/**
 * NAC知识引擎 — PDF合规报告生成模块 (v16)
 *
 * 功能：
 * 1. 按辖区/资产类型/语言筛选规则
 * 2. 生成专业PDF报告（NAC品牌头部、规则表格、多语言内容）
 * 3. 上传到S3并返回下载URL
 *
 * 技术：pdfkit + S3存储
 */

import PDFDocument from "pdfkit";
import { getMongoDb, COLLECTIONS } from "./mongodb";
import { storagePut } from "./storage";
import path from "path";
import fs from "fs";

// ─── 类型定义 ──────────────────────────────────────────────────────
export interface ReportConfig {
  jurisdiction?: string;
  assetType?: string;
  lang: string;
  title: string;
  includeDisabled?: boolean;
  excludeJurisdictions?: string[];
}

// ─── 辖区全称映射 ─────────────────────────────────────────────────
const JURISDICTION_NAMES: Record<string, Record<string, string>> = {
  CN: { zh: "中国大陆", en: "Mainland China", ar: "الصين", ja: "中国本土", ko: "중국 본토", fr: "Chine continentale", ru: "Материковый Китай" },
  HK: { zh: "中国香港", en: "Hong Kong SAR", ar: "هونغ كونغ", ja: "香港", ko: "홍콩", fr: "Hong Kong", ru: "Гонконг" },
  SG: { zh: "新加坡", en: "Singapore", ar: "سنغافورة", ja: "シンガポール", ko: "싱가포르", fr: "Singapour", ru: "Сингапур" },
  US: { zh: "美国", en: "United States", ar: "الولايات المتحدة", ja: "アメリカ", ko: "미국", fr: "États-Unis", ru: "США" },
  EU: { zh: "欧盟", en: "European Union", ar: "الاتحاد الأوروبي", ja: "欧州連合", ko: "유럽연합", fr: "Union européenne", ru: "Европейский союз" },
  AE: { zh: "阿联酋", en: "United Arab Emirates", ar: "الإمارات العربية المتحدة", ja: "アラブ首長国連邦", ko: "아랍에미리트", fr: "Émirats arabes unis", ru: "ОАЭ" },
};

// ─── 语言标签映射 ─────────────────────────────────────────────────
const LANG_LABELS: Record<string, string> = {
  zh: "中文（简体）", en: "English", ar: "العربية", ja: "日本語", ko: "한국어", fr: "Français", ru: "Русский",
};

// ─── 查找可用字体（支持中文） ──────────────────────────────────────
function findCJKFont(): string | null {
  const candidates = [
    "/usr/share/fonts/truetype/noto/NotoSansCJK-Regular.ttc",
    "/usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc",
    "/usr/share/fonts/truetype/wqy/wqy-microhei.ttc",
    "/usr/share/fonts/truetype/arphic/uming.ttc",
    "/usr/share/fonts/truetype/droid/DroidSansFallbackFull.ttf",
  ];
  for (const p of candidates) {
    if (fs.existsSync(p)) return p;
  }
  return null;
}

// ─── 主PDF生成函数 ────────────────────────────────────────────────
export async function generateComplianceReport(config: ReportConfig): Promise<{
  url: string;
  filename: string;
  ruleCount: number;
  fileSize: number;
}> {
  const db = await getMongoDb();
  if (!db) throw new Error("数据库连接失败");

  const lang = config.lang || "zh";

  // ── 查询规则数据 ──────────────────────────────────────────────
  const filter: Record<string, unknown> = {};
  if (config.jurisdiction && config.jurisdiction !== "ALL") filter.jurisdiction = config.jurisdiction;
  if (config.assetType && config.assetType !== "ALL") filter.assetType = config.assetType;
  if (!config.includeDisabled) filter.status = "active";

  const rules = await db.collection(COLLECTIONS.COMPLIANCE_RULES)
    .find(filter)
    .sort({ jurisdiction: 1, assetType: 1, createdAt: 1 })
    .toArray() as any[];

  if (rules.length === 0) throw new Error("没有找到符合条件的规则，请调整筛选条件");

  // ── 生成PDF ──────────────────────────────────────────────────
  const cjkFont = findCJKFont();

  const doc = new PDFDocument({
    size: "A4",
    margins: { top: 60, bottom: 60, left: 60, right: 60 },
    info: {
      Title: config.title,
      Author: "NAC NewAssetChain",
      Subject: "Compliance Rules Report",
      Creator: "NAC Knowledge Engine v16",
    },
  });

  const chunks: Buffer[] = [];
  doc.on("data", (chunk: Buffer) => chunks.push(chunk));

