water-management-system/mobile/lib/services/revenue_service.dart

/// 营收管理相关 API 调用服务
/// 当前使用 mock 数据，后端 API 就绪后替换为真实请求
class RevenueService {
  RevenueService._internal();
  static final RevenueService instance = RevenueService._internal();
  factory RevenueService() => instance;

  // ==================== Mock 数据 ====================

  /// 获取月度账单列表
  Future<List<BillItem>> getBillList({String? period, BillStatus? status}) async {
    await Future.delayed(const Duration(milliseconds: 800));
    final bills = [
      BillItem(
        id: 'B202405-001',
        customerName: '张三',
        customerAddress: '阳光小区3-501',
        meterId: 'S001-501',
        period: '2024-05',
        previousReading: 1250.0,
        currentReading: 1285.5,
        usage: 35.5,
        unitPrice: 2.41,
        amount: 85.50,
        status: BillStatus.paid,
        dueDate: DateTime(2024, 6, 15),
        payTime: DateTime(2024, 6, 10, 14, 30),
        payMethod: PayMethod.wechat,
      ),
      BillItem(
        id: 'B202405-002',
        customerName: '李四',
        customerAddress: '翠湖花园2-302',
        meterId: 'S002-302',
        period: '2024-05',
        previousReading: 890.0,
        currentReading: 940.0,
        usage: 50.0,
        unitPrice: 2.41,
        amount: 120.00,
        status: BillStatus.unpaid,
        dueDate: DateTime(2024, 6, 15),
      ),
      BillItem(
        id: 'B202405-003',
        customerName: '王五',
        customerAddress: '东方名城8-101',
        meterId: 'S003-101',
        period: '2024-05',
        previousReading: 2100.0,
        currentReading: 2127.0,
        usage: 27.0,
        unitPrice: 2.41,
        amount: 65.20,
        status: BillStatus.paid,
        dueDate: DateTime(2024, 6, 15),
        payTime: DateTime(2024, 6, 8, 9, 15),
        payMethod: PayMethod.alipay,
      ),
      BillItem(
        id: 'B202405-004',
        customerName: '赵六',
        customerAddress: '锦绣家园5-601',
        meterId: 'S004-601',
        period: '2024-05',
        previousReading: 1560.0,
        currentReading: 1601.0,
        usage: 41.0,
        unitPrice: 2.41,
        amount: 98.80,
        status: BillStatus.overdue,
        dueDate: DateTime(2024, 6, 15),
      ),
      BillItem(
        id: 'B202405-005',
        customerName: '孙七',
        customerAddress: '阳光小区1-203',
        meterId: 'S001-203',
        period: '2024-05',
        previousReading: 780.0,
        currentReading: 810.0,
        usage: 30.0,
        unitPrice: 2.41,
        amount: 72.30,
        status: BillStatus.unpaid,
        dueDate: DateTime(2024, 6, 15),
      ),
      BillItem(
        id: 'B202405-006',
        customerName: '周八',
        customerAddress: '城东商铺A-12',
        meterId: 'S005-A12',
        period: '2024-05',
        previousReading: 3200.0,
        currentReading: 3450.0,
        usage: 250.0,
        unitPrice: 3.85,
        amount: 962.50,
        status: BillStatus.paid,
        dueDate: DateTime(2024, 6, 15),
        payTime: DateTime(2024, 6, 5, 10, 0),
        payMethod: PayMethod.bankTransfer,
      ),
      BillItem(
        id: 'B202405-007',
        customerName: '吴九',
        customerAddress: '翠湖花园5-102',
        meterId: 'S002-102',
        period: '2024-05',
        previousReading: 450.0,
        currentReading: 478.0,
        usage: 28.0,
        unitPrice: 2.41,
        amount: 67.48,
        status: BillStatus.paid,
        dueDate: DateTime(2024, 6, 15),
        payTime: DateTime(2024, 6, 12, 16, 45),
        payMethod: PayMethod.cash,
      ),
      BillItem(
        id: 'B202405-008',
        customerName: '郑十',
        customerAddress: '东方名城3-802',
        meterId: 'S003-802',
        period: '2024-05',
        previousReading: 1100.0,
        currentReading: 1155.0,
        usage: 55.0,
        unitPrice: 2.41,
        amount: 132.55,
        status: BillStatus.overdue,
        dueDate: DateTime(2024, 6, 15),
      ),
    ];

    var result = bills;
    if (status != null) {
      result = result.where((b) => b.status == status).toList();
    }
    if (period != null) {
      result = result.where((b) => b.period == period).toList();
    }
    return result;
  }

