graph TD
    subgraph "用户管理模块"
        User((User))
        Doctor((Doctor))
    end
    
    subgraph "宠物管理模块"
        Pet((Pet))
    end
    
    subgraph "预约管理模块"
        Appointment((Appointment))
    end
    
    subgraph "就诊管理模块"
        Visit((Visit))
    end
    
    subgraph "处方管理模块"
        Prescription((Prescription))
        PrescriptionItem((PrescriptionItem))
    end
    
    subgraph "药品管理模块"
        Drug((Drug))
    end
    
    subgraph "订单管理模块"
        Order((Order))
    end
    
    subgraph "库存管理模块"
        StockIn((StockIn))
        StockOut((StockOut))
    end
    
    subgraph "病历管理模块"
        MedicalRecord((MedicalRecord))
    end
    
    subgraph "消息通知模块"
        Message((Message))
        Notice((Notice))
    end
    
    subgraph "报表管理模块"
        Report((Report))
    end
    
    subgraph "疫苗管理模块"
        VaccineRecord((VaccineRecord))
    end

    %% 用户关系
    User --> Pet : 拥有(ownerId)
    User --> Appointment : 创建(customerId)
    User --> Visit : 就诊(customerId)
    User --> Prescription : 处方(customerId)
    User --> Order : 订单(customerId)
    User --> Message : 发送/接收(senderId/receiverId)
    User --> Notice : 发布(publisherId)
    User --> Report : 生成(generatedBy)
    User --> StockIn : 入库(operatorId)
    User --> StockOut : 出库(operatorId)
    
    %% 医生关系
    Doctor --> Appointment : 接诊(doctorId)
    Doctor --> Visit : 诊治(doctorId)
    Doctor --> Prescription : 开具(doctorId)
    Doctor --> MedicalRecord : 记录(doctorId)
    Doctor --> VaccineRecord : 注射(doctorId)
    
    %% 宠物关系
    Pet --> Appointment : 预约(petId)
    Pet --> Visit : 就诊(petId)
    Pet --> VaccineRecord : 接种(petId)
    
    %% 预约关系
    Appointment --> Visit : 关联(appointmentId)
    
    %% 就诊关系
    Visit --> Prescription : 对应(visitId)
    Visit --> Order : 产生(visitId)
    Visit --> MedicalRecord : 记录(visitId)
    
    %% 处方关系
    Prescription --> PrescriptionItem : 包含(prescriptionId)
    
    %% 药品关系
    Drug --> PrescriptionItem : 包含(drugId)
    Drug --> StockIn : 入库(drugId)
    Drug --> StockOut : 出库(drugId)
    
    %% 报表关系
    Report --> Appointment : 统计
    Report --> Visit : 统计
    Report --> Order : 统计
    Report --> Prescription : 统计

    style User fill:#e1f5fe
    style Doctor fill:#e8f5e8
    style Pet fill:#fff3e0
    style Appointment fill:#f3e5f5
    style Visit fill:#e0f2f1
    style Prescription fill:#ede7f6
    style Drug fill:#e0f7fa
    style Order fill:#fff8e1