# FEndpointState

## 基本信息
- **类型**: USTRUCT(BlueprintType) with TStructOpsTypeTraits specialization
- **父类**: (none)
- **源文件**: Plugins/CharacterControl/Source/CharacterControl/Public/CommandEndpoint.h
- **模块**: CharacterControl

## 功能概述
Full state and identity of a command endpoint. Contains EndpointGuid (FGuid, unique identity), InterestedTags (FGameplayTagContainer, subscription list), bIsActive, bIsContinuousFriendly, bIsAsynchronous flags. Custom operator= preserves GUID on copy while updating config fields. TStructOpsTypeTraits with WithCopy=true forces UE to use C++ copy path instead of memcpy.

## 设计用意
Solves endpoint identity problem in dynamic routing graph. Custom copy operator prevents CDO/Blueprint default overwriting of runtime-assigned GUID. Tag subscription model enables declarative routing (no hard references between producers/consumers).

## 职责范围
Identity and configuration for one endpoint in the routing graph. GUID serves as registry key in UCommandRouter. Tags determine which commands the endpoint receives.

## 项目内依赖
| 依赖项 | 关系 | 源文件 |
|--------|------|--------|
| (none) | | |

## 对外接口
FEndpointState 定义命令端点的完整身份和配置。在 UCommandRouter::EndpointState、UEndpointComponent::EndpointState、UEndpointDispatcher::CurrentState 中作为成员使用。

- **EndpointGuid** (FGuid, VisibleAnywhere, BlueprintReadOnly): 端点的唯一标识符，自动初始化为 NewGuid()，路由注册表以此为 Key。自定义 operator= 在目标已有身份时保留 GUID，防止 CDO/蓝图赋值覆盖运行时身份
- **InterestedTags** (FGameplayTagContainer, EditDefaultsOnly, BlueprintReadOnly): 端点订阅的命令标签集合，决定端点接收哪些命令
- **bIsActive** (bool, EditDefaultsOnly, BlueprintReadOnly): 端点活跃开关，false 时 IsEndpointMatched 直接返回 false，端点不接收任何命令
- **bIsContinuousFriendly** (bool, EditDefaultsOnly, BlueprintReadOnly): 是否接收连续命令，false 的端点不会被投递连续命令
- **bIsAsynchronous** (bool, EditDefaultsOnly, BlueprintReadOnly): 异步端点标志，端点应在自身 ReceiveCommand 中自行调度异步执行以保证线程安全

FEndpointState 有 TStructOpsTypeTraits<WithCopy=true> 特化，强制 UE 使用 C++ 拷贝路径（而非 memcpy），确保自定义 operator= 被正确调用。

## 使用方法
FEndpointState 在不同位置设定和使用：

- **端点配置**: `Plugins/CharacterControl/Source/CharacterControl/Private/EndpointComponent.cpp:13` -- UEndpointComponent 构造函数中设置 `EndpointState.bIsActive = true`
- **路由器配置**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:8-11` -- UCommandRouter 构造函数中设置 `bIsActive=true, bIsContinuousFriendly=true, bIsAsynchronous=false`
- **注册时读取**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:52-53` -- RegisterEndpoint 读取 EndpointGuid 验证有效性和唯一性
- **匹配时读取**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:266-298` -- IsEndpointMatched 读取 bIsActive 和 bIsContinuousFriendly 决定匹配结果
- **状态变更**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:33-42` -- SetRouterState 只更新配置字段，保留 Guid 并广播 StateChangedDelegate

## 用例
- **GUID 保护机制**: `Plugins/CharacterControl/Source/CharacterControl/Public/CommandEndpoint.h:88-105` -- 自定义 operator= 通过 bGuidAssigned 标志判断：未分配时拷贝 GUID，已分配时保留现有 GUID。防止蓝图 CDO 属性灌装覆盖运行时赋予的唯一 ID
- **端点注册验证**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:53-58` -- RegisterEndpoint 检查 EndpointGuid 有效性，无效时拒绝注册并输出警告
- **自注册防护**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:65-69` -- 检查端点 GUID 是否等于路由器自身 GUID，防止拓扑环路
- **匹配判断入口**: `Plugins/CharacterControl/Source/CharacterControl/Private/CommandRouter.cpp:268-271` -- bIsActive 为 false 时直接返回 false，快速短路所有匹配逻辑