"use client";

import Link from "next/link";
import { useRouter } from "next/navigation";
import { useState } from "react";
import { createClient } from "@/lib/supabase/client";
import { formatAuthNetworkError } from "@/lib/supabase/env";
import { formatAuthError, formatSignupError } from "@/lib/supabase/auth-errors";
import { ensureUserProfile } from "@/lib/auth/resolve-portal-role";
import type { PortalRole } from "@/lib/auth/roles";
import { loginPathForRole, PORTAL_ROUTES } from "@/lib/auth/roles";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { PasswordInput } from "@/components/ui/password-input";
import { Label } from "@/components/ui/label";
import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";

async function signupViaApi(
  email: string,
  password: string,
  displayName: string,
  portalRole: PortalRole
) {
  const res = await fetch("/api/auth/signup", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ email, password, displayName, portalRole }),
  });
  const json = (await res.json()) as {
    success: boolean;
    error?: string;
    useClient?: boolean;
    needsEmailConfirmation?: boolean;
  };
  return { ok: res.ok && json.success, status: res.status, ...json };
}

export function SignupForm({
  portalRole,
  title,
  description,
}: {
  portalRole: PortalRole;
  title: string;
  description: string;
}) {
  const router = useRouter();
  const [email, setEmail] = useState("");
  const [password, setPassword] = useState("");
  const [displayName, setDisplayName] = useState("");
  const [error, setError] = useState<string | null>(null);
  const [loading, setLoading] = useState(false);

  const loginHref = loginPathForRole(portalRole);
  const portalLabel =
    portalRole === "league_master" ? "League Master" : "Team Manager";

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    setLoading(true);
    setError(null);

    try {
      const trimmedEmail = email.trim();
      const api = await signupViaApi(
        trimmedEmail,
        password,
        displayName,
        portalRole
      );

      if (api.ok) {
        if (api.needsEmailConfirmation) {
          setError(
            `Confirm your email, then sign in at ${portalLabel} login.`
          );
          return;
        }

        const supabase = createClient();
        const { error: signInError } = await supabase.auth.signInWithPassword({
          email: trimmedEmail,
          password,
        });
        if (signInError) {
          setError(
            `Account created. Sign in at ${loginHref} (${signInError.message})`
          );
          return;
        }
        router.push(PORTAL_ROUTES[portalRole]);
        router.refresh();
        return;
      }

      if (api.status !== 503 && !api.useClient) {
        setError(formatSignupError(api.error ?? "Signup failed"));
        return;
      }

      const supabase = createClient();
      const { data, error: authError } = await supabase.auth.signUp({
        email: trimmedEmail,
        password,
        options: {
          data: { display_name: displayName, portal_role: portalRole },
        },
      });

      if (authError) {
        setError(formatAuthError(authError));
        return;
      }

      if (data.user && !data.session) {
        setError(
          `Confirm your email, then sign in at ${portalLabel} login.`
        );
        return;
      }

      if (data.user) {
        const sync = await ensureUserProfile(
          supabase,
          data.user,
          portalRole,
          displayName
        );
        if (sync.error === "schema") {
          setError(
            "Account created but database needs an update. Run: npm run db:push — then sign in."
          );
          return;
        }
        if (!sync.ok && sync.error) {
          setError(formatSignupError(sync.error));
          return;
        }
      }

      router.push(PORTAL_ROUTES[portalRole]);
      router.refresh();
    } catch (err) {
      setError(formatAuthNetworkError(err));
    } finally {
      setLoading(false);
    }
  }

  return (
    <div className="retro-grid flex min-h-screen items-center justify-center px-4 py-12">
      <Card className="retro-card w-full max-w-md border-border/80">
        <CardHeader>
          <p className="font-display text-[10px] font-bold uppercase tracking-[0.2em] text-neon">
            Yaltopia FIFA
          </p>
          <CardTitle className="font-display text-xl font-black uppercase tracking-wide">
            {title}
          </CardTitle>
          <CardDescription>{description}</CardDescription>
        </CardHeader>
        <CardContent>
          <form onSubmit={handleSubmit} className="space-y-4">
            <div className="space-y-2">
              <Label>Display name</Label>
              <Input
                value={displayName}
                onChange={(e) => setDisplayName(e.target.value)}
              />
            </div>
            <div className="space-y-2">
              <Label>Email</Label>
              <Input
                type="email"
                value={email}
                onChange={(e) => setEmail(e.target.value)}
                required
                autoComplete="email"
              />
            </div>
            <div className="space-y-2">
              <Label>Password</Label>
              <PasswordInput
                value={password}
                onChange={(e) => setPassword(e.target.value)}
                required
                minLength={6}
                autoComplete="new-password"
              />
            </div>
            {error && (
              <p className="whitespace-pre-line text-sm text-red-400">{error}</p>
            )}
            <Button type="submit" variant="neon" className="w-full" disabled={loading}>
              {loading ? "Creating account…" : "Create account"}
            </Button>
          </form>
          <p className="mt-4 text-center text-sm text-muted-foreground">
            <Link href={loginHref} className="text-neon hover:underline">
              Sign in
            </Link>
            {portalRole === "manager" && (
              <>
                {" · "}
                <Link href="/" className="hover:underline">
                  Home
                </Link>
              </>
            )}
          </p>
        </CardContent>
      </Card>
    </div>
  );
}