import React from 'react';
import {ThemeProps, themeable} from '../../theme';
import {LocaleProps, localeable} from '../../locale';
import {uncontrollable} from 'uncontrollable';
import {Fields, ConditionGroupValue, Funcs} from './types';
import ConditionGroup from './Group';
import defaultConfig, {Config} from './config';
import {
  autobind,
  findTreeIndex,
  spliceTree,
  getTree,
  mapTree,
  guid
} from '../../utils/helper';
import {findDOMNode} from 'react-dom';
import animtion from '../../utils/Animation';

export interface ConditionBuilderProps extends ThemeProps, LocaleProps {
  fields: Fields;
  funcs?: Funcs;
  showNot?: boolean;
  value?: ConditionGroupValue;
  onChange: (value: ConditionGroupValue) => void;
  config?: Config;
}

export class QueryBuilder extends React.Component<ConditionBuilderProps> {
  config = {...defaultConfig, ...this.props.config};

  dragTarget?: HTMLElement;
  // dragNextSibling: Element | null;
  ghost?: HTMLElement;
  host: HTMLElement;
  lastX: number;
  lastY: number;
  lastMoveAt: number = 0;

  @autobind
  handleDragStart(e: React.DragEvent) {
    const target = e.currentTarget;
    const item = target.closest('[data-id]') as HTMLElement;
    this.dragTarget = item;
    // this.dragNextSibling = item.nextElementSibling;
    this.host = item.closest('[data-group-id]') as HTMLElement;

    const ghost = item.cloneNode(true) as HTMLElement;
    ghost.classList.add('is-ghost');
    this.ghost = ghost;

    e.dataTransfer.setDragImage(item.firstChild as HTMLElement, 0, 0);

    target.addEventListener('dragend', this.handleDragEnd);
    document.body.addEventListener('dragover', this.handleDragOver);
    document.body.addEventListener('drop', this.handleDragDrop);
    this.lastX = e.clientX;
    this.lastY = e.clientY;

    // 应该是 chrome 的一个bug，如果你马上修改，会马上执行 dragend
    setTimeout(() => {
      item.classList.add('is-dragging');
      // item.parentElement!.insertBefore(
      //   item,
      //   item.parentElement!.firstElementChild
      // ); // 挪到第一个，主要是因为样式问题。
    }, 5);
  }

  @autobind
  handleDragOver(e: DragEvent) {
    e.preventDefault();
    const item = (e.target as HTMLElement).closest('[data-id]') as HTMLElement;

    const dx = e.clientX - this.lastX;
    const dy = e.clientY - this.lastY;
    const d = Math.max(Math.abs(dx), Math.abs(dy));
    const now = Date.now();

    // 没移动还是不要处理，免得晃动个不停。
    if (d < 5) {
      if (this.lastMoveAt === 0) {
      } else if (now - this.lastMoveAt > 500) {
        const host = (e.target as HTMLElement).closest(
          '[data-group-id]'
        ) as HTMLElement;

        if (host) {
          this.host = host;
          this.lastMoveAt = now;
          this.lastX = 0;
          this.lastY = 0;
          this.handleDragOver(e);
          return;
        }
      }
      return;
    }

    this.lastMoveAt = now;
    this.lastX = e.clientX;
    this.lastY = e.clientY;

    if (
      !item ||
      item.classList.contains('is-ghost') ||
      item.closest('[data-group-id]') !== this.host
    ) {
      return;
    }

    const container = item.parentElement!;
    const children = [].slice.apply(container!.children);

    const idx = children.indexOf(item);

    if (this.ghost!.parentElement !== container) {
      container.appendChild(this.ghost!);
    }

    const rect = item.getBoundingClientRect();
    const isAfter = dy > 0 && e.clientY > rect.top + rect.height / 2;
    const gIdx = isAfter ? idx : idx - 1;
    const cgIdx = children.indexOf(this.ghost);

    if (gIdx !== cgIdx) {
      animtion.capture(container);

      if (gIdx === children.length - 1) {
        container.appendChild(this.ghost!);
      } else {
        container.insertBefore(this.ghost!, children[gIdx + 1]);
      }

      animtion.animateAll();
    }
  }

  @autobind
  handleDragDrop() {
    const onChange = this.props.onChange;
    const fromId = this.dragTarget!.getAttribute('data-id')!;
    const toId = this.host.getAttribute('data-group-id')!;
    const children = [].slice.call(this.ghost!.parentElement!.children);
    const idx = children.indexOf(this.dragTarget);

    if (~idx) {
      children.splice(idx, 1);
    }

    const toIndex = children.indexOf(this.ghost);
    let value = this.props.value!;

    const indexes = findTreeIndex([value], item => item.id === fromId);

    if (indexes) {
      const origin = getTree([value], indexes.concat())!;
      [value] = spliceTree([value]!, indexes, 1);

      const indexes2 = findTreeIndex([value], item => item.id === toId);

      if (indexes2) {
        [value] = spliceTree([value]!, indexes2.concat(toIndex), 0, origin);
        onChange(value);
      }
    }
  }

  @autobind
  handleDragEnd(e: Event) {
    const target = e.target as HTMLElement;

    target.removeEventListener('dragend', this.handleDragEnd);
    document.body.removeEventListener('dragover', this.handleDragOver);
    document.body.removeEventListener('drop', this.handleDragDrop);

    this.dragTarget!.classList.remove('is-dragging');
    // if (this.dragNextSibling) {
    //   this.dragTarget.parentElement!.insertBefore(
    //     this.dragTarget,
    //     this.dragNextSibling
    //   );
    // } else {
    //   this.dragTarget.parentElement!.appendChild(this.dragTarget);
    // }
    delete this.dragTarget;
    // delete this.dragNextSibling;
    this.ghost!.parentElement?.removeChild(this.ghost!);
    delete this.ghost;
  }

  render() {
    const {
      classnames: cx,
      fields,
      funcs,
      onChange,
      value,
      showNot
    } = this.props;

    const normalizedValue = Array.isArray(value?.children)
      ? {
          ...value,
          children: mapTree(value!.children, (value: any) => {
            if (value.id) {
              return value;
            }

            return {
              ...value,
              id: guid()
            };
          })
        }
      : value;

    return (
      <ConditionGroup
        config={this.config}
        funcs={funcs || this.config.funcs}
        fields={fields || this.config.fields}
        value={normalizedValue as any}
        onChange={onChange}
        classnames={cx}
        removeable={false}
        onDragStart={this.handleDragStart}
        showNot={showNot}
      />
    );
  }
}

export default themeable(
  localeable(
    uncontrollable(QueryBuilder, {
      value: 'onChange'
    })
  )
);