"use client";

import { useCallback, useState } from "react";

import { api } from "@/lib/api/client";
import { PROCEED, toVM, type ClarifyDecisionVM } from "./clarify";

export type ClarifyStatus = "idle" | "checking" | "asking" | "proceed" | "error";

export interface UseRewriteClarify {
  status: ClarifyStatus;
  // status=asking 时的待答问题（含选项）；其它时为 null。
  decision: ClarifyDecisionVM | null;
  // 预检：调 rewrite/clarify 端点，返回 VM 供调用方同步分支。失败=放行（needClarification=false），不阻塞整章重写。
  check: (
    projectId: string,
    chapterNo: number,
    feedback: string,
    priorDraft: string,
  ) => Promise<ClarifyDecisionVM>;
  reset: () => void;
}

// 整章重写侧 AI 反问澄清预检（WFW-9 M2，路线A 两阶段之「问题」阶段——refine/clarify 的章级孪生）。
// 「再沟通/重写」意见含糊/极短时先调独立非流式端点让 AI 反问；needClarification=false 或失败=放行去既有 rewrite SSE。
export function useRewriteClarify(): UseRewriteClarify {
  const [status, setStatus] = useState<ClarifyStatus>("idle");
  const [decision, setDecision] = useState<ClarifyDecisionVM | null>(null);

  const check = useCallback<UseRewriteClarify["check"]>(
    async (projectId, chapterNo, feedback, priorDraft) => {
      setStatus("checking");
      try {
        const { data, error } = await api.POST(
          "/projects/{project_id}/chapters/{chapter_no}/rewrite/clarify",
          {
            params: { path: { project_id: projectId, chapter_no: chapterNo } },
            body: { feedback, prior_draft: priorDraft },
          },
        );
        if (error || !data) {
          setStatus("proceed");
          setDecision(null);
          return PROCEED;
        }
        const vm = toVM(data);
        if (vm.needClarification && vm.questions.length > 0) {
          setStatus("asking");
          setDecision(vm);
        } else {
          setStatus("proceed");
          setDecision(null);
        }
        return vm;
      } catch {
        setStatus("proceed");
        setDecision(null);
        return PROCEED;
      }
    },
    [],
  );

  const reset = useCallback((): void => {
    setStatus("idle");
    setDecision(null);
  }, []);

  return { status, decision, check, reset };
}