import React from 'react';
import ImmutablePropTypes from 'react-immutable-proptypes';
import PropTypes from 'prop-types';
import { is } from 'immutable';
import IconButton from './icon_button';
import { defineMessages, injectIntl, FormattedMessage } from 'react-intl';
import { isIOS } from 'flavours/glitch/util/is_mobile';
import classNames from 'classnames';
import { autoPlayGif, displayMedia } from 'flavours/glitch/util/initial_state';
import { decode } from 'blurhash';

const messages = defineMessages({
  hidden: {
    defaultMessage: 'Media hidden',
    id: 'status.media_hidden',
  },
  sensitive: {
    defaultMessage: 'Sensitive',
    id: 'media_gallery.sensitive',
  },
  toggle: {
    defaultMessage: 'Click to view',
    id: 'status.sensitive_toggle',
  },
  toggle_visible: {
    defaultMessage: 'Toggle visibility',
    id: 'media_gallery.toggle_visible',
  },
  warning: {
    defaultMessage: 'Sensitive content',
    id: 'status.sensitive_warning',
  },
});

class Item extends React.PureComponent {

  static propTypes = {
    attachment: ImmutablePropTypes.map.isRequired,
    standalone: PropTypes.bool,
    index: PropTypes.number.isRequired,
    size: PropTypes.number.isRequired,
    letterbox: PropTypes.bool,
    onClick: PropTypes.func.isRequired,
    displayWidth: PropTypes.number,
    visible: PropTypes.bool.isRequired,
  };

  static defaultProps = {
    standalone: false,
    index: 0,
    size: 1,
  };

  state = {
    loaded: false,
  };

  handleMouseEnter = (e) => {
    if (this.hoverToPlay()) {
      e.target.play();
    } else if (this.hoverToPlayClassicGif()) {
      const { attachment } = this.props;
      e.target.src = attachment.get('url');
    }
  }

  handleMouseLeave = (e) => {
    if (this.hoverToPlay()) {
      e.target.pause();
      e.target.currentTime = 0;
    } else if (this.hoverToPlayClassicGif()) {
      const { attachment } = this.props;
      e.target.src = attachment.get('preview_url');
    }
  }

  hoverToPlay () {
    const { attachment } = this.props;
    return !autoPlayGif && attachment.get('type') === 'gifv';
  }

  hoverToPlayClassicGif () {
    const { attachment } = this.props;
    return !autoPlayGif && (
      attachment.get('type') === 'image' &&
      attachment.get('url').split('.').pop().startsWith('gif')
    );
  }

  handleClick = (e) => {
    const { index, onClick } = this.props;

    if (e.button === 0 && !(e.ctrlKey || e.metaKey)) {
      if (this.hoverToPlay()) {
        e.target.pause();
        e.target.currentTime = 0;
      } else if (this.hoverToPlayClassicGif()) {
        const { attachment } = this.props;
        e.target.src = attachment.get('preview_url');
      }
      e.preventDefault();
      onClick(index);
    }

    e.stopPropagation();
  }

  componentDidMount () {
    if (this.props.attachment.get('blurhash')) {
      this._decode();
    }
  }

  componentDidUpdate (prevProps) {
    if (prevProps.attachment.get('blurhash') !== this.props.attachment.get('blurhash') && this.props.attachment.get('blurhash')) {
      this._decode();
    }
  }

  _decode () {
    const hash   = this.props.attachment.get('blurhash');
    const pixels = decode(hash, 32, 32);

    if (pixels) {
      const ctx       = this.canvas.getContext('2d');
      const imageData = new ImageData(pixels, 32, 32);

      ctx.putImageData(imageData, 0, 0);
    }
  }

  setCanvasRef = c => {
    this.canvas = c;
  }

  handleImageLoad = () => {
    this.setState({ loaded: true });
  }

  render () {
    const { attachment, index, size, standalone, letterbox, displayWidth, visible } = this.props;

    let width  = 50;
    let height = 100 / Math.ceil(size/2);

    if (size === 1 || size % 2 == 1 && index == 0) {
      width = 100;
    }

    let thumbnail = '';

    if (attachment.get('type') === 'unknown') {
      return (
        <div className={classNames('media-gallery__item', { standalone })} key={attachment.get('id')} style={{ left: left, top: top, right: right, bottom: bottom, width: `${width}%`, height: `${height}%` }}>
          <a className='media-gallery__item-thumbnail' href={attachment.get('remote_url')} target='_blank' style={{ cursor: 'pointer' }}>
            <canvas width={32} height={32} ref={this.setCanvasRef} className='media-gallery__preview' />
          </a>
        </div>
      );
    } else if (attachment.get('type') === 'image') {
      const previewUrl   = attachment.get('preview_url');
      const previewWidth = attachment.getIn(['meta', 'small', 'width']);

