"use client";

import { useState } from "react";
import { useAuth } from "@/lib/auth-context";
import { useRouter } from "next/navigation";
import Link from "next/link";
import type { AxiosError } from "axios";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import {
  Card,
  CardContent,
  CardFooter,
} from "@/components/ui/card";
import { Separator } from "@/components/ui/separator";
import { Shield, ArrowLeft } from "lucide-react";

export default function LoginPage() {
  const { login, twoFactorChallenge, verifyTwoFactor, cancelTwoFactor } = useAuth();
  const router = useRouter();
  const [email, setEmail] = useState("");
  const [password, setPassword] = useState("");
  const [error, setError] = useState("");
  const [isLoading, setIsLoading] = useState(false);
  const [twoFactorCode, setTwoFactorCode] = useState("");

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

    try {
      await login({ email, password });
      if (!twoFactorChallenge) {
        router.push("/dashboard");
      }
    } catch (err) {
      const axiosError = err as AxiosError<{
        message?: string;
        errors?: Record<string, string[]>;
      }>;
      if (axiosError.response?.data?.errors) {
        const messages = Object.values(axiosError.response.data.errors).flat();
        setError(messages.join(" "));
      } else if (axiosError.response?.data?.message) {
        setError(axiosError.response.data.message);
      } else {
        setError("An error occurred. Please try again.");
      }
    } finally {
      setIsLoading(false);
    }
  };

  const handleTwoFactorSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    setError("");
    setIsLoading(true);

    try {
      await verifyTwoFactor(twoFactorCode);
      router.push("/dashboard");
    } catch (err) {
      const axiosError = err as AxiosError<{ message?: string }>;
      setError(axiosError.response?.data?.message || "Invalid verification code.");
    } finally {
      setIsLoading(false);
    }
  };

  // 2FA Verification Screen
  if (twoFactorChallenge) {
    return (
      <div className="flex min-h-full flex-1 items-center justify-center bg-background px-4 py-12">
        <div className="w-full max-w-sm">
          <div className="mb-8 text-center">
            <div className="mx-auto flex h-12 w-12 items-center justify-center rounded-full bg-primary/10">
              <Shield className="h-6 w-6 text-primary" />
            </div>
            <h1 className="mt-4 font-display text-2xl text-foreground">
              Two-Factor Authentication
            </h1>
            <p className="mt-1 text-sm text-muted-foreground">
              {twoFactorChallenge.method === 'email'
                ? 'Enter the 4-digit code sent to your email.'
                : 'Enter the 6-digit code from your authenticator app.'}
            </p>
          </div>

          <Card>
            <CardContent className="pt-6">
              {error && (
                <div className="mb-4 rounded-lg border border-destructive/20 bg-destructive/5 px-4 py-3 text-sm text-destructive">
                  {error}
                </div>
              )}

              <form onSubmit={handleTwoFactorSubmit} className="space-y-4">
                <div className="space-y-2">
                  <Label htmlFor="code">Verification Code</Label>
                  <Input
                    id="code"
                    type="text"
                    inputMode="numeric"
                    autoComplete="one-time-code"
                    placeholder={twoFactorChallenge.method === 'email' ? '0000' : '000000'}
                    maxLength={twoFactorChallenge.method === 'email' ? 4 : 6}
                    value={twoFactorCode}
                    onChange={(e) => setTwoFactorCode(e.target.value.replace(/\D/g, ''))}
                    className="text-center text-lg tracking-widest"
                  />
                </div>

                <Button
                  type="submit"
                  disabled={isLoading}
                  className="w-full"
                  size="lg"
                >
                  {isLoading ? "Verifying..." : "Verify"}
                </Button>
              </form>

              <p className="mt-4 text-center text-xs text-muted-foreground">
                You can also use a recovery code.
              </p>
            </CardContent>
            <CardFooter className="justify-center border-t border-border py-4">
              <Button
                variant="ghost"
                size="sm"
                onClick={() => {
                  cancelTwoFactor();
                  setTwoFactorCode("");
                  setError("");
                }}
              >
                <ArrowLeft className="mr-2 h-4 w-4" />
                Back to login
              </Button>
            </CardFooter>
          </Card>
        </div>
      </div>
    );
  }

  return (
    <div className="flex min-h-full flex-1 items-center justify-center bg-background px-4 py-12">
      <div className="w-full max-w-sm">
        {/* Logo */}
        <div className="mb-8 text-center">
          <Link href="/" className="inline-flex items-center gap-2">
            <div className="flex h-10 w-10 items-center justify-center rounded-lg bg-primary">
              <span className="font-display text-base text-primary-foreground">
                DP
              </span>
            </div>
          </Link>
          <h1 className="mt-4 font-display text-2xl text-foreground">
            Welcome back
          </h1>
          <p className="mt-1 text-sm text-muted-foreground">
            Sign in to your Diaspora Property account
          </p>
        </div>

