import express from "express";
import { chromium } from "playwright";
import { execFile } from "child_process";
import { promisify } from "util";
import fs from "fs/promises";
import path from "path";
import os from "os";

const execFileAsync = promisify(execFile);
const app = express();
app.use(express.json({ limit: "50mb" }));

const PORT = process.env.PORT || 3000;

// ─── Healthcheck ───────────────────────────────────────────────────────────

app.get("/health", (_req, res) => {
  res.json({ status: "ok", timestamp: new Date().toISOString() });
});

// ─── HTML → PDF ────────────────────────────────────────────────────────────

app.post("/convert/pdf", async (req, res) => {
  const { html, options = {} } = req.body;
  if (!html) {
    return res.status(400).json({ success: false, error: "HTML обязателен" });
  }

  try {
    const pdfBuffer = await convertHtmlToPdf(html, options);
    res.json({
      success: true,
      pdf: pdfBuffer.toString("base64"),
    });
  } catch (err: any) {
    console.error("[worker] PDF conversion error:", err);
    res.status(500).json({ success: false, error: "Ошибка конвертации PDF" });
  }
});

async function convertHtmlToPdf(html: string, options: any): Promise<Buffer> {
  const launchOptions: Record<string, unknown> = {
    headless: true,
    args: ["--no-sandbox", "--disable-setuid-sandbox", "--disable-dev-shm-usage"],
  };

  if (process.env.PLAYWRIGHT_CHROMIUM_PATH) {
    launchOptions.executablePath = process.env.PLAYWRIGHT_CHROMIUM_PATH;
  }

  const browser = await chromium.launch(launchOptions);
  try {
    const page = await browser.newPage();
    await page.setContent(html, { waitUntil: "networkidle" });
    await page.waitForTimeout(300);

    const pdf = await page.pdf({
      format: options.format || "A4",
      landscape: options.landscape || false,
      printBackground: options.printBackground !== false,
      margin: options.margin
        ? {
            top: `${options.margin.top / 1440}in`,
            right: `${options.margin.right / 1440}in`,
            bottom: `${options.margin.bottom / 1440}in`,
            left: `${options.margin.left / 1440}in`,
          }
        : undefined,
      displayHeaderFooter: !!(options.headerTemplate || options.footerTemplate),
      headerTemplate: options.headerTemplate || "<div></div>",
      footerTemplate: options.footerTemplate || "<div></div>",
    });

    await page.close();
    return pdf;
  } finally {
    await browser.close();
  }
}

// ─── DOCX → PDF ────────────────────────────────────────────────────────────

app.post("/convert/docx-to-pdf", async (req, res) => {
  const { docxBase64 } = req.body;
  if (!docxBase64) {
    return res.status(400).json({ success: false, error: "DOCX base64 обязателен" });
  }

  try {
    const pdfBuffer = await convertDocxToPdf(Buffer.from(docxBase64, "base64"));
    res.json({
      success: true,
      pdf: pdfBuffer.toString("base64"),
    });
  } catch (err: any) {
    console.error("[worker] DOCX→PDF conversion error:", err);
    res.status(500).json({ success: false, error: "Ошибка конвертации DOCX→PDF" });
  }
});

async function convertDocxToPdf(docxBuffer: Buffer): Promise<Buffer> {
  const tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), "docx-pdf-"));
  const docxPath = path.join(tmpDir, "input.docx");
  const pdfPath = path.join(tmpDir, "input.pdf");

  try {
    await fs.writeFile(docxPath, docxBuffer);
    await execFileAsync("libreoffice", [
      "--headless",
      "--convert-to",
      "pdf",
      "--outdir",
      tmpDir,
      docxPath,
    ]);
    return await fs.readFile(pdfPath);
  } finally {
    await fs.rm(tmpDir, { recursive: true, force: true }).catch(() => {});
  }
}

// ─── EMF → PNG ─────────────────────────────────────────────────────────────

app.post("/convert/emf-to-png", async (req, res) => {
  const { emfBase64 } = req.body;
  if (!emfBase64) {
    return res.status(400).json({ success: false, error: "EMF base64 обязателен" });
  }

  try {
    const pngBuffer = await convertEmfToPng(Buffer.from(emfBase64, "base64"));
    res.json({
      success: true,
      png: pngBuffer.toString("base64"),
    });
  } catch (err: any) {
    console.error("[worker] EMF→PNG conversion error:", err);
    res.status(500).json({ success: false, error: "Ошибка конвертации EMF→PNG" });
  }
});

async function convertEmfToPng(emfBuffer: Buffer): Promise<Buffer> {
  const tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), "emf-png-"));
  const inputPath = path.join(tmpDir, "image.emf");
  const outputPath = path.join(tmpDir, "image.png");

  try {
    await fs.writeFile(inputPath, emfBuffer);
    await execFileAsync("libreoffice", [
      "--headless",
      "--convert-to",
      "png",
      "--outdir",
      tmpDir,
      inputPath,
    ]);
    return await fs.readFile(outputPath);
  } finally {
    await fs.rm(tmpDir, { recursive: true, force: true }).catch(() => {});
  }
}

// ─── Start ─────────────────────────────────────────────────────────────────

app.listen(PORT, () => {
  console.log(`[document-worker] Running on port ${PORT}`);
});