import {
    DropdownItem,
    DropdownItemGroup,
    DropdownMenuStateless
} from '@atlaskit/dropdown-menu';
import React, { PureComponent } from 'react';
import PropTypes from 'prop-types';

import { translate } from '../../../base/i18n';

/**
 * A dropdown to select a YouTube broadcast.
 *
 * @extends Component
 */
class BroadcastsDropdown extends PureComponent {
    /**
     * Default values for {@code StreamKeyForm} component's properties.
     *
     * @static
     */
    static defaultProps = {
        broadcasts: []
    };

    /**
     * {@code BroadcastsDropdown} component's property types.
     */
    static propTypes = {
        /**
         * Broadcasts available for selection. Each broadcast item should be an
         * object with a title for display in the dropdown and a boundStreamID
         * to return in the {@link onBroadcastSelected} callback.
         */
        broadcasts: PropTypes.array,

        /**
         * Callback invoked when an item in the dropdown is selected. The
         * selected broadcast's boundStreamID will be passed back.
         */
        onBroadcastSelected: PropTypes.func,

        /**
         * The boundStreamID of the broadcast that should display as selected in
         * the dropdown.
         */
        selectedBoundStreamID: PropTypes.string,

        /**
         * Invoked to obtain translated strings.
         */
        t: PropTypes.func
    };

    /**
     * The initial state of a {@code StreamKeyForm} instance.
     *
     * @type {{
     *     isDropdownOpen: boolean
     * }}
     */
    state = {
        isDropdownOpen: false
    };

    /**
     * Initializes a new {@code BroadcastsDropdown} instance.
     *
     * @param {Props} props - The React {@code Component} props to initialize
     * the new {@code BroadcastsDropdown} instance with.
     */
    constructor(props) {
        super(props);

        // Bind event handlers so they are only bound once per instance.
        this._onDropdownOpenChange = this._onDropdownOpenChange.bind(this);
        this._onSelect = this._onSelect.bind(this);
    }

    /**
     * Implements React's {@link Component#render()}.
     *
     * @inheritdoc
     * @returns {ReactElement}
     */
    render() {
        const { broadcasts, selectedBoundStreamID, t } = this.props;

        const dropdownItems = broadcasts.map(broadcast =>
            // eslint-disable-next-line react/jsx-wrap-multilines
            <DropdownItem
                key = { broadcast.boundStreamID }
                // eslint-disable-next-line react/jsx-no-bind
                onClick = { () => this._onSelect(broadcast.boundStreamID) }>
                { broadcast.title }
            </DropdownItem>
        );
        const selected = this.props.broadcasts.find(
            broadcast => broadcast.boundStreamID === selectedBoundStreamID);
        const triggerText = (selected && selected.title)
            || t('liveStreaming.choose');

        return (
            <div className = 'broadcast-dropdown'>
                <DropdownMenuStateless
                    isOpen = { this.state.isDropdownOpen }
                    onItemActivated = { this._onSelect }
                    onOpenChange = { this._onDropdownOpenChange }
                    shouldFitContainer = { true }
                    trigger = { triggerText }
                    triggerButtonProps = {{
                        className: 'broadcast-dropdown-trigger',
                        shouldFitContainer: true
                    }}
                    triggerType = 'button'>
                    <DropdownItemGroup>
                        { dropdownItems }
                    </DropdownItemGroup>
                </DropdownMenuStateless>
            </div>
        );
    }

    /**
     * Transforms the passed in broadcasts into an array of objects that can
     * be parsed by {@code DropdownMenuStateless}.
     *
     * @param {Array<Object>} broadcasts - The YouTube broadcasts to display.
     * @private
     * @returns {Array<Object>}
     */
    _formatBroadcasts(broadcasts) {
        return broadcasts.map(broadcast => {
            return {
                content: broadcast.title,
                value: broadcast
            };
        });
    }

    /**
     * Sets the dropdown to be displayed or not based on the passed in event.
     *
     * @param {Object} dropdownEvent - The event passed from
     * {@code DropdownMenuStateless} indicating if the dropdown should be open
     * or closed.
     * @private
     * @returns {void}
     */
    _onDropdownOpenChange(dropdownEvent) {
        this.setState({
            isDropdownOpen: dropdownEvent.isOpen
        });
    }

    /**
     * Callback invoked when an item has been clicked in the dropdown menu.
     *
     * @param {Object} boundStreamID - The bound stream ID for the selected
     * broadcast.
     * @returns {void}
     */
    _onSelect(boundStreamID) {
        this.props.onBroadcastSelected(boundStreamID);
    }
}

export default translate(BroadcastsDropdown);