/*
Copyright 2015, 2016 OpenMarket Ltd

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import React from 'react';
import classNames from 'classnames';
import sdk from '../../../index';
import { getAddressType, inviteMultipleToRoom } from '../../../Invite';
import createRoom from '../../../createRoom';
import MatrixClientPeg from '../../../MatrixClientPeg';
import DMRoomMap from '../../../utils/DMRoomMap';
import rate_limited_func from '../../../ratelimitedfunc';
import dis from '../../../dispatcher';
import Modal from '../../../Modal';
import AccessibleButton from '../elements/AccessibleButton';
import q from 'q';
import Fuse from 'fuse.js';

const TRUNCATE_QUERY_LIST = 40;

/*
 * Escapes a string so it can be used in a RegExp
 * Basically just replaces: \ ^ $ * + ? . ( ) | { } [ ]
 * From http://stackoverflow.com/a/6969486
 */
function escapeRegExp(str) {
    return str.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
}

module.exports = React.createClass({
    displayName: "ChatInviteDialog",
    propTypes: {
        title: React.PropTypes.string,
        description: React.PropTypes.oneOfType([
            React.PropTypes.element,
            React.PropTypes.string,
        ]),
        value: React.PropTypes.string,
        placeholder: React.PropTypes.string,
        roomId: React.PropTypes.string,
        button: React.PropTypes.string,
        focus: React.PropTypes.bool,
        onFinished: React.PropTypes.func.isRequired
    },

    getDefaultProps: function() {
        return {
            title: "Start a chat",
            description: "Who would you like to communicate with?",
            value: "",
            placeholder: "Email, name or matrix ID",
            button: "Start Chat",
            focus: true
        };
    },

    getInitialState: function() {
        return {
            error: false,

            // List of AddressTile.InviteAddressType objects represeting
            // the list of addresses we're going to invite
            inviteList: [],

            // List of AddressTile.InviteAddressType objects represeting
            // the set of autocompletion results for the current search
            // query.
            queryList: [],
        };
    },

    componentDidMount: function() {
        if (this.props.focus) {
            // Set the cursor at the end of the text input
            this.refs.textinput.value = this.props.value;
        }
        // Create a Fuse instance for fuzzy searching this._userList
        this._fuse = new Fuse(
            // Use an empty list at first that will later be populated
            // (see this._updateUserList)
            [],
            {
                shouldSort: true,
                location: 0, // The index of the query in the test string
                distance: 5, // The distance away from location the query can be
                // 0.0 = exact match, 1.0 = match anything
                threshold: 0.3,
            }
        );
        this._updateUserList();
    },

    onButtonClick: function() {
        let inviteList = this.state.inviteList.slice();
        // Check the text input field to see if user has an unconverted address
        // If there is and it's valid add it to the local inviteList
        if (this.refs.textinput.value !== '') {
            inviteList = this._addInputToList();
            if (inviteList === null) return;
        }

        const addrTexts = inviteList.map(addr => addr.address);
        if (inviteList.length > 0) {
            if (this._isDmChat(addrTexts)) {
                const userId = inviteList[0].address;
                // Direct Message chat
                const rooms = this._getDirectMessageRooms(userId);
                if (rooms.length > 0) {
                    // A Direct Message room already exists for this user, so select a
                    // room from a list that is similar to the one in MemberInfo panel
                    const ChatCreateOrReuseDialog = sdk.getComponent(
                        "views.dialogs.ChatCreateOrReuseDialog"
                    );
                    Modal.createDialog(ChatCreateOrReuseDialog, {
                        userId: userId,
                        onFinished: (success) => {
                            if (success) {
                                this.props.onFinished(true, inviteList[0]);
                            }
                            // else show this ChatInviteDialog again
                        }
                    });
                } else {
                    this._startChat(inviteList);
                }
            } else {
                // Multi invite chat
                this._startChat(inviteList);
            }
        } else {
            // No addresses supplied
            this.setState({ error: true });
        }
    },