  /// 搜索用户（抄表录入用）
  Future<List<CustomerInfo>> searchCustomers(String keyword) async {
    await Future.delayed(const Duration(milliseconds: 500));
    final customers = [
      CustomerInfo(id: 'C001', name: '张三', address: '阳光小区3-501', meterId: 'S001-501', meterModel: 'LXS-20E', phone: '13800138001'),
      CustomerInfo(id: 'C002', name: '李四', address: '翠湖花园2-302', meterId: 'S002-302', meterModel: 'LXS-25E', phone: '13800138002'),
      CustomerInfo(id: 'C003', name: '王五', address: '东方名城8-101', meterId: 'S003-101', meterModel: 'LXS-20E', phone: '13800138003'),
      CustomerInfo(id: 'C004', name: '赵六', address: '锦绣家园5-601', meterId: 'S004-601', meterModel: 'LXS-32E', phone: '13800138004'),
      CustomerInfo(id: 'C005', name: '孙七', address: '阳光小区1-203', meterId: 'S001-203', meterModel: 'LXS-20E', phone: '13800138005'),
      CustomerInfo(id: 'C006', name: '周八', address: '城东商铺A-12', meterId: 'S005-A12', meterModel: 'LXS-50E', phone: '13800138006'),
      CustomerInfo(id: 'C007', name: '吴九', address: '翠湖花园5-102', meterId: 'S002-102', meterModel: 'LXS-20E', phone: '13800138007'),
      CustomerInfo(id: 'C008', name: '郑十', address: '东方名城3-802', meterId: 'S003-802', meterModel: 'LXS-25E', phone: '13800138008'),
    ];
    if (keyword.isEmpty) return customers;
    return customers
        .where((c) =>
            c.name.contains(keyword) ||
            c.meterId.contains(keyword) ||
            c.address.contains(keyword))
        .toList();
  }

  /// 提交抄表读数
  Future<bool> submitMeterReading({
    required String meterId,
    required double reading,
    String? photoPath,
    String? remark,
  }) async {
    await Future.delayed(const Duration(milliseconds: 700));
    return true;
  }

  /// 获取缴费记录
  Future<List<PaymentRecord>> getPaymentRecords({PaymentStatus? status}) async {
    await Future.delayed(const Duration(milliseconds: 700));
    final records = [
      PaymentRecord(
        id: 'P2024-001',
        customerName: '张三',
        customerAddress: '阳光小区3-501',
        meterId: 'S001-501',
        amount: 85.50,
        period: '2024-05',
        payTime: DateTime(2024, 6, 10, 14, 30),
        method: PayMethod.wechat,
        status: PaymentStatus.success,
        operator: '系统',
      ),
      PaymentRecord(
        id: 'P2024-002',
        customerName: '王五',
        customerAddress: '东方名城8-101',
        meterId: 'S003-101',
        amount: 65.20,
        period: '2024-05',
        payTime: DateTime(2024, 6, 8, 9, 15),
        method: PayMethod.alipay,
        status: PaymentStatus.success,
        operator: '系统',
      ),
      PaymentRecord(
        id: 'P2024-003',
        customerName: '周八',
        customerAddress: '城东商铺A-12',
        meterId: 'S005-A12',
        amount: 962.50,
        period: '2024-05',
        payTime: DateTime(2024, 6, 5, 10, 0),
        method: PayMethod.bankTransfer,
        status: PaymentStatus.success,
        operator: '柜台-李芳',
      ),
      PaymentRecord(
        id: 'P2024-004',
        customerName: '吴九',
        customerAddress: '翠湖花园5-102',
        meterId: 'S002-102',
        amount: 67.48,
        period: '2024-05',
        payTime: DateTime(2024, 6, 12, 16, 45),
        method: PayMethod.cash,
        status: PaymentStatus.success,
        operator: '柜台-李芳',
      ),
      PaymentRecord(
        id: 'P2024-005',
        customerName: '赵六',
        customerAddress: '锦绣家园5-601',
        meterId: 'S004-601',
        amount: 98.80,
        period: '2024-05',
        payTime: null,
        method: null,
        status: PaymentStatus.pending,
        operator: null,
      ),
      PaymentRecord(
        id: 'P2024-006',
        customerName: '郑十',
        customerAddress: '东方名城3-802',
        meterId: 'S003-802',
        amount: 132.55,
        period: '2024-05',
        payTime: null,
        method: null,
        status: PaymentStatus.overdue,
        operator: null,
      ),
    ];
    if (status != null) {
      return records.where((r) => r.status == status).toList();
    }
    return records;
  }

