import { createFileRoute, Link, useNavigate } from "@tanstack/react-router";
import { useEffect, useState } from "react";
import { useServerFn } from "@tanstack/react-start";
import { Camera } from "lucide-react";
import { supabase } from "@/integrations/supabase/client";
import { lovable } from "@/integrations/lovable";
import { trackEvent } from "@/lib/analytics.functions";
import { toast } from "sonner";

export const Route = createFileRoute("/auth")({
  head: () => ({
    meta: [
      { title: "Sign in — Personal Photoshoot Studio™" },
      { name: "description", content: "Sign in to save and manage your photoshoot plans." },
    ],
  }),
  component: AuthPage,
});

function AuthPage() {
  const navigate = useNavigate();
  const track = useServerFn(trackEvent);
  const [mode, setMode] = useState<"signin" | "signup">("signin");
  const [email, setEmail] = useState("");
  const [password, setPassword] = useState("");
  const [name, setName] = useState("");
  const [busy, setBusy] = useState(false);
  const [confirmRequired, setConfirmRequired] = useState(false);

  useEffect(() => {
    supabase.auth.getSession().then(({ data }) => {
      if (data.session) navigate({ to: "/library" });
    });
  }, [navigate]);

  async function handleEmail(e: React.FormEvent) {
    e.preventDefault();
    setBusy(true);
    setConfirmRequired(false);
    try {
      if (mode === "signup") {
        const { data, error } = await supabase.auth.signUp({
          email,
          password,
          options: {
            emailRedirectTo: `${window.location.origin}/library`,
            data: { full_name: name || email.split("@")[0] },
          },
        });
        if (error) throw error;
        void track({ data: { event: "signup", props: { method: "email" } } }).catch(() => {});
        if (!data.session) {
          setConfirmRequired(true);
          toast.success("Account created. Check your email to confirm your account.");
          return;
        }
        toast.success("Account created. You're signed in.");
      } else {
        const { error } = await supabase.auth.signInWithPassword({ email, password });
        if (error) throw error;
        void track({ data: { event: "login", props: { method: "email" } } }).catch(() => {});
      }
      navigate({ to: "/library" });
    } catch (err) {
      toast.error(err instanceof Error ? err.message : "Authentication failed");
    } finally {
      setBusy(false);
    }
  }

  async function handleGoogle() {
    setBusy(true);
    try {
      const result = await lovable.auth.signInWithOAuth("google", {
        redirect_uri: window.location.origin + "/library",
      });
      if (result.error) {
        toast.error(result.error.message ?? "Google sign-in failed");
        return;
      }
      if (result.redirected) return;
      navigate({ to: "/library" });
    } finally {
      setBusy(false);
    }
  }

  return (
    <div className="min-h-screen bg-background flex items-center justify-center px-6">
      <div className="w-full max-w-md">
        <Link to="/" className="flex items-center justify-center gap-2 mb-10">
          <div className="h-9 w-9 rounded-full bg-gradient-gold flex items-center justify-center">
            <Camera className="h-4 w-4 text-primary" />
          </div>
          <span className="font-display text-xl font-semibold">
            Personal Photoshoot Studio<span className="text-gold">™</span>
          </span>
        </Link>

        <div className="rounded-2xl border border-border bg-card p-8 shadow-soft">
          <p className="text-xs uppercase tracking-[0.3em] text-gold mb-2 text-center">
            {mode === "signin" ? "Welcome back" : "Create account"}
          </p>
          <h1 className="font-display text-3xl text-center mb-8 leading-tight">
            {mode === "signin" ? "Sign in to your studio" : "Begin your story"}
          </h1>

          <button
            type="button"
            onClick={handleGoogle}
            disabled={busy}
            className="w-full inline-flex items-center justify-center gap-3 rounded-full border border-border bg-background px-4 py-2.5 text-sm font-medium hover:bg-accent transition disabled:opacity-50"
          >
            <GoogleIcon /> Continue with Google
          </button>

          <div className="my-6 flex items-center gap-3 text-xs uppercase tracking-[0.25em] text-muted-foreground">
            <div className="h-px bg-border flex-1" /> or <div className="h-px bg-border flex-1" />
          </div>

          <form onSubmit={handleEmail} className="space-y-4">
            {mode === "signup" && (
              <Field label="Name">
                <input
                  type="text"
                  value={name}
                  onChange={(e) => setName(e.target.value)}
                  className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-ring"
                  placeholder="Your name"
                />
              </Field>
            )}
            <Field label="Email">
              <input
                type="email"
                required
                value={email}
                onChange={(e) => setEmail(e.target.value)}
                className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-ring"
                placeholder="you@studio.com"
              />
            </Field>
            <Field label="Password">
              <input
                type="password"
                required
                minLength={6}
                value={password}
                onChange={(e) => setPassword(e.target.value)}
                className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-ring"
                placeholder="••••••••"
              />
            </Field>
            <button
              type="submit"
              disabled={busy}
              className="w-full rounded-full bg-primary text-primary-foreground py-2.5 text-sm font-medium hover:opacity-90 transition disabled:opacity-50"
            >
              {busy ? "Please wait…" : mode === "signin" ? "Sign in" : "Create account"}
            </button>
          </form>

          {confirmRequired && (
            <div className="mt-5 rounded-xl border border-gold/30 bg-gold/10 p-4 text-sm text-foreground">
              <p className="font-medium">Confirm your email</p>
              <p className="mt-1 text-muted-foreground">
                We sent a confirmation link to <span className="text-foreground">{email}</span>. Click the link to sign in.
              </p>
            </div>
          )}

          <p className="text-center text-sm text-muted-foreground mt-6">
            {mode === "signin" ? "New here?" : "Already have an account?"}{" "}
            <button
              type="button"
              onClick={() => setMode(mode === "signin" ? "signup" : "signin")}
              className="text-foreground underline underline-offset-4 decoration-gold decoration-2 font-medium"
            >
              {mode === "signin" ? "Create an account" : "Sign in"}
            </button>
          </p>
        </div>
      </div>
    </div>
  );
}

function Field({ label, children }: { label: string; children: React.ReactNode }) {
  return (
    <label className="block">
      <span className="text-[10px] uppercase tracking-[0.25em] text-muted-foreground block mb-1.5">
        {label}
      </span>
      {children}
    </label>
  );
}

function GoogleIcon() {
  return (
    <svg viewBox="0 0 24 24" className="h-4 w-4">
      <path
        fill="#4285F4"
        d="M22.56 12.25c0-.78-.07-1.53-.2-2.25H12v4.26h5.92c-.26 1.37-1.04 2.53-2.21 3.31v2.75h3.57c2.08-1.92 3.28-4.74 3.28-8.07z"
      />
      <path
        fill="#34A853"
        d="M12 23c2.97 0 5.46-.98 7.28-2.66l-3.57-2.75c-.99.66-2.25 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"
      />
      <path
        fill="#FBBC05"
        d="M5.84 14.12c-.22-.66-.35-1.36-.35-2.12s.13-1.46.35-2.12V7.04H2.18C1.43 8.55 1 10.22 1 12s.43 3.45 1.18 4.96l3.66-2.84z"
      />
      <path
        fill="#EA4335"
        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 7.04l3.66 2.84C6.71 7.31 9.14 5.38 12 5.38z"
      />
    </svg>
  );
}