test

package com.cy.stickheadrecycledemo.adapter

import android.graphics.Canvas
import android.graphics.Color
import android.graphics.Rect
import android.util.Log
import android.util.TypedValue
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.chad.library.adapter.base.BaseNodeAdapter
import com.chad.library.adapter.base.viewholder.BaseViewHolder
import com.cy.stickheadrecycledemo.MainActivity
import com.cy.stickheadrecycledemo.data.StickBean
import com.cy.stickheadrecycledemo.utils.dp
import kotlin.math.min

class OverAllDecoration : RecyclerView.ItemDecoration() {

    private var mHeaderHeight:Float = 0f
    private var mHeaderView:View? = null
    private var mHeadPosition = 0

    override fun getItemOffsets(
        outRect: Rect,
        view: View,
        parent: RecyclerView,
        state: RecyclerView.State
    ) {
        val manager = parent.layoutManager
        val childPosition = parent.getChildAdapterPosition(view)
        if (isHead(childPosition,parent)){
            outRect.top = 10.dp
        }
    }

    override fun onDrawOver(c: Canvas, parent: RecyclerView, state: RecyclerView.State) {
        if (mHeaderHeight==0f){
            mHeaderHeight = getHeadHeight(parent)
        }
        val linearLayoutManager = parent.layoutManager as LinearLayoutManager
        val firstPosition = linearLayoutManager.findFirstVisibleItemPosition()
        val firstCompletePosition = linearLayoutManager.findFirstCompletelyVisibleItemPosition()
        if (!isHead(firstCompletePosition,parent)){
//            if (isHead(firstPosition,parent)){
//                mHeaderView = parent.findViewHolderForAdapterPosition(firstPosition)?.itemView
//                Log.e(">>>","mHeaderView：${mHeaderView}")
//            }
val findViewHolderForLayoutPosition =
                parent.findViewHolderForLayoutPosition(firstPosition) ?: return
if (parent.top < findViewHolderForLayoutPosition.itemView.top){
                return
            }
            if (isHead(firstPosition,parent)){
                addStickHead(parent, firstPosition)
            }
            mHeaderView?.measure(View.MeasureSpec.makeMeasureSpec(parent.measuredWidth,View.MeasureSpec.EXACTLY),
                View.MeasureSpec.makeMeasureSpec(parent.measuredWidth,View.MeasureSpec.AT_MOST))
            mHeaderView?.layout(0,0,parent.width, mHeaderHeight.toInt())
            mHeaderView?.draw(c)

            return
        }
        if (!isHead(firstPosition,parent)&&isHead(firstCompletePosition,parent)){
            val view =
                parent.findViewHolderForAdapterPosition(firstPosition)?.itemView ?: return
            val bottom = min(view.bottom.toFloat(),mHeaderHeight)
            c.translate(0f,bottom - mHeaderHeight )
            mHeaderView?.draw(c)
//            mHeaderView?.translationY = bottom - mHeaderHeight
        }

    }

    private fun addStickHead(
        parent: RecyclerView,
        firstPosition: Int
    ) {
        val tvHeader = TextView(parent.context)
        tvHeader.layoutParams = ViewGroup.LayoutParams(
            ViewGroup.LayoutParams.MATCH_PARENT,
            ViewGroup.LayoutParams.WRAP_CONTENT
        )
        tvHeader.setTextSize(TypedValue.COMPLEX_UNIT_SP, 20f)
        tvHeader.setPadding(20.dp, 10.dp, 20.dp, 10.dp)
        tvHeader.setBackgroundColor(Color.parseColor("#71DFE7"))
        BaseViewHolder(tvHeader)
        val adapter = parent.adapter as BaseNodeAdapter
        if (adapter.data.get(firstPosition) is StickBean) {
            val stickBean = adapter.data.get(firstPosition) as StickBean
            tvHeader.text = stickBean.head
            Log.e(">>>","stickBean.head:${stickBean.head}")
            tvHeader.setOnClickListener {
                adapter.collapse(mHeadPosition,true)
            }
        }
        mHeaderView = tvHeader
    }

    private fun getHeadHeight(parent: RecyclerView): Float {
        val view =
            parent.findViewHolderForAdapterPosition(0)?.itemView ?: return 0f
        Log.e(">>","view.height:${view.height}")
        return view.height.toFloat()
    }

    private fun isHead(position: Int, parent: RecyclerView) :Boolean{
        if (position <0){
            return false
        }
        val vh = parent.findViewHolderForAdapterPosition(position)
        parent.findViewHolderForLayoutPosition(position)
        val itemViewType = parent.adapter?.getItemViewType(position)
        if (itemViewType == 1){
            mHeadPosition = position
        }
        return itemViewType == 1
    }
    
}