        <Card>
          <CardContent className="pt-6">
            {error && (
              <div className="mb-4 rounded-lg border border-destructive/20 bg-destructive/5 px-4 py-3 text-sm text-destructive">
                {error}
              </div>
            )}

            <form onSubmit={handleSubmit} className="space-y-4">
              <div className="space-y-2">
                <Label htmlFor="email">Email address</Label>
                <Input
                  id="email"
                  type="email"
                  required
                  autoComplete="email"
                  placeholder="you@example.com"
                  value={email}
                  onChange={(e) => setEmail(e.target.value)}
                />
              </div>

              <div className="space-y-2">
                <div className="flex items-center justify-between">
                  <Label htmlFor="password">Password</Label>
                  <Link
                    href="/forgot-password"
                    className="text-xs text-primary hover:text-primary/80"
                  >
                    Forgot password?
                  </Link>
                </div>
                <Input
                  id="password"
                  type="password"
                  required
                  autoComplete="current-password"
                  placeholder="••••••••"
                  value={password}
                  onChange={(e) => setPassword(e.target.value)}
                />
              </div>

              <Button
                type="submit"
                disabled={isLoading}
                className="w-full"
                size="lg"
              >
                {isLoading ? "Signing in..." : "Sign in"}
              </Button>
            </form>

            <div className="relative my-6">
              <Separator />
              <span className="absolute left-1/2 top-1/2 -translate-x-1/2 -translate-y-1/2 bg-card px-3 text-xs text-muted-foreground">
                or continue with
              </span>
            </div>

            <div className="grid grid-cols-2 gap-3">
              <Button variant="outline" asChild className="w-full">
                <a
                  href={`${process.env.NEXT_PUBLIC_API_URL}/api/auth/google/redirect`}
                >
                  <svg className="mr-2 h-4 w-4" viewBox="0 0 24 24">
                    <path
                      d="M22.56 12.25c0-.78-.07-1.53-.2-2.25H12v4.26h5.92c-.26 1.37-1.04 2.53-2.21 3.31v2.77h3.57c2.08-1.92 3.28-4.74 3.28-8.09z"
                      fill="#4285F4"
                    />
                    <path
                      d="M12 23c2.97 0 5.46-.98 7.28-2.66l-3.57-2.77c-.98.66-2.23 1.06-3.71 1.06-2.86 0-5.29-1.93-6.16-4.53H2.18v2.84C3.99 20.53 7.7 23 12 23z"
                      fill="#34A853"
                    />
                    <path
                      d="M5.84 14.09c-.22-.66-.35-1.36-.35-2.09s.13-1.43.35-2.09V7.07H2.18C1.43 8.55 1 10.22 1 12s.43 3.45 1.18 4.93l2.85-2.22.81-.62z"
                      fill="#FBBC05"
                    />
                    <path
                      d="M12 5.38c1.62 0 3.06.56 4.21 1.64l3.15-3.15C17.45 2.09 14.97 1 12 1 7.7 1 3.99 3.47 2.18 7.07l3.66 2.84c.87-2.6 3.3-4.53 6.16-4.53z"
                      fill="#EA4335"
                    />
                  </svg>
                  Google
                </a>
              </Button>
              <Button variant="outline" asChild className="w-full">
                <a
                  href={`${process.env.NEXT_PUBLIC_API_URL}/api/auth/facebook/redirect`}
                >
                  <svg
                    className="mr-2 h-4 w-4 text-[#1877F2]"
                    fill="currentColor"
                    viewBox="0 0 24 24"
                  >
                    <path d="M24 12.073c0-6.627-5.373-12-12-12s-12 5.373-12 12c0 5.99 4.388 10.954 10.125 11.854v-8.385H7.078v-3.47h3.047V9.43c0-3.007 1.792-4.669 4.533-4.669 1.312 0 2.686.235 2.686.235v2.953H15.83c-1.491 0-1.956.925-1.956 1.874v2.25h3.328l-.532 3.47h-2.796v8.385C19.612 23.027 24 18.062 24 12.073z" />
                  </svg>
                  Facebook
                </a>
              </Button>
            </div>
          </CardContent>
          <CardFooter className="justify-center border-t border-border py-4">
            <p className="text-sm text-muted-foreground">
              Don&apos;t have an account?{" "}
              <Link
                href="/register"
                className="font-medium text-primary hover:text-primary/80"
              >
                Create one
              </Link>
            </p>
          </CardFooter>
        </Card>
      </div>
    </div>
  );
}