import express from "express";
import multer from "multer";
import {
  uploadPatchImage,
  getImageFileStream,
  isS3UploadConfigured,
} from "../services/images.js";

const upload = multer({
  storage: multer.memoryStorage(),
  limits: { fileSize: 8 * 1024 * 1024 },
  fileFilter: (_req, file, cb) => {
    const ok = /^image\/(jpeg|png|webp|gif)$/i.test(file.mimetype);
    cb(ok ? null : new Error("Invalid file type"), ok);
  },
});

function requireUser(req, res, next) {
  if (!req.session?.user?.sub) {
    res.status(401).json({ status: "error", error: "Unauthorized" });
    return;
  }
  next();
}

export function createImagesRouter() {
  const router = express.Router();

  router.post(
    "/upload",
    requireUser,
    (req, res, next) => {
      upload.single("file")(req, res, (err) => {
        if (err) {
          res
            .status(400)
            .json({ status: "error", error: err.message || "Upload error" });
          return;
        }
        next();
      });
    },
    async (req, res) => {
      try {
        if (!isS3UploadConfigured()) {
          res.status(503).json({
            status: "error",
            error: "Image upload not configured",
          });
          return;
        }
        const file = req.file;
        if (!file?.buffer) {
          res.status(400).json({ status: "error", error: "file required" });
          return;
        }
        const { id, blurHash } = await uploadPatchImage(
          file.buffer,
          file.mimetype,
        );
        res.json({ status: "ok", id, blurHash });
      } catch (e) {
        res.status(400).json({
          status: "error",
          error: e.message || "Upload failed",
        });
      }
    },
  );

  router.get("/:id", requireUser, async (req, res) => {
    const result = await getImageFileStream(req.params.id);
    if (!result) {
      res.status(404).end();
      return;
    }
    res.setHeader("Content-Type", result.contentType);
    res.setHeader("Cache-Control", "private, max-age=3600");
    result.stream.pipe(res);
  });

  return router;
}