// BehavioralSignatureDetector（veridrop detectors/behavioral_signature.py）：几道短题看 Claude 的典型行为
// （markdown 加粗、列表、婉拒时给替代方案）。expected 命中且 unexpected 不命中算一条命中；分 = 命中权重 / 总权重 × 100。

import { BEHAVIORAL_SIGNATURES } from "../data/behavioral_signatures.js";
import type { DetectorResult } from "../models.js";
import { cpSlice, joinText, pySearch } from "../py.js";
import { ActiveDetector, errText, type DetectClient } from "./base.js";

const MAX_TOKENS = 350;

interface Signature {
  id: string;
  prompt: string;
  system?: string;
  expected_patterns?: readonly string[];
  unexpected_patterns?: readonly string[];
  expected_match?: string;
  weight?: number;
}

export function evaluateSignature(text: string, sig: Signature): boolean {
  const expected = sig.expected_patterns ?? [];
  const unexpected = sig.unexpected_patterns ?? [];
  const mode = sig.expected_match ?? "all";
  const rx = (p: string) => pySearch(p, text, "im"); // re.IGNORECASE | re.MULTILINE
  if (unexpected.some(rx)) return false;
  if (expected.length === 0) return true;
  if (mode === "any") return expected.some(rx);
  return expected.every(rx);
}

export class BehavioralSignatureDetector extends ActiveDetector {
  readonly name = "behavioral_signature";
  readonly displayName = "行为签名验证";
  readonly weight = 15;

  async run(client: DetectClient, model: string): Promise<DetectorResult> {
    const signatures = BEHAVIORAL_SIGNATURES.signatures as readonly Signature[];
    if (signatures.length === 0) return this.result("skip", 0, { reason: "no signatures loaded" });

    const results: Record<string, unknown>[] = [];
    let weightedHits = 0;
    let maxWeight = 0;
    for (const sig of signatures) {
      const w = Number(sig.weight ?? 1);
      maxWeight += w;
      const body: Record<string, unknown> = {
        model,
        max_tokens: MAX_TOKENS,
        temperature: 0,
        messages: [{ role: "user", content: sig.prompt }],
      };
      if (sig.system) body["system"] = sig.system;
      let resp: Record<string, unknown>;
      try {
        ({ resp } = await client.messagesCreate(body));
      } catch (e) {
        results.push({ id: sig.id, hit: false, error: errText(e), weight: w });
        continue;
      }
      const text = joinText(resp["content"]);
      const hit = evaluateSignature(text, sig);
      results.push({ id: sig.id, hit, weight: w, response_excerpt: cpSlice(text, 200) });
      if (hit) weightedHits += w;
    }

    const score = maxWeight ? (weightedHits / maxWeight) * 100 : 0;
    return this.result(score >= 70 ? "pass" : "fail", score, {
      signatures: results,
      hits: results.filter((r) => r["hit"]).length,
      total: results.length,
    });
  }
}