import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import '../../services/water_service.dart';

/// 今日值班页面
class DispatchPage extends StatefulWidget {
  const DispatchPage({super.key});
  @override
  State<DispatchPage> createState() => _DispatchPageState();
}

class _DispatchPageState extends State<DispatchPage> {
  final WaterService _service = WaterService.instance;
  DutyInfo? _dutyInfo;
  bool _isLoading = true;
  String? _error;

  @override
  void initState() {
    super.initState();
    _loadData();
  }

  Future<void> _loadData() async {
    setState(() {
      _isLoading = true;
      _error = null;
    });
    try {
      final data = await _service.getTodayDuty();
      if (mounted) {
        setState(() {
          _dutyInfo = data;
          _isLoading = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _error = e.toString();
          _isLoading = false;
        });
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Scaffold(
      appBar: AppBar(
        title: const Text('今日值班'),
        centerTitle: true,
        actions: [
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: _isLoading ? null : _loadData,
          ),
        ],
      ),
      body: _buildBody(theme),
    );
  }

  Widget _buildBody(ThemeData theme) {
    if (_isLoading) {
      return const Center(child: CircularProgressIndicator());
    }
    if (_error != null) {
      return Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Icon(Icons.error_outline, size: 48, color: theme.colorScheme.error),
            const SizedBox(height: 16),
            Text('加载失败', style: theme.textTheme.titleMedium),
            const SizedBox(height: 16),
            FilledButton.icon(
              onPressed: _loadData,
              icon: const Icon(Icons.refresh),
              label: const Text('重试'),
            ),
          ],
        ),
      );
    }

    final info = _dutyInfo!;
    final dateFormat = DateFormat('yyyy年MM月dd日');

    return RefreshIndicator(
      onRefresh: _loadData,
      child: ListView(
        padding: const EdgeInsets.all(16),
        children: [
          // 班次概览卡片
          _ShiftOverviewCard(
            date: dateFormat.format(info.date),
            shiftName: info.shiftName,
            shiftTime: info.shiftTime,
            memberCount: info.members.length + 1,
            instructionCount: info.instructions.length,
          ),
          const SizedBox(height: 20),

          // 值班长
          _SectionHeader(title: '值班长', icon: Icons.star),
          const SizedBox(height: 8),
          _PersonCard(
            person: info.leader,
            isLeader: true,
          ),
          const SizedBox(height: 20),

          // 值班人员
          _SectionHeader(title: '值班人员', icon: Icons.people),
          const SizedBox(height: 8),
          ...info.members.map((member) => Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: _PersonCard(person: member),
              )),
          const SizedBox(height: 20),

          // 调度指令台账
          _SectionHeader(
            title: '调度指令台账',
            icon: Icons.assignment,
            trailing: Text(
              '${info.instructions.length} 条',
              style: TextStyle(fontSize: 13, color: Colors.grey.shade600),
            ),
          ),
          const SizedBox(height: 8),
          ...info.instructions.map((instruction) => Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: _InstructionCard(instruction: instruction),
              )),
          const SizedBox(height: 16),
        ],
      ),
    );
  }
}

/// 班次概览卡片
class _ShiftOverviewCard extends StatelessWidget {
  final String date;
  final String shiftName;
  final String shiftTime;
  final int memberCount;
  final int instructionCount;

  const _ShiftOverviewCard({
    required this.date,
    required this.shiftName,
    required this.shiftTime,
    required this.memberCount,
    required this.instructionCount,
  });

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

    return Card(
      elevation: 0,
      color: theme.colorScheme.primaryContainer.withAlpha(80),
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
      child: Padding(
        padding: const EdgeInsets.all(20),
        child: Column(
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(Icons.calendar_today, size: 18, color: primary),
                const SizedBox(width: 8),
                Text(
                  date,
                  style: TextStyle(
                    fontSize: 16,
                    fontWeight: FontWeight.w600,
                    color: primary,
                  ),
                ),
                const SizedBox(width: 12),
                Container(
                  padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 3),
                  decoration: BoxDecoration(
                    color: primary.withAlpha(30),
                    borderRadius: BorderRadius.circular(12),
                  ),
                  child: Text(
                    shiftName,
                    style: TextStyle(fontSize: 12, color: primary, fontWeight: FontWeight.w600),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 12),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                _InfoColumn(icon: Icons.schedule, label: '值班时间', value: shiftTime),
                Container(width: 1, height: 40, color: Colors.grey.shade300),
                _InfoColumn(icon: Icons.people, label: '值班人数', value: '$memberCount 人'),
                Container(width: 1, height: 40, color: Colors.grey.shade300),
                _InfoColumn(icon: Icons.assignment, label: '调度指令', value: '$instructionCount 条'),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

class _InfoColumn extends StatelessWidget {
  final IconData icon;
  final String label;
  final String value;

  const _InfoColumn({required this.icon, required this.label, required this.value});

