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

import 'package:timetrack/features/entries/domain/entries_provider.dart';
import 'package:timetrack/features/entries/domain/time_entry.dart';
import 'package:timetrack/features/projects/domain/project.dart';
import 'package:timetrack/features/projects/domain/projects_provider.dart';

class EntryFormSheet extends ConsumerStatefulWidget {
  const EntryFormSheet({super.key, this.existing});

  final TimeEntry? existing;

  static Future<void> show(BuildContext context, {TimeEntry? existing}) {
    return showModalBottomSheet<void>(
      context: context,
      isScrollControlled: true,
      shape: const RoundedRectangleBorder(
        borderRadius: BorderRadius.vertical(top: Radius.circular(20)),
      ),
      builder: (_) => EntryFormSheet(existing: existing),
    );
  }

  @override
  ConsumerState<EntryFormSheet> createState() => _EntryFormSheetState();
}

class _EntryFormSheetState extends ConsumerState<EntryFormSheet> {
  Project? _project;
  late DateTime _startTime;
  late DateTime _endTime;
  final _noteController = TextEditingController();
  String? _error;

  @override
  void initState() {
    super.initState();
    final now = DateTime.now();
    _startTime = widget.existing?.startTime ?? now;
    _endTime = widget.existing?.endTime ?? now;
    _noteController.text = widget.existing?.note ?? '';
  }

  @override
  void dispose() {
    _noteController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final projectsAsync = ref.watch(activeProjectsProvider);

    return Padding(
      padding: EdgeInsets.only(
        bottom: MediaQuery.of(context).viewInsets.bottom + 16,
        top: 16,
        left: 16,
        right: 16,
      ),
      child: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            widget.existing == null ? 'Add Entry' : 'Edit Entry',
            style: Theme.of(context).textTheme.titleLarge,
          ),
          const SizedBox(height: 16),

          // Project picker
          projectsAsync.when(
            data: (projects) => DropdownButtonFormField<Project>(
              initialValue: _project ??
                  (widget.existing != null
                      ? projects
                          .where((p) => p.id == widget.existing!.projectId)
                          .firstOrNull
                      : null),
              items: projects
                  .map((p) => DropdownMenuItem(
                        value: p,
                        child: Row(
                          children: [
                            CircleAvatar(
                              backgroundColor: Color(p.colorValue),
                              radius: 8,
                            ),
                            const SizedBox(width: 8),
                            Text(p.name),
                          ],
                        ),
                      ))
                  .toList(),
              onChanged: (p) => setState(() => _project = p),
              decoration: const InputDecoration(
                border: OutlineInputBorder(),
                labelText: 'Project',
              ),
            ),
            loading: () => const LinearProgressIndicator(),
            error: (e, _) => Text('Error: $e'),
          ),
          const SizedBox(height: 12),

          // Start / End time
          Row(
            children: [
              Expanded(
                child: _TimeField(
                  label: 'Start',
                  value: _startTime,
                  onChanged: (dt) => setState(() => _startTime = dt),
                ),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: _TimeField(
                  label: 'End',
                  value: _endTime,
                  onChanged: (dt) => setState(() => _endTime = dt),
                ),
              ),
            ],
          ),
          const SizedBox(height: 12),

          // Note
          TextField(
            controller: _noteController,
            decoration: const InputDecoration(
              border: OutlineInputBorder(),
              labelText: 'Note (optional)',
            ),
          ),

          if (_error != null) ...[
            const SizedBox(height: 8),
            Text(_error!, style: TextStyle(color: Theme.of(context).colorScheme.error)),
          ],

          const SizedBox(height: 16),
          Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: [
              TextButton(
                onPressed: () => Navigator.pop(context),
                child: const Text('Cancel'),
              ),
              const SizedBox(width: 8),
              FilledButton(
                onPressed: _save,
                child: const Text('Save'),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Future<void> _save() async {
    if (_project == null) {
      setState(() => _error = 'Please select a project.');
      return;
    }
    if (!_endTime.isAfter(_startTime)) {
      setState(() => _error = 'End time must be after start time.');
      return;
    }

    final duration = _endTime.difference(_startTime);
    final notifier = ref.read(entriesNotifierProvider.notifier);
    final now = DateTime.now();

    if (widget.existing == null) {
      await notifier.create(TimeEntry(
        id: 0,
        projectId: _project!.id,
        startTime: _startTime,
        endTime: _endTime,
        durationSeconds: duration.inSeconds,
        note: _noteController.text.trim().isEmpty
            ? null
            : _noteController.text.trim(),
        createdAt: now,
      ));
    } else {
      await notifier.updateEntry(widget.existing!.copyWith(
        projectId: _project!.id,
        startTime: _startTime,
        endTime: _endTime,
        durationSeconds: duration.inSeconds,
        note: _noteController.text.trim().isEmpty
            ? null
            : _noteController.text.trim(),
      ));
    }

    if (mounted) Navigator.pop(context);
  }
}

class _TimeField extends StatelessWidget {
  const _TimeField({
    required this.label,
    required this.value,
    required this.onChanged,
  });

  final String label;
  final DateTime value;
  final ValueChanged<DateTime> onChanged;

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: () async {
        final date = await showDatePicker(
          context: context,
          initialDate: value,
          firstDate: DateTime(2020),
          lastDate: DateTime.now().add(const Duration(days: 1)),
        );
        if (date == null || !context.mounted) return;
        final time = await showTimePicker(
          context: context,
          initialTime: TimeOfDay.fromDateTime(value),
        );
        if (time == null) return;
        onChanged(DateTime(date.year, date.month, date.day, time.hour, time.minute));
      },
      child: InputDecorator(
        decoration: InputDecoration(
          border: const OutlineInputBorder(),
          labelText: label,
        ),
        child: Text(
          '${value.day.toString().padLeft(2, '0')}.${value.month.toString().padLeft(2, '0')} '
          '${value.hour.toString().padLeft(2, '0')}:${value.minute.toString().padLeft(2, '0')}',
        ),
      ),
    );
  }
}