'use server';

import { auth } from "@/auth";
import { getFreshAccessToken } from "@/lib/auth-utils";
import { prisma } from "@/lib/prisma";
import { revalidatePath } from "next/cache";

export async function uploadFileAction(formData: FormData) {
  const session = await auth();
  if (!session?.user?.id) throw new Error("Unauthorized");

  const file = formData.get("file") as File;
  const folderName = "WebCalibre";
  const accessToken = await getFreshAccessToken(session.user.id);

  // 1. Create/Check WebCalibre Folder
  const folderPath = `https://graph.microsoft.com/v1.0/me/drive/root:/${folderName}`;
  const folderCheck = await fetch(folderPath, {
    headers: { Authorization: `Bearer ${accessToken}` }
  });

  if (folderCheck.status === 404) {
    await fetch(`https://graph.microsoft.com/v1.0/me/drive/root/children`, {
      method: "POST",
      headers: { Authorization: `Bearer ${accessToken}`, "Content-Type": "application/json" },
      body: JSON.stringify({ name: folderName, folder: {} })
    });
  }

  // 2. Create Upload Session (Supports files > 4MB)
  const sessionUrl = `https://graph.microsoft.com/v1.0/me/drive/root:/${folderName}/${file.name}:/createUploadSession`;
  const sessionRes = await fetch(sessionUrl, {
    method: "POST",
    headers: { Authorization: `Bearer ${accessToken}`, "Content-Type": "application/json" },
    body: JSON.stringify({ item: { "@microsoft.graph.conflictBehavior": "rename" } })
  });

  const { uploadUrl } = await sessionRes.json();

  // 3. Upload File Data
  const buffer = Buffer.from(await file.arrayBuffer());
  const uploadRes = await fetch(uploadUrl, {
    method: "PUT",
    headers: { 
      "Content-Length": `${file.size}`,
      "Content-Range": `bytes 0-${file.size - 1}/${file.size}` 
    },
    body: buffer
  });

  const driveItem = await uploadRes.json();

  // 4. Record in PostgreSQL
  await prisma.fileNode.create({
    data: {
      oneDriveId: driveItem.id,
      name: file.name,
      size: BigInt(file.size),
      isFolder: false,
      path: `/${folderName}/${file.name}`,
      ownerId: session.user.id,
      metadata: { type: file.name.split('.').pop()?.toUpperCase() }
    }
  });

  revalidatePath("/dashboard");
  return { success: true };
}