//
// Copyright (C) Stanislaw Adaszewski, 2020
// Contact: s.adaszewski@gmail.com
// Website: https://adared.ch/wba
// License: GNU Affero General Public License, Version 3
//

import { h, Component } from 'preact';
import WBTable from 'wb-table';
import WBBreadcrumbs from 'wb-breadcrumbs';
import WBPagination from 'wb-pagination';
import makeArvadosRequest from 'make-arvados-request';
import wbDownloadFile from 'wb-download-file';
import WBManifestWorkerWrapper from 'wb-manifest-worker-wrapper';

function unescapeName(name) {
  return name.replace(/(\\\\|\\[0-9]{3})/g,
    (_, $1) => ($1 === '\\\\' ? '\\' : String.fromCharCode(parseInt($1.substr(1), 8))));
}

function encodeURIComponentIncludingDots(s) {
  return encodeURIComponent(s).replace('.', '%2E');
}

function endsWith(what, endings) {
  if (typeof(endings) === 'string')
    return what.endsWith(endings);
  if (endings instanceof Array)
    return endings.map(a => what.endsWith(a)).reduce((a, b) => (a || b));
  throw Error('Expected second argument to be either a string or an array');
}

function maskRows(rows) {
  return rows.map(r => r.map(c => '-'));
}

class WBCollectionContent extends Component {
  constructor(...args) {
    super(...args);
    this.state.rows = [];
    this.state.manifestWorker = new WBManifestWorkerWrapper();
    this.state.loaded = 0;
    this.state.total = 0;
    this.state.mode = 'manifestDownload';
    this.state.parsedStreams = 0;
    this.state.totalStreams = 1;
  }

  getUrl(params) {
    let res = '/collection-browse/' +
      ('uuid' in params ? params.uuid : this.props.uuid) + '/' +
      encodeURIComponentIncludingDots('collectionPath' in params ? params.collectionPath : this.props.collectionPath) + '/' +
      ('page' in params ? params.page : this.props.page);
    return res;
  }

  componentDidMount() {
    let { arvHost, arvToken } = this.props.app.state;
    let { uuid, collectionPath } = this.props;
    let { manifestWorker } = this.state;

    let select = [ 'manifest_text' ];
    let prom = makeArvadosRequest(arvHost, arvToken,
      '/arvados/v1/collections/' + uuid +
      '?select=' + encodeURIComponent(JSON.stringify(select)),
      { 'onProgress': e => {
        this.setState({ 'loaded': e.loaded, 'total': e.total });
      } });

    prom = prom.then(xhr => {
      const streams = xhr.response.manifest_text.split('\n');
      const paths = streams.filter(s => s).map(s => {
        const n = s.indexOf(' ');
        return unescapeName(s.substr(0, n));
      });

      let prom_1 = new Promise(accept => accept());

      prom_1 = prom_1.then(() => {
        this.setState({
          'totalStreams': streams.length,
          'parsedStreams': 0,
          'mode': 'manifestParse'
        });
        return manifestWorker.postMessage([ 'precreatePaths', paths ]);
      });

      let lastListingTimestamp = new Date(0);

      for (let i = 0; i < streams.length; i++) {
        prom_1 = prom_1.then(() => manifestWorker.postMessage([ 'parseStream', streams[i] ]));

        prom_1 = prom_1.then(() => {
          if (new Date() - lastListingTimestamp < 1000)
            return;

          lastListingTimestamp = new Date();

          let prom_2 = new Promise(accept => accept());

          prom_2 = prom_2.then(() => manifestWorker.postMessage([
            'listDirectory', '.' + this.props.collectionPath, true
          ]));

          prom_2 = prom_2.then(e => {
            this.prepareRows(e.data[1]);
            this.setState({ 'parsedStreams': (i + 1) });
          });

          return prom_2;
        });
      }

      prom_1 = prom_1.then(() => manifestWorker.postMessage([ 'listDirectory',
        '.' + this.props.collectionPath, true ]));

      prom_1 = prom_1.then(e => {
        this.state.mode = 'browsingReady';
        this.prepareRows(e.data[1]);
      });

      return prom_1;
    });
  }

  componentWillReceiveProps(nextProps) {
    this.props = nextProps;

    this.setState({ rows: maskRows(this.state.rows) });

    const { manifestWorker, mode } = this.state;
    const { collectionPath } = this.props;

