// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
// See License.txt for license information.

import ChannelStore from 'stores/channel_store.jsx';
import TeamStore from 'stores/team_store.jsx';
import UserStore from 'stores/user_store.jsx';

import {removeUserFromChannel, makeUserChannelAdmin, makeUserChannelMember} from 'actions/channel_actions.jsx';

import * as AsyncClient from 'utils/async_client.jsx';
import * as Utils from 'utils/utils.jsx';
import {canManageMembers} from 'utils/channel_utils.jsx';

import React from 'react';
import {FormattedMessage} from 'react-intl';

export default class ChannelMembersDropdown extends React.Component {
    constructor(props) {
        super(props);

        this.handleRemoveFromChannel = this.handleRemoveFromChannel.bind(this);
        this.handleMakeChannelMember = this.handleMakeChannelMember.bind(this);
        this.handleMakeChannelAdmin = this.handleMakeChannelAdmin.bind(this);

        this.state = {
            serverError: null,
            user: null,
            role: null
        };
    }

    handleRemoveFromChannel() {
        removeUserFromChannel(
            this.props.channel.id,
            this.props.user.id,
            () => {
                AsyncClient.getChannelStats(this.props.channel.id);
            },
            (err) => {
                this.setState({serverError: err.message});
            }
        );
    }

    handleMakeChannelMember() {
        makeUserChannelMember(
            this.props.channel.id,
            this.props.user.id,
            () => {
                AsyncClient.getChannelStats(this.props.channel.id);
            },
            (err) => {
                this.setState({serverError: err.message});
            }
        );
    }

    handleMakeChannelAdmin() {
        makeUserChannelAdmin(
            this.props.channel.id,
            this.props.user.id,
            () => {
                AsyncClient.getChannelStats(this.props.channel.id);
            },
            (err) => {
                this.setState({serverError: err.message});
            }
        );
    }

    // Checks if the user this menu is for is a channel admin or not.
    isChannelAdmin() {
        if (Utils.isChannelAdmin(this.props.channelMember.roles)) {
            return true;
        }

        return false;
    }

    // Checks if the current user has the power to change the roles of this member.
    canChangeMemberRoles() {
        if (UserStore.isSystemAdminForCurrentUser()) {
            return true;
        } else if (TeamStore.isTeamAdminForCurrentTeam()) {
            return true;
        } else if (ChannelStore.isChannelAdminForCurrentChannel()) {
            return true;
        }

        return false;
    }

    // Checks if the current user has the power to remove this member from the channel.
    canRemoveMember() {
        return canManageMembers(this.props.channel, UserStore.isSystemAdminForCurrentUser(), TeamStore.isTeamAdminForCurrentTeam(), ChannelStore.isChannelAdminForCurrentChannel());
    }

    render() {
        let serverError = null;
        if (this.state.serverError) {
            serverError = (
                <div className='has-error'>
                    <label className='has-error control-label'>{this.state.serverError}</label>
                </div>
            );
        }

        if (this.props.user.id === UserStore.getCurrentId()) {
            return null;
        }

        if (this.canChangeMemberRoles()) {
            let role = (
                <FormattedMessage
                    id='channel_members_dropdown.channel_member'
                    defaultMessage='Channel Member'
                />
            );

            if (this.isChannelAdmin()) {
                role = (
                    <FormattedMessage
                        id='channel_members_dropdown.channel_admin'
                        defaultMessage='Channel Admin'
                    />
                );
            }

            let removeFromChannel = null;
            if (this.canRemoveMember()) {
                removeFromChannel = (
                    <li role='presentation'>
                        <a
                            id='removeFromChannel'
                            role='menuitem'
                            href='#'
                            onClick={this.handleRemoveFromChannel}
                        >
                            <FormattedMessage
                                id='channel_members_dropdown.remove_from_channel'
                                defaultMessage='Remove From Channel'
                            />
                        </a>
                    </li>
                );
            }

            let makeChannelMember = null;
            if (this.isChannelAdmin()) {
                makeChannelMember = (
                    <li role='presentation'>
                        <a
                            id='makeChannelMember'
                            role='menuitem'
                            href='#'
                            onClick={this.handleMakeChannelMember}
                        >
                            <FormattedMessage
                                id='channel_members_dropdown.make_channel_member'
                                defaultMessage='Make Channel Member'
                            />
                        </a>
                    </li>
                );
            }

            let makeChannelAdmin = null;
            if (!this.isChannelAdmin()) {
                makeChannelAdmin = (
                    <li role='presentation'>
                        <a
                            id='makeChannelAdmin'
                            role='menuitem'
                            href='#'
                            onClick={this.handleMakeChannelAdmin}
                        >
                            <FormattedMessage
                                id='channel_members_dropdown.make_channel_admin'
                                defaultMessage='Make Channel Admin'
                            />
                        </a>
                    </li>
                );
            }

            return (
                <div className='dropdown member-drop'>
                    <a
                        id='channelMemberDropdown'
                        href='#'
                        className='dropdown-toggle theme'
                        type='button'
                        data-toggle='dropdown'
                        aria-expanded='true'
                    >
                        <span>{role} </span>
                        <span className='fa fa-chevron-down'/>
                    </a>
                    <ul
                        className='dropdown-menu member-menu'
                        role='menu'
                    >
                        {makeChannelMember}
                        {makeChannelAdmin}
                        {removeFromChannel}
                    </ul>
                    {serverError}
                </div>
            );
        } else if (this.canRemoveMember()) {
            return (
                <button
                    id='removeMember'
                    type='button'
                    className='btn btn-danger btn-message'
                    onClick={this.handleRemoveFromChannel}
                >
                    <FormattedMessage
                        id='channel_members_dropdown.remove_member'
                        defaultMessage='Remove Member'
                    />
                </button>
            );
        } else if (this.isChannelAdmin()) {
            return (
                <div>
                    <FormattedMessage
                        id='channel_members_dropdown.channel_admin'
                        defaultMessage='Channel Admin'
                    />
                </div>
            );
        }

        return (
            <div>
                <FormattedMessage
                    id='channel_members_dropdown.channel_member'
                    defaultMessage='Channel Member'
                />
            </div>
        );
    }
}

ChannelMembersDropdown.propTypes = {
    channel: React.PropTypes.object.isRequired,
    user: React.PropTypes.object.isRequired,
    teamMember: React.PropTypes.object.isRequired,
    channelMember: React.PropTypes.object.isRequired
};