import React from 'react';

export default class Slider extends React.Component {

  static defaultProps = {
    axis: false,
    min: 0,
    max: 1
  };

  static PropTypes = {
    axis: React.PropTypes.bool,
    axisUnit: React.PropTypes.string,
    min: React.PropTypes.number,
    max: React.PropTypes.number,
    onChange: React.PropTypes.func.isRequired,
  };

  constructor(props) {
    super(props);

    this.down = this.down.bind(this);
    this.up = this.up.bind(this);
  }

  down(e) {
    let rect = e.currentTarget.getBoundingClientRect();
    this.move = this.updatePercent.bind(this, rect.left, rect.width);
    this.move(e);
    document.addEventListener("mousemove", this.move);
    document.addEventListener("mouseup", this.up);
  }

  up() {
    document.removeEventListener("mousemove", this.move);
    document.removeEventListener("mouseup", this.up);
  }

  componentWillUnmount(){
    this.up();
  }

  updatePercent(left, width, event) {
    this.props.onChange(Math.min(Math.max((event.clientX - left) / width, 0), 1));
  }

  render() {
    let pctStr = (this.props.percent * 100) + '%';
    let { axis, axisUnit, min, max } = this.props;
    let axisGroup;

    if (axis) {
      axisGroup = <g style={{ fontSize: '.7em' }}>
        <text className='primary-disabled' y="3em" x="0" style={{ textAnchor: 'middle' }}>{min + axisUnit}</text>
        <text className='primary-disabled' y="3em" x="50%" style={{ textAnchor: 'middle' }}>{(min + max / 2) + axisUnit}</text>
        <text className='primary-disabled' y="3em" x="99%" style={{ textAnchor: 'middle' }}>{max + axisUnit}</text>
      </g>;
    }

    return <svg style={{ width: '100%', height: axis ? '2.5em' : '1.5em', padding: '0 0.6em', cursor: 'col-resize', boxSizing: 'border-box' }}>
      <rect className='primary' style={{ opacity: 0.3 }} y='0.25em' rx='0.3em' ry='0.3em' width='100%' height='0.7em' />
      <rect className='primary-disabled'y='0.45em' rx='0.15em' ry='0.15em' width={pctStr} height='0.3em' />
      <circle className='primary' r='0.6em' cy='0.6em' cx={pctStr} />
      <rect width='100%' height='100%' fillOpacity='0' onMouseDown={this.down}/>
      {axisGroup}
    </svg>;
  }
}