    onCancel: function() {
        this.props.onFinished(false);
    },

    onKeyDown: function(e) {
        if (e.keyCode === 27) { // escape
            e.stopPropagation();
            e.preventDefault();
            this.props.onFinished(false);
        } else if (e.keyCode === 38) { // up arrow
            e.stopPropagation();
            e.preventDefault();
            this.addressSelector.moveSelectionUp();
        } else if (e.keyCode === 40) { // down arrow
            e.stopPropagation();
            e.preventDefault();
            this.addressSelector.moveSelectionDown();
        } else if (this.state.queryList.length > 0 && (e.keyCode === 188 || e.keyCode === 13 || e.keyCode === 9)) { // comma or enter or tab
            e.stopPropagation();
            e.preventDefault();
            this.addressSelector.chooseSelection();
        } else if (this.refs.textinput.value.length === 0 && this.state.inviteList.length && e.keyCode === 8) { // backspace
            e.stopPropagation();
            e.preventDefault();
            this.onDismissed(this.state.inviteList.length - 1)();
        } else if (e.keyCode === 13) { // enter
            e.stopPropagation();
            e.preventDefault();
            if (this.refs.textinput.value == '') {
                // if there's nothing in the input box, submit the form
                this.onButtonClick();
            } else {
                this._addInputToList();
            }
        } else if (e.keyCode === 188 || e.keyCode === 9) { // comma or tab
            e.stopPropagation();
            e.preventDefault();
            this._addInputToList();
        }
    },

    onQueryChanged: function(ev) {
        const query = ev.target.value;
        let queryList = [];

        if (query.length < 2) {
            return;
        }

        if (this.queryChangedDebouncer) {
            clearTimeout(this.queryChangedDebouncer);
        }
        this.queryChangedDebouncer = setTimeout(() => {
            // Only do search if there is something to search
            if (query.length > 0 && query != '@') {
                // Weighted keys prefer to match userIds when first char is @
                this._fuse.options.keys = [{
                    name: 'displayName',
                    weight: query[0] === '@' ? 0.1 : 0.9,
                },{
                    name: 'userId',
                    weight: query[0] === '@' ? 0.9 : 0.1,
                }];
                queryList = this._fuse.search(query).map((user) => {
                    // Return objects, structure of which is defined
                    // by InviteAddressType
                    return {
                        addressType: 'mx',
                        address: user.userId,
                        displayName: user.displayName,
                        avatarMxc: user.avatarUrl,
                        isKnown: true,
                    }
                });

                // If the query isn't a user we know about, but is a
                // valid address, add an entry for that
                if (queryList.length == 0) {
                    const addrType = getAddressType(query);
                    if (addrType !== null) {
                        queryList[0] = {
                            addressType: addrType,
                            address: query,
                            isKnown: false,
                        };
                        if (this._cancelThreepidLookup) this._cancelThreepidLookup();
                        if (addrType == 'email') {
                            this._lookupThreepid(addrType, query).done();
                        }
                    }
                }
            }
            this.setState({
                queryList: queryList,
                error: false,
            }, () => {
                this.addressSelector.moveSelectionTop();
            });
        }, 200);
    },

    onDismissed: function(index) {
        var self = this;
        return function() {
            var inviteList = self.state.inviteList.slice();
            inviteList.splice(index, 1);
            self.setState({
                inviteList: inviteList,
                queryList: [],
            });
            if (this._cancelThreepidLookup) this._cancelThreepidLookup();
        };
    },

    onClick: function(index) {
        var self = this;
        return function() {
            self.onSelected(index);
        };
    },

    onSelected: function(index) {
        var inviteList = this.state.inviteList.slice();
        inviteList.push(this.state.queryList[index]);
        this.setState({
            inviteList: inviteList,
            queryList: [],
        });
        if (this._cancelThreepidLookup) this._cancelThreepidLookup();
    },

