import { createClient, type SupabaseClient } from '@supabase/supabase-js'

const supabaseUrl = import.meta.env['VITE_SUPABASE_URL'] ?? ''
const supabaseAnonKey = import.meta.env['VITE_SUPABASE_ANON_KEY'] ?? ''
const isLocalDev = supabaseUrl.includes('localhost')

// supabase-js hardcodes /auth/v1 as the auth path prefix, but GoTrue
// serves at the root when accessed directly (no API gateway).
// This custom fetch strips the prefix for local dev.
function localGoTrueFetch(input: RequestInfo | URL, init?: RequestInit): Promise<Response> {
  const url = input instanceof Request ? input.url : String(input)
  const rewritten = url.replace('/auth/v1/', '/')
  if (input instanceof Request) {
    return fetch(new Request(rewritten, input), init)
  }
  return fetch(rewritten, init)
}

function createSupabaseClient(): SupabaseClient {
  if (!supabaseUrl || !supabaseAnonKey) {
    return createClient('http://localhost:9999', 'stub-key')
  }
  return createClient(supabaseUrl, supabaseAnonKey, {
    auth: {
      autoRefreshToken: true,
      persistSession: true,
    },
    ...(isLocalDev && {
      global: { fetch: localGoTrueFetch },
    }),
  })
}

export const supabase = createSupabaseClient()