/*
Copyright 2017 Vector Creations 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.
*/

'use strict';

import url from 'url';
import qs from 'querystring';
import React from 'react';
import MatrixClientPeg from '../../../MatrixClientPeg';
import PlatformPeg from '../../../PlatformPeg';
import ScalarAuthClient from '../../../ScalarAuthClient';
import WidgetMessaging from '../../../WidgetMessaging';
import TintableSvgButton from './TintableSvgButton';
import SdkConfig from '../../../SdkConfig';
import Modal from '../../../Modal';
import { _t, _td } from '../../../languageHandler';
import sdk from '../../../index';
import AppPermission from './AppPermission';
import AppWarning from './AppWarning';
import MessageSpinner from './MessageSpinner';
import WidgetUtils from '../../../WidgetUtils';
import dis from '../../../dispatcher';
import domtoimage from 'dom-to-image';

const ALLOWED_APP_URL_SCHEMES = ['https:', 'http:'];

export default React.createClass({
    displayName: 'AppTile',

    propTypes: {
        id: React.PropTypes.string.isRequired,
        url: React.PropTypes.string.isRequired,
        name: React.PropTypes.string.isRequired,
        room: React.PropTypes.object.isRequired,
        type: React.PropTypes.string.isRequired,
        // Specifying 'fullWidth' as true will render the app tile to fill the width of the app drawer continer.
        // This should be set to true when there is only one widget in the app drawer, otherwise it should be false.
        fullWidth: React.PropTypes.bool,
        // UserId of the current user
        userId: React.PropTypes.string.isRequired,
        // UserId of the entity that added / modified the widget
        creatorUserId: React.PropTypes.string,
        waitForIframeLoad: React.PropTypes.bool,
    },

    getDefaultProps() {
        return {
            url: "",
            waitForIframeLoad: true,
        };
    },

    /**
     * Set initial component state when the App wUrl (widget URL) is being updated.
     * Component props *must* be passed (rather than relying on this.props).
     * @param  {Object} newProps The new properties of the component
     * @return {Object} Updated component state to be set with setState
     */
    _getNewState(newProps) {
        const widgetPermissionId = [newProps.room.roomId, encodeURIComponent(newProps.url)].join('_');
        const hasPermissionToLoad = localStorage.getItem(widgetPermissionId);
        return {
            initialising: true,   // True while we are mangling the widget URL
            loading: this.props.waitForIframeLoad,        // True while the iframe content is loading
            widgetUrl: this._addWurlParams(newProps.url),
            widgetPermissionId: widgetPermissionId,
            // Assume that widget has permission to load if we are the user who
            // added it to the room, or if explicitly granted by the user
            hasPermissionToLoad: hasPermissionToLoad === 'true' || newProps.userId === newProps.creatorUserId,
            error: null,
            deleting: false,
            widgetPageTitle: newProps.widgetPageTitle,
        };
    },

    /**
     * Add widget instance specific parameters to pass in wUrl
     * Properties passed to widget instance:
     *  - widgetId
     *  - origin / parent URL
     * @param {string} urlString Url string to modify
     * @return {string}
     * Url string with parameters appended.
     * If url can not be parsed, it is returned unmodified.
     */
    _addWurlParams(urlString) {
        const u = url.parse(urlString);
        if (!u) {
            console.error("_addWurlParams", "Invalid URL", urlString);
            return url;
        }

        const params = qs.parse(u.query);
        // Append widget ID to query parameters
        params.widgetId = this.props.id;
        // Append current / parent URL
        params.parentUrl = window.location.href;
        u.search = undefined;
        u.query = params;

        return u.format();
    },

    getInitialState() {
        return this._getNewState(this.props);
    },

    /**
     * Returns true if specified url is a scalar URL, typically https://scalar.vector.im/api
     * @param  {[type]}  url URL to check
     * @return {Boolean} True if specified URL is a scalar URL
     */
    isScalarUrl(url) {
        if (!url) {
            console.error('Scalar URL check failed. No URL specified');
            return false;
        }

        let scalarUrls = SdkConfig.get().integrations_widgets_urls;
        if (!scalarUrls || scalarUrls.length == 0) {
            scalarUrls = [SdkConfig.get().integrations_rest_url];
        }