    _getDirectMessageRooms: function(addr) {
        const dmRoomMap = new DMRoomMap(MatrixClientPeg.get());
        const dmRooms = dmRoomMap.getDMRoomsForUserId(addr);
        const rooms = [];
        dmRooms.forEach(dmRoom => {
            let room = MatrixClientPeg.get().getRoom(dmRoom);
            if (room) {
                const me = room.getMember(MatrixClientPeg.get().credentials.userId);
                if (me.membership == 'join') {
                    rooms.push(room);
                }
            }
        });
        return rooms;
    },

    _startChat: function(addrs) {
        if (MatrixClientPeg.get().isGuest()) {
            var NeedToRegisterDialog = sdk.getComponent("dialogs.NeedToRegisterDialog");
            Modal.createDialog(NeedToRegisterDialog, {
                title: "Please Register",
                description: "Guest users can't invite users. Please register."
            });
            return;
        }

        const addrTexts = addrs.map((addr) => {
            return addr.address;
        });

        if (this.props.roomId) {
            // Invite new user to a room
            var self = this;
            inviteMultipleToRoom(this.props.roomId, addrTexts)
            .then(function(addrs) {
                var room = MatrixClientPeg.get().getRoom(self.props.roomId);
                return self._showAnyInviteErrors(addrs, room);
            })
            .catch(function(err) {
                console.error(err.stack);
                var ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
                Modal.createDialog(ErrorDialog, {
                    title: "Error",
                    description: "Failed to invite",
                });
                return null;
            })
            .done();
        } else if (this._isDmChat(addrTexts)) {
            // Start the DM chat
            createRoom({dmUserId: addrTexts[0]})
            .catch(function(err) {
                console.error(err.stack);
                var ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
                Modal.createDialog(ErrorDialog, {
                    title: "Error",
                    description: "Failed to invite user",
                });
                return null;
            })
            .done();
        } else {
            // Start multi user chat
            var self = this;
            var room;
            createRoom().then(function(roomId) {
                room = MatrixClientPeg.get().getRoom(roomId);
                return inviteMultipleToRoom(roomId, addrTexts);
            })
            .then(function(addrs) {
                return self._showAnyInviteErrors(addrs, room);
            })
            .catch(function(err) {
                console.error(err.stack);
                var ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
                Modal.createDialog(ErrorDialog, {
                    title: "Error",
                    description: "Failed to invite",
                });
                return null;
            })
            .done();
        }

        // Close - this will happen before the above, as that is async
        this.props.onFinished(true, addrTexts);
    },

    _updateUserList: new rate_limited_func(function() {
        // Get all the users
        this._userList = MatrixClientPeg.get().getUsers();
        // Remove current user
        const meIx = this._userList.findIndex((u) => {
            return u.userId === MatrixClientPeg.get().credentials.userId;
        });
        this._userList.splice(meIx, 1);

        this._fuse.set(this._userList);
    }, 500),

    _isOnInviteList: function(uid) {
        for (let i = 0; i < this.state.inviteList.length; i++) {
            if (
                this.state.inviteList[i].addressType == 'mx' &&
                this.state.inviteList[i].address.toLowerCase() === uid
            ) {
                return true;
            }
        }
        return false;
    },

    _isDmChat: function(addrTexts) {
        if (addrTexts.length === 1 &&
            getAddressType(addrTexts[0]) === "mx" &&
            !this.props.roomId
        ) {
            return true;
        } else {
            return false;
        }
    },

    _showAnyInviteErrors: function(addrs, room) {
        // Show user any errors
        var errorList = [];
        for (var addr in addrs) {
            if (addrs.hasOwnProperty(addr) && addrs[addr] === "error") {
                errorList.push(addr);
            }
        }

        if (errorList.length > 0) {
            var ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
            Modal.createDialog(ErrorDialog, {
                title: "Failed to invite the following users to the " + room.name + " room:",
                description: errorList.join(", "),
            });
        }
        return addrs;
    },

