'use client'

import { useState } from 'react'
import { useLocale, useTranslations } from 'next-intl'
import { createClient } from '@/lib/supabase/client'
import { Button } from '@/components/ui/button'
import { Loader2 } from 'lucide-react'
import { getErrorMessage, type ErrorLocale } from '@/lib/errors/get-error-message'

/** Official Google "G" mark, drawn inline (no external assets on auth pages). */
function GoogleMark() {
  return (
    <svg viewBox="0 0 48 48" aria-hidden className="h-4 w-4">
      <path
        fill="#EA4335"
        d="M24 9.5c3.54 0 6.71 1.22 9.21 3.6l6.85-6.85C35.9 2.38 30.47 0 24 0 14.62 0 6.51 5.38 2.56 13.22l7.98 6.19C12.43 13.72 17.74 9.5 24 9.5z"
      />
      <path
        fill="#4285F4"
        d="M46.98 24.55c0-1.57-.15-3.09-.38-4.55H24v9.02h12.94c-.58 2.96-2.26 5.48-4.78 7.18l7.73 6c4.51-4.18 7.09-10.36 7.09-17.65z"
      />
      <path
        fill="#FBBC05"
        d="M10.53 28.59c-.48-1.45-.76-2.99-.76-4.59s.27-3.14.76-4.59l-7.98-6.19C.92 16.46 0 20.12 0 24c0 3.88.92 7.54 2.56 10.78l7.97-6.19z"
      />
      <path
        fill="#34A853"
        d="M24 48c6.48 0 11.93-2.13 15.89-5.81l-7.73-6c-2.15 1.45-4.92 2.3-8.16 2.3-6.26 0-11.57-4.22-13.47-9.91l-7.98 6.19C6.51 42.62 14.62 48 24 48z"
      />
    </svg>
  )
}

/**
 * "Continue with Google" for the login and register pages.
 *
 * Kicks off the Supabase OAuth redirect; the round-trip lands in
 * /auth/callback (PKCE code exchange), which owns MFA routing, invite
 * acceptance and silent-team creation for OAuth sign-ins and sign-ups alike.
 * The flow=oauth marker lets the callback tag failures so the login page
 * shows Google-specific copy instead of the email-confirmation framing.
 */
export function GoogleAuthButton({
  onError,
  compact = false,
}: {
  onError: (message: string) => void
  /**
   * Half-width alternative-method chip on the login panel: shows just the
   * mark and "Google" (a brand name, never translated), with the full label
   * kept as the accessible name.
   */
  compact?: boolean
}) {
  const [isRedirecting, setIsRedirecting] = useState(false)
  const supabase = createClient()
  const tAuth = useTranslations('auth')
  const errorLocale = useLocale() as ErrorLocale

  const handleClick = async () => {
    setIsRedirecting(true)
    try {
      const { error } = await supabase.auth.signInWithOAuth({
        provider: 'google',
        options: {
          redirectTo: `${window.location.origin}/auth/callback?flow=oauth`,
        },
      })
      if (error) {
        onError(getErrorMessage(error, { context: 'auth', locale: errorLocale }))
        setIsRedirecting(false)
      }
      // On success the browser navigates away; keep the spinner until then.
    } catch (error) {
      onError(getErrorMessage(error, { context: 'auth', locale: errorLocale }))
      setIsRedirecting(false)
    }
  }

  return (
    <Button
      type="button"
      variant="outline"
      className={compact ? 'h-10 w-full gap-2' : 'w-full h-11'}
      onClick={handleClick}
      disabled={isRedirecting}
      aria-label={tAuth('continue_with_google')}
    >
      {isRedirecting ? (
        <Loader2 className={compact ? 'h-4 w-4 animate-spin' : 'mr-2 h-4 w-4 animate-spin'} />
      ) : (
        <span className={compact ? 'flex items-center' : 'mr-2 flex items-center'}>
          <GoogleMark />
        </span>
      )}
      {compact ? 'Google' : tAuth('continue_with_google')}
    </Button>
  )
}