import { IRequest } from 'itty-router';

/**
 * CORS headers to allow any domain to call our service
 */
const CORS_HEADERS = {
	'Access-Control-Allow-Origin': '*',
	'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE, OPTIONS',
	'Access-Control-Allow-Headers': 'Content-Type, Authorization, x-openai-api-key, x-claude-api-key, x-anthropic-api-key, x-google-api-key, x-google-ai-api-key, x-groq-api-key, x-mistral-api-key, x-openrouter-api-key, x-cohere-api-key, x-ai21-api-key, x-xai-api-key, x-deepseek-api-key, x-cloudflare-api-key, x-cloudflare-account-id, x-stability-api-key, x-falai-api-key',
	'Access-Control-Max-Age': '86400', // 24 hours
};

/**
 * CORS middleware that adds CORS headers to all responses
 */
export function corsMiddleware(req: IRequest) {
	// Handle OPTIONS preflight request
	if (req.method === 'OPTIONS') {
		return new Response(null, {
			status: 204,
			headers: CORS_HEADERS
		});
	}

	// Continue to next handler
	return undefined;
}

/**
 * Wrap a response with CORS headers
 */
export function withCors(response: Response): Response {
	const newHeaders = new Headers(response.headers);

	// Add CORS headers
	for (const [key, value] of Object.entries(CORS_HEADERS)) {
		newHeaders.set(key, value);
	}

	return new Response(response.body, {
		status: response.status,
		statusText: response.statusText,
		headers: newHeaders
	});
}

/**
 * Create a JSON response with CORS headers
 */
export function jsonWithCors(data: any, init?: ResponseInit): Response {
	const headers = new Headers(init?.headers || {});
	headers.set('Content-Type', 'application/json');

	// Add CORS headers
	for (const [key, value] of Object.entries(CORS_HEADERS)) {
		headers.set(key, value);
	}

	return new Response(JSON.stringify(data), {
		...init,
		headers
	});
}