Tricoder/frontend/lib/features/experiment/presentation/pages/experiment_page.dart

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../../../services/analysis_providers.dart';
import '../../../shared/presentation/widgets/async_value_view.dart';
import '../../../shared/presentation/widgets/lab_section_scaffold.dart';

class ExperimentPage extends ConsumerWidget {
  const ExperimentPage({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final theme = Theme.of(context);
    final snapshot = ref.watch(selectedSessionSnapshotProvider);

    return LabSectionScaffold(
      eyebrow: 'Experiment',
      title: 'Follow the AI analyst through each validation step.',
      description:
          'This page visualizes hypotheses, validation chains, score changes, and structured failure reasons across the experiment timeline.',
      children: [
        AsyncValueView(
          value: snapshot,
          loadingMessage: 'Loading experiment timeline...',
          data: (session) {
            if (session == null) {
              return const _EmptySessionCard();
            }

            return Column(
              children: [
                Card(
                  child: Padding(
                    padding: const EdgeInsets.all(20),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text('Hypotheses', style: theme.textTheme.titleLarge),
                        const SizedBox(height: 12),
                        ...session.hypotheses.map(
                          (hypothesis) => Padding(
                            padding: const EdgeInsets.only(bottom: 14),
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.start,
                              children: [
                                Text(
                                  '${hypothesis.label} | ${hypothesis.confidence.toStringAsFixed(2)}',
                                  style: theme.textTheme.titleMedium,
                                ),
                                const SizedBox(height: 4),
                                Text(
                                  hypothesis.rationale,
                                  style: theme.textTheme.bodyMedium,
                                ),
                                const SizedBox(height: 6),
                                Wrap(
                                  spacing: 8,
                                  runSpacing: 8,
                                  children: hypothesis.relatedSignalProfiles
                                      .map((item) => Chip(label: Text(item)))
                                      .toList(),
                                ),
                              ],
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
                const SizedBox(height: 16),
                ...session.experiments.map(
                  (experiment) => Card(
                    child: Padding(
                      padding: const EdgeInsets.all(20),
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(
                            experiment.title,
                            style: theme.textTheme.titleLarge,
                          ),
                          const SizedBox(height: 8),
                          Text(
                            'Status: ${experiment.status} | Score: ${experiment.score.total.toStringAsFixed(2)}',
                            style: theme.textTheme.bodyMedium,
                          ),
                          if (experiment.hypothesisId != null) ...[
                            const SizedBox(height: 6),
                            Text(
                              'Hypothesis: ${experiment.hypothesisId}',
                              style: theme.textTheme.bodyMedium,
                            ),
                          ],
                          const SizedBox(height: 12),
                          ...experiment.pipelineSummary.map(
                            (node) => Padding(
                              padding: const EdgeInsets.only(bottom: 4),
                              child: Text('- $node'),
                            ),
                          ),
                          if (experiment.score.notes.isNotEmpty) ...[
                            const SizedBox(height: 12),
                            ...experiment.score.notes.map(
                              (note) => Text('Note: $note'),
                            ),
                          ],
                          if (experiment.failureReasons.isNotEmpty) ...[
                            const SizedBox(height: 12),
                            Text(
                              'Failure reasons: ${experiment.failureReasons.join(', ')}',
                              style: theme.textTheme.bodyMedium,
                            ),
                          ],
                        ],
                      ),
                    ),
                  ),
                ),
                const SizedBox(height: 8),
                FilledButton(
                  onPressed: () => context.goNamed('conclusion'),
                  child: const Text('Review Conclusion'),
                ),
              ],
            );
          },
        ),
      ],
    );
  }
}

class _EmptySessionCard extends StatelessWidget {
  const _EmptySessionCard();

  @override
  Widget build(BuildContext context) {
    return const Card(
      child: Padding(
        padding: EdgeInsets.all(20),
        child: Text('No session selected yet.'),
      ),
    );
  }
}