/* iAOP 对话助手增强版（issue #133 / PRD 5.4「④ LLM 网关 + RAG」）。
 *
 * 在 chat_widget.html（#77 雏形）之上完善：
 *   - 消息流 + 每消息元信息（路由分级 / 模型 / 耗时 / 高利害确认提示）
 *   - RAG 引用溯源：citations.json（模板知识库语料）关键词检索，回答附引用列表
 *   - 路由分级提示：镜像 core/llm-gateway/router.py 语义（local/cloud/block）
 *   - DLP 拦截反馈：镜像 core/llm-gateway/dlp.py 的 DLP_DEFAULT_RULES 内置保底规则，
 *     命中即阻止外发并给出可感知的拦截条（可转本地处理）
 *   - 三场景：NL 查询 / 报警解释（severity+点位 → 原因+处置建议，P0 提示人工确认）/
 *     交接班报告（按 handover_brief.ti.yaml 章节模板生成，计时展示 ≤2min 目标）
 *
 * 直连已部署推理服务 http://39.101.182.167:30800（OpenAI 兼容 /v1/chat/completions）。
 */
"use strict";

var INFER_BASE = "http://39.101.182.167:30800";
var state = {
  model: null,
  citations: null,   // citations.json 语料
  pending: null      // 被 DLP 拦截待处置的消息
};

/* ---------------- DLP 内置保底规则（镜像 dlp.py DLP_DEFAULT_RULES） ---------------- */
var DLP_RULES = [
  { name: "pii_id_card", category: "pii", kind: "regex",
    pattern: /\b\d{17}[\dXx]\b/, description: "身份证号（18 位）" },
  { name: "pii_mobile", category: "pii", kind: "regex",
    pattern: /\b1[3-9]\d{9}\b/, description: "中国大陆手机号" },
  { name: "pii_email", category: "pii", kind: "regex",
    pattern: /[\w.+-]+@[\w-]+\.[\w.-]+/, description: "邮箱地址" },
  { name: "pii_ipv4", category: "pii", kind: "regex",
    pattern: /\b(?:\d{1,3}\.){3}\d{1,3}\b/, description: "IPv4 地址" },
  { name: "credential_ak", category: "credential", kind: "regex",
    pattern: /\b(?:AKIA|LTAI)[0-9A-Z]{16,}\b/, description: "云访问密钥 ID" },
  { name: "credential_kv", category: "credential", kind: "regex",
    pattern: /(?:access[_-]?key|secret|password|token)\s*[:=]\s*\S+/i,
    description: "密钥/口令键值对" },
  { name: "process_formula", category: "process-keyword", kind: "keyword",
    pattern: "配方", description: "配方类敏感词" }
];

function dlpCheck(text) {
  var hits = [];
  DLP_RULES.forEach(function (r) {
    var m = text.match(r.pattern);
    if (m) hits.push({ rule: r, matched: m[0] });
  });
  return hits;
}

/* ---------------- 路由分级（镜像 router.py：block > local > cloud > 默认 local） ---------------- */
// 通用/脱敏问法（可云端）：不含点位/工艺敏感词的常识类问题
var GENERIC_RE = /^(什么是|请解释|介绍一下|怎么理解|如何理解)/;
// 本地（敏感/核心）线索：点位号、生产/工艺词
var LOCAL_HINT_RE = /([A-Z]{2,}-\d+\.|[点位炉班批纯杂温度压力流量生产工艺工况])/;

function routeDecision(text, dlpHits) {
  if (dlpHits.length) {
    return { target: "block", reason: "DLP 出站检查命中，拦截外发（fail-closed）" };
  }
  if (GENERIC_RE.test(text) && !LOCAL_HINT_RE.test(text)) {
    return { target: "cloud", reason: "通用/脱敏问题，DLP 放行，可路由云端" };
  }
  return { target: "local", reason: "敏感/核心或未知（默认保守），本地处理（数据不出厂）" };
}

/* ---------------- RAG 引用检索（citations.json 关键词重叠，Demo 级） ---------------- */
function retrieveCitations(query, topK) {
  if (!state.citations) return [];
  var terms = query.replace(/[^\w一-鿿]+/g, " ").split(" ")
    .filter(function (t) { return t.length >= 2; });
  var scored = [];
  state.citations.documents.forEach(function (doc) {
    doc.sections.forEach(function (sec) {
      var hay = doc.title + " " + sec.heading + " " + sec.snippet;
      var score = 0;
      terms.forEach(function (t) { if (hay.indexOf(t) >= 0) score += t.length; });
      if (score > 0) {
        scored.push({ title: doc.title, source: doc.source,
                      heading: sec.heading, snippet: sec.snippet, score: score });
      }
    });
  });
  scored.sort(function (a, b) { return b.score - a.score; });
  return scored.slice(0, topK || 3);
}

