feat: add smart extraction trigger mvp

tests/smart-trigger.mjs

@@ -0,0 +1,132 @@
+import assert from "node:assert/strict";
+
+function getSmartTriggerDecision(chat, lastProcessed, settings) {
+  const DEFAULT_TRIGGER_KEYWORDS = [
+    "突然",
+    "没想到",
+    "原来",
+    "其实",
+    "发现",
+    "背叛",
+    "死亡",
+    "复活",
+    "恢复记忆",
+    "失忆",
+    "告白",
+    "暴露",
+    "秘密",
+    "计划",
+    "规则",
+    "契约",
+    "位置",
+    "地点",
+    "离开",
+    "来到",
+  ];
+
+  const pendingMessages = chat
+    .slice(lastProcessed + 1)
+    .filter((msg) => !msg.is_system)
+    .map((msg) => ({
+      role: msg.is_user ? "user" : "assistant",
+      content: msg.mes || "",
+    }));
+
+  if (pendingMessages.length === 0) {
+    return { triggered: false, score: 0, reasons: [] };
+  }
+
+  const reasons = [];
+  let score = 0;
+  const combinedText = pendingMessages.map((m) => m.content).join("\n");
+
+  const keywordHits = DEFAULT_TRIGGER_KEYWORDS.filter((keyword) =>
+    combinedText.includes(keyword),
+  );
+  if (keywordHits.length > 0) {
+    score += Math.min(2, keywordHits.length);
+    reasons.push(`关键词: ${keywordHits.slice(0, 3).join(", ")}`);
+  }
+
+  const customPatterns = String(settings.triggerPatterns || "")
+    .split(/\r?\n|,/)
+    .map((s) => s.trim())
+    .filter(Boolean);
+  for (const pattern of customPatterns) {
+    try {
+      const regex = new RegExp(pattern, "i");
+      if (regex.test(combinedText)) {
+        score += 2;
+        reasons.push(`自定义触发: ${pattern}`);
+        break;
+      }
+    } catch {
+      // ignore invalid regex
+    }
+  }
+
+  const roleSwitchCount = pendingMessages.reduce((count, message, index) => {
+    if (index === 0) return count;
+    return count + (message.role !== pendingMessages[index - 1].role ? 1 : 0);
+  }, 0);
+  if (roleSwitchCount >= 2) {
+    score += 1;
+    reasons.push("多轮往返互动");
+  }
+
+  const punctuationHits = (combinedText.match(/[!?！？]/g) || []).length;
+  if (punctuationHits >= 2) {
+    score += 1;
+    reasons.push("情绪/冲突波动");
+  }
+
+  const entityLikeHits =
+    combinedText.match(
+      /[A-Z][a-z]{2,}|[\u4e00-\u9fff]{2,6}(先生|小姐|王国|城|镇|村|学院|组织|公司|小队|军团)/g,
+    ) || [];
+  if (entityLikeHits.length > 0) {
+    score += 1;
+    reasons.push("疑似新实体/新地点");
+  }
+
+  const threshold = Math.max(1, settings.smartTriggerThreshold || 2);
+  return {
+    triggered: score >= threshold,
+    score,
+    reasons,
+  };
+}
+
+const noTrigger = getSmartTriggerDecision(
+  [
+    { is_user: true, mes: "今天天气不错。" },
+    { is_user: false, mes: "是的，我们继续赶路。" },
+  ],
+  -1,
+  { triggerPatterns: "", smartTriggerThreshold: 3 },
+);
+assert.equal(noTrigger.triggered, false);
+
+const keywordTrigger = getSmartTriggerDecision(
+  [
+    { is_user: true, mes: "我们突然发现城堡地下有秘密。" },
+    { is_user: false, mes: "原来失踪的人都被关在这里！" },
+  ],
+  -1,
+  { triggerPatterns: "", smartTriggerThreshold: 2 },
+);
+assert.equal(keywordTrigger.triggered, true);
+assert.ok(keywordTrigger.score >= 2);
+
+const customTrigger = getSmartTriggerDecision(
+  [
+    { is_user: true, mes: "她轻声说出真相。" },
+    { is_user: false, mes: "所有人都沉默了。" },
+  ],
+  -1,
+  { triggerPatterns: "真相|背叛", smartTriggerThreshold: 2 },
+);
+assert.equal(customTrigger.triggered, true);
+assert.ok(customTrigger.reasons.some((r) => r.includes("自定义触发")));
+
+console.log("smart-trigger tests passed");