      const originalUrl   = attachment.get('url');
      const originalWidth = attachment.getIn(['meta', 'original', 'width']);

      const hasSize = typeof originalWidth === 'number' && typeof previewWidth === 'number';

      const srcSet = hasSize ? `${originalUrl} ${originalWidth}w, ${previewUrl} ${previewWidth}w` : null;
      const sizes  = hasSize && (displayWidth > 0) ? `${displayWidth * (width / 100)}px` : null;

      const focusX = attachment.getIn(['meta', 'focus', 'x']) || 0;
      const focusY = attachment.getIn(['meta', 'focus', 'y']) || 0;
      const x      = ((focusX /  2) + .5) * 100;
      const y      = ((focusY / -2) + .5) * 100;

      const isGif  = originalUrl.split('.').pop().startsWith('gif');
      const autoPlay = !isIOS() && autoPlayGif;

      if (isGif && !autoPlay) {
        thumbnail = (
          <a
            className='media-gallery__item-thumbnail'
            href={attachment.get('remote_url') || originalUrl}
            onClick={this.handleClick}
            target='_blank'
          >
            <img
              className={letterbox ? 'letterbox' : null}
              src={previewUrl}
              sizes={sizes}
              alt={attachment.get('description')}
              title={attachment.get('description')}
              style={{ objectPosition: letterbox ? null : `${x}% ${y}%` }}
              onMouseEnter={this.handleMouseEnter}
              onMouseLeave={this.handleMouseLeave}
              onMouseDown={this.handleMouseDown}
              onLoad={this.handleImageLoad}
            />

            <span className='media-gallery__gifv__label'>GIF</span>
          </a>
        );
      } else {
        thumbnail = (
          <a
            className='media-gallery__item-thumbnail'
            href={attachment.get('remote_url') || originalUrl}
            onClick={this.handleClick}
            target='_blank'
          >
            <img
              className={letterbox ? 'letterbox' : null}
              src={previewUrl}
              srcSet={srcSet}
              sizes={sizes}
              alt={attachment.get('description')}
              title={attachment.get('description')}
              style={{ objectPosition: letterbox ? null : `${x}% ${y}%` }}
              onLoad={this.handleImageLoad}
            />
          </a>
        );
      }
    } else if (attachment.get('type') === 'gifv') {
      const autoPlay = !isIOS() && autoPlayGif;

      thumbnail = (
        <div className={classNames('media-gallery__gifv', { autoplay: autoPlay })}>
          <video
            className={`media-gallery__item-gifv-thumbnail${letterbox ? ' letterbox' : ''}`}
            aria-label={attachment.get('description')}
            title={attachment.get('description')}
            role='application'
            src={attachment.get('url')}
            onClick={this.handleClick}
            onMouseEnter={this.handleMouseEnter}
            onMouseLeave={this.handleMouseLeave}
            autoPlay={autoPlay}
            loop
            muted
          />

          <span className='media-gallery__gifv__label'>GIF</span>
        </div>
      );
    }

    return (
      <div className={classNames('media-gallery__item', { standalone, letterbox })} key={attachment.get('id')} style={{ width: `${width}%`, height: `${height}%` }}>
        <canvas width={32} height={32} ref={this.setCanvasRef} className={classNames('media-gallery__preview', { 'media-gallery__preview--hidden': visible && this.state.loaded })} />
        {visible && thumbnail}
      </div>
    );
  }

}

@injectIntl
export default class MediaGallery extends React.PureComponent {

  static propTypes = {
    sensitive: PropTypes.bool,
    standalone: PropTypes.bool,
    letterbox: PropTypes.bool,
    fullwidth: PropTypes.bool,
    hidden: PropTypes.bool,
    media: ImmutablePropTypes.list.isRequired,
    size: PropTypes.object,
    onOpenMedia: PropTypes.func.isRequired,
    intl: PropTypes.object.isRequired,
    defaultWidth: PropTypes.number,
    cacheWidth: PropTypes.func,
    visible: PropTypes.bool,
    onToggleVisibility: PropTypes.func,
  };

  static defaultProps = {
    standalone: false,
  };

  state = {
    visible: this.props.visible !== undefined ? this.props.visible : (displayMedia !== 'hide_all' && !this.props.sensitive || displayMedia === 'show_all'),
    width: this.props.defaultWidth,
  };

