import ft from "file-type";
import core 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";
import { AssetPaths, FolderPaths } from "./serverInit";
const simpleThumb = require("simple-thumbnail");
//const ffmpeg = require("ffmpeg-static");

var Bluebird = require("bluebird");

Bluebird.promisifyAll(gm.prototype);

/** @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.fromFile(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);
      const thumbnail = await imageThumbnail(file, {
        responseType: "buffer",
        height: 250,
        width: 250,
      });
      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);
  }
}

/** @returns {string} Returns the relative path from the file to the thumbnail on the server. This must be converted to a URL. */
export async function GenerateOptimized(
  file: string
  //thumbPath: string
) {
  const type: core.FileTypeResult | undefined = await ft.fromFile(file);
  let thumbnailExtension: string = GetThumbnailExtension(type, true);
  let thumbPath: string = path.join(
    path.dirname(file),
    FolderPaths.OptimizedSubDir,
    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("Optimized image 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("Optimized image being created for : " + thumbPath);
      await OptimizeImage(file, thumbPath);
    }
    return path.relative(path.dirname(file), thumbPath);
  } catch (err) {
    logger.error("Error when genenerating optimized image:", {
      thumbPath,
      err,
      message: (err as Error).message,
    });
    return path.relative(path.dirname(file), AssetPaths.File);
  }
}

async function OptimizeImage(file: string, optimizedPath: string) {
  const fileOnDisk: Buffer = await fs.readFile(file);
  return new Promise<string>((resolve, reject) => {
    const result = gm(fileOnDisk)
      .resize(1500)
      .quality(75)
      .write(optimizedPath, (error) => {
        if (error) reject(error.message);
        resolve(optimizedPath);
      });
  });
}

async function GeneratePdfThumbnail(file: string, thumbPath: string) {
  const fileOnDisk: Buffer = await fs.readFile(file);
  return new Promise<string>((resolve, reject) => {
    const result = gm(fileOnDisk)
      .selectFrame(0)
      .setFormat("png")
      .resize(200, 200, "!") // Resize to fixed 200px width, maintaining aspect ratio
      .quality(75)
      .write(thumbPath, (error) => {
        if (error) reject(error.message);
        resolve(thumbPath);
      });
  });
}

function GetThumbnailExtension(
  file: core.FileTypeResult | undefined,
  useJpeg?: boolean
) {
  if (useJpeg) return ".jpg";
  if (file === undefined) return ".png";
  return ".png";
}