import { useState } from 'react'
import { Link, useNavigate } from 'react-router-dom'
import { useForm } from 'react-hook-form'
import { zodResolver } from '@hookform/resolvers/zod'
import { z } from 'zod'
import { useAuthStore } from '@/store/auth'
import { marathonsApi } from '@/api'
import { NeonButton, Input, GlassCard } from '@/components/ui'
import { Gamepad2, LogIn, AlertCircle, Trophy, Users, Zap, Target, Shield, ArrowLeft } from 'lucide-react'

const loginSchema = z.object({
  login: z.string().min(3, 'Логин должен быть не менее 3 символов'),
  password: z.string().min(6, 'Пароль должен быть не менее 6 символов'),
})

type LoginForm = z.infer<typeof loginSchema>

export function LoginPage() {
  const navigate = useNavigate()
  const { login, verify2FA, cancel2FA, pending2FA, isLoading, error, clearError, consumePendingInviteCode } = useAuthStore()
  const [submitError, setSubmitError] = useState<string | null>(null)
  const [twoFACode, setTwoFACode] = useState('')

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

  const onSubmit = async (data: LoginForm) => {
    setSubmitError(null)
    clearError()
    try {
      const result = await login(data)

      // If 2FA required, don't navigate
      if (result.requires2FA) {
        return
      }

      // Check for pending invite code
      const pendingCode = consumePendingInviteCode()
      if (pendingCode) {
        try {
          const marathon = await marathonsApi.join(pendingCode)
          navigate(`/marathons/${marathon.id}`)
          return
        } catch {
          // If join fails (already member, etc), just go to marathons
        }
      }

      navigate('/marathons')
    } catch {
      // Error is already set in store by login function
      // Ban case is handled separately via banInfo state
    }
  }

  const handle2FASubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    setSubmitError(null)
    clearError()
    try {
      await verify2FA(twoFACode)
      navigate('/marathons')
    } catch {
      setSubmitError(error || 'Неверный код')
    }
  }

  const handleCancel2FA = () => {
    cancel2FA()
    setTwoFACode('')
    setSubmitError(null)
  }

  const features = [
    { icon: <Trophy className="w-5 h-5" />, text: 'Соревнуйтесь с друзьями' },
    { icon: <Target className="w-5 h-5" />, text: 'Выполняйте челленджи' },
    { icon: <Zap className="w-5 h-5" />, text: 'Зарабатывайте очки' },
    { icon: <Users className="w-5 h-5" />, text: 'Создавайте марафоны' },
  ]

  return (
    <div className="min-h-[80vh] flex items-center justify-center px-4 -mt-8">
      {/* Background effects */}
      <div className="fixed inset-0 overflow-hidden pointer-events-none">
        <div className="absolute top-1/4 -left-32 w-96 h-96 bg-neon-500/10 rounded-full blur-[100px]" />
        <div className="absolute bottom-1/4 -right-32 w-96 h-96 bg-accent-500/10 rounded-full blur-[100px]" />
      </div>

      {/* Bento Grid */}
      <div className="relative w-full max-w-4xl">
        <div className="grid grid-cols-1 md:grid-cols-2 gap-4 animate-scale-in">
          {/* Branding Block (left) */}
          <GlassCard className="p-8 flex flex-col justify-center relative overflow-hidden" variant="neon">
            {/* Background decoration */}
            <div className="absolute inset-0 overflow-hidden pointer-events-none">
              <div className="absolute -top-20 -left-20 w-48 h-48 bg-neon-500/20 rounded-full blur-[60px]" />
              <div className="absolute -bottom-20 -right-20 w-48 h-48 bg-accent-500/20 rounded-full blur-[60px]" />
            </div>

            <div className="relative">
              {/* Logo */}
              <div className="flex justify-center md:justify-start mb-6">
                <div className="w-20 h-20 rounded-2xl bg-neon-500/10 border border-neon-500/30 flex items-center justify-center shadow-[0_0_24px_rgba(34,211,238,0.25)]">
                  <Gamepad2 className="w-10 h-10 text-neon-500" />
                </div>
              </div>

              {/* Title */}
              <h1 className="text-3xl md:text-4xl font-bold text-white mb-2 text-center md:text-left">
                Game Marathon
              </h1>
              <p className="text-gray-400 mb-8 text-center md:text-left">
                Платформа для игровых соревнований
              </p>

