require('./Layout.css');

const React = require('react');
const PropTypes = require('prop-types');
const { Switch, Route, Link, withRouter } = require('react-router-dom');
const { Motion, spring } = require('react-motion');

const WindowSize = require('./WindowSize');
const About = require('./About');
const Stats = require('./Stats');
const Home = require('./Home');

class Layout extends React.Component {
  static propTypes = {
    location: PropTypes.object,
    children: PropTypes.node
  };

  state = {
    underlineLeft: 0,
    underlineWidth: 0,
    useSpring: false,
    stats: null
  };

  adjustUnderline = (useSpring = false) => {
    let itemIndex;
    switch (this.props.location.pathname) {
      case '/stats':
        itemIndex = 1;
        break;
      case '/about':
        itemIndex = 2;
        break;
      case '/':
      default:
        itemIndex = 0;
    }

    const itemNodes = this.listNode.querySelectorAll('li');
    const currentNode = itemNodes[itemIndex];

    this.setState({
      underlineLeft: currentNode.offsetLeft,
      underlineWidth: currentNode.offsetWidth,
      useSpring
    });
  };

  componentDidMount() {
    this.adjustUnderline();

    fetch('/api/stats?period=last-month')
      .then(res => res.json())
      .then(stats => this.setState({ stats }));

    if (window.localStorage) {
      const savedStats = window.localStorage.savedStats;

      if (savedStats) this.setState({ stats: JSON.parse(savedStats) });

      window.onbeforeunload = () => {
        localStorage.savedStats = JSON.stringify(this.state.stats);
      };
    }
  }

  componentDidUpdate(prevProps) {
    if (prevProps.location.pathname !== this.props.location.pathname)
      this.adjustUnderline(true);
  }

  render() {
    const { underlineLeft, underlineWidth, useSpring } = this.state;

    const style = {
      left: useSpring
        ? spring(underlineLeft, { stiffness: 220 })
        : underlineLeft,
      width: useSpring ? spring(underlineWidth) : underlineWidth
    };

    return (
      <div className="layout">
        <WindowSize onChange={this.adjustUnderline} />
        <div className="wrapper">
          <header>
            <h1 className="layout-title">unpkg</h1>
            <nav className="layout-nav">
              <ol
                className="layout-navList"
                ref={node => (this.listNode = node)}
              >
                <li>
                  <Link to="/">Home</Link>
                </li>
                <li>
                  <Link to="/stats">Stats</Link>
                </li>
                <li>
                  <Link to="/about">About</Link>
                </li>
              </ol>
              <Motion
                defaultStyle={{ left: underlineLeft, width: underlineWidth }}
                style={style}
                children={style => (
                  <div
                    className="layout-navUnderline"
                    style={{
                      WebkitTransform: `translate3d(${style.left}px,0,0)`,
                      transform: `translate3d(${style.left}px,0,0)`,
                      width: style.width
                    }}
                  />
                )}
              />
            </nav>
          </header>
        </div>

        <Switch>
          <Route
            path="/stats"
            render={() => <Stats data={this.state.stats} />}
          />
          <Route path="/about" component={About} />
          <Route path="/" component={Home} />
        </Switch>
      </div>
    );
  }
}

module.exports = withRouter(Layout);