().setMaxRecycledViews(mViewTypes.keyAt(i), 0);
            }
            mDownForBidCacheViewHolder = true;
          }
        }
      }
    } catch (Exception e) {
      WXLogUtils.e(TAG, "Clear recycledViewPool error!");
    }
  }

  /**
   * Return the child component type. The type is defined by scopeValue in .we file.
   *
   * @param position the position of the child component.
   * @return the type of certain component.
   */
  @Override
  public int getItemViewType(int position) {
    return generateViewType(getChild(position));
  }

  /**
   * ViewType will be classified into {HashMap<Integer,ArrayList<Integer>> mViewTypes}
   *
   * @param component
   */
  private void bindViewType(WXComponent component) {
    int id = generateViewType(component);

    if (mViewTypes == null) {
      mViewTypes = new SparseArray<>();
    }

    ArrayList<WXComponent> mTypes = mViewTypes.get(id);

    if (mTypes == null) {
      mTypes = new ArrayList<>();
      mViewTypes.put(id, mTypes);
    }
    mTypes.add(component);
  }

  private void unBindViewType(WXComponent component) {
    int id = generateViewType(component);

    if (mViewTypes == null)
      return;
    ArrayList<WXComponent> mTypes = mViewTypes.get(id);
    if (mTypes == null)
      return;

    mTypes.remove(component);
  }

  /**
   * generate viewtype by component
   *
   * @param component
   * @return
   */
  private int generateViewType(WXComponent component) {
    long id;
    try {
      id = Integer.parseInt(component.getDomObject().getRef());
      String type = component.getDomObject().getAttrs().getScope();

      if (!TextUtils.isEmpty(type)) {
        if (mRefToViewType == null) {
          mRefToViewType = new ArrayMap<>();
        }
        if (!mRefToViewType.containsKey(type)) {
          mRefToViewType.put(type, id);
        }
        id = mRefToViewType.get(type);

      }
    } catch (RuntimeException e) {
      WXLogUtils.eTag(TAG, e);
      id = RecyclerView.NO_ID;
      WXLogUtils.e(TAG, "getItemViewType: NO ID, this will crash the whole render system of WXListRecyclerView");
    }
    return (int) id;
  }

  /**
   * Get child component num.
   *
   * @return return the size of {@link #mChildren} if mChildren is not empty, otherwise, return 0;
   */
  @Override
  public int getItemCount() {
    return getChildCount();
  }

  @Override
  public boolean onFailedToRecycleView(ListBaseViewHolder holder) {
    if (WXEnvironment.isApkDebugable()) {
      WXLogUtils.d(TAG, "Failed to recycle " + holder);
    }
    return false;
  }

  @Override
  public long getItemId(int position) {
    long id;
    try {
      id = Long.parseLong(getChild(position).getDomObject().getRef());
    } catch (RuntimeException e) {
      WXLogUtils.e(TAG, WXLogUtils.getStackTrace(e));
      id = RecyclerView.NO_ID;
    }
    return id;
  }

  @Override
  public void onLoadMore(int offScreenY) {
    try {
      String offset = getDomObject().getAttrs().getLoadMoreOffset();

      if (TextUtils.isEmpty(offset)) {
        offset = "0";
      }

      if (offScreenY < Integer.parseInt(offset)) {
        String loadMoreRetry = getDomObject().getAttrs().getLoadMoreRetry();
        if (loadMoreRetry == null) {
          loadMoreRetry = mLoadMoreRetry;
        }

        if (mListCellCount != mChildren.size()
            || mLoadMoreRetry == null || !mLoadMoreRetry.equals(loadMoreRetry)) {
          fireEvent(Constants.Event.LOADMORE);
          mListCellCount = mChildren.size();
          mLoadMoreRetry = loadMoreRetry;
        }
      }
    } catch (Exception e) {
      WXLogUtils.d(TAG + "onLoadMore :", e);
    }
  }

  @Override
  public void notifyAppearStateChange(int firstVisible, int lastVisible, int directionX, int directionY) {
    //notify appear state
    Iterator<AppearanceHelper> it = mAppearComponents.values().iterator();
    String direction = directionY > 0 ? Constants.Value.DIRECTION_UP :
        directionY < 0 ? Constants.Value.DIRECTION_DOWN : null;
    if (getOrientation() == Constants.Orientation.HORIZONTAL && directionX != 0) {
      direction = directionX > 0 ? Constants.Value.DIRECTION_LEFT : Constants.Value.DIRECTION_RIGHT;
    }

    while (it.hasNext()) {
      AppearanceHelper item = it.next();
      WXComponent component = item.getAwareChild();

      if (!item.isWatch()) {
        continue;
      }

      boolean outOfVisibleRange = item.getCellPositionINScollable() < firstVisible || item.getCellPositionINScollable() > lastVisible;

