/**
 * 级联
 *
 * @Author: Shann
 * @LastEditors: Shann
 * @Date: 2021-08-04 09:48:49
 * @LastEditTime: 2021-08-04 11:00:19
 * @Copyright: Copyright 2021-2021, all rights reserved. Essa.cn
 */
class Cascader {
    props = {
        options: Array,
    };

    state = {
        options: [],
        menus: [],
    };

    constructor() {
        this.state.options = this.flatten(this.props.options);
    }

    flatten(array, level = 1) {
        let elements = [];
        array.forEach((element) => {
            element.level = level;
            elements.push(element);
            if (
                typeof element.children !== "undefined" &&
                element.children.length > 0
            ) {
                elements = elements.concat(
                    this.flatten(element.children, level + 1)
                );
            }
        });
        return elements;
    }

    handleFocus() {
        this.state.menus.push(this.props.options)
    }

    handleBlur() {
        this.state.menus = [];
    }

    handleExpand(value) {
        let current = this.state.options.filter(
            (item) => item.value === value
        )[0];
        if (this.state.menus.length > current.level) {
            this.state.menus.splice(current.level);
        }
        if (
            typeof current.children !== "undefined" &&
            current.children.length > 0
        ) {
            this.state.menus.push(current.children);
        }
    }
}