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

import '../../core/exceptions.dart';
import '../../providers/api_client_provider.dart';
import '../../providers/notes_provider.dart';
import '../../providers/tasks_provider.dart';

class QuickCaptureScreen extends ConsumerStatefulWidget {
  const QuickCaptureScreen({super.key});

  @override
  ConsumerState<QuickCaptureScreen> createState() =>
      _QuickCaptureScreenState();
}

class _QuickCaptureScreenState extends ConsumerState<QuickCaptureScreen> {
  final _controller = TextEditingController();
  final _focusNode = FocusNode();
  bool _loading = false;

  @override
  void dispose() {
    _controller.dispose();
    _focusNode.dispose();
    super.dispose();
  }

  Future<void> _send() async {
    final text = _controller.text.trim();
    if (text.isEmpty) return;
    setState(() => _loading = true);
    try {
      final result =
          await ref.read(quickCaptureApiProvider).capture(text);
      // Invalidate the relevant provider so the list screen re-fetches.
      switch (result.type) {
        case 'note':
          ref.invalidate(notesProvider);
        case 'task':
        case 'todo':
          ref.invalidate(tasksProvider);
      }

      if (mounted) {
        // Use the server's human-readable message if available, else compose one.
        final msg = result.message.isNotEmpty
            ? result.message
            : '${_typeLabel(result.type)} created: ${result.title}';
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(msg),
            behavior: SnackBarBehavior.floating,
          ),
        );
        context.pop();
      }
    } on AppException catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(e.message),
            behavior: SnackBarBehavior.floating,
          ),
        );
      }
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  String _typeLabel(String type) => switch (type) {
        'note' => 'Note',
        'task' => 'Task',
        'event' => 'Event',
        'todo' => 'To-do',
        _ => type,
      };

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

    return Scaffold(
      appBar: AppBar(title: const Text('Quick Capture')),
      body: Padding(
        padding: const EdgeInsets.all(20),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Text(
              'What\'s on your mind?',
              style: theme.textTheme.titleMedium,
            ),
            const SizedBox(height: 4),
            Text(
              'Describe a note, task, event, or research item — Fabled will figure out the rest.',
              style: theme.textTheme.bodySmall?.copyWith(
                color: theme.colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: 16),
            TextField(
              controller: _controller,
              focusNode: _focusNode,
              autofocus: true,
              enabled: !_loading,
              maxLines: 6,
              minLines: 3,
              keyboardType: TextInputType.multiline,
              decoration: InputDecoration(
                hintText:
                    'e.g. "Remind me to call the dentist next Monday" or "Note: project meeting went well, key points were..."',
                border: const OutlineInputBorder(),
                alignLabelWithHint: true,
                suffixIcon: _controller.text.isNotEmpty
                    ? IconButton(
                        icon: const Icon(Icons.clear),
                        onPressed: () {
                          _controller.clear();
                          setState(() {});
                        },
                      )
                    : null,
              ),
              onChanged: (_) => setState(() {}),
            ),
            const SizedBox(height: 16),
            FilledButton.icon(
              onPressed: (_loading || _controller.text.trim().isEmpty)
                  ? null
                  : _send,
              icon: _loading
                  ? const SizedBox(
                      width: 18,
                      height: 18,
                      child: CircularProgressIndicator(
                        strokeWidth: 2,
                        color: Colors.white,
                      ),
                    )
                  : const Icon(Icons.auto_awesome),
              label: Text(_loading ? 'Processing...' : 'Capture'),
            ),
          ],
        ),
      ),
    );
  }
}