export interface PdfOptions {
  filename?: string;
}

const getHtml2PdfOptions = (filename?: string) => ({
  margin: 0.5,
  filename: filename ?? "document.pdf",
  image: { type: "jpeg" as const, quality: 0.98 },
  html2canvas: {
    scale: 2,
    useCORS: true,
    backgroundColor: "#ffffff",
    windowWidth: 800,
  },
  jsPDF: {
    unit: "in",
    format: "letter" as const,
    orientation: "portrait" as const,
  },
});

const createPrintWrapper = (htmlContent: string) => {
  const printWrapper = document.createElement("div");
  printWrapper.style.position = "absolute";
  printWrapper.style.left = "-9999px";
  printWrapper.style.top = "0px";
  printWrapper.className = "light"; // Prevent dark mode variables from bleeding into the physical PDF

  const element = document.createElement("div");
  element.innerHTML = htmlContent;
  // Assign standard prose layout and explicitly white/black print colors
  element.className = "prose prose-sm max-w-none p-12 bg-white text-black";
  element.style.width = "800px";
  element.style.backgroundColor = "white";
  element.style.color = "black";

  printWrapper.appendChild(element);
  document.body.appendChild(printWrapper);

  return { printWrapper, element };
};

export async function downloadPdfFromHtml(
  htmlContent: string,
  options: PdfOptions = {},
): Promise<void> {
  // @ts-ignore - Dynamic import to prevent SSR issues with window/document
  const html2pdf = (await import("html2pdf.js")).default;

  const { printWrapper, element } = createPrintWrapper(htmlContent);

  try {
    const opt = getHtml2PdfOptions(options.filename);
    await html2pdf().set(opt).from(element).save();
  } finally {
    document.body.removeChild(printWrapper);
  }
}

export async function generatePdfBlobFromHtml(
  htmlContent: string,
  options: PdfOptions = {},
): Promise<Blob> {
  // @ts-ignore - Dynamic import to prevent SSR issues with window/document
  const html2pdf = (await import("html2pdf.js")).default;

  const { printWrapper, element } = createPrintWrapper(htmlContent);

  try {
    const opt = getHtml2PdfOptions(options.filename);
    const pdfBlob = await html2pdf().set(opt).from(element).output("blob");
    return pdfBlob;
  } finally {
    document.body.removeChild(printWrapper);
  }
}