"""HTTP 中断适配：领域错误映射为状态码，执行层不依赖请求模型。"""
from fastapi import HTTPException
from runtime.events import EventBuilder
from runtime.interrupts import pack, token_for, ResumeDecision, ResumeError
from runtime.interrupts import interrupt_event, resume_value as resolve_resume, official_resume
from api.sse_events import serialize_event


def decision_from_request(request) -> ResumeDecision:
    return ResumeDecision(interrupt_token=request.interrupt_token or "", approved=request.approved,
                          status=request.status, answers=request.answers, error=request.error)


def interrupt_frame(writer, payload):
    builder = EventBuilder(writer.session_id, writer.trace_id, encode=lambda event: event)
    return serialize_event(interrupt_event(builder, payload))


def resume_value(request, state):
    try:
        return resolve_resume(decision_from_request(request), state)
    except ResumeError as exc:
        raise _http_error(exc) from exc


def to_official_resume(request, pending_count):
    try:
        return official_resume(decision_from_request(request), pending_count)
    except ResumeError as exc:
        raise _http_error(exc) from exc


def _http_error(exc: ResumeError) -> HTTPException:
    status = 400 if exc.code in {"invalid_answers", "invalid_decision"} else 409
    return HTTPException(status_code=status, detail={"code": exc.code, "message": str(exc)})