/* @flow */

import React from 'react';
import { PropTypes, Component } from '../../libs';
import { require_condition } from '../../libs/utils';
import Node from './Node';
import Locale from '../locale';
import TreeStore from './model/tree-store';

type State = {
  currentNode: ?Object,
  store: any,
};

export default class Tree extends Component {
  state: State;

  constructor(props: Object) {
    super(props);
    const {
      data, lazy, options, load, defaultCheckedKeys, defaultExpandedKeys, currentNodeKey, nodeKey,
      checkStrictly, autoExpandParent, defaultExpandAll, filterNodeMethod } = this.props;
    this.state = {
      store: new TreeStore({
        key: nodeKey, data, lazy, props: options, load, currentNodeKey, checkStrictly,
        defaultCheckedKeys, defaultExpandedKeys, autoExpandParent, defaultExpandAll, filterNodeMethod
      }),
      currentNode: null
    };

  }

  componentWillReceiveProps(nextProps: Object): void {
    if (nextProps.data instanceof Array) {
      this.root.setData(nextProps.data);
      this.setState({}); //force update
    }
  }


  get root(): any{
    return this.state.store.root;
  }

  get store(): any {
    return this.state.store
  }


  filter(value: any) {
    if (!this.props.filterNodeMethod) throw new Error('[Tree] filterNodeMethod is required when filter');
    this.store.filter(value);
    this.refresh();
  }

  refresh(){
    this.setState({})
  }

  getNodeKey(node: any, otherwise: number) {
    const nodeKey = this.props.nodeKey;
    if (nodeKey && node) {
      return node.data[nodeKey];
    }
    return otherwise;
  }

  getCheckedNodes(leafOnly: boolean): void {
    return this.store.getCheckedNodes(leafOnly);
  }

  getCheckedKeys(leafOnly: boolean) {
    return this.store.getCheckedKeys(leafOnly);
  }

  setCheckedNodes(nodes: any, leafOnly: boolean) {
    if (!this.props.nodeKey) throw new Error('[Tree] nodeKey is required in setCheckedNodes');
    this.store.setCheckedNodes(nodes, leafOnly);
  }

  setCheckedKeys(keys: any, leafOnly: boolean) {
    if (!this.props.nodeKey) throw new Error('[Tree] nodeKey is required in setCheckedNodes');
    this.store.setCheckedKeys(keys, leafOnly);
  }

  setChecked(data: any, checked: boolean, deep: boolean) {
    this.store.setChecked(data, checked, deep);
  }

  // used by child nodes, use tree store to store this info?
  getCurrentNode(): ?Object {
    return this.state.currentNode;
  }

  setCurrentNode(node: Object): void {
    require_condition(node != null);

    let {onCurrentChange, onNodeClicked} = this.props;
    this.store.setCurrentNode(node);
    this.setState({
      currentNode: node
    }, ()=>{
      let nodeModel = node.props.nodeModel;
      onCurrentChange(nodeModel.data, node)
      onNodeClicked(nodeModel.data, node)
    });
  }

  closeSiblings(exclude: any){
    const {accordion} = this.props;
    if (!accordion) return;
    if (!this.root.childNodes || !this.root.childNodes.length) return;

    this.root.childNodes.filter(e=> e !== exclude).forEach(e=>e.collapse());
    this.refresh();
  }

  render(): React.Element<any> {
    const {
      options,
      renderContent,
      highlightCurrent,
      isShowCheckbox,
      onCheckChange,
      onNodeClicked,
      emptyText
    } = this.props;

    const renderEmptyText = ()=>{
      if (!this.root.childNodes || this.root.childNodes.length === 0){
        return (
          <div className="el-tree__empty-block">
            <span className="el-tree__empty-text">{emptyText}</span>
          </div>
        )
      } else return null;
    }

    return (
      <div
        style={this.style()}
        className={this.className('el-tree', {
          'el-tree--highlight-current': highlightCurrent
        })}
      >
        {this.root.childNodes.map((e, idx) => {
          return (
            <Node
              ref="cnode"
              key={this.getNodeKey(e,idx)}
              nodeModel={e}
              options={options}
              renderContent={renderContent}
              treeNode={this}
              parent={this}
              isShowCheckbox={isShowCheckbox}
              onCheckChange={onCheckChange}
            />
          );
        })}
        {renderEmptyText()}
      </div>
    );
  }
}

Tree.propTypes = {
  autoExpandParent: PropTypes.bool,
  checkStrictly: PropTypes.bool,
  currentNodeKey: PropTypes.any,
  defaultCheckedKeys: PropTypes.array,
  defaultExpandedKeys: PropTypes.array,
  defaultExpandAll: PropTypes.bool,
  data: PropTypes.array,
  emptyText: PropTypes.string,
  expandOnClickNode: PropTypes.bool,
  filterNodeMethod: PropTypes.func,
  renderContent: PropTypes.func,
  isShowCheckbox: PropTypes.bool,
  accordion: PropTypes.bool,
  indent: PropTypes.number,
  nodeKey: PropTypes.string,
  options: PropTypes.shape({
    children: PropTypes.string,
    label: PropTypes.string,
    icon: PropTypes.string
  }), //equal to props in vue element
  lazy: PropTypes.bool, //todo: check this
  highlightCurrent: PropTypes.bool,
  // (f:(resolve, reject)=>Unit)=>Unit
  load: PropTypes.func,
  //
  onCheckChange: PropTypes.func,
  // todo: 这个地方需要改下， 现在是current和nodeclick一起被设置上了
  // (nodeModel.data, node)=>Unit
  onNodeClicked: PropTypes.func,
  // (nodeModel.data, node)=>Unit
  onCurrentChange: PropTypes.func,
  // (nodeModel.data, nodeModel, Node)=>Unit
  onNodeExpand: PropTypes.func,
  onNodeCollapse: PropTypes.func,
};

Tree.defaultProps = {
  autoExpandParent: true,
  defaultCheckedKeys: [],
  defaultExpandedKeys: [],
  data: [],
  expandOnClickNode: true,
  emptyText: Locale.t('el.tree.emptyText'),
  indent: 16,
  options: { children: 'children', label: 'label', icon: 'icon' },
  onCheckChange() {},
  onNodeClicked() {},
  onCurrentChange(){},
  onNodeExpand(){},
  onNodeCollapse(){},
};