    if (mode === 'browsingReady') {
      let prom = manifestWorker.postMessage([ 'listDirectory', '.' + collectionPath, true ]);
      prom = prom.then(e => this.prepareRows(e.data[1]));
    }
  }

  prepareRows(listing) {
    let { manifestWorker, mode } = this.state;
    let { collectionPath, page, itemsPerPage, app } = this.props;
    let { arvHost, arvToken } = app.state;

    const numPages = Math.ceil(listing.length / itemsPerPage);
    listing = listing.slice(page * itemsPerPage,
      page * itemsPerPage + itemsPerPage);

    this.setState({
      'numPages': numPages,
      'rows': listing.map(item => (
        (item[0] === 'd') ? [
          (<a href={ this.getUrl({ 'collectionPath': collectionPath + '/' + item[1], 'page': 0 }) }>{ item[1] }/</a>),
          'Directory',
          null,
          (<div></div>)
        ] : [
          item[1],
          'File',
          filesize(item[2]),
          ( (mode === 'browsingReady') ? (
            <div>
              <button class="btn btn-outline-primary mx-1" title="Download"
                onclick={ () => manifestWorker.postMessage([ 'getFile',
                    '.' + collectionPath + '/' + item[1] ]).then(e => {
                      const file = e.data[1];
                      const blob = new Blob([
                        JSON.stringify([ arvHost, arvToken, item[1], file ])
                      ]);
                      const blocksBlobUrl = URL.createObjectURL(blob);
                      window.open('/download/' + encodeURIComponent(blocksBlobUrl), '_blank');

                    }) }><i class="fas fa-download"></i></button>

              <button class="btn btn-outline-primary mx-1" title="View"
                onclick={ () => {
                  alert('Not implemented.')
                } }><i class="far fa-eye"></i></button>

              { endsWith(item[1].toLowerCase(), ['.nii', '.nii.gz']) ? (
                <button class="btn btn-outline-primary mx-1" title="View Image"
                  onclick={ () => manifestWorker.postMessage([ 'getFile',
                      '.' + collectionPath + '/' + item[1] ]).then(e => {
                      const file = e.data[1];
                      const blob = new Blob([
                        JSON.stringify({ 'name': item[1], 'file': file })
                      ]);
                      const blocksBlobUrl = URL.createObjectURL(blob);
                      window.open('/image-viewer/' + encodeURIComponent(blocksBlobUrl), '_blank');

                    }) }><i class="fas fa-image"></i></button>
              ) : null }
            </div>
          ) : null)
        ]
      ))
    });
  }

  render({ collectionPath, page }, { manifestReader, rows,
    numPages, loaded, total, mode, parsedStreams, totalStreams }) {

    return (
      <div>
        <WBBreadcrumbs items={ ('.' + collectionPath).split('/').map((name, index) => ({ name, index })) }
          getItemUrl={ it => this.getUrl({
            collectionPath: ('.' + collectionPath).split('/').slice(0, it.index + 1).join('/').substr(1),
            page: 0
          }) } />

        { (mode === 'manifestDownload') ?
          (
            <div class="container-fluid">
              <div>Downloading manifest: { filesize(loaded) }</div>
              <div class="progress">
                <div class="progress-bar progress-bar-striped progress-bar-animated" role="progressbar"
                  aria-valuenow="100" aria-valuemin="0" aria-valuemax="100" style="width: 100%"></div>
              </div>
            </div>

          ) : (
            <div>
              { mode === 'manifestParse' ? (
                <div class="container-fluid mb-2">
                  <div>Parsing manifest: { parsedStreams }/{ totalStreams }</div>
                  <div class="progress">
                    <div class="progress-bar progress-bar-striped progress-bar-animated bg-success" role="progressbar"
                      aria-valuenow={ totalStreams } aria-valuemin="0" aria-valuemax={ parsedStreams } style={ 'width: ' + Math.round(parsedStreams * 100 / totalStreams) + '%' }></div>
                  </div>
                </div>
              ) : null }

              <WBTable columns={ [ 'Name', 'Type', 'Size', 'Actions' ] }
                rows={ rows } />

              <WBPagination activePage={ page } numPages={ numPages }
                getPageUrl={ page => this.getUrl({ 'page': page }) } />
            </div>
          ) }
      </div>
    );
  }
}

WBCollectionContent.defaultProps = {
  'collectionPath': '',
  'page': 0,
  'itemsPerPage': 20
};

export default WBCollectionContent;