import { Router, type IRouter, type Request, type Response, type NextFunction } from "express";
import { getUpload, getFileInput } from "../upload.js";
import { getImageInfo, generateThumbnail } from "../services/image.js";
import { throwValidation } from "../services/errors.js";
import { cleanupMiddleware } from "../middleware/cleanup.js";
import type { ThumbnailParams } from "../types.js";

export function parseQuality(value: string | undefined, defaultValue = 85): number {
  if (value === undefined) return defaultValue;
  const parsed = parseInt(value, 10);
  if (isNaN(parsed)) return defaultValue;
  return Math.min(100, Math.max(1, parsed));
}

export function createImageRoutes(): IRouter {
  const router: IRouter = Router();
  const upload = getUpload();

  router.post(
    "/info",
    upload.single("file"),
    cleanupMiddleware,
    async (req: Request, res: Response, next: NextFunction) => {
      const releaseQueue = (res as any).locals?.releaseQueue;
      const signal = (req as any).abortController?.signal;
      try {
        if (!req.file) {
          throwValidation("invalid-image", "No file uploaded");
        }

        const input = getFileInput(req.file!);
        const info = await getImageInfo(input, req.file!.size, signal);
        res.locals.opMeta = `mtype=${info.mtype}, size=${info.width}x${info.height}`;
        res.json(info);
      } catch (err) {
        next(err);
      } finally {
        if (releaseQueue) releaseQueue();
      }
    }
  );

  router.post(
    "/thumbnail",
    upload.single("file"),
    cleanupMiddleware,
    async (req: Request, res: Response, next: NextFunction) => {
      const releaseQueue = (res as any).locals?.releaseQueue;
      const signal = (req as any).abortController?.signal;
      try {
        if (!req.file) {
          throwValidation("invalid-image", "No file uploaded");
        }

        const input = getFileInput(req.file!);
        const width = parseInt(req.query.width as string, 10);
        const height = parseInt(req.query.height as string, 10);
        const quality = parseQuality(req.query.quality as string);
        const format = (req.query.format as string) || "jpeg";
        const mode = (req.query.mode as string) || "fit";

        if (isNaN(width) || isNaN(height) || width <= 0 || height <= 0) {
          throwValidation("invalid-image", "width and height must be positive integers");
        }

        if (!["jpeg", "webp", "png"].includes(format)) {
          throwValidation("invalid-image", `Unsupported format: ${format}`);
        }

        if (!["fit", "crop"].includes(mode)) {
          throwValidation("invalid-image", `Unsupported mode: ${mode}`);
        }

        const params: ThumbnailParams = {
          width,
          height,
          quality,
          format: format as "jpeg" | "webp" | "png",
          mode: mode as "fit" | "crop",
        };

        res.locals.opMeta = `size=${width}x${height}, fmt=${format}, mode=${mode}, q=${params.quality}`;
        const { data, mtype } = await generateThumbnail(input, params, signal);
        res.setHeader("Content-Type", mtype);
        res.send(data);
      } catch (err) {
        next(err);
      } finally {
        if (releaseQueue) releaseQueue();
      }
    }
  );

  return router;
}