  // 注册CJK字体（如果可用）
  if (cjkFont) {
    try {
      doc.registerFont("CJK", cjkFont);
    } catch {
      // 字体注册失败，使用默认字体
    }
  }

  const useCJK = !!cjkFont;
  const fontName = useCJK ? "CJK" : "Helvetica";
  const fontBold = useCJK ? "CJK" : "Helvetica-Bold";

  // ── 封面页 ────────────────────────────────────────────────────
  // 顶部品牌色条
  doc.rect(0, 0, doc.page.width, 8).fill("#1a56db");

  // NAC Logo区域
  doc.rect(60, 40, 480, 80).fill("#0f172a");
  doc.font(fontBold).fontSize(22).fillColor("#60a5fa")
    .text("NAC", 80, 58);
  doc.font(fontName).fontSize(10).fillColor("#94a3b8")
    .text("NewAssetChain — RWA Native Blockchain", 80, 85);
  doc.font(fontBold).fontSize(14).fillColor("#ffffff")
    .text("Knowledge Engine", 300, 65, { align: "right", width: 220 });

  // 报告标题
  doc.moveDown(3);
  doc.font(fontBold).fontSize(20).fillColor("#1e293b")
    .text(config.title, 60, 160, { align: "center", width: 480 });

  // 报告元信息
  const metaY = 210;
  doc.font(fontName).fontSize(10).fillColor("#64748b");

  const jurisdictionLabel = config.jurisdiction && config.jurisdiction !== "ALL"
    ? (JURISDICTION_NAMES[config.jurisdiction]?.[lang] || config.jurisdiction)
    : (lang === "zh" ? "全部辖区" : "All Jurisdictions");

  const assetTypeLabel = config.assetType && config.assetType !== "ALL"
    ? config.assetType
    : (lang === "zh" ? "全部资产类型" : "All Asset Types");

  const metaItems = [
    { label: lang === "zh" ? "辖区" : "Jurisdiction", value: jurisdictionLabel },
    { label: lang === "zh" ? "资产类型" : "Asset Type", value: assetTypeLabel },
    { label: lang === "zh" ? "显示语言" : "Language", value: LANG_LABELS[lang] || lang },
    { label: lang === "zh" ? "规则总数" : "Total Rules", value: `${rules.length}` },
    { label: lang === "zh" ? "生成时间" : "Generated", value: new Date().toLocaleString("zh-CN", { timeZone: "Asia/Shanghai" }) },
  ];

  metaItems.forEach((item, i) => {
    const x = i % 2 === 0 ? 80 : 320;
    const y = metaY + Math.floor(i / 2) * 22;
    doc.font(fontBold).fontSize(9).fillColor("#475569").text(item.label + "：", x, y);
    doc.font(fontName).fontSize(9).fillColor("#1e293b").text(item.value, x + 60, y);
  });

  // 分隔线
  doc.moveTo(60, metaY + 80).lineTo(540, metaY + 80).strokeColor("#e2e8f0").lineWidth(1).stroke();

  // ── 目录（按辖区分组） ────────────────────────────────────────
  const jurisdictions = Array.from(new Set(rules.map((r: any) => r.jurisdiction as string))).sort();

  doc.addPage();
  doc.rect(0, 0, doc.page.width, 8).fill("#1a56db");

  doc.font(fontBold).fontSize(14).fillColor("#1e293b")
    .text(lang === "zh" ? "目录" : "Table of Contents", 60, 40);
  doc.moveTo(60, 60).lineTo(540, 60).strokeColor("#e2e8f0").lineWidth(0.5).stroke();

  let tocY = 75;
  jurisdictions.forEach((j, idx) => {
    const jRules = rules.filter((r: any) => r.jurisdiction === j);
    const jName = JURISDICTION_NAMES[j]?.[lang] || j;
    doc.font(fontBold).fontSize(10).fillColor("#1a56db")
      .text(`${idx + 1}. ${j} — ${jName}`, 60, tocY);
    doc.font(fontName).fontSize(9).fillColor("#64748b")
      .text(`${jRules.length} ${lang === "zh" ? "条规则" : "rules"}`, 480, tocY, { align: "right", width: 60 });
    tocY += 20;
  });

