"""独立离线核验；Python 3.12 标准库，无网络或设备访问。"""
from pathlib import Path
import json
import struct
import datetime as dt
import math
import re
import uuid

def parse(d):
    b=bytes.fromhex(d['pdu']); f=d['request_fc']
    if not b: raise ValueError('空PDU')
    if b[0]&128:
        if len(b)!=2: raise ValueError('异常PDU应为两字节')
        if (b[0]&127)!=f: raise ValueError('原始功能码不匹配')
        names={1:'Illegal Function',2:'Illegal Data Address',3:'Illegal Data Value',4:'Server Device Failure',6:'Server Device Busy'}
        return {'kind':'exception','request_fc':f,'exception_code':b[1],'name':names.get(b[1],'未知异常码')}
    if b[0]!=f: raise ValueError('原始功能码不匹配')
    if f!=3 or len(b)<2 or b[1]%2 or len(b)!=2+b[1]: raise ValueError('正常PDU结构错误')
    return {'kind':'normal','values':[int.from_bytes(b[i:i+2],'big') for i in range(2,len(b),2)]}


def main():
    root = Path(__file__).resolve().parent
    fixture = json.loads((root / "fixture.json").read_text(encoding="utf-8"))
    rows = []
    for item in fixture["cases"]:
        try:
            result = parse(item["input"])
        except ValueError as exc:
            assert "expected_error" in item, (item["case_id"], str(exc))
            assert str(exc) == item["expected_error"], (item["case_id"], str(exc))
            rows.append({"case_id": item["case_id"], "kind": item["kind"], "rejected": str(exc)})
        else:
            assert "expected_error" not in item, item["case_id"]
            assert result == item["expected"], (item["case_id"], result, item["expected"])
            rows.append({"case_id": item["case_id"], "kind": item["kind"], "result": result})
    report = {"fixture": fixture["topic"], "cases": rows, "assertions_passed": len(rows), "scope": "合成输入离线演算；未接真实设备"}
    (root / "report.json").write_text(json.dumps(report, ensure_ascii=False, indent=2) + "\n", encoding="utf-8")
    print(json.dumps({"assertions_passed": len(rows), "all_passed": True}, ensure_ascii=True))

if __name__ == "__main__":
    main()