import * as React from 'react';
import { Component } from 'react';
import Amplify, { ConsoleLogger as Logger } from '@aws-amplify/core';
import Auth from '@aws-amplify/auth';

import AmplifyTheme from '../Amplify-UI/Amplify-UI-Theme';

const logger = new Logger('AuthStateWrapper');

export default class AuthStateWrapper extends Component {
    constructor(props) {
        super(props);

        this.handleStateChange = this.handleStateChange.bind(this);
        this.handleAuthEvent = this.handleAuthEvent.bind(this);
        this.checkUser = this.checkUser.bind(this);

        this.state = { authState: props.authState || 'signIn' };
    }

    componentWillMount() {
        const config = this.props.amplifyConfig;
        if (config) {
            Amplify.configure(config);
        }
    }

    componentDidMount() {
        this.checkUser();
    }

    handleStateChange(state, data) {
        logger.debug('authStateWrapper state change ' + state, data);
        if (state === this.state.authState) { return; }

        if (state === 'signedOut') { state = 'signIn'; }
        this.setState({ authState: state, authData: data, error: null });
        if (this.props.onStateChange) { this.props.onStateChange(state, data); }
    }

    handleAuthEvent(state, event) {
        if (event.type === 'error') {
            this.setState({ error: event.data });
        }
    }

    checkUser() {
        if (!Auth || typeof Auth.currentUser !== 'function') {
            throw new Error('No Auth module found, please ensure @aws-amplify/auth is imported');
        }
        return Auth.currentUser()
            .then(user => {
                const state = user? 'signedIn' : 'signIn';
                this.handleStateChange(state, user);
            })
            .catch(err => logger.error(err));
    }

    render() {
        const { authState, authData } = this.state;
        const theme = this.props.theme || AmplifyTheme;
        const render_children = React.Children.map(this.props.children, (child) => {
                if (!child) { return null; }
                return React.cloneElement(child, {
                    authState,
                    authData,
                    theme,
                    onStateChange: this.handleStateChange,
                    onAuthEvent: this.handleAuthEvent
                });
            });

        return (
            <div className="amplify-state-wrapper" style={theme.stateWrapper}>
                {render_children}
                {this.state.error &&
                    <div
                        className="amplify-error-section"
                        style={theme.errorSection}
                    >
                        {this.state.error}
                    </div>
                }
            </div>
        );
    }
}