import '../../database/database.dart';
import '../../l10n/strings.dart';
import '../../mews/document.dart';
import 'mews_urls.dart';
import 'page_blocks.dart';

/// Every text the reader kept from a page, with the page it came from. The
/// page mirrors the posts page: a searchable list ordered by the day the
/// text was kept or by the page it came from, one row per quotation, each
/// row carrying the citation's author when the page named one.
Future<MewsPage> buildQuotationsPage(
  Uri url, {
  required MewsDatabase db,
  required Strings strings,
}) async {
  final query = url.queryParameters['q'] ?? '';
  final sort = QuotationSort.parse(url.queryParameters['sort']);
  final quotations = await db.quotationsList(sort: sort, query: query);
  final total = await db.countQuotations();
  final title = strings.t('quotations-title');

  return internalPage(
    url: url,
    title: title,
    strings: strings,
    body: [
      ...chrome(title: title, current: url, strings: strings),
      textForm(
        action: MewsUrls.quotations,
        label: strings.t('quotations-search-label'),
        submitLabel: strings.t('action-search'),
        field: 'q',
        value: query,
      ),
      ...linkLine([
        if (query.isNotEmpty)
          action(MewsUrls.page(url, {'q': null}),
              strings.t('action-clear-search')),
      ]),
      ...choiceLine(
        label: strings.t('posts-sort-label'),
        options: [
          for (final option in const [
            (QuotationSort.date, 'posts-sort-date'),
            (QuotationSort.page, 'quotations-sort-page'),
          ])
            (
              href: MewsUrls.page(url, {'sort': option.$1.name}),
              label: strings.t(option.$2),
              current: option.$1 == sort,
            ),
        ],
      ),
      const RuleBlock(),
      ParagraphBlock([
        MewsEmphasis(EmphasisStyle.emphasis, [
          MewsText(countText(strings, total,
              none: 'count-quotations-none',
              one: 'count-quotations-one',
              many: 'count-quotations-many')),
        ]),
      ]),
      if (quotations.isEmpty)
        ParagraphBlock([
          MewsText(strings.t(
              query.isEmpty ? 'quotations-empty' : 'quotations-no-matches')),
        ])
      else
        itemList([
          for (final quotation in quotations)
            itemRow(
              href: quotation.pageUrl,
              label: quotation.quote,
              date: dayText(quotation.createdAt),
              // The row names the page the text came from, not just the
              // text: the author and the article's title when they are
              // known, and the site by its own title when the reader's
              // subscriptions know it, otherwise by its host.
              note: _rowNote(quotation),
              actions: [
                action(
                    MewsUrls.action('share-quotation', {'id': '${quotation.id}'}),
                    strings.t('quotations-share')),
                action(
                    MewsUrls.action(
                        'remove-quotation', {'id': '${quotation.id}'}),
                    strings.t('quotations-remove')),
              ],
            ),
        ]),
    ],
  );
}

/// Who and what the row names behind a quotation: the author and the
/// article's title when they are known, and the site the page came from by
/// its own title, or by its host when the subscriptions do not know it.
/// Nothing is named twice.
String? _rowNote(Quotation quotation) {
  final host = Uri.tryParse(quotation.pageUrl)?.host;
  final source = (quotation.siteTitle?.trim().isNotEmpty ?? false)
      ? quotation.siteTitle!.trim()
      : (host != null && host.isNotEmpty ? host : quotation.pageUrl);
  final named = <String>{};
  final parts = [
    for (final part in [
      quotation.author?.trim(),
      quotation.pageTitle?.trim(),
      source,
    ])
      if (part != null && part.isNotEmpty && named.add(part)) part,
  ];
  return parts.isEmpty ? null : parts.join(actionSeparator);
}

/// The citation a quotation travels with, shaped as APA names a web page:
/// the author first when the page's metadata carried one, otherwise the
/// article's title; the year as a no-date marker, since a page declares no
/// publication date; then the article's title, the site's own title and the
/// address. The site is named by its title when the reader's subscriptions
/// know it, and by its host when they do not; nothing is named twice.
String citationFor(Quotation quotation, Strings strings) {
  final noDate = strings.t('quotations-no-date');
  final uri = Uri.tryParse(quotation.pageUrl);
  final host =
      uri != null && uri.host.isNotEmpty ? uri.host : quotation.pageUrl;
  final author = quotation.author?.trim();
  final title = quotation.pageTitle?.trim();
  final site = (quotation.siteTitle?.trim().isNotEmpty ?? false)
      ? quotation.siteTitle!.trim()
      : host;
  final lead = (author != null && author.isNotEmpty) ? author : title ?? site;
  final named = [
    if (lead != title && title != null && title.isNotEmpty) title,
    if (site != lead && site != title) site,
  ];
  if (named.isEmpty) return '$lead ($noDate). ${quotation.pageUrl}.';
  return '$lead ($noDate). ${named.join('. ')}. ${quotation.pageUrl}.';
}