        for (let i = 0; i < scalarUrls.length; i++) {
            if (url.startsWith(scalarUrls[i])) {
                return true;
            }
        }
        return false;
    },

    isMixedContent() {
        const parentContentProtocol = window.location.protocol;
        const u = url.parse(this.props.url);
        const childContentProtocol = u.protocol;
        if (parentContentProtocol === 'https:' && childContentProtocol !== 'https:') {
            console.warn("Refusing to load mixed-content app:",
            parentContentProtocol, childContentProtocol, window.location, this.props.url);
            return true;
        }
        return false;
    },

    componentWillMount() {
        WidgetMessaging.startListening();
        WidgetMessaging.addEndpoint(this.props.id, this.props.url);
        window.addEventListener('message', this._onMessage, false);
        this.setScalarToken();
    },

    /**
     * Adds a scalar token to the widget URL, if required
     * Component initialisation is only complete when this function has resolved
     */
    setScalarToken() {
        this.setState({initialising: true});

        if (!this.isScalarUrl(this.props.url)) {
            console.warn('Non-scalar widget, not setting scalar token!', url);
            this.setState({
                error: null,
                widgetUrl: this._addWurlParams(this.props.url),
                initialising: false,
            });
            return;
        }

        // Fetch the token before loading the iframe as we need it to mangle the URL
        if (!this._scalarClient) {
            this._scalarClient = new ScalarAuthClient();
        }
        this._scalarClient.getScalarToken().done((token) => {
            // Append scalar_token as a query param if not already present
            this._scalarClient.scalarToken = token;
            const u = url.parse(this._addWurlParams(this.props.url));
            const params = qs.parse(u.query);
            if (!params.scalar_token) {
                params.scalar_token = encodeURIComponent(token);
                // u.search must be set to undefined, so that u.format() uses query paramerters - https://nodejs.org/docs/latest/api/url.html#url_url_format_url_options
                u.search = undefined;
                u.query = params;
            }

            this.setState({
                error: null,
                widgetUrl: u.format(),
                initialising: false,
            });

            // Fetch page title from remote content if not already set
            if (!this.state.widgetPageTitle && params.url) {
                this._fetchWidgetTitle(params.url);
            }
        }, (err) => {
            console.error("Failed to get scalar_token", err);
            this.setState({
                error: err.message,
                initialising: false,
            });
        });
    },

    componentWillUnmount() {
        WidgetMessaging.stopListening();
        WidgetMessaging.removeEndpoint(this.props.id, this.props.url);
        window.removeEventListener('message', this._onMessage);
    },

    componentWillReceiveProps(nextProps) {
        if (nextProps.url !== this.props.url) {
            this._getNewState(nextProps);
            this.setScalarToken();
        } else if (nextProps.show && !this.props.show && this.props.waitForIframeLoad) {
            this.setState({
                loading: true,
            });
        } else if (nextProps.widgetPageTitle !== this.props.widgetPageTitle) {
            this.setState({
                widgetPageTitle: nextProps.widgetPageTitle,
            });
        }
    },

    _onMessage(event) {
        if (this.props.type !== 'jitsi') {
            return;
        }
        if (!event.origin) {
            event.origin = event.originalEvent.origin;
        }

        if (!this.state.widgetUrl.startsWith(event.origin)) {
            return;
        }

        if (event.data.widgetAction === 'jitsi_iframe_loaded') {
            const iframe = this.refs.appFrame.contentWindow
                .document.querySelector('iframe[id^="jitsiConferenceFrame"]');
            PlatformPeg.get().setupScreenSharingForIframe(iframe);
        }
    },

    _canUserModify() {
        return WidgetUtils.canUserModifyWidgets(this.props.room.roomId);
    },

    _onEditClick(e) {
        console.log("Edit widget ID ", this.props.id);
        const IntegrationsManager = sdk.getComponent("views.settings.IntegrationsManager");
        const src = this._scalarClient.getScalarInterfaceUrlForRoom(
            this.props.room.roomId, 'type_' + this.props.type, this.props.id);
        Modal.createTrackedDialog('Integrations Manager', '', IntegrationsManager, {
            src: src,
        }, "mx_IntegrationsManager");
    },

    _onSnapshotClick(e) {
        const iframe = this.refs.appFrame;
        domtoimage.toPng(iframe).then(function(dataUrl) {
            console.log("Image data URL:", dataUrl);
            dis.dispatch({
                action: 'picture_snapshot',
                file: dataURLtoBlob(dataUrl),
            }, true);
        });
    },

