import { createClient } from '@supabase/supabase-js';

const createSupabaseClient = () => {
  const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL;
  const supabaseAnonKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY;

  if (typeof window === 'undefined') { // Server-side or build process
    if (!supabaseUrl || !supabaseAnonKey) {
      console.log('Build/SSR: Supabase URL or Anon Key is missing. Client not initialized.');
      return null;
    }
    // If URL and Key are present, try to create client but catch errors during build
    try {
      const client = createClient(supabaseUrl, supabaseAnonKey);
      // console.log('Build/SSR: Supabase client potentially initialized with provided credentials.'); // Less verbose
      return client;
    } catch (error) {
      console.warn(`Build/SSR: Error initializing Supabase client with provided credentials: ${error.message}. This might be due to invalid credentials or network issues during build. App will attempt to connect at runtime.`);
      return null; // Prevent build failure if client creation itself errors with valid-looking but problematic creds
    }
  } else { // Client-side (browser)
    if (!supabaseUrl || !supabaseAnonKey) {
      console.warn('Client-side: Supabase URL or Anon Key is missing. Please check environment variables.');
      return null;
    }
    try {
      return createClient(supabaseUrl, supabaseAnonKey);
    } catch (error) {
      console.error(`Client-side: Error initializing Supabase client: ${error.message}`);
      return null;
    }
  }
};

export const supabase = createSupabaseClient();

export const safeQuery = async (queryFn) => {
  if (!supabase) {
    const buildTimeMessage = 'Build time: Supabase client not initialized for pre-rendering, due to missing or problematic credentials.';
    const runTimeMessage = 'Runtime: Supabase client not available. Check environment variables and connection.';
    
    // Check if this is build time (Node.js environment during `next build`)
    if (typeof window === 'undefined' && process.env.NODE_ENV === 'production') {
        console.log(buildTimeMessage);
        return { data: null, error: { message: 'Supabase not available during build.' } };
    } else {
        console.warn(runTimeMessage);
        return { data: null, error: { message: 'Supabase connection not available.' } };
    }
  }
  
  try {
    const result = await queryFn(supabase);
    // Add a check for Supabase-specific errors if the query executes but returns an error object
    if (result.error) {
      console.error('Supabase query error:', result.error.message);
      // Return a consistent error structure
      return { data: null, error: { message: result.error.message } }; 
    }
    return result;
  } catch (error) {
    // Catch unexpected errors during the queryFn execution itself
    console.error('Unexpected error in Supabase query function:', error.message);
    return { data: null, error: { message: `Unexpected error during database operation: ${error.message}` } };
  }
};