import React, { Component } from 'react';
import Link from 'gatsby-link';
import classnames from 'classnames';

import DocSearch from './docsearch';

import logo from '../img/netlify-cms-logo.svg';

import '../css/imports/header.css';

class Header extends Component {
  state = {
    scrolled: false,
  };

  componentDidMount() {
    // TODO: use raf to throttle events
    window.addEventListener('scroll', this.handleScroll);
  }

  componentWillUnmount() {
    window.removeEventListener('scroll', this.handleScroll);
  }

  handleScroll = () => {
    const currentWindowPos = document.documentElement.scrollTop || document.body.scrollTop;

    const scrolled = currentWindowPos > 0;

    this.setState({
      scrolled,
    });
  };

  render() {
    const { location } = this.props;
    const { scrolled } = this.state;

    const isDocs = location.pathname.indexOf('docs') !== -1;
    const isBlog = location.pathname.indexOf('blog') !== -1;

    return (
      <header
        id="header"
        className={classnames({
          docs: isDocs,
          blog: isBlog,
          scrolled,
        })}
      >
        <div className="contained">
          <div className="logo-container">
            <Link to="/" className="logo">
              <img src={logo} />
            </Link>
            {isDocs && <DocSearch />}
          </div>
          <div className="nav-container">
            <Link className="nav-link docs-link" to="/docs/intro">
              Docs
            </Link>
            <Link className="nav-link contributing-link" to="/docs/contributor-guide">
              Contributing
            </Link>
            <Link className="nav-link" to="/community">
              Community
            </Link>
            <Link className="nav-link" to="/blog">
              Blog
            </Link>
            <span className="gh-button">
              <a
                id="ghstars"
                className="github-button"
                href="https://github.com/netlify/netlify-cms"
                data-icon="octicon-star"
                data-show-count="true"
                aria-label="Star netlify/netlify-cms on GitHub"
              >
                Star
              </a>
            </span>
          </div>
        </div>
      </header>
    );
  }
}

export default Header;