/* ---------------- 推理服务 ---------------- */
function checkHealth() {
  fetch(INFER_BASE + "/health").then(function (r) {
    if (!r.ok) throw new Error(r.status);
    document.getElementById("infer-dot").className = "dot ok";
    document.getElementById("infer-text").textContent = "推理服务在线";
  }).catch(function () {
    document.getElementById("infer-dot").className = "dot down";
    document.getElementById("infer-text").textContent = "推理服务不可达";
  });
}
function loadModel() {
  return fetch(INFER_BASE + "/v1/models").then(function (r) { return r.json(); })
    .then(function (d) {
      // 兼容 {"models":[...]} 与 OpenAI {"data":[{"id":...}]} 两种形态
      if (d && d.models && d.models.length) state.model = d.models[0];
      else if (d && d.data && d.data.length) state.model = d.data[0].id;
    }).catch(function () {});
}
function chatCompletions(messages) {
  return fetch(INFER_BASE + "/v1/chat/completions", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ model: state.model || "iaop-ti-cl4-v1",
                           messages: messages, max_tokens: 1024 })
  }).then(function (r) {
    if (!r.ok) throw new Error("HTTP " + r.status);
    return r.json();
  }).then(function (d) {
    var c = d && d.choices && d.choices[0];
    return (c && c.message && c.message.content) || "（空响应）";
  });
}

/* ---------------- 消息渲染 ---------------- */
function el(tag, cls, text) {
  var n = document.createElement(tag);
  if (cls) n.className = cls;
  if (text !== undefined) n.textContent = text;
  return n;
}
function addMsg(who, text, meta) {
  var box = document.getElementById("messages");
  var div = el("div", "msg " + who);
  div.appendChild(el("div", "who", who === "user" ? "我" : "iAOP"));
  var t = el("div", "text");
  t.textContent = text;
  div.appendChild(t);
  if (meta) {
    var m = el("div", "meta");
    meta.forEach(function (node) { m.appendChild(node); });
    div.appendChild(m);
  }
  box.appendChild(div);
  box.scrollTop = box.scrollHeight;
  return div;
}
function routeTag(route) {
  var map = { local: ["route-local", "路由：本地（数据不出厂）"],
              cloud: ["route-cloud", "路由：云端（脱敏放行）"],
              block: ["route-block", "路由：拦截"] };
  var v = map[route] || map.local;
  return el("span", "route-tag " + v[0], v[1]);
}
function appendCitations(msgDiv, citations) {
  if (!citations.length) {
    msgDiv.appendChild(el("div", "no-citation", "未命中知识库，以上为模型直接回答（无引用）"));
    return;
  }
  var box = el("div", "citations");
  box.appendChild(el("div", "cite-title", "引用溯源（RAG，共 " + citations.length + " 条）"));
  citations.forEach(function (c, i) {
    box.appendChild(el("div", "cite-item",
      "[" + (i + 1) + "] 《" + c.title + "》 " + c.heading + " — " + c.snippet));
  });
  msgDiv.appendChild(box);
}

/* ---------------- 场景 Prompt 构建 ---------------- */
function buildMessages(scenario, question, citations) {
  if (scenario === "alarm_explain") {
    var sev = document.getElementById("alarm-severity").value;
    var point = document.getElementById("alarm-point").value.trim() || "（未填点位）";
    return [
      { role: "system", content: "你是 iAOP 工业报警解释助手。针对告警给出结构化回答："
        + "【可能原因】分条列出；【处置建议】分条列出可执行步骤；【是否需要人工确认】。"
        + "用简体中文，简洁专业。" },
      { role: "user", content: "告警级别 " + sev + "，点位 " + point +
        "，告警描述：" + question }
    ];
  }
  if (scenario === "shift_handover") {
    var shift = document.getElementById("handover-shift").value.trim() || "本班";
    return [
      { role: "system", content: "你是 iAOP 交接班报告生成助手。按以下章节模板生成摘要"
        + "（对齐 handover_brief.ti.yaml）：一、生产概况；二、异常事项；三、安全注意事项；"
        + "四、能耗；五、待办（交下一班）。每章节 1-3 条，简体中文。" },
      { role: "user", content: "请生成 " + shift + " 的交接班报告。本班关键信息：" + question }
    ];
  }
  // nl_query：带 RAG 上下文
  var ctx = citations.map(function (c, i) {
    return "[" + (i + 1) + "] 《" + c.title + "》" + c.heading + "：" + c.snippet;
  }).join("\n");
  return [
    { role: "system", content: "你是 iAOP 工业驾驶舱 NL 查询助手，回答工艺/质量/能耗问题。"
      + (ctx ? "可参考以下知识库片段（回答中可用 [编号] 标注引用）：\n" + ctx
             : "知识库未命中，直接回答即可。")
      + "用简体中文，简洁准确。" },
    { role: "user", content: question }
  ];
}

