accounts-frontend/src/components/ui/form/Dropdown.js

import React, { PropTypes } from 'react';
import ReactDOM from 'react-dom';

import classNames from 'classnames';

import { omit } from 'functions';
import { colors, COLOR_GREEN } from 'components/ui';

import styles from './dropdown.scss';
import FormInputComponent from './FormInputComponent';

export default class Dropdown extends FormInputComponent {
    static displayName = 'Dropdown';

    static propTypes = {
        label: PropTypes.oneOfType([
            PropTypes.shape({
                id: PropTypes.string
            }),
            PropTypes.string
        ]).isRequired,
        items: PropTypes.arrayOf(PropTypes.oneOfType([
            PropTypes.string,
            PropTypes.shape({
                id: PropTypes.string
            })
        ])).isRequired,
        block: PropTypes.bool,
        color: PropTypes.oneOf(colors)
    };

    static defaultProps = {
        color: COLOR_GREEN
    };

    state = {
        isActive: false,
        activeItem: null
    };

    componentDidMount() {
        // listen to capturing phase to ensure, that our event handler will be
        // called before all other
        document.addEventListener('click', this.onBodyClick, true);
    }

    componentWillUnmount() {
        document.removeEventListener('click', this.onBodyClick);
    }

    render() {
        const { color, block, items } = this.props;
        const {isActive} = this.state;

        const activeItem = this.getActiveItem();
        const label = this.formatMessage(activeItem.label);
        const props = omit(this.props, Object.keys(Dropdown.propTypes));

        return (
            <div>
                <div className={classNames(styles[color], {
                    [styles.block]: block,
                    [styles.opened]: isActive
                })}
                    {...props}
                    onClick={this.onToggle}
                >
                    <span className={styles.label}>{label}</span>
                    <span className={styles.toggleIcon} />

                    <div className={styles.menu}>
                        {Object.entries(items).map(([value, label]) => (
                            <div className={styles.menuItem} key={value} onClick={this.onSelectItem({value, label})}>
                                {label}
                            </div>
                        ))}
                    </div>
                </div>

                {this.renderError()}
            </div>
        );
    }

    toggle() {
        this.setState({
            isActive: !this.state.isActive
        });
    }

    onSelectItem(item) {
        return (event) => {
            event.preventDefault();

            this.setState({
                activeItem: item
            });
        };
    }

    getActiveItem() {
        const {items} = this.props;
        let {activeItem} = this.state;

        if (!activeItem) {
            activeItem = {
                label: this.props.label,
                value: ''
            };

            if (!activeItem.label) {
                const firstItem = Object.entries(items)[0];
                activeItem = {
                    label: firstItem[1],
                    value: firstItem[0]
                };
            }
        }

        return activeItem;
    }

    getValue() {
        return this.getActiveItem().value;
    }

    onToggle = (event) => {
        event.preventDefault();

        this.toggle();
    };

    onBodyClick = (event) => {
        if (this.state.isActive) {
            const el = ReactDOM.findDOMNode(this);

            if (!el.contains(event.target) && el !== event.taget) {
                event.preventDefault();
                event.stopPropagation();

                this.toggle();
            }
        }
    };
}