'use client';

import { useState, useEffect } from 'react';
import { signIn } from 'next-auth/react';
import { useRouter, useSearchParams } from 'next/navigation';
import { Eye, EyeOff } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from '@/components/ui/dialog';
import Link from 'next/link';
import { ForgotPasswordDialog } from '@/components/ForgotPasswordDialog';

interface LoginDialogProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  onSuccess?: () => void;
  onOpenRegister?: () => void;
  callbackUrl?: string;
  registered?: boolean;
}

export function LoginDialog({
  open,
  onOpenChange,
  onSuccess,
  onOpenRegister,
  callbackUrl: initialCallbackUrl,
  registered: initialRegistered,
}: LoginDialogProps) {
  const router = useRouter();
  const searchParams = useSearchParams();
  const callbackUrl = initialCallbackUrl || searchParams.get('callbackUrl') || '/';
  const registered = initialRegistered || searchParams.get('registered') === 'true';
  
  const [email, setEmail] = useState('');
  const [password, setPassword] = useState('');
  const [error, setError] = useState('');
  const [emailNotVerified, setEmailNotVerified] = useState(false);
  const [isLoading, setIsLoading] = useState(false);
  const [isResending, setIsResending] = useState(false);
  const [forgotPasswordOpen, setForgotPasswordOpen] = useState(false);
  const [showPassword, setShowPassword] = useState(false);

  // Reset all form state when dialog opens
  useEffect(() => {
    if (open) {
      setEmail('');
      setPassword('');
      setError('');
      setEmailNotVerified(false);
      setIsLoading(false);
      setIsResending(false);
      setShowPassword(false);
    }
  }, [open]);

  const handleResendConfirmation = async () => {
    setIsResending(true);
    try {
      const response = await fetch('/api/auth/resend-confirmation', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ email }),
      });
      const data = await response.json();
      if (response.ok) {
        setError('');
        setEmailNotVerified(false);
        alert('Confirmation email sent! Please check your inbox.');
      } else {
        alert(data.error || 'Failed to resend confirmation email');
      }
    } catch (err) {
      alert('An error occurred. Please try again.');
    } finally {
      setIsResending(false);
    }
  };

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    setError('');
    setEmailNotVerified(false);
    setIsLoading(true);

    try {
      // First check if email is verified
      const checkResponse = await fetch('/api/auth/check-verification', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ email, password }),
      });
      const checkData = await checkResponse.json();

      if (!checkData.exists) {
        setError('Invalid email or password');
        setIsLoading(false);
        return;
      }

      if (!checkData.passwordValid) {
        setError('Invalid email or password');
        setIsLoading(false);
        return;
      }

      if (!checkData.verified) {
        setEmailNotVerified(true);
        setIsLoading(false);
        return;
      }

      // Email is verified, proceed with login
      const result = await signIn('credentials', {
        email,
        password,
        redirect: false,
      });

      if (result?.error) {
        setError('Invalid email or password');
      } else {
        onOpenChange(false);
        if (onSuccess) {
          onSuccess();
        } else {
          router.push(callbackUrl);
          router.refresh();
        }
      }
    } catch (err) {
      setError('An error occurred. Please try again.');
    } finally {
      setIsLoading(false);
    }
  };

  const handleOpenChange = (newOpen: boolean) => {
    if (!newOpen) {
      // Reset form when closing
      setEmail('');
      setPassword('');
      setError('');
      setEmailNotVerified(false);
      setIsResending(false);
    }
    onOpenChange(newOpen);
  };

