import 'package:flutter/material.dart';

import '../../core/region/region_config.dart';
import '../../l10n/app_localizations.dart';
import '../sources/sources_screen.dart';

/// Always-visible credits for whatever is currently drawn on the map.
///
/// This is a licence obligation, not decoration: OpenStreetMap's ODbL and
/// Radar-DPC's CC BY-SA both require the credit to be shown wherever the data
/// is. It is therefore never collapsed, hidden behind a gesture, or covered by
/// another control, and it lists only the sources actually on screen — crediting
/// OpenStreetMap while showing the offline fallback would be a false claim.
class AttributionBar extends StatelessWidget {
  const AttributionBar({
    required this.region,
    required this.activeSourceIds,
    this.additionalCredits = const <String>[],
    this.showBaseMapNotice = false,
    super.key,
  });

  final RegionConfig region;

  /// Attribution ids, matching `attributions[].id` in the region config, for
  /// the data currently rendered.
  final Set<String> activeSourceIds;

  /// Credits that travel with the data rather than with the region, such as the
  /// attribution line inside a radar manifest. Whoever published those frames
  /// states there who to credit for them, which is more current than anything
  /// baked into the app.
  final List<String> additionalCredits;

  /// Whether to say that no base map is configured. True when the offline
  /// fallback style is in use, so the placeholder is never mistaken for a map.
  final bool showBaseMapNotice;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final theme = Theme.of(context);

    final credits = region.attributions
        .where((attribution) => activeSourceIds.contains(attribution.id))
        .map((attribution) => attribution.text)
        .toList(growable: false);

    final parts = <String>[
      if (showBaseMapNotice) l10n.baseMapNotConfigured,
      ...credits,
      ...additionalCredits.where((credit) => credit.isNotEmpty),
    ];

    return Material(
      color: theme.colorScheme.surface.withValues(alpha: 0.85),
      child: InkWell(
        onTap: () => Navigator.of(
          context,
        ).push(MaterialPageRoute<void>(builder: (_) => const SourcesScreen())),
        child: Padding(
          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
          child: Row(
            children: [
              Expanded(
                child: Text(
                  parts.join(' · '),
                  style: theme.textTheme.bodySmall,
                  maxLines: 2,
                  overflow: TextOverflow.ellipsis,
                ),
              ),
              const SizedBox(width: 8),
              Text(
                l10n.sourcesLink,
                style: theme.textTheme.bodySmall?.copyWith(
                  color: theme.colorScheme.primary,
                  fontWeight: FontWeight.w600,
                ),
              ),
              Icon(
                Icons.chevron_right,
                size: 16,
                color: theme.colorScheme.primary,
              ),
            ],
          ),
        ),
      ),
    );
  }
}