import { NextFunction, Request, Response } from 'express';
import multer, { FileFilterCallback } from 'multer';
import { StaticRoot, sizeLimit } from '../config/Env';
import fs from 'fs/promises';
import path from 'path';

/**
 * @description  The file storage configuration
 */
export const fileStorage = multer.diskStorage({
  destination: (req, file, callback) => {
    const destination = path.join(StaticRoot, 'documents');
    // create folder if not exists
    fs.mkdir(destination, { recursive: true })
      .then(() => {
        callback(null, destination);
      })
      .catch((e) => {
        callback({ name: 'Creating Folder', message: e.message }, destination);
      });
  },
  filename: (_, file, callback) => {
    var name =
      Date.now() + '-' + file.originalname.replace(/\s/g, '-').toLowerCase();
    callback(null, name);
  },
});

/**
 * @description  The file filter configuration
 */
export const fileFilter = (
  request: Request,
  file: Express.Multer.File,
  callback: FileFilterCallback
): void => {
  // document file types
  if (
    file.mimetype === 'application/pdf' ||
    file.mimetype === 'application/msword' ||
    file.mimetype ===
      'application/vnd.openxmlformats-officedocument.wordprocessingml.document' ||
    file.mimetype === 'application/vnd.ms-excel' ||
    file.mimetype ===
      'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' ||
    file.mimetype === 'application/vnd.ms-powerpoint' ||
    file.mimetype ===
      'application/vnd.openxmlformats-officedocument.presentationml.presentation' ||
    file.mimetype === 'application/vnd.oasis.opendocument.text' ||
    file.mimetype === 'application/vnd.oasis.opendocument.presentation' ||
    file.mimetype === 'application/vnd.oasis.opendocument.spreadsheet'
  ) {
    if (file.size > sizeLimit)
      return callback(new Error('File size must be less than 5MB'));
    callback(null, true);
  } else {
    callback(new Error(`Invalid file type ${file.mimetype}`));
  }
};

/**
 * @description  Delete a file
 * @param fileName - String
 * @returns Promise<{ isDeleted: boolean }>
 */
export const deleteFile = async (
  fileName: string
): Promise<{ isDeleted: boolean }> => {
  const filePath = path.join(StaticRoot, 'documents', fileName);
  try {
    await fs.unlink(filePath);
    return { isDeleted: true };
  } catch (error) {
    return { isDeleted: false };
  }
};

export const uploadDoc = multer({
  storage: fileStorage,
  fileFilter: fileFilter,
});

/**
 * @description  The file storage configuration for thumbnails
 */
export const fileStorageThumbnails = multer.diskStorage({
  destination: (req, file, callback) => {
    const destination = path.join(StaticRoot, 'thumbnails');
    // create folder if not exists
    fs.mkdir(destination, { recursive: true })
      .then(() => {
        callback(null, destination);
      })
      .catch((e) => {
        callback({ name: 'Creating Folder', message: e.message }, destination);
      });
  },
  filename: (_, file, callback) => {
    var name =
      Date.now() + '-' + file.originalname.replace(/\s/g, '-').toLowerCase();
    callback(null, name);
  },
});

/**
 * @description  The file Thumbnail filter configuration
 */
export const fileFilterThumbnail = (
  request: Request,
  file: Express.Multer.File,
  callback: FileFilterCallback
): void => {
  // image file types
  if (
    file.mimetype === 'image/jpeg' ||
    file.mimetype === 'image/png' ||
    file.mimetype === 'image/jpg'
  ) {
    if (file.size > sizeLimit)
      return callback(new Error('File size must be less than 5MB'));
    callback(null, true);
  } else {
    callback(new Error(`Invalid file type ${file.mimetype}`));
  }
};

/**
 * @description  Delete a file thumbnail
 * @param fileName - String
 * @returns Promise<{ isDeleted: boolean }>
 */
export const deleteFileThumbnail = async (
  fileName: string
): Promise<{ isDeleted: boolean }> => {
  const filePath = path.join(StaticRoot, 'thumbnails', fileName);
  try {
    await fs.unlink(filePath);
    return { isDeleted: true };
  } catch (error) {
    return { isDeleted: false };
  }
};

export const uploadThumbnail = multer({
  storage: fileStorageThumbnails,
  fileFilter: fileFilterThumbnail,
});