  return (
    <Dialog open={open} onOpenChange={handleOpenChange}>
      <DialogContent className="sm:max-w-md">
        <DialogHeader>
          <DialogTitle>Sign in to your account</DialogTitle>
          <DialogDescription>
            Or{' '}
            {onOpenRegister ? (
              <button
                type="button"
                className="font-medium text-secondary hover:text-secondary/80"
                onClick={() => {
                  handleOpenChange(false);
                  onOpenRegister();
                }}
              >
                create a new account
              </button>
            ) : (
              <Link
                href="/register"
                className="font-medium text-secondary hover:text-secondary/80"
                onClick={() => handleOpenChange(false)}
              >
                create a new account
              </Link>
            )}
          </DialogDescription>
        </DialogHeader>
        <form onSubmit={handleSubmit} className="space-y-4">
          {registered && (
            <div className="rounded-md bg-green-50 p-4 dark:bg-green-900/20">
              <p className="text-sm text-green-800 dark:text-green-200">
                Account created successfully! Please check your email to confirm your account before signing in.
              </p>
            </div>
          )}
          {searchParams.get('verified') === 'true' && (
            <div className="rounded-md bg-green-50 p-4 dark:bg-green-900/20">
              <p className="text-sm text-green-800 dark:text-green-200">
                Email verified successfully! You can now sign in.
              </p>
            </div>
          )}
          {emailNotVerified && (
            <div className="rounded-md bg-yellow-50 p-4 dark:bg-yellow-900/20">
              <p className="text-sm text-yellow-800 dark:text-yellow-200 mb-2">
                Please verify your email address before signing in. Check your inbox for a confirmation email.
              </p>
              <button
                type="button"
                onClick={handleResendConfirmation}
                disabled={isResending}
                className="text-sm text-yellow-900 dark:text-yellow-100 underline hover:no-underline font-medium"
              >
                {isResending ? 'Sending...' : 'Resend confirmation email'}
              </button>
            </div>
          )}
          {error && (
            <div className="rounded-md bg-red-50 p-4 dark:bg-red-900/20">
              <p className="text-sm text-red-800 dark:text-red-200">{error}</p>
            </div>
          )}
          <div className="space-y-4">
            <div>
              <label htmlFor="email" className="block text-sm font-medium text-secondary dark:text-gray-300">
                Email address
              </label>
              <Input
                id="email"
                name="email"
                type="email"
                autoComplete="email"
                required
                value={email}
                onChange={(e) => {
                  setEmail(e.target.value);
                  // Clear email verification error when email changes
                  if (emailNotVerified) {
                    setEmailNotVerified(false);
                  }
                }}
                className="mt-1"
                placeholder="you@example.com"
              />
            </div>
            <div>
              <div className="flex items-center justify-between">
                <label htmlFor="password" className="block text-sm font-medium text-secondary dark:text-gray-300">
                  Password
                </label>
                <button
                  type="button"
                  onClick={() => {
                    setForgotPasswordOpen(true);
                  }}
                  className="text-sm text-secondary hover:text-secondary/80 font-medium"
                >
                  Forgot password?
                </button>
              </div>
              <div className="relative mt-1">
                <Input
                  id="password"
                  name="password"
                  type={showPassword ? 'text' : 'password'}
                  autoComplete="current-password"
                  required
                  value={password}
                  onChange={(e) => setPassword(e.target.value)}
                  className="pr-10"
                  placeholder="••••••••"
                />
                <button
                  type="button"
                  onClick={() => setShowPassword(!showPassword)}
                  className="absolute right-3 top-1/2 -translate-y-1/2 text-secondary hover:text-secondary/80 focus:outline-none"
                  aria-label={showPassword ? 'Hide password' : 'Show password'}
                >
                  {showPassword ? (
                    <EyeOff className="h-4 w-4" />
                  ) : (
                    <Eye className="h-4 w-4" />
                  )}
                </button>
              </div>
            </div>
          </div>
          <DialogFooter>
            <Button
              type="submit"
              className="w-full"
              disabled={isLoading}
            >
              {isLoading ? 'Signing in...' : 'Sign in'}
            </Button>
          </DialogFooter>
        </form>
      </DialogContent>
      <ForgotPasswordDialog
        open={forgotPasswordOpen}
        onOpenChange={setForgotPasswordOpen}
      />
    </Dialog>
  );
}