element-web/src/components/structures/TabbedView.tsx

/*
Copyright 2017 Travis Ralston
Copyright 2019 New Vector Ltd
Copyright 2019, 2020 The Matrix.org Foundation C.I.C.

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 * as React from "react";
import {_t} from '../../languageHandler';
import * as PropTypes from "prop-types";
import * as sdk from "../../index";
import { ReactNode } from "react";

/**
 * Represents a tab for the TabbedView.
 */
export class Tab {
    public label: string;
    public icon: string;
    public body: React.ReactNode;

    /**
     * Creates a new tab.
     * @param {string} tabLabel The untranslated tab label.
     * @param {string} tabIconClass The class for the tab icon. This should be a simple mask.
     * @param {React.ReactNode} tabJsx The JSX for the tab container.
     */
    constructor(tabLabel: string, tabIconClass: string, tabJsx: React.ReactNode) {
        this.label = tabLabel;
        this.icon = tabIconClass;
        this.body = tabJsx;
    }
}

interface IProps {
    tabs: Tab[];
}

interface IState {
    activeTabIndex: number;
}

export default class TabbedView extends React.Component<IProps, IState> {
    static propTypes = {
        // The tabs to show
        tabs: PropTypes.arrayOf(PropTypes.instanceOf(Tab)).isRequired,
    };

    constructor(props: IProps) {
        super(props);

        this.state = {
            activeTabIndex: 0,
        };
    }

    private _getActiveTabIndex() {
        if (!this.state || !this.state.activeTabIndex) return 0;
        return this.state.activeTabIndex;
    }

    /**
     * Shows the given tab
     * @param {Tab} tab the tab to show
     * @private
     */
    private _setActiveTab(tab: Tab) {
        const idx = this.props.tabs.indexOf(tab);
        if (idx !== -1) {
            this.setState({activeTabIndex: idx});
        } else {
            console.error("Could not find tab " + tab.label + " in tabs");
        }
    }

    private _renderTabLabel(tab: Tab) {
        const AccessibleButton = sdk.getComponent('elements.AccessibleButton');

        let classes = "mx_TabbedView_tabLabel ";

        const idx = this.props.tabs.indexOf(tab);
        if (idx === this._getActiveTabIndex()) classes += "mx_TabbedView_tabLabel_active";

        let tabIcon = null;
        if (tab.icon) {
            tabIcon = <span className={`mx_TabbedView_maskedIcon ${tab.icon}`} />;
        }

        const onClickHandler = () => this._setActiveTab(tab);

        const label = _t(tab.label);
        return (
            <AccessibleButton className={classes} key={"tab_label_" + tab.label} onClick={onClickHandler}>
                {tabIcon}
                <span className="mx_TabbedView_tabLabel_text">
                    { label }
                </span>
            </AccessibleButton>
        );
    }

    private _renderTabPanel(tab: Tab): React.ReactNode {
        return (
            <div className="mx_TabbedView_tabPanel" key={"mx_tabpanel_" + tab.label}>
                <div className='mx_TabbedView_tabPanelContent'>
                    {tab.body}
                </div>
            </div>
        );
    }

    public render(): React.ReactNode {
        const labels = this.props.tabs.map(tab => this._renderTabLabel(tab));
        const panel = this._renderTabPanel(this.props.tabs[this._getActiveTabIndex()]);

        return (
            <div className="mx_TabbedView">
                <div className="mx_TabbedView_tabLabels">
                    {labels}
                </div>
                {panel}
            </div>
        );
    }
}