import { CORS_ORIGIN } from "@/shared/utils/cors";
import { handleImageGeneration } from "@omniroute/open-sse/handlers/imageGeneration.ts";
import { getProviderCredentials, extractApiKey, isValidApiKey } from "@/sse/services/auth";
import { parseImageModel, getAllImageModels, getImageProvider } from "@omniroute/open-sse/config/imageRegistry.ts";
import { errorResponse } from "@omniroute/open-sse/utils/error.ts";
import { HTTP_STATUS } from "@omniroute/open-sse/config/constants.ts";
import * as log from "@/sse/utils/logger";
import { toJsonErrorPayload } from "@/shared/utils/upstreamError";
import { enforceApiKeyPolicy } from "@/shared/utils/apiKeyPolicy";

/**
 * Handle CORS preflight
 */
export async function OPTIONS() {
  return new Response(null, {
    headers: {
      "Access-Control-Allow-Origin": CORS_ORIGIN,
      "Access-Control-Allow-Methods": "GET, POST, OPTIONS",
      "Access-Control-Allow-Headers": "*",
    },
  });
}

/**
 * GET /v1/images/generations — list available image models
 */
export async function GET() {
  const models = getAllImageModels();
  return new Response(
    JSON.stringify({
      object: "list",
      data: models.map((m) => ({
        id: m.id,
        object: "model",
        created: Math.floor(Date.now() / 1000),
        owned_by: m.provider,
        type: "image",
        supported_sizes: m.supportedSizes,
      })),
    }),
    {
      headers: { "Content-Type": "application/json" },
    }
  );
}

/**
 * POST /v1/images/generations — generate images
 */
export async function POST(request) {
  let body;
  try {
    body = await request.json();
  } catch {
    log.warn("IMAGE", "Invalid JSON body");
    return errorResponse(HTTP_STATUS.BAD_REQUEST, "Invalid JSON body");
  }

  // Optional API key validation
  if (process.env.REQUIRE_API_KEY === "true") {
    const apiKey = extractApiKey(request);
    if (!apiKey) {
      return errorResponse(HTTP_STATUS.UNAUTHORIZED, "Missing API key");
    }
    const valid = await isValidApiKey(apiKey);
    if (!valid) {
      return errorResponse(HTTP_STATUS.UNAUTHORIZED, "Invalid API key");
    }
  }

  if (!body.model) {
    return errorResponse(HTTP_STATUS.BAD_REQUEST, "Missing model");
  }

  if (typeof body.prompt !== "string" || body.prompt.trim().length === 0) {
    return errorResponse(HTTP_STATUS.BAD_REQUEST, "Invalid prompt: expected a non-empty string");
  }

  // Enforce API key policies (model restrictions + budget limits)
  const policy = await enforceApiKeyPolicy(request, body.model);
  if (policy.rejection) return policy.rejection;

  // Parse model to get provider
  const { provider } = parseImageModel(body.model);
  if (!provider) {
    return errorResponse(
      HTTP_STATUS.BAD_REQUEST,
      `Invalid image model: ${body.model}. Use format: provider/model`
    );
  }

  // Check provider config for auth bypass
  const providerConfig = getImageProvider(provider);

  // Get credentials — skip for local providers (authType: "none")
  let credentials = null;
  if (providerConfig && providerConfig.authType !== "none") {
    credentials = await getProviderCredentials(provider);
    if (!credentials) {
      return errorResponse(HTTP_STATUS.BAD_REQUEST, `No credentials for image provider: ${provider}`);
    }
  }

  const result = await handleImageGeneration({ body, credentials, log });

  if (result.success) {
    return new Response(JSON.stringify((result as any).data), {
      status: 200,
      headers: { "Content-Type": "application/json" },
    });
  }

  const errorPayload = toJsonErrorPayload((result as any).error, "Image generation provider error");
  return new Response(JSON.stringify(errorPayload), {
    status: (result as any).status,
    headers: { "Content-Type": "application/json" },
  });
}