    /* If user has permission to modify widgets, delete the widget,
     * otherwise revoke access for the widget to load in the user's browser
    */
    _onDeleteClick() {
        if (this._canUserModify()) {
            // Show delete confirmation dialog
            const QuestionDialog = sdk.getComponent("dialogs.QuestionDialog");
            Modal.createTrackedDialog('Delete Widget', '', QuestionDialog, {
                title: _t("Delete Widget"),
                description: _t(
                    "Deleting a widget removes it for all users in this room." +
                    " Are you sure you want to delete this widget?"),
                button: _t("Delete widget"),
                onFinished: (confirmed) => {
                    if (!confirmed) {
                        return;
                    }
                    this.setState({deleting: true});
                    MatrixClientPeg.get().sendStateEvent(
                        this.props.room.roomId,
                        'im.vector.modular.widgets',
                        {}, // empty content
                        this.props.id,
                    ).catch((e) => {
                        console.error('Failed to delete widget', e);
                        this.setState({deleting: false});
                    });
                },
            });
        } else {
            console.log("Revoke widget permissions - %s", this.props.id);
            this._revokeWidgetPermission();
        }
    },

    /**
     * Called when widget iframe has finished loading
     */
    _onLoaded() {
        this.setState({loading: false});
    },

    /**
     * Set remote content title on AppTile
     * @param {string} url Url to check for title
     */
    _fetchWidgetTitle(url) {
        this._scalarClient.getScalarPageTitle(url).then((widgetPageTitle) => {
            if (widgetPageTitle) {
                this.setState({widgetPageTitle: widgetPageTitle});
            }
        }, (err) =>{
            console.error("Failed to get page title", err);
        });
    },

    // Widget labels to render, depending upon user permissions
    // These strings are translated at the point that they are inserted in to the DOM, in the render method
    _deleteWidgetLabel() {
        if (this._canUserModify()) {
            return _td('Delete widget');
        }
        return _td('Revoke widget access');
    },

    /* TODO -- Store permission in account data so that it is persisted across multiple devices */
    _grantWidgetPermission() {
        console.warn('Granting permission to load widget - ', this.state.widgetUrl);
        localStorage.setItem(this.state.widgetPermissionId, true);
        this.setState({hasPermissionToLoad: true});
    },

    _revokeWidgetPermission() {
        console.warn('Revoking permission to load widget - ', this.state.widgetUrl);
        localStorage.removeItem(this.state.widgetPermissionId);
        this.setState({hasPermissionToLoad: false});
    },

    formatAppTileName() {
        let appTileName = "No name";
        if (this.props.name && this.props.name.trim()) {
            appTileName = this.props.name.trim();
        }
        return appTileName;
    },

    onClickMenuBar(ev) {
        ev.preventDefault();

        // Ignore clicks on menu bar children
        if (ev.target !== this.refs.menu_bar) {
            return;
        }

        // Toggle the view state of the apps drawer
        dis.dispatch({
            action: 'appsDrawer',
            show: !this.props.show,
        });
    },

    _getSafeUrl() {
        const parsedWidgetUrl = url.parse(this.state.widgetUrl);
        let safeWidgetUrl = '';
        if (ALLOWED_APP_URL_SCHEMES.indexOf(parsedWidgetUrl.protocol) !== -1) {
            safeWidgetUrl = url.format(parsedWidgetUrl);
        }
        return safeWidgetUrl;
    },

    render() {
        let appTileBody;

        // Don't render widget if it is in the process of being deleted
        if (this.state.deleting) {
            return <div></div>;
        }