      View view = component.getHostView();
      if (view == null) {
        continue;
      }

      boolean visible = (!outOfVisibleRange) && item.isViewVisible();

      int result = item.setAppearStatus(visible);
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d("appear", "item " + item.getCellPositionINScollable() + " result " + result);
      }
      if (result == AppearanceHelper.RESULT_NO_CHANGE) {
        continue;
      }
      component.notifyAppearStateChange(result == AppearanceHelper.RESULT_APPEAR ? Constants.Event.APPEAR : Constants.Event.DISAPPEAR, direction);
    }
  }

  private void recycleImage(View view) {
    if (view instanceof ImageView) {
      if (getInstance().getImgLoaderAdapter() != null) {
        getInstance().getImgLoaderAdapter().setImage(null, (ImageView) view,
            null, null);
      } else {
        if (WXEnvironment.isApkDebugable()) {
          throw new WXRuntimeException("getImgLoaderAdapter() == null");
        }
        WXLogUtils.e("Error getImgLoaderAdapter() == null");
      }

    } else if (view instanceof ViewGroup) {
      for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
        recycleImage(((ViewGroup) view).getChildAt(i));
      }
    }
  }

  @NonNull
  private ListBaseViewHolder createVHForFakeComponent(int viewType) {
    FrameLayout view = new FrameLayout(getContext());
    view.setBackgroundColor(Color.WHITE);
    view.setLayoutParams(new FrameLayout.LayoutParams(0, 0));
    return new ListBaseViewHolder(view, viewType);
  }


  private ListBaseViewHolder createVHForRefreshComponent(int viewType) {
    FrameLayout view = new FrameLayout(getContext());
    view.setBackgroundColor(Color.WHITE);
    view.setLayoutParams(new FrameLayout.LayoutParams(1, 1));
    view.setVisibility(View.GONE);
    return new ListBaseViewHolder(view, viewType);
  }

  @JSMethod
  public void resetLoadmore() {
    mLoadMoreRetry = "";
  }

  @Override
  public void addEvent(String type) {
    super.addEvent(type);
    if (Constants.Event.SCROLL.equals(type) && getHostView() != null && getHostView().getInnerView() != null) {
      WXRecyclerView innerView = getHostView().getInnerView();
      innerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
          super.onScrolled(recyclerView, dx, dy);
          int offsetX = recyclerView.computeHorizontalScrollOffset();
          int offsetY = recyclerView.computeVerticalScrollOffset();
          if (shouldReport(offsetX, offsetY)) {
            int contentWidth = recyclerView.getMeasuredWidth() + recyclerView.computeHorizontalScrollRange();
            int contentHeight = recyclerView.computeVerticalScrollRange();

            Map<String, Object> event = new HashMap<>(2);
            Map<String, Object> contentSize = new HashMap<>(2);
            Map<String, Object> contentOffset = new HashMap<>(2);

            contentSize.put(Constants.Name.WIDTH, WXViewUtils.getWebPxByWidth(contentWidth, getInstance().getViewPortWidth()));
            contentSize.put(Constants.Name.HEIGHT, WXViewUtils.getWebPxByWidth(contentHeight, getInstance().getViewPortWidth()));

            contentOffset.put(Constants.Name.X, - WXViewUtils.getWebPxByWidth(offsetX, getInstance().getViewPortWidth()));
            contentOffset.put(Constants.Name.Y, - WXViewUtils.getWebPxByWidth(offsetY, getInstance().getViewPortWidth()));

            event.put(Constants.Name.CONTENT_SIZE, contentSize);
            event.put(Constants.Name.CONTENT_OFFSET, contentOffset);

            fireEvent(Constants.Event.SCROLL, event);
          }
        }
      });
    }
  }

  private boolean shouldReport(int offsetX, int offsetY) {
    if (mLastReport.x == -1 && mLastReport.y == -1) {
      mLastReport.x = offsetX;
      mLastReport.y = offsetY;
      return true;
    }

    if (Math.abs(mLastReport.x - offsetX) >= mOffsetAccuracy || Math.abs(mLastReport.y - offsetY) >= mOffsetAccuracy) {
      mLastReport.x = offsetX;
      mLastReport.y = offsetY;
      return true;
    }

    return false;
  }
}
