/**
 * MediaProxyAdapter
 *
 * Handles direct HTTP proxy operations for media assets.
 * This is a special case where direct fetch is needed for binary responses.
 */

import { Result } from '@/lib/contracts/Result';

export type MediaProxyError = 
  | { type: 'notFound'; message: string }
  | { type: 'serverError'; message: string }
  | { type: 'networkError'; message: string };

/**
 * Proxy media request to backend API
 * 
 * @param mediaPath - The API path to fetch media from (e.g., "/media/avatar/123")
 * @returns Result with ArrayBuffer on success, or error on failure
 */
export async function proxyMediaRequest(
  mediaPath: string
): Promise<Result<ArrayBuffer, MediaProxyError>> {
  try {
    const baseUrl = process.env.API_BASE_URL || 'http://localhost:3000';
    const response = await fetch(`${baseUrl}${mediaPath}`, {
      method: 'GET',
    });

    if (!response.ok) {
      if (response.status === 404) {
        return Result.err({ 
          type: 'notFound', 
          message: `Media not found: ${mediaPath}` 
        });
      }
      return Result.err({ 
        type: 'serverError', 
        message: `HTTP ${response.status}: ${response.statusText}` 
      });
    }

    const buffer = await response.arrayBuffer();
    return Result.ok(buffer);
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : 'Unknown error';
    return Result.err({ 
      type: 'networkError', 
      message: `Failed to fetch media: ${errorMessage}` 
    });
  }
}

/**
 * Get content type for media path
 */
// eslint-disable-next-line @typescript-eslint/no-unused-vars
export function getMediaContentType(mediaPath: string): string {
  return 'image/png';
}

/**
 * Get cache control header value
 */
export function getMediaCacheControl(): string {
  return 'public, max-age=3600';
}