  // ── 规则内容页（按辖区分组） ──────────────────────────────────
  jurisdictions.forEach((jurisdiction) => {
    const jRules = rules.filter((r: any) => r.jurisdiction === jurisdiction);
    const jName = JURISDICTION_NAMES[jurisdiction]?.[lang] || jurisdiction;

    doc.addPage();
    doc.rect(0, 0, doc.page.width, 8).fill("#1a56db");

    // 辖区标题
    doc.rect(60, 30, 480, 36).fill("#0f172a");
    doc.font(fontBold).fontSize(14).fillColor("#60a5fa")
      .text(jurisdiction, 75, 40);
    doc.font(fontName).fontSize(11).fillColor("#94a3b8")
      .text(jName, 130, 43);
    doc.font(fontName).fontSize(9).fillColor("#64748b")
      .text(`${jRules.length} ${lang === "zh" ? "条规则" : "rules"}`, 480, 43, { align: "right", width: 60 });

    let ruleY = 85;

    jRules.forEach((rule: any, idx: number) => {
      // 检查是否需要新页
      if (ruleY > doc.page.height - 120) {
        doc.addPage();
        doc.rect(0, 0, doc.page.width, 8).fill("#1a56db");
        ruleY = 30;
      }

      const ruleName = rule.ruleNameI18n?.[lang] || rule.ruleName;
      const ruleDesc = rule.descriptionI18n?.[lang] || rule.description;

      // 规则序号背景
      doc.rect(60, ruleY, 480, 1).fill("#e2e8f0");
      ruleY += 8;

      // 规则编号 + 名称
      doc.font(fontBold).fontSize(10).fillColor("#1a56db")
        .text(`${idx + 1}.`, 60, ruleY, { width: 20 });
      doc.font(fontBold).fontSize(10).fillColor("#1e293b")
        .text(ruleName, 82, ruleY, { width: 400 });

      // 资产类型 + 状态徽章
      const badgeText = `${rule.assetType}${rule.required ? (lang === "zh" ? " · 强制" : " · Required") : ""}`;
      doc.font(fontName).fontSize(8).fillColor("#64748b")
        .text(badgeText, 82, ruleY + 14, { width: 200 });

      ruleY += 28;

      // 规则描述
      const descHeight = Math.ceil(ruleDesc.length / 80) * 12 + 8;
      if (ruleY + descHeight > doc.page.height - 80) {
        doc.addPage();
        doc.rect(0, 0, doc.page.width, 8).fill("#1a56db");
        ruleY = 30;
      }

      doc.font(fontName).fontSize(9).fillColor("#374151")
        .text(ruleDesc, 82, ruleY, { width: 440, lineGap: 2 });

      ruleY = (doc as any).y + 12;

      // 标签
      if (rule.tags && rule.tags.length > 0) {
        doc.font(fontName).fontSize(7.5).fillColor("#94a3b8")
          .text(`${lang === "zh" ? "标签" : "Tags"}: ${rule.tags.join(", ")}`, 82, ruleY);
        ruleY = (doc as any).y + 8;
      }
    });
  });

  // ── 页脚（每页） ─────────────────────────────────────────────
  const pageCount = (doc as any).bufferedPageRange?.()?.count || 1;
  for (let i = 0; i < pageCount; i++) {
    doc.switchToPage(i);
    doc.rect(0, doc.page.height - 30, doc.page.width, 30).fill("#f8fafc");
    doc.font(fontName).fontSize(7.5).fillColor("#94a3b8")
      .text(
        `NAC NewAssetChain Knowledge Engine · ${config.title} · ${new Date().toLocaleDateString("zh-CN")} · Page ${i + 1}`,
        60, doc.page.height - 18,
        { align: "center", width: 480 }
      );
  }

  doc.end();

  // 等待PDF生成完成
  const pdfBuffer = await new Promise<Buffer>((resolve, reject) => {
    doc.on("end", () => resolve(Buffer.concat(chunks)));
    doc.on("error", reject);
  });

  // ── 上传到S3 ──────────────────────────────────────────────────
  const timestamp = Date.now();
  const safeTitle = config.title.replace(/[^a-zA-Z0-9\u4e00-\u9fa5]/g, "-").slice(0, 30);
  const filename = `nac-compliance-report-${safeTitle}-${timestamp}.pdf`;
  const fileKey = `reports/${filename}`;

  const { url } = await storagePut(fileKey, pdfBuffer, "application/pdf");

  return {
    url,
    filename,
    ruleCount: rules.length,
    fileSize: pdfBuffer.length,
  };
}