'use client';

import * as React from 'react';
import { useRouter, useSearchParams } from 'next/navigation';
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import Image from 'next/image';
import { useAuth } from '@/lib/auth/auth-context';
import { useTenantTheme, TenantThemeProvider } from '@/lib/theme/theme-provider';
import { ApiError } from '@/lib/api/client';
import { loginSchema, type LoginFormValues } from '@/lib/validators/auth';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { FormField } from '@/components/ui/form-field';
import Link from 'next/link';

type LoginArea = 'tenant' | 'master';

function GenericInvalidCredentialsMessage(): string {
  return 'E-mail ou senha inválidos.';
}

function LoginFormInner() {
  const router = useRouter();
  const searchParams = useSearchParams();
  const { loginMaster, loginTenant } = useAuth();
  const { theme } = useTenantTheme();

  // Estratégia de detecção de tipo de login (Etapa 13): o backend expõe
  // dois endpoints separados (`/auth/master/login` e `/auth/tenant/login`,
  // sem detecção automática por e-mail — ver observações da Etapa 13 no
  // controle de progresso). Escolhido um toggle explícito em vez de dois
  // formulários separados por ser a opção mais simples de implementar e
  // mais clara para o usuário; "tenant" é o padrão porque é o público
  // majoritário (clientes), master é uso interno raro.
  const [area, setArea] = React.useState<LoginArea>('tenant');
  const [submitError, setSubmitError] = React.useState<string | null>(null);

  const {
    register,
    handleSubmit,
    formState: { errors, isSubmitting },
  } = useForm<LoginFormValues>({ resolver: zodResolver(loginSchema) });

  const onSubmit = async (values: LoginFormValues) => {
    setSubmitError(null);
    try {
      if (area === 'master') {
        await loginMaster(values.email, values.senha);
      } else {
        await loginTenant(values.email, values.senha);
      }

      const redirectParam = searchParams.get('redirect');
      const fallback = area === 'master' ? '/master/dashboard' : '/app/dashboard';
      router.push(redirectParam && redirectParam.startsWith('/') ? redirectParam : fallback);
    } catch (err) {
      if (err instanceof ApiError && err.statusCode === 401) {
        setSubmitError(GenericInvalidCredentialsMessage());
      } else if (err instanceof ApiError) {
        setSubmitError(err.message);
      } else {
        setSubmitError('Não foi possível conectar. Tente novamente.');
      }
    }
  };

  return (
    <div className="flex w-full max-w-[420px] flex-col gap-6 rounded-xl border border-border bg-surface p-6 shadow-sm sm:p-8">
      <div className="flex flex-col items-center gap-2 text-center">
        {theme?.logoUrl ? (
          <Image
            src={theme.logoUrl}
            alt={theme.nome}
            width={48}
            height={48}
            className="size-12 rounded-lg object-contain"
          />
        ) : null}
        <h1 className="text-xl font-semibold text-foreground">
          {theme?.nome ?? 'SeConectai Vendas'}
        </h1>
        <p className="text-sm text-muted-foreground">Entre com seu e-mail e senha</p>
      </div>

      <div
        role="radiogroup"
        aria-label="Tipo de acesso"
        className="grid grid-cols-2 gap-1 rounded-lg bg-muted p-1"
      >
        <button
          type="button"
          role="radio"
          aria-checked={area === 'tenant'}
          onClick={() => setArea('tenant')}
          className={`min-h-9 rounded-md text-sm font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-ring ${
            area === 'tenant' ? 'bg-background text-foreground shadow-sm' : 'text-muted-foreground'
          }`}
        >
          Sou cliente
        </button>
        <button
          type="button"
          role="radio"
          aria-checked={area === 'master'}
          onClick={() => setArea('master')}
          className={`min-h-9 rounded-md text-sm font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-ring ${
            area === 'master' ? 'bg-background text-foreground shadow-sm' : 'text-muted-foreground'
          }`}
        >
          Sou administrador
        </button>
      </div>

      <form className="flex flex-col gap-4" onSubmit={handleSubmit(onSubmit)} noValidate>
        <FormField label="E-mail" error={errors.email?.message}>
          <Input type="email" autoComplete="email" {...register('email')} />
        </FormField>
        <FormField label="Senha" error={errors.senha?.message}>
          <Input type="password" autoComplete="current-password" {...register('senha')} />
        </FormField>

        {submitError && (
          <p role="alert" className="rounded-lg bg-danger/10 p-3 text-sm text-danger">
            {submitError}
          </p>
        )}

        <Button type="submit" loading={isSubmitting} className="w-full">
          Entrar
        </Button>

        <Link
          href="/esqueci-senha"
          className="text-center text-sm text-primary-on-light underline-offset-4 hover:underline"
        >
          Esqueci minha senha
        </Link>
      </form>
    </div>
  );
}

export function LoginForm() {
  const searchParams = useSearchParams();
  const tenantId = searchParams.get('tenant');

  return (
    <TenantThemeProvider tenantId={tenantId}>
      <LoginFormInner />
    </TenantThemeProvider>
  );
}