/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 *
 * Any modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

/*
 * Licensed to Elasticsearch B.V. under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. licenses this file to you 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 { EuiLoadingSpinner, EuiProgress } from '@elastic/eui';
import { i18n } from '@osd/i18n';
import React from 'react';
import classNames from 'classnames';
import { Subscription } from 'rxjs';

import { HttpStart } from '../../http';

export interface LoadingIndicatorProps {
  loadingCount$: ReturnType<HttpStart['getLoadingCount$']>;
  showAsBar?: boolean;
}

export class LoadingIndicator extends React.Component<LoadingIndicatorProps, { visible: boolean }> {
  public static defaultProps = { showAsBar: false };

  private loadingCountSubscription?: Subscription;

  state = {
    visible: false,
  };

  componentDidMount() {
    this.loadingCountSubscription = this.props.loadingCount$.subscribe((count) => {
      this.setState({
        visible: count > 0,
      });
    });
  }

  componentWillUnmount() {
    if (this.loadingCountSubscription) {
      this.loadingCountSubscription.unsubscribe();
      this.loadingCountSubscription = undefined;
    }
  }

  render() {
    const className = classNames(!this.state.visible && 'osdLoadingIndicator-hidden');

    const testSubj = this.state.visible
      ? 'globalLoadingIndicator'
      : 'globalLoadingIndicator-hidden';

    const ariaHidden = this.state.visible ? false : true;

    const ariaLabel = i18n.translate('core.ui.loadingIndicatorAriaLabel', {
      defaultMessage: 'Loading content',
    });

    return !this.props.showAsBar ? (
      <EuiLoadingSpinner
        className={className}
        data-test-subj={testSubj}
        aria-hidden={ariaHidden}
        aria-label={ariaLabel}
      />
    ) : (
      <EuiProgress
        className={className}
        data-test-subj={testSubj}
        aria-hidden={ariaHidden}
        aria-label={ariaLabel}
        position="fixed"
        color="accent"
        size="xs"
      />
    );
  }
}