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Icon(icon, size: 20, color: Colors.grey.shade600),
        const SizedBox(height: 4),
        Text(label, style: TextStyle(fontSize: 11, color: Colors.grey.shade600)),
        const SizedBox(height: 2),
        Text(value, style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600)),
      ],
    );
  }
}

/// 段落标题
class _SectionHeader extends StatelessWidget {
  final String title;
  final IconData icon;
  final Widget? trailing;

  const _SectionHeader({required this.title, required this.icon, this.trailing});

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Row(
      children: [
        Icon(icon, size: 20, color: theme.colorScheme.primary),
        const SizedBox(width: 8),
        Text(title, style: theme.textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600)),
        const Spacer(),
        if (trailing != null) trailing!,
      ],
    );
  }
}

/// 值班人员卡片
class _PersonCard extends StatelessWidget {
  final DutyPerson person;
  final bool isLeader;

  const _PersonCard({required this.person, this.isLeader = false});

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

    return Card(
      elevation: 0,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(12),
        side: BorderSide(
          color: isLeader ? theme.colorScheme.primary.withAlpha(80) : Colors.grey.shade200,
        ),
      ),
      child: Padding(
        padding: const EdgeInsets.all(14),
        child: Row(
          children: [
            CircleAvatar(
              radius: 22,
              backgroundColor: isLeader
                  ? theme.colorScheme.primary.withAlpha(30)
                  : Colors.grey.shade100,
              child: Text(
                person.name.substring(0, 1),
                style: TextStyle(
                  fontSize: 16,
                  fontWeight: FontWeight.w600,
                  color: isLeader ? theme.colorScheme.primary : Colors.grey.shade700,
                ),
              ),
            ),
            const SizedBox(width: 12),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Row(
                    children: [
                      Text(
                        person.name,
                        style: theme.textTheme.titleSmall?.copyWith(fontWeight: FontWeight.w600),
                      ),
                      if (isLeader) ...[
                        const SizedBox(width: 6),
                        Container(
                          padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 1),
                          decoration: BoxDecoration(
                            color: Colors.amber.shade100,
                            borderRadius: BorderRadius.circular(4),
                          ),
                          child: Text(
                            '值班长',
                            style: TextStyle(fontSize: 10, color: Colors.amber.shade800),
                          ),
                        ),
                      ],
                    ],
                  ),
                  const SizedBox(height: 4),
                  Text(
                    person.role,
                    style: TextStyle(fontSize: 12, color: Colors.grey.shade600),
                  ),
                ],
              ),
            ),
            // 拨打电话按钮
            Container(
              decoration: BoxDecoration(
                color: Colors.green.shade50,
                borderRadius: BorderRadius.circular(8),
              ),
              child: IconButton(
                icon: Icon(Icons.phone, size: 20, color: Colors.green.shade700),
                onPressed: () {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('拨打电话: ${person.phone}'),
                      duration: const Duration(seconds: 2),
                    ),
                  );
                },
              ),
            ),
          ],
        ),
      ),
    );
  }
}

/// 调度指令卡片
class _InstructionCard extends StatelessWidget {
  final DutyInstruction instruction;

  const _InstructionCard({required this.instruction});

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final statusColor = Color(instruction.status.color);

    return Card(
      elevation: 0,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(12),
        side: BorderSide(color: Colors.grey.shade200),
      ),
      child: Padding(
        padding: const EdgeInsets.all(14),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Expanded(
                  child: Text(
                    instruction.title,
                    style: theme.textTheme.titleSmall?.copyWith(fontWeight: FontWeight.w600),
                  ),
                ),
                Container(
                  padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 2),
                  decoration: BoxDecoration(
                    color: statusColor.withAlpha(30),
                    borderRadius: BorderRadius.circular(6),
                  ),
                  child: Text(
                    instruction.status.label,
                    style: TextStyle(fontSize: 11, color: statusColor, fontWeight: FontWeight.w500),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 8),
            Text(
              instruction.content,
              style: TextStyle(fontSize: 13, color: Colors.grey.shade700, height: 1.5),
            ),
            const SizedBox(height: 10),
            Row(
              children: [
                Icon(Icons.access_time, size: 12, color: Colors.grey.shade500),
                const SizedBox(width: 4),
                Text(
                  instruction.time,
                  style: TextStyle(fontSize: 11, color: Colors.grey.shade500),
                ),
                const SizedBox(width: 16),
                Icon(Icons.person_outline, size: 12, color: Colors.grey.shade500),
                const SizedBox(width: 4),
                Text(
                  instruction.issuer,
                  style: TextStyle(fontSize: 11, color: Colors.grey.shade500),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}