content: import React from 'react';
  import PropTypes from 'prop-types';
  import ImmutablePropTypes from 'react-immutable-proptypes';
  import ImmutablePureComponent from 'react-immutable-pure-component';
  import ConversationContainer from '../containers/conversation_container';
  import ScrollableList from '../../../components/scrollable_list';
  import { debounce } from 'lodash';
  
  export default class ConversationsList extends ImmutablePureComponent {
  
    static propTypes = {
      conversations: ImmutablePropTypes.list.isRequired,
      hasMore: PropTypes.bool,
      isLoading: PropTypes.bool,
      onLoadMore: PropTypes.func,
      shouldUpdateScroll: PropTypes.func,
    };
  
    getCurrentIndex = id => this.props.conversations.findIndex(x => x.get('id') === id)
  
    handleMoveUp = id => {
      const elementIndex = this.getCurrentIndex(id) - 1;
      this._selectChild(elementIndex, true);
    }
  
    handleMoveDown = id => {
      const elementIndex = this.getCurrentIndex(id) + 1;
      this._selectChild(elementIndex, false);
    }
  
    _selectChild (index, align_top) {
      const container = this.node.node;
      const element = container.querySelector(`article:nth-of-type(${index + 1}) .focusable`);
  
      if (element) {
        if (align_top && container.scrollTop > element.offsetTop) {
          element.scrollIntoView(true);
        } else if (!align_top && container.scrollTop + container.clientHeight < element.offsetTop + element.offsetHeight) {
          element.scrollIntoView(false);
        }
        element.focus();
      }
    }
  
    setRef = c => {
      this.node = c;
    }
  
    handleLoadOlder = debounce(() => {
      const last = this.props.conversations.last();
  
      if (last && last.get('last_status')) {
        this.props.onLoadMore(last.get('last_status'));
      }
    }, 300, { leading: true })
  
    render () {
      const { conversations, onLoadMore, ...other } = this.props;
  
      return (
        <ScrollableList {...other} onLoadMore={onLoadMore && this.handleLoadOlder} scrollKey='direct' ref={this.setRef}>
          {conversations.map(item => (
            <ConversationContainer
              key={item.get('id')}
              conversationId={item.get('id')}
              onMoveUp={this.handleMoveUp}
              onMoveDown={this.handleMoveDown}
            />
          ))}
        </ScrollableList>
      );
    }
  
  }
  