/* @flow */

import React from 'react';
import { Component, PropTypes } from '../../libs';

type StatusType = 'wait' | 'process' | 'finish' | 'error' | 'success';

export default class Steps extends Component {
  static defaultProps = {
    direction: 'horizontal',
    finishStatus: 'finish',
    processStatus: 'process',
    active: 0
  };

  calcProgress(status: StatusType, index: number): Object {
    let step = 100;
    const style = {};
    style.transitionDelay = 150 * index + 'ms';

    const nextStatus = this.calStatus(index + 1);
    // 前后状态不一致时，并且当前status为完成，statusLine的长度才为50%
    if (nextStatus !== status) {
      if (status === this.props.finishStatus) {
        step = 50;
      } else if (status === 'wait') {
        step = 0;
        style.transitionDelay = -150 * index + 'ms';
      }
    }

    this.props.direction === 'vertical'
      ? (style.height = step + '%')
      : (style.width = step + '%');
    return style;
  }

  calStatus(index: number): StatusType {
    const { active, finishStatus, processStatus } = this.props;
    let status = 'wait';

    if (active > index) {
      status = finishStatus;
    } else if (active === index) {
      status = processStatus;
    }

    return status;
  }

  render(): React.Element<any> {
    const { children, space, direction } = this.props;

    return (
      <div style={this.style()} className={this.className('el-steps')}>
        {React.Children.map(children, (child, index) => {
          const computedSpace = space
            ? `${space}px`
            : `${100 / children.length}%`;
          const style = direction === 'horizontal'
            ? { width: computedSpace }
            : {
                height: index === children.length - 1 ? 'auto' : computedSpace
              };
          const status = this.calStatus(index);
          const lineStyle = this.calcProgress(status, index);
          return React.cloneElement(child, {
            style,
            lineStyle,
            direction,
            status,
            stepNumber: index + 1
          });
        })}
      </div>
    );
  }
}

const statusMap = ['wait', 'process', 'finish', 'error', 'success'];

Steps.propTypes = {
  space: PropTypes.number,
  active: PropTypes.number,
  direction: PropTypes.oneOf(['vertical', 'horizontal']),
  finishStatus: PropTypes.oneOf(statusMap),
  processStatus: PropTypes.oneOf(statusMap)
};