# 1. 扇出声明 (Fan-out)
builder.add_edge("prepare", "eval_arch")
builder.add_edge("prepare", "eval_security")
builder.add_edge("prepare", "eval_cost")

# 2. 扇入声明 (Fan-in)
builder.add_edge("eval_arch", "aggregate")
builder.add_edge("eval_security", "aggregate")
builder.add_edge("eval_cost", "aggregate")

class UnsafeState(TypedDict):
    evaluations: list  # 未声明 Reducer 的普通列表

from typing import Annotated, List, TypedDict, Dict, Any
import operator

class SafeState(TypedDict):
    target_name: str
    # 核心：必须声明 Reducer，确保并发写入时按列表合并而不是相互覆盖
    eval_reports: Annotated[List[Dict[str, Any]], operator.add]
    final_decision: str

import operator
from typing import TypedDict, Annotated, List, Dict, Any
from langgraph.graph import StateGraph, START, END

# 1. 状态契约定义
class ProposalReviewState(TypedDict):
    proposal_title: str
    proposal_content: str
    # 并发收集的各维度评审切片
    dimension_reports: Annotated[List[Dict[str, Any]], operator.add]
    # 汇总产物
    total_score: float
    approval_status: str

# 2. 准备阶段节点
def prepare_proposal_node(state: ProposalReviewState) -> dict:
    print(f"\n[工位 1] 收到方案: 《{state['proposal_title']}》，准备派发评审任务...")
    return {}

# 3. 三个平行的评审节点 (并发执行)
def architecture_review_node(state: ProposalReviewState) -> dict:
    content = state["proposal_content"]
    print("  -> [并发审查] 架构评审节点启动...")
    # 模拟架构评分
    score = 90.0 if "高可用" in content else 70.0
    return {
        "dimension_reports": [{
            "dimension": "架构设计",
            "score": score,
            "comment": "满足分布式容灾标准" if score >= 80 else "缺少容灾备份机制"
        }]
    }

def security_review_node(state: ProposalReviewState) -> dict:
    content = state["proposal_content"]
    print("  -> [并发审查] 安全合规节点启动...")
    # 模拟安全评分
    score = 85.0 if "鉴权" in content else 60.0
    return {
        "dimension_reports": [{
            "dimension": "安全合规",
            "score": score,
            "comment": "数据敏感字段已配置加密" if score >= 80 else "未发现权限校验设计"
        }]
    }

def cost_review_node(state: ProposalReviewState) -> dict:
    content = state["proposal_content"]
    print("  -> [并发审查] 成本核算节点启动...")
    # 模拟成本评分
    score = 80.0
    return {
        "dimension_reports": [{
            "dimension": "资源成本",
            "score": score,
            "comment": "云资源预算在年度配额限制内"
        }]
    }

# 4. 汇聚节点 (Fan-in 聚合)
def aggregate_decision_node(state: ProposalReviewState) -> dict:
    reports = state["dimension_reports"]
    print(f"\n[工位 3] 收到全部 {len(reports)} 个维度的并发报告，开始裁决...")
    
    avg_score = sum(r["score"] for r in reports) / len(reports)
    status = "APPROVED" if avg_score >= 80.0 else "REJECTED"
    
    return {
        "total_score": round(avg_score, 1),
        "approval_status": status
    }

# 5. 编排图拓扑
builder = StateGraph(ProposalReviewState)

builder.add_node("prepare", prepare_proposal_node)
builder.add_node("eval_arch", architecture_review_node)
builder.add_node("eval_security", security_review_node)
builder.add_node("eval_cost", cost_review_node)
builder.add_node("aggregate", aggregate_decision_node)

builder.add_edge(START, "prepare")

# 扇出: prepare 同时触发三个节点
builder.add_edge("prepare", "eval_arch")
builder.add_edge("prepare", "eval_security")
builder.add_edge("prepare", "eval_cost")

# 扇入: 三个节点全部连接至 aggregate
builder.add_edge("eval_arch", "aggregate")
builder.add_edge("eval_security", "aggregate")
builder.add_edge("eval_cost", "aggregate")

builder.add_edge("aggregate", END)

app = builder.compile()

# 6. 执行测试
if __name__ == "__main__":
    proposal = {
        "proposal_title": "核心交易链路改造方案",
        "proposal_content": "本系统基于云原生多可用区部署，具备高可用容灾能力，并配置细粒度接口鉴权与日志审计。"
    }
    
    result = app.invoke(proposal)
    
    print("\n================ 评审交付报告 ================")
    print(f"方案: {result['proposal_title']}")
    print(f"综合评分: {result['total_score']} | 最终决策: {result['approval_status']}")
    print("各维度明细:")
    for r in result["dimension_reports"]:
        print(f"  * [{r['dimension']}] 得分: {r['score']} -> 评价: {r['comment']}")
    print("==============================================")