  /// 执行缴费操作
  Future<PaymentResult> payBill({
    required String billId,
    required PayMethod method,
  }) async {
    await Future.delayed(const Duration(milliseconds: 1000));
    return PaymentResult(
      success: true,
      transactionId: 'TXN${DateTime.now().millisecondsSinceEpoch}',
      message: '缴费成功',
    );
  }

  /// 获取营收概览
  Future<RevenueSummary> getRevenueSummary() async {
    await Future.delayed(const Duration(milliseconds: 600));
    return const RevenueSummary(
      totalAmount: 358620,
      paidAmount: 312450,
      unpaidAmount: 46170,
      overdueAmount: 12800,
      totalCustomers: 1280,
      paidCustomers: 1050,
      unpaidCustomers: 180,
      overdueCustomers: 50,
      collectionRate: 87.1,
      monthOverMonth: 5.8,
    );
  }
}

// ==================== 数据模型 ====================

/// 账单状态
enum BillStatus {
  paid('已缴费'),
  unpaid('待缴费'),
  overdue('欠费');

  final String label;
  const BillStatus(this.label);
}

/// 支付方式
enum PayMethod {
  wechat('微信支付'),
  alipay('支付宝'),
  bankTransfer('银行转账'),
  cash('现金'),
  other('其他');

  final String label;
  const PayMethod(this.label);
}

/// 缴费状态
enum PaymentStatus {
  success('已缴'),
  pending('待缴'),
  overdue('欠费');

  final String label;
  const PaymentStatus(this.label);
}

/// 账单
class BillItem {
  final String id;
  final String customerName;
  final String customerAddress;
  final String meterId;
  final String period;
  final double previousReading;
  final double currentReading;
  final double usage;
  final double unitPrice;
  final double amount;
  final BillStatus status;
  final DateTime dueDate;
  final DateTime? payTime;
  final PayMethod? payMethod;

  const BillItem({
    required this.id,
    required this.customerName,
    required this.customerAddress,
    required this.meterId,
    required this.period,
    required this.previousReading,
    required this.currentReading,
    required this.usage,
    required this.unitPrice,
    required this.amount,
    required this.status,
    required this.dueDate,
    this.payTime,
    this.payMethod,
  });
}

/// 客户信息
class CustomerInfo {
  final String id;
  final String name;
  final String address;
  final String meterId;
  final String meterModel;
  final String phone;

  const CustomerInfo({
    required this.id,
    required this.name,
    required this.address,
    required this.meterId,
    required this.meterModel,
    required this.phone,
  });
}

/// 缴费记录
class PaymentRecord {
  final String id;
  final String customerName;
  final String customerAddress;
  final String meterId;
  final double amount;
  final String period;
  final DateTime? payTime;
  final PayMethod? method;
  final PaymentStatus status;
  final String? operator;

  const PaymentRecord({
    required this.id,
    required this.customerName,
    required this.customerAddress,
    required this.meterId,
    required this.amount,
    required this.period,
    this.payTime,
    this.method,
    required this.status,
    this.operator,
  });

  String get payTimeStr {
    if (payTime == null) return '-';
    return '${payTime!.year}-${payTime!.month.toString().padLeft(2, '0')}-${payTime!.day.toString().padLeft(2, '0')} '
        '${payTime!.hour.toString().padLeft(2, '0')}:${payTime!.minute.toString().padLeft(2, '0')}';
  }
}

/// 缴费结果
class PaymentResult {
  final bool success;
  final String transactionId;
  final String message;

  const PaymentResult({
    required this.success,
    required this.transactionId,
    required this.message,
  });
}

/// 营收概览
class RevenueSummary {
  final double totalAmount;
  final double paidAmount;
  final double unpaidAmount;
  final double overdueAmount;
  final int totalCustomers;
  final int paidCustomers;
  final int unpaidCustomers;
  final int overdueCustomers;
  final double collectionRate;
  final double monthOverMonth;

  const RevenueSummary({
    required this.totalAmount,
    required this.paidAmount,
    required this.unpaidAmount,
    required this.overdueAmount,
    required this.totalCustomers,
    required this.paidCustomers,
    required this.unpaidCustomers,
    required this.overdueCustomers,
    required this.collectionRate,
    required this.monthOverMonth,
  });
}