        // Note that there is advice saying allow-scripts shouldn't be used with allow-same-origin
        // because that would allow the iframe to prgramatically remove the sandbox attribute, but
        // this would only be for content hosted on the same origin as the riot client: anything
        // hosted on the same origin as the client will get the same access as if you clicked
        // a link to it.
        const sandboxFlags = "allow-forms allow-popups allow-popups-to-escape-sandbox "+
            "allow-same-origin allow-scripts allow-presentation";

        if (this.props.show) {
            const loadingElement = (
                <div className='mx_AppTileBody mx_AppLoading'>
                    <MessageSpinner msg='Loading...' />
                </div>
            );
            if (this.state.initialising) {
                appTileBody = loadingElement;
            } else if (this.state.hasPermissionToLoad == true) {
                if (this.isMixedContent()) {
                    appTileBody = (
                        <div className="mx_AppTileBody">
                            <AppWarning errorMsg="Error - Mixed content" />
                        </div>
                    );
                } else {
                    appTileBody = (
                        <div className={this.state.loading ? 'mx_AppTileBody mx_AppLoading' : 'mx_AppTileBody'}>
                            { this.state.loading && loadingElement }
                            <iframe
                                ref="appFrame"
                                src={this._getSafeUrl()}
                                allowFullScreen="true"
                                sandbox={sandboxFlags}
                                onLoad={this._onLoaded}
                            ></iframe>
                        </div>
                    );
                }
            } else {
                const isRoomEncrypted = MatrixClientPeg.get().isRoomEncrypted(this.props.room.roomId);
                appTileBody = (
                    <div className="mx_AppTileBody">
                        <AppPermission
                            isRoomEncrypted={isRoomEncrypted}
                            url={this.state.widgetUrl}
                            onPermissionGranted={this._grantWidgetPermission}
                        />
                    </div>
                );
            }
        }

        // editing is done in scalar
        const showEditButton = Boolean(this._scalarClient && this._canUserModify());
        const deleteWidgetLabel = this._deleteWidgetLabel();
        let deleteIcon = 'img/cancel_green.svg';
        let deleteClasses = 'mx_AppTileMenuBarWidget';
        if (this._canUserModify()) {
            deleteIcon = 'img/icon-delete-pink.svg';
            deleteClasses += ' mx_AppTileMenuBarWidgetDelete';
        }

        // Picture snapshot
        const showPictureSnapshotButton = true; // FIXME - Make this dynamic
        const showPictureSnapshotIcon = 'img/camera_green.svg';
        const windowStateIcon = (this.props.show ? 'img/minimize.svg' : 'img/maximize.svg');

        return (
            <div className={this.props.fullWidth ? "mx_AppTileFullWidth" : "mx_AppTile"} id={this.props.id}>
                <div ref="menu_bar" className="mx_AppTileMenuBar" onClick={this.onClickMenuBar}>
                    <span className="mx_AppTileMenuBarTitle">
                        <TintableSvgButton
                            src={windowStateIcon}
                            className="mx_AppTileMenuBarWidget mx_AppTileMenuBarWidgetPadding"
                            title={_t('Minimize apps')}
                            width="10"
                            height="10"
                        />
                        <b>{ this.formatAppTileName() }</b>
                        { this.state.widgetPageTitle && this.state.widgetPageTitle != this.formatAppTileName() && (
                            <span>&nbsp;-&nbsp;{ this.state.widgetPageTitle }</span>
                        ) }
                    </span>
                    <span className="mx_AppTileMenuBarWidgets">
                      { /* Snapshot widget */ }
                      { showPictureSnapshotButton && <TintableSvgButton
                          src={showPictureSnapshotIcon}
                          className="mx_AppTileMenuBarWidget mx_AppTileMenuBarWidgetPadding"
                          title={_t('Picture')}
                          onClick={this._onSnapshotClick}
                          width="10"
                          height="10"
                      /> }

                        { /* Edit widget */ }
                        { showEditButton && <TintableSvgButton
                            src="img/edit_green.svg"
                            className="mx_AppTileMenuBarWidget mx_AppTileMenuBarWidgetPadding"
                            title={_t('Edit')}
                            onClick={this._onEditClick}
                            width="10"
                            height="10"
                        /> }

                        { /* Delete widget */ }
                        <TintableSvgButton
                            src={deleteIcon}
                            className={deleteClasses}
                            title={_t(deleteWidgetLabel)}
                            onClick={this._onDeleteClick}
                            width="10"
                            height="10"
                        />
                    </span>
                </div>
                { appTileBody }
            </div>
        );
    },
});

function dataURLtoBlob(dataurl) {
    const arr = dataurl.split(',');
    const mime = arr[0].match(/:(.*?);/)[1];
    const bstr = atob(arr[1]);
    let n = bstr.length;
    const u8arr = new Uint8Array(n);
    while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
    }
    return new Blob([u8arr], {type: mime});
}