              {/* Features */}
              <div className="grid grid-cols-2 gap-3">
                {features.map((feature, index) => (
                  <div
                    key={index}
                    className="flex items-center gap-2 p-3 rounded-xl bg-dark-700/50 border border-dark-600"
                  >
                    <div className="w-8 h-8 rounded-lg bg-neon-500/20 flex items-center justify-center text-neon-400">
                      {feature.icon}
                    </div>
                    <span className="text-sm text-gray-300">{feature.text}</span>
                  </div>
                ))}
              </div>
            </div>
          </GlassCard>

          {/* Form Block (right) */}
          <GlassCard className="p-8">
            {pending2FA ? (
              // 2FA Form
              <>
                {/* Header */}
                <div className="text-center mb-8">
                  <div className="w-16 h-16 mx-auto mb-4 rounded-2xl bg-neon-500/10 border border-neon-500/30 flex items-center justify-center">
                    <Shield className="w-8 h-8 text-neon-500" />
                  </div>
                  <h2 className="text-2xl font-bold text-white mb-2">Двухфакторная аутентификация</h2>
                  <p className="text-gray-400">Введите код из Telegram</p>
                </div>

                {/* 2FA Form */}
                <form onSubmit={handle2FASubmit} className="space-y-5">
                  {(submitError || error) && (
                    <div className="flex items-center gap-3 p-4 bg-red-500/10 border border-red-500/30 rounded-xl text-red-400 text-sm animate-shake">
                      <AlertCircle className="w-5 h-5 flex-shrink-0" />
                      <span>{submitError || error}</span>
                    </div>
                  )}

                  <Input
                    label="Код подтверждения"
                    placeholder="000000"
                    value={twoFACode}
                    onChange={(e) => setTwoFACode(e.target.value.replace(/\D/g, '').slice(0, 6))}
                    maxLength={6}
                    className="text-center text-2xl tracking-widest font-mono"
                    autoFocus
                  />

                  <NeonButton
                    type="submit"
                    className="w-full"
                    size="lg"
                    isLoading={isLoading}
                    disabled={twoFACode.length !== 6}
                    icon={<Shield className="w-5 h-5" />}
                  >
                    Подтвердить
                  </NeonButton>
                </form>

                {/* Back button */}
                <div className="mt-6 pt-6 border-t border-dark-600 text-center">
                  <button
                    onClick={handleCancel2FA}
                    className="text-gray-400 hover:text-white transition-colors text-sm flex items-center justify-center gap-2 mx-auto"
                  >
                    <ArrowLeft className="w-4 h-4" />
                    Вернуться к входу
                  </button>
                </div>
              </>
            ) : (
              // Regular Login Form
              <>
                {/* Header */}
                <div className="text-center mb-8">
                  <h2 className="text-2xl font-bold text-white mb-2">Добро пожаловать!</h2>
                  <p className="text-gray-400">Войдите, чтобы продолжить</p>
                </div>

                {/* Form */}
                <form onSubmit={handleSubmit(onSubmit)} className="space-y-5">
                  {(submitError || error) && (
                    <div className="flex items-center gap-3 p-4 bg-red-500/10 border border-red-500/30 rounded-xl text-red-400 text-sm animate-shake">
                      <AlertCircle className="w-5 h-5 flex-shrink-0" />
                      <span>{submitError || error}</span>
                    </div>
                  )}

                  <Input
                    label="Логин"
                    placeholder="Введите логин"
                    error={errors.login?.message}
                    autoComplete="username"
                    {...register('login')}
                  />

                  <Input
                    label="Пароль"
                    type="password"
                    placeholder="Введите пароль"
                    error={errors.password?.message}
                    autoComplete="current-password"
                    {...register('password')}
                  />

                  <NeonButton
                    type="submit"
                    className="w-full"
                    size="lg"
                    isLoading={isLoading}
                    icon={<LogIn className="w-5 h-5" />}
                  >
                    Войти
                  </NeonButton>
                </form>

                {/* Footer */}
                <div className="mt-6 pt-6 border-t border-dark-600 text-center">
                  <p className="text-gray-400 text-sm">
                    Нет аккаунта?{' '}
                    <Link
                      to="/register"
                      className="text-neon-400 hover:text-neon-300 transition-colors font-medium"
                    >
                      Зарегистрироваться
                    </Link>
                  </p>
                </div>
              </>
            )}
          </GlassCard>
        </div>

        {/* Decorative elements */}
        <div className="absolute -top-4 -right-4 w-24 h-24 border border-neon-500/20 rounded-2xl -z-10 hidden md:block" />
        <div className="absolute -bottom-4 -left-4 w-32 h-32 border border-accent-500/20 rounded-2xl -z-10 hidden md:block" />
      </div>
    </div>
  )
}