// features/challenge/add/add_challenge_screen.dart
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';
import 'package:japp_flutter/core/constants/options.dart';
import 'package:japp_flutter/core/models/challenge_model.dart';
import 'package:japp_flutter/features/challenge/view_models/challenge_add_vm.dart';
import 'package:japp_flutter/features/widgets/app_dropdown.dart';
import 'package:japp_flutter/features/widgets/date_picker.dart';

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

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

    return Scaffold(
      appBar: AppBar(
        title: const Text('创建新挑战'),
        actions: [
          IconButton(
            icon: const Icon(Icons.check),
            onPressed: () async {
              await ref.read(addChallengeProvider.notifier).submitChallenge();
              if (context.mounted) Navigator.pop(context);
            },
            tooltip: '提交',
          ),
        ],
      ),
      body: challengeState.when(
        loading: () => const Center(child: CircularProgressIndicator()),
        error: (error, _) => Center(child: Text('错误: $error')),
        data: (challenge) => _BuildForm(challenge: challenge),
      ),
    );
  }
}

class _BuildForm extends ConsumerWidget {
  final ChallengeModel challenge;

  const _BuildForm({required this.challenge});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          TextFormField(
            initialValue: challenge.title,
            decoration: const InputDecoration(
              labelText: '目标',
              hintText: '请输入目标名称',
              border: OutlineInputBorder(),
            ),
            onChanged: (value) =>
                ref.read(addChallengeProvider.notifier).updateTitle(value),
          ),

          const SizedBox(height: 16),
          TextFormField(
            initialValue: challenge.description,
            decoration: const InputDecoration(
              labelText: '简介',
              hintText: '请输入目标的简介',
              border: OutlineInputBorder(),
              alignLabelWithHint: true,
            ),
            maxLines: 3,
            onChanged: (value) => ref
                .read(addChallengeProvider.notifier)
                .updateDescription(value),
          ),

          const SizedBox(height: 16),
          AppDropdown(
            label: '目标类型',
            value: challenge.actionType,
            items: challengeActionTypeOpts,
            onChanged: (value) => ref
                .read(addChallengeProvider.notifier)
                .updateActionType(value ?? 0),
          ),

          const SizedBox(height: 16),
          AppDropdown(
            label: '挑战状态',
            value: challenge.status,
            items: challengeStatusOpts,
            onChanged: (value) => ref
                .read(addChallengeProvider.notifier)
                .updateStatus(value ?? 0),
          ),

          const SizedBox(height: 16),
          AppDropdown(
            label: '挑战难度',
            value: challenge.difficulty,
            items: challengeDifficultyOpts,
            onChanged: (value) => ref
                .read(addChallengeProvider.notifier)
                .updateDifficulty(value ?? 0),
          ),

          const SizedBox(height: 16),
          _DateRangeField(
            startDate: challenge.startDate!,
            endDate: challenge.endDate!,
          ),

          const SizedBox(height: 16),
          TextFormField(
            keyboardType: TextInputType.number,
            initialValue: challenge.sort.toString(),
            decoration: const InputDecoration(
              labelText: '排序',
              border: OutlineInputBorder(),
              alignLabelWithHint: true,
            ),
            onChanged: (value) => ref
                .read(addChallengeProvider.notifier)
                .updateSort(int.parse(value)),
          ),


          const SizedBox(height: 16),
          DatePickerField(
            labelText: '计划完成日期',
            onDateSelected: (date) => ref
                .read(addChallengeProvider.notifier)
                .updatePlanFinishDate(date!),
          ),

          const SizedBox(height: 16),
          DatePickerField(
            labelText: '完成日期',
            onDateSelected: (date) => ref
                .read(addChallengeProvider.notifier)
                .updateFinishDate(date!),
          ),

          const SizedBox(height: 16),
          TextFormField(
            initialValue: challenge.remark,
            decoration: const InputDecoration(
              labelText: '备注',
              border: OutlineInputBorder(),
              alignLabelWithHint: true,
            ),
            maxLines: 3,
            onChanged: (value) =>
                ref.read(addChallengeProvider.notifier).updateRemark(value),
          ),
          const SizedBox(height: 16),


        ],
      ),
    );
  }
}

class _DateRangeField extends ConsumerWidget {
  final DateTime startDate;
  final DateTime endDate;

  const _DateRangeField({required this.startDate, required this.endDate});

  Future<void> _selectDate(
    BuildContext context,
    bool isStartDate,
    WidgetRef ref,
  ) async {
    final initialDate = isStartDate ? startDate : endDate;
    final picked = await showDatePicker(
      context: context,
      initialDate: initialDate,
      firstDate: DateTime.now(),
      lastDate: DateTime(2100),
    );

    if (picked != null) {
      final newStart = isStartDate ? picked : startDate;
      final newEnd = isStartDate ? endDate : picked;
      ref.read(addChallengeProvider.notifier).updateDateRange(newStart, newEnd);
    }
  }

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const Text('挑战周期*', style: TextStyle(fontSize: 16)),
        const SizedBox(height: 8),
        Row(
          children: [
            Expanded(
              child: OutlinedButton(
                onPressed: () => _selectDate(context, true, ref),
                child: Text(DateFormat('yyyy/MM/dd').format(startDate)),
              ),
            ),
            const Padding(
              padding: EdgeInsets.symmetric(horizontal: 8),
              child: Text('至'),
            ),
            Expanded(
              child: OutlinedButton(
                onPressed: () => _selectDate(context, false, ref),
                child: Text(DateFormat('yyyy/MM/dd').format(endDate)),
              ),
            ),
          ],
        ),
        const SizedBox(height: 4),
        Text(
          '总天数: ${endDate.difference(startDate).inDays}天',
          style: const TextStyle(color: Colors.grey),
        ),
      ],
    );
  }
}