import { IStoreState, ID, IRowDimensions, IColDimensions } from '../../index.data';
import * as R from 'rambda';
import { pickPatch } from '../../utils';
import { getAllCollapsedRowFlags } from '../selectors';
import { getAllLoadableRowFlags } from '../../scroll/VScrollBar/helper';
import { getAllLoadableColumnFlags } from '../../scroll/HScrollBar/helper';

export function setDimensions(
  state: IStoreState,
  _rowDimensions: IRowDimensions,
  _colDimensions: IColDimensions,
) {
  // console.log('setDimensions');
  // const collapsedRowIds = getAllCollapsedRowIds(state);
  const collapsedRowFlags = getAllCollapsedRowFlags(state);
  const loadableRowFlags = getAllLoadableRowFlags(state);
  const loadableColumnFlags = getAllLoadableColumnFlags(state);

  // 原理:
  // 1. 默认行高为30;
  // 2. 传入的_rowDimensions是通过dom取到的 offsetHeight/offsetTop
  // 3. rowIds通过state.rows来取, 最稳定 ( 因state.rowDimension可能存在增删, 而_rowDimensions跟算法有关 )
  // 4. 先取到height, 再计算行高
  const rowDimensions: IRowDimensions = {};
  // 找到第1个可显示行的top ( row indicator的高度 )
  const firstVisibleRow = state.rows.find(row => _rowDimensions[row.id].height > 0);
  let accTop = firstVisibleRow ? _rowDimensions[firstVisibleRow.id].top : 0;
  let offsetTop = accTop;
  for (let i = 0; i < state.rows.length; i++) {
    const row = state.rows[i];
    const height =
      (_rowDimensions[row.id] && _rowDimensions[row.id].height) ||
      (state.rowDimensions[row.id] && state.rowDimensions[row.id].height) ||
      30;
    rowDimensions[row.id] = {
      height,
      top: accTop,
      offsetTop,
      offsetHeight: loadableRowFlags[i] ? height : 0,
    };
    // if (collapsedRowIds.indexOf(row.id) < 0) accTop += height;
    if (!collapsedRowFlags[i]) accTop += height;
    if (loadableRowFlags[i]) offsetTop += height;
  }

  // 原理同上
  const colDimensions: IColDimensions = {};
  // 找到第1个可显示列的left ( column indicator的宽度 )
  const firstVisibleCol = state.columns.find(col => _colDimensions[col.id!].width > 0);
  let accLeft = firstVisibleCol ? _colDimensions[firstVisibleCol.id!].left : 0;
  let offsetLeft = accLeft;
  for (let i = 0; i < state.columns.length; i++) {
    const col = state.columns[i];
    const width = _colDimensions[col.id!].width || state.colDimensions[col.id!].width || 90;
    colDimensions[col.id!] = {
      width,
      left: accLeft,
      offsetLeft,
      offsetWidth: loadableColumnFlags[i] ? width : 0,
    };
    accLeft += width;
    if (loadableColumnFlags[i]) offsetLeft += width;
  }

  const result = pickPatch(state, {
    rowDimensions,
    colDimensions,
  });

  // return R.isEmpty(result) ? null : { ...result, readyDimensions: false };
  // 这里无论如何都应该返回readyDimensions:false
  // 原因: 有时滚动发生了, 但未满1格, 所以rowDimensions并未变化, 然后滚动完成后, ReadyDimensions 仍为true
  //      这将导致selected / presentcell 不会显示
  return { ...result, readyDimensions: false };
}

export function setContainerBox(state: IStoreState, containerBox: IStoreState['containerBox']) {
  const result = pickPatch(state, { containerBox });
  // 设置containerBox后下一步一定是setDimensions
  return R.isEmpty(result) ? null : { ...result, readyDimensions: true };
}