  componentWillReceiveProps (nextProps) {
    if (!is(nextProps.media, this.props.media) && nextProps.visible === undefined) {
      this.setState({ visible: displayMedia !== 'hide_all' && !nextProps.sensitive || displayMedia === 'show_all' });
    } else if (!is(nextProps.visible, this.props.visible) && nextProps.visible !== undefined) {
      this.setState({ visible: nextProps.visible });
    }
  }

  componentDidUpdate (prevProps) {
    if (this.node && this.node.offsetWidth && this.node.offsetWidth != this.state.width) {
      this.setState({
        width: this.node.offsetWidth,
      });
    }
  }

  handleOpen = () => {
    if (this.props.onToggleVisibility) {
      this.props.onToggleVisibility();
    } else {
      this.setState({ visible: !this.state.visible });
    }
  }

  handleClick = (index) => {
    this.props.onOpenMedia(this.props.media, index);
  }

  handleRef = (node) => {
    this.node = node;
    if (node && node.offsetWidth && node.offsetWidth != this.state.width) {
      if (this.props.cacheWidth) this.props.cacheWidth(node.offsetWidth);

      this.setState({
        width: node.offsetWidth,
      });
    }
  }

  isStandaloneEligible() {
    const { media, standalone } = this.props;
    return standalone && media.size === 1 && media.getIn([0, 'meta', 'small', 'aspect']);
  }

  render () {
    const { media, intl, sensitive, letterbox, fullwidth, defaultWidth } = this.props;
    const { visible } = this.state;
    const size = media.take(6).size;

    const width = this.state.width || defaultWidth;

    let children, spoilerButton;

    const style = {};

    const computedClass = classNames('media-gallery', { 'full-width': fullwidth });

    if (this.isStandaloneEligible() && width) {
      style.height = width / this.props.media.getIn([0, 'meta', 'small', 'aspect']);
    } else if (width) {
      style.height = width / (16/9);
    } else {
      return (<div className={computedClass} ref={this.handleRef}></div>);
    }

    if (this.isStandaloneEligible()) {
      children = <Item standalone onClick={this.handleClick} attachment={media.get(0)} displayWidth={width} visible={visible} />;
    } else {
      children = media.take(6).map((attachment, i) => <Item key={attachment.get('id')} onClick={this.handleClick} attachment={attachment} index={i} size={size} letterbox={letterbox} displayWidth={width} visible={visible} />);
    }

    if (visible) {
      spoilerButton = <IconButton title={intl.formatMessage(messages.toggle_visible)} icon='eye-slash' overlay onClick={this.handleOpen} />;
    } else {
      spoilerButton = (
        <button type='button' onClick={this.handleOpen} className='spoiler-button__overlay'>
          <span className='spoiler-button__overlay__label'>{sensitive ? <FormattedMessage id='status.sensitive_warning' defaultMessage='Sensitive content' /> : <FormattedMessage id='status.media_hidden' defaultMessage='Media hidden' />}</span>
        </button>
      );
    }

    let parts = {};

    media.map(
      (attachment, i) => {
        if (attachment.get('description')) {
          if (attachment.get('description') in parts) {
            parts[attachment.get('description')].push([i, attachment.get('url'), attachment.get('id')]);
          } else {
            parts[attachment.get('description')] = [[i, attachment.get('url'), attachment.get('id')]];
          }
        }
      }
    );

    let descriptions = Object.entries(parts).map(
      part => {
        let [desc, idx] = part;
        if (idx.length == 1) {
          let url = idx[0][1];
          return (
            <p key={idx[0][2]}>
              <strong>
                <a href={url} title={url} target='_blank' rel='nofollow noopener'>
                  Attachment #{1+idx[0][0]}
                </a>
              </strong>
              {': '} {desc}
            </p>
          );
        } else if (idx.length != 0) {
          let c=0;
          return (
            <p key={idx[0][2]}>
              <strong>
                Attachments
                {
                  idx.map(i => {
                    let url = i[1];
                    c++;
                    return (<span key={i[2]}>{c == 1 ? ' ' : ', '}<a href={url} title={url} target='_blank' rel='nofollow noopener'>#{1+i[0]}</a></span>);
                  })
                }
              </strong>
            {': '} {desc}
            </p>
          );
        }
      }
    );

    return (
      <React.Fragment>
        <div className={computedClass} style={style} ref={this.handleRef}>
          <div className={classNames('spoiler-button', { 'spoiler-button--minified': visible })}>
            {spoilerButton}
            {visible && sensitive && (
              <span className='sensitive-marker'>
                <FormattedMessage {...messages.sensitive} />
              </span>
            )}
          </div>

          {children}
        </div>

        {visible && (
          <div className='media-caption'>
            {descriptions}
          </div>
        )}
      </React.Fragment>
    );
  }

}