export type ImageStorageProvider = 'database' | 's3';

export type S3ImageStorageConfig = {
  provider: 's3';
  endpoint: string;
  region: string;
  bucket: string;
  accessKeyId: string;
  secretAccessKey: string;
  publicBaseUrl: string | null;
  keyPrefix: string;
};

const trimOptional = (value: string | undefined) => {
  const trimmed = value?.trim();
  return trimmed ? trimmed : null;
};

export const getImageStorageProvider = (): ImageStorageProvider =>
  process.env.IMAGE_STORAGE_PROVIDER === 's3' ? 's3' : 'database';

export const getS3ImageStorageConfig = (): S3ImageStorageConfig | null => {
  if (getImageStorageProvider() !== 's3') {
    return null;
  }

  const endpoint = trimOptional(process.env.S3_ENDPOINT);
  const region = trimOptional(process.env.S3_REGION);
  const bucket = trimOptional(process.env.S3_BUCKET);
  const accessKeyId = trimOptional(process.env.S3_ACCESS_KEY_ID);
  const secretAccessKey = trimOptional(process.env.S3_SECRET_ACCESS_KEY);

  if (!endpoint || !region || !bucket || !accessKeyId || !secretAccessKey) {
    return null;
  }

  return {
    provider: 's3',
    endpoint,
    region,
    bucket,
    accessKeyId,
    secretAccessKey,
    publicBaseUrl: trimOptional(process.env.S3_PUBLIC_BASE_URL),
    keyPrefix: trimOptional(process.env.S3_KEY_PREFIX) ?? 'bird-photos',
  };
};

export const isS3ImageStorageConfigured = () => getS3ImageStorageConfig() !== null;

export const buildBirdPhotoObjectKey = ({
  workspaceId,
  birdId,
  extension,
  now = new Date(),
}: {
  workspaceId: number;
  birdId: string;
  extension: string;
  now?: Date;
}) => {
  const prefix = trimOptional(process.env.S3_KEY_PREFIX) ?? 'bird-photos';
  const safeExtension = extension.replace(/^\./, '').toLowerCase() || 'bin';
  const timestamp = now.toISOString().replace(/[:.]/g, '-');

  return `${prefix}/workspace-${workspaceId}/${birdId}/${timestamp}.${safeExtension}`;
};

export const getImageExtensionFromContentType = (contentType: string) => {
  switch (contentType.toLowerCase()) {
    case 'image/jpeg':
    case 'image/jpg':
      return 'jpg';
    case 'image/png':
      return 'png';
    case 'image/webp':
      return 'webp';
    case 'image/gif':
      return 'gif';
    default:
      return 'bin';
  }
};