// Copyright (c) 2015 Mattermost, Inc. All Rights Reserved.
// See License.txt for license information.

import Suggestion from './suggestion.jsx';

import {autocompleteChannels} from 'actions/channel_actions.jsx';

import ChannelStore from 'stores/channel_store.jsx';

import AppDispatcher from 'dispatcher/app_dispatcher.jsx';
import {Constants, ActionTypes} from 'utils/constants.jsx';

import React from 'react';

class ChannelMentionSuggestion extends Suggestion {
    render() {
        const isSelection = this.props.isSelection;
        const item = this.props.item;

        const channelName = item.channel.display_name;
        const purpose = item.channel.purpose;

        let className = 'mentions__name';
        if (isSelection) {
            className += ' suggestion--selected';
        }

        const description = '(~' + item.channel.name + ')';

        return (
            <div
                className={className}
                onClick={this.handleClick}
            >
                <div className='mention__align'>
                    <span>
                        {channelName}
                    </span>
                    <span className='mention__channelname'>
                        {' '}
                        {description}
                    </span>
                </div>
                <div className='mention__purpose'>
                    {purpose}
                </div>
            </div>
        );
    }
}

export default class ChannelMentionProvider {
    handlePretextChanged(suggestionId, pretext) {
        const captured = (/(^|\s)(~([^~]*))$/i).exec(pretext.toLowerCase());
        if (captured) {
            const prefix = captured[3];

            autocompleteChannels(
                prefix,
                (data) => {
                    const channels = data;

                    // Wrap channels in an outer object to avoid overwriting the 'type' property.
                    const wrappedChannels = [];
                    const wrappedMoreChannels = [];
                    const moreChannels = [];
                    channels.forEach((item) => {
                        if (ChannelStore.get(item.id)) {
                            wrappedChannels.push({
                                type: Constants.MENTION_CHANNELS,
                                channel: item
                            });
                            return;
                        }

                        wrappedMoreChannels.push({
                            type: Constants.MENTION_MORE_CHANNELS,
                            channel: item
                        });

                        moreChannels.push(item);
                    });

                    const wrapped = wrappedChannels.concat(wrappedMoreChannels);
                    const mentions = wrapped.map((item) => '~' + item.channel.name);

                    AppDispatcher.handleServerAction({
                        type: ActionTypes.RECEIVED_MORE_CHANNELS,
                        channels: moreChannels
                    });

                    AppDispatcher.handleServerAction({
                        type: ActionTypes.SUGGESTION_RECEIVED_SUGGESTIONS,
                        id: suggestionId,
                        matchedPretext: captured[2],
                        terms: mentions,
                        items: wrapped,
                        component: ChannelMentionSuggestion
                    });
                }
            );
        }
    }
}