/* ---------------- 发送主流程 ---------------- */
function doSend(question, forceLocal) {
  var scenario = document.getElementById("scenario").value;
  var citations = scenario === "nl_query" ? retrieveCitations(question, 3) : [];
  var route = forceLocal
    ? { target: "local", reason: "DLP 拦截后用户确认转本地处理" }
    : routeDecision(question + " " + (citations.map(function (c) {
        return c.snippet; }).join(" ")), dlpCheck(question));

  addMsg("user", question);
  document.getElementById("question").value = "";
  var sendBtn = document.getElementById("send");
  sendBtn.disabled = true;
  var started = Date.now();

  chatCompletions(buildMessages(scenario, question, citations))
    .then(function (answer) {
      var cost = ((Date.now() - started) / 1000).toFixed(1);
      var meta = [routeTag(route.target),
                  el("span", null, "模型: " + (state.model || "default")),
                  el("span", null, "耗时: " + cost + "s" +
                    (scenario === "shift_handover" ? "（目标 ≤ 2min）" : ""))];
      // 高利害人工确认（PRD line 333）：P0 报警解释提示值班长确认
      if (scenario === "alarm_explain" &&
          document.getElementById("alarm-severity").value === "P0") {
        meta.push(el("span", "human-tag", "⚠ P0 高利害：需值班长确认后执行"));
      }
      var div = addMsg("bot", answer, meta);
      if (scenario === "nl_query") appendCitations(div, citations);
    })
    .catch(function (e) {
      addMsg("bot", "请求失败：" + e.message + "（请确认推理服务可达）");
    })
    .finally(function () { sendBtn.disabled = false; });
}

function trySend() {
  var question = document.getElementById("question").value.trim();
  if (!question) return;
  var hits = dlpCheck(question);
  if (hits.length) {
    // DLP 拦截反馈（PRD 5.4：拦截可感知）——不发送，展示命中详情
    var banner = document.getElementById("dlp-banner");
    document.getElementById("dlp-detail").textContent =
      "命中规则 " + hits.map(function (h) {
        return h.rule.name + "（" + h.rule.description + "）";
      }).join("、") + "，已阻止外发云端（fail-closed）";
    banner.hidden = false;
    state.pending = question;
    return;
  }
  doSend(question, false);
}

/* ---------------- 启动 ---------------- */
(function init() {
  document.getElementById("send").onclick = trySend;
  document.getElementById("question").addEventListener("keydown", function (e) {
    if (e.key === "Enter") trySend();
  });
  document.getElementById("scenario").onchange = function (e) {
    var v = e.target.value;
    document.getElementById("alarm-inputs").hidden = v !== "alarm_explain";
    document.getElementById("handover-inputs").hidden = v !== "shift_handover";
    document.getElementById("question").placeholder = {
      nl_query: "请输入问题，如：氯气流量最近1小时趋势",
      alarm_explain: "描述告警现象，如：炉温骤升至 920℃ 且持续 5 分钟",
      shift_handover: "输入本班关键事件/数据，如：氯化炉运行平稳，P1 告警 2 起已确认"
    }[v];
  };
  document.getElementById("btn-local-fallback").onclick = function () {
    document.getElementById("dlp-banner").hidden = true;
    if (state.pending) { doSend(state.pending, true); state.pending = null; }
  };
  document.getElementById("btn-dlp-dismiss").onclick = function () {
    document.getElementById("dlp-banner").hidden = true;
    state.pending = null;
  };
  fetch("citations.json").then(function (r) { return r.ok ? r.json() : null; })
    .then(function (d) { state.citations = d; }).catch(function () {});
  checkHealth();
  loadModel();
})();