import 'package:flutter/material.dart';
import '../api/client.dart';
import '../api/models.dart';
import '../widgets/pipeline_card.dart';
import 'pipeline_editor.dart';
import 'pipeline_detail.dart';

class PipelineListScreen extends StatefulWidget {
  const PipelineListScreen({super.key});

  @override
  State<PipelineListScreen> createState() => _PipelineListScreenState();
}

class _PipelineListScreenState extends State<PipelineListScreen> {
  late APIClient _api;
  List<Pipeline> _pipelines = [];
  bool _loading = true;
  String? _error;

  @override
  void initState() {
    super.initState();
    final url = _parseBaseUrl();
    _api = APIClient(baseUrl: url);
    _load();
  }

  static String _parseBaseUrl() {
    final uri = Uri.base;
    return '${uri.scheme}://${uri.host}${uri.port != 80 && uri.port != 443 ? ':${uri.port}' : ''}';
  }

  Future<void> _load() async {
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final pipelines = await _api.listPipelines();
      setState(() {
        _pipelines = pipelines;
        _loading = false;
      });
    } catch (e) {
      setState(() {
        _error = e.toString();
        _loading = false;
      });
    }
  }

  Future<void> _createPipeline() async {
    final result = await Navigator.push<Pipeline>(
      context,
      MaterialPageRoute(builder: (_) => const PipelineEditorScreen()),
    );
    if (result != null) {
      _pipelines.add(result);
      setState(() {});
    }
  }

  void _navigateToDetail(Pipeline p) {
    Navigator.push(
      context,
      MaterialPageRoute(builder: (_) => PipelineDetailScreen(pipeline: p)),
    );
  }

  Future<void> _deletePipeline(Pipeline p) async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Delete Pipeline'),
        content: Text('Are you sure you want to delete "${p.name}"?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: const Text('Cancel'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(ctx, true),
            child: const Text('Delete'),
          ),
        ],
      ),
    );
    if (confirmed != true) return;

    try {
      await _api.deletePipeline(p.id);
      setState(() {
        _pipelines.removeWhere((pl) => pl.id == p.id);
      });
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text(e.toString())));
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Zaloopipe'),
        actions: [
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: _load,
            tooltip: 'Refresh',
          ),
        ],
      ),
      body: _loading
          ? const Center(child: CircularProgressIndicator())
          : _error != null
          ? Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  const Icon(Icons.error_outline, size: 48, color: Colors.red),
                  const SizedBox(height: 16),
                  Text(_error!, textAlign: TextAlign.center),
                  const SizedBox(height: 16),
                  FilledButton(onPressed: _load, child: const Text('Retry')),
                ],
              ),
            )
          : _pipelines.isEmpty
          ? Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  const Icon(Icons.api_outlined, size: 64, color: Colors.grey),
                  const SizedBox(height: 16),
                  const Text(
                    'No pipelines yet',
                    style: TextStyle(fontSize: 18, color: Colors.grey),
                  ),
                  const SizedBox(height: 8),
                  FilledButton.icon(
                    onPressed: _createPipeline,
                    icon: const Icon(Icons.add),
                    label: const Text('Create Pipeline'),
                  ),
                ],
              ),
            )
          : RefreshIndicator(
              onRefresh: _load,
              child: ListView.builder(
                itemCount: _pipelines.length + 1,
                padding: const EdgeInsets.symmetric(vertical: 8),
                itemBuilder: (ctx, i) {
                  if (i == _pipelines.length) {
                    return Padding(
                      padding: const EdgeInsets.all(16),
                      child: SizedBox(
                        height: 48,
                        width: double.infinity,
                        child: FilledButton.icon(
                          onPressed: _createPipeline,
                          icon: const Icon(Icons.add),
                          label: const Text('Create Pipeline'),
                        ),
                      ),
                    );
                  }
                  final p = _pipelines[i];
                  return PipelineCard(
                    pipeline: p,
                    onTap: () => _navigateToDetail(p),
                    onDelete: () => _deletePipeline(p),
                  );
                },
              ),
            ),
    );
  }
}