    _addInputToList: function() {
        const addressText = this.refs.textinput.value.trim();
        const addrType = getAddressType(addressText);
        const addrObj = {
            addressType: addrType,
            address: addressText,
            isKnown: false,
        };
        if (addrType == null) {
            this.setState({ error: true });
            return null;
        } else if (addrType == 'mx') {
            const user = MatrixClientPeg.get().getUser(addrObj.address);
            if (user) {
                addrObj.displayName = user.displayName;
                addrObj.avatarMxc = user.avatarUrl;
                addrObj.isKnown = true;
            }
        }

        const inviteList = this.state.inviteList.slice();
        inviteList.push(addrObj);
        this.setState({
            inviteList: inviteList,
            queryList: [],
        });
        if (this._cancelThreepidLookup) this._cancelThreepidLookup();
        return inviteList;
    },

    _lookupThreepid: function(medium, address) {
        let cancelled = false;
        // Note that we can't safely remove this after we're done
        // because we don't know that it's the same one, so we just
        // leave it: it's replacing the old one each time so it's
        // not like they leak.
        this._cancelThreepidLookup = function() {
            cancelled = true;
        }

        // wait a bit to let the user finish typing
        return q.delay(500).then(() => {
            if (cancelled) return null;
            return MatrixClientPeg.get().lookupThreePid(medium, address);
        }).then((res) => {
            if (res === null || !res.mxid) return null;
            if (cancelled) return null;

            return MatrixClientPeg.get().getProfileInfo(res.mxid);
        }).then((res) => {
            if (res === null) return null;
            if (cancelled) return null;
            this.setState({
                queryList: [{
                    // an InviteAddressType
                    addressType: medium,
                    address: address,
                    displayName: res.displayname,
                    avatarMxc: res.avatar_url,
                    isKnown: true,
                }]
            });
        });
    },

    render: function() {
        const TintableSvg = sdk.getComponent("elements.TintableSvg");
        const AddressSelector = sdk.getComponent("elements.AddressSelector");
        this.scrollElement = null;

        var query = [];
        // create the invite list
        if (this.state.inviteList.length > 0) {
            var AddressTile = sdk.getComponent("elements.AddressTile");
            for (let i = 0; i < this.state.inviteList.length; i++) {
                query.push(
                    <AddressTile key={i} address={this.state.inviteList[i]} canDismiss={true} onDismissed={ this.onDismissed(i) } />
                );
            }
        }

        // Add the query at the end
        query.push(
            <textarea key={this.state.inviteList.length}
                rows="1"
                id="textinput"
                ref="textinput"
                className="mx_ChatInviteDialog_input"
                onChange={this.onQueryChanged}
                placeholder={this.props.placeholder}
                defaultValue={this.props.value}
                autoFocus={this.props.focus}>
            </textarea>
        );

        var error;
        var addressSelector;
        if (this.state.error) {
            error = <div className="mx_ChatInviteDialog_error">You have entered an invalid contact. Try using their Matrix ID or email address.</div>;
        } else {
            const addressSelectorHeader = <div className="mx_ChatInviteDialog_addressSelectHeader">
                Searching known users
            </div>;
            addressSelector = (
                <AddressSelector ref={(ref) => {this.addressSelector = ref;}}
                    addressList={ this.state.queryList }
                    onSelected={ this.onSelected }
                    truncateAt={ TRUNCATE_QUERY_LIST }
                    header={ addressSelectorHeader }
                />
            );
        }

        return (
            <div className="mx_ChatInviteDialog" onKeyDown={this.onKeyDown}>
                <div className="mx_Dialog_title">
                    {this.props.title}
                </div>
                <AccessibleButton className="mx_ChatInviteDialog_cancel"
                        onClick={this.onCancel} >
                    <TintableSvg src="img/icons-close-button.svg" width="35" height="35" />
                </AccessibleButton>
                <div className="mx_ChatInviteDialog_label">
                    <label htmlFor="textinput">{ this.props.description }</label>
                </div>
                <div className="mx_Dialog_content">
                    <div className="mx_ChatInviteDialog_inputContainer">{ query }</div>
                    { error }
                    { addressSelector }
                </div>
                <div className="mx_Dialog_buttons">
                    <button className="mx_Dialog_primary" onClick={this.onButtonClick}>
                        {this.props.button}
                    </button>
                </div>
            </div>
        );
    }
});