/***********************************************************************************************************************************************************************
 * File Name: avatar.service.js
 * Type of Program: Service
 * Description: Shared avatar processing/orchestration for admin + client self-profile.
 *              Server-side authoritative resize — every avatar is normalized to a fixed
 *              200x200 JPEG regardless of what the client sends, so browser-side cropping
 *              (see AvatarUploadDialog.jsx) is a UX convenience, not the enforcement point.
 *
 * Author: Kenneth Obsequio (@lash0000)
 * Date Created: Aug. 10, 2026
 ***********************************************************************************************************************************************************************/
'use strict';

const sharp = require('sharp');
const { uploadFile, deleteFile } = require('./s3.service');

const AVATAR_SIZE   = 200;
const JPEG_QUALITY  = 90;

// ─── resizeAvatarBuffer ─────────────────────────────────────────────────────────
// Normalizes any accepted input (JPEG/PNG/WebP/GIF) into a fixed 200x200 JPEG.
// GIF animation and PNG transparency are intentionally dropped — avatars render
// in an opaque round mask, so a single static frame is all that's ever shown.

async function resizeAvatarBuffer(buffer) {
  try {
    return await sharp(buffer)
      .rotate() // respect EXIF orientation before crop
      .resize(AVATAR_SIZE, AVATAR_SIZE, { fit: 'cover', position: 'centre' })
      .jpeg({ quality: JPEG_QUALITY })
      .toBuffer();
  } catch (err) {
    throw Object.assign(new Error('Could not process the uploaded image.'), { status: 400, cause: err });
  }
}

// ─── replaceUserAvatar ──────────────────────────────────────────────────────────
// Deletes the old S3 object (if any), resizes the new upload, stores it, and
// returns the avatar metadata object. Does not persist to the user row —
// callers own that so they can merge it into personal_info their own way.

async function replaceUserAvatar(user, file) {
  const oldKey = user.personal_info?.avatar?.uuid;
  if (oldKey) await deleteFile(oldKey).catch(() => {});

  const resized = await resizeAvatarBuffer(file.buffer);

  const { url, uuid } = await uploadFile({
    buffer:       resized,
    originalname: 'avatar.jpg',
    mimetype:     'image/jpeg',
    ownerType:    'avatar',
  });

  return {
    url,
    uuid,
    name:      file.originalname,
    mime_type: 'image/jpeg',
    size:      resized.length,
  };
}

// ─── removeUserAvatar ───────────────────────────────────────────────────────────

async function removeUserAvatar(user) {
  const key = user.personal_info?.avatar?.uuid;
  if (!key) throw Object.assign(new Error('No avatar to remove.'), { status: 404 });

  await deleteFile(key).catch(() => {});
}

module.exports = { resizeAvatarBuffer, replaceUserAvatar, removeUserAvatar };