import { fileTypeFromFile } from "file-type";
import { FileTypeResult } from "file-type/core";
import fs from "fs-extra";
import { access } from "fs/promises";
import gm from "gm";
import imageThumbnail from "image-thumbnail";
import path from "path";
import { logger } from "../server.js";
import { AssetPaths, FolderPaths } from "./serverInit.js";
//@ts-ignore
import simpleThumb from "simple-thumbnail";
//const ffmpeg = require("ffmpeg-static");

/** @returns {string} Returns the relative path from the file to the thumbnail on the server. This must be converted to a URL. */
export default async function GenerateThumbnail(
  file: string
  //thumbPath: string
) {
  // const type: core.FileTypeResult | undefined = await ft.fileTypeFromFile(file);
  const type: FileTypeResult | undefined = await fileTypeFromFile(file);
  let thumbnailExtension: string = GetThumbnailExtension(type);
  let thumbPath: string = path.join(
    path.dirname(file),
    FolderPaths.ThumbsSubDir,
    path.parse(path.basename(file)).name + thumbnailExtension
  );
  try {
    //Ensure the thumbs directory exists.
    await fs.ensureDir(path.dirname(thumbPath));

    try {
      await access(thumbPath);
      logger.debug("Thumbnail already exists for : " + thumbPath);
      return path.relative(path.dirname(file), thumbPath);
    } catch {}

    //Check to see if the file is an image, PDF, or video.

    if (type?.mime === "application/pdf") {
      const fileOnDisk: Buffer = await fs.readFile(file);
      await GeneratePdfThumbnail(file, thumbPath);
    } else if (type?.mime.startsWith("video")) {
      await simpleThumb(file, thumbPath, "250x?", {
        // path: ffmpeg,
      });
    } else {
      logger.debug("Thumbnail being created for : " + thumbPath);
      //Ignoring typescript as the interface is lacking a parameter.
      // @ts-ignore
      const thumbnail = await imageThumbnail(file, {
        responseType: "buffer",
        height: 250,
        width: 250,
        failOnError: false
      });
      console.log("Image success.");
      await fs.writeFile(thumbPath, thumbnail);
    }
    return path.relative(path.dirname(file), thumbPath);
  } catch (err) {
    logger.error("Error when genenerating thumbnail:", {
      thumbPath,
      err,
      message: (err as Error).message
    });
    return path.relative(path.dirname(file), AssetPaths.File);
  }
}

async function GeneratePdfThumbnail(file: string, thumbPath: string) {
  const fileOnDisk: Buffer = await fs.readFile(file);
  return new Promise<string>((resolve, reject) => {
    gm(fileOnDisk)
      .selectFrame(0)
      .setFormat("png")
      .resize(200, 200, "!")
      .quality(75)
      .write(thumbPath, (error) => {
        if (error) {
          reject(error);
        } else {
          resolve(thumbPath);
        }
      });
  });
}

function GetThumbnailExtension(file: FileTypeResult | undefined) {
  if (file === undefined) return ".png";
  return ".png";
}