// Removed direct use of @google/generative-ai on the client
// and switched to calling backend endpoints that securely use the API key at runtime.

// Keep js-beautify formatting utilities and transformers for compatibility
import { html as formatHtml } from "js-beautify";

export interface ChatMessage {
  role: string;
  content: string;
}

// Helper function to format HTML with proper indentation
const formatCode = (code: string): string => {
  try {
    return formatHtml(code, {
      indent_size: 2,
      indent_char: ' ',
      max_preserve_newlines: 2,
      preserve_newlines: true,
      indent_inner_html: true,
      brace_style: 'collapse',
      indent_scripts: 'normal',
      wrap_line_length: 120,
      unformatted: ['code', 'pre', 'em', 'strong', 'span'],
      content_unformatted: ['pre', 'code'],
    });
  } catch (error) {
    console.error('Error formatting code:', error);
    return code;
  }
};

// Helper function to transform the AI's array response into the object format our app uses.
const transformApiResponse = (response: { files: { fileName: string; code: string }[] }): Record<string, string> => {
  const filesRecord: Record<string, string> = {};
  if (response && (response as any).files && Array.isArray((response as any).files)) {
    for (const file of (response as any).files) {
      if (file.fileName && file.code) {
        filesRecord[file.fileName] = formatCode(file.code);
      }
    }
  }
  return filesRecord;
};

// Normalize server response to the same shape as before
const normalizeResponse = (data: any): Record<string, string> => {
  // If server already returns a Record<string, string>
  if (data && typeof data === 'object' && !Array.isArray(data) && !('files' in data)) {
    return data as Record<string, string>;
  }
  // If server returns { files: [...] }
  if (data && typeof data === 'object' && 'files' in data) {
    return transformApiResponse(data as { files: { fileName: string; code: string }[] });
  }
  // Fallback to empty object
  return {};
};

const handleError = async (res: Response) => {
  let message = 'Unknown error';
  try {
    const body = await res.json();
    if (body && body.error) {
      message = String(body.error);
    }
  } catch {
    // ignore JSON parse errors
    message = res.statusText || message;
  }

  // Preserve prior UX message for missing key to avoid UI changes
  if (message.toLowerCase().includes('gemini api key is not configured')) {
    throw new Error('Gemini API key is not configured. Please set GEMINI_API_KEY in your Hugging Face Space secrets.');
  }

  throw new Error(message);
};

export const generateCode = async (
  messages: ChatMessage[]
): Promise<Record<string, string>> => {
  try {
    const res = await fetch('/api/generate-code', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ messages }),
    });

    if (!res.ok) {
      await handleError(res);
    }

    const data = await res.json();
    return normalizeResponse(data);
  } catch (error) {
    console.error('Error in generateCode:', error);
    throw error;
  }
};

export const modifyCode = async (
  currentFiles: Record<string, string>,
  modificationRequest: string
): Promise<Record<string, string>> => {
  try {
    const res = await fetch('/api/modify-code', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ currentFiles, modificationRequest }),
    });

    if (!res.ok) {
      await handleError(res);
    }

    const data = await res.json();
    return normalizeResponse(data);
  } catch (error) {
    console.error('Error in modifyCode:', error);
    throw error;
  }
};