import { useState } from "react";
import { useMutation } from "@tanstack/react-query";
import { createFileRoute, useNavigate } from "@tanstack/react-router";
import { ShieldCheck, KeyRound, AlertTriangle } from "lucide-react";

import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { Badge } from "@/components/ui/badge";
import { api, unwrap, ApiError } from "@/lib/api";

export const Route = createFileRoute("/login")({
  component: LoginPage,
});

function LoginPage() {
  const navigate = useNavigate();
  const [devSubject, setDevSubject] = useState("CN=lab.operator,OU=PKI,O=SMGW");
  const [err, setErr] = useState<string | null>(null);

  const login = useMutation({
    mutationFn: () =>
      unwrap(
        api.POST("/auth/session", {
          body: { dev_subject: devSubject },
        }),
      ),
    onError: (e: ApiError) => setErr(e.message),
    onSuccess: () => navigate({ to: "/" }),
  });

  return (
    <div className="min-h-screen grid lg:grid-cols-[1.05fr_0.95fr]">
      <aside className="relative hidden lg:flex flex-col justify-between p-12 border-r border-line overflow-hidden bg-paper">
        <div className="absolute inset-0 grid-bg opacity-60 pointer-events-none" />
        <div className="relative z-10 flex items-center gap-3">
          <div className="size-10 rounded-[12px] bg-ink text-paper grid place-items-center font-display font-semibold text-[17px] tracking-[-0.02em]">
            sm
          </div>
          <div className="leading-tight">
            <div className="font-display text-[16px] font-semibold tracking-[-0.015em] text-ink">
              SMGW PKI · Console
            </div>
            <div className="text-[11px] uppercase tracking-[0.1em] text-ink-faint">
              Test / Labor — BSI TR-03129-4
            </div>
          </div>
        </div>

        <div className="relative z-10 max-w-md space-y-6">
          <p className="font-serif italic text-[34px] leading-[1.1] text-ink tracking-[-0.01em]">
            Eine ruhige Konsole für eine{" "}
            <span className="not-italic font-display font-semibold">
              vorsichtige PKI
            </span>
            .
          </p>
          <p className="text-[13.5px] leading-relaxed text-ink-mute">
            Steuerfläche für den smgw-pki-automator. Erneuerungen, Sub-CA-Status,
            iconfig-Generierung und SoftHSM-Diagnose — alle Operationen sind
            auditiert und an mTLS-Identitäten gebunden.
          </p>
          <div className="flex flex-wrap gap-2">
            <Badge tone="outline">TR-03129-4</Badge>
            <Badge tone="outline">TR-03109-1</Badge>
            <Badge tone="outline">SM-PKI CP</Badge>
          </div>
        </div>

        <div className="relative z-10 text-[11.5px] text-ink-faint mono">
          v0.1.0 · build skeleton · {new Date().getFullYear()}
        </div>
      </aside>

      <section className="flex items-center justify-center p-8">
        <div className="w-full max-w-[420px] surface p-7">
          <div className="flex items-center gap-2 text-[11px] uppercase tracking-[0.1em] text-ink-faint">
            <ShieldCheck className="size-3.5 text-accent" />
            Sitzung
          </div>
          <h2 className="mt-3 font-display text-[26px] font-semibold tracking-[-0.02em] text-ink">
            Anmeldung über mTLS
          </h2>
          <p className="mt-1.5 text-[13px] leading-relaxed text-ink-mute">
            Ihr Client-Zertifikat wird vom Reverse Proxy terminiert und im Header{" "}
            <code className="mono text-[12px]">X-Forwarded-Cert-Subject</code>{" "}
            übergeben. Im Lab-Modus ist ein Dev-Subject als Fallback erlaubt.
          </p>

          <form
            onSubmit={(e) => {
              e.preventDefault();
              setErr(null);
              login.mutate();
            }}
            className="mt-7 space-y-4"
          >
            <div className="space-y-1.5">
              <Label htmlFor="dev_subject">Dev-Subject (nur Lab)</Label>
              <Input
                id="dev_subject"
                value={devSubject}
                onChange={(e) => setDevSubject(e.target.value)}
                mono
                placeholder="CN=…"
              />
              <p className="text-[11.5px] text-ink-faint">
                Wird ignoriert, sobald der Proxy ein gültiges Cert-Subject mitschickt.
              </p>
            </div>

            {err && (
              <div className="flex gap-2 items-start surface-inset p-3 text-[12.5px] text-danger">
                <AlertTriangle className="size-4 mt-0.5 shrink-0" />
                <span>{err}</span>
              </div>
            )}

            <Button
              type="submit"
              variant="primary"
              size="lg"
              className="w-full"
              disabled={login.isPending}
            >
              <KeyRound className="size-4" />
              Sitzung erstellen
            </Button>
          </form>

          <div className="mt-6 pt-5 border-t border-line text-[11.5px] text-ink-faint leading-relaxed">
            Cookies sind <span className="text-ink">HttpOnly</span> und{" "}
            <span className="text-ink">SameSite=Strict</span>. Sitzungsdauer 8 h.
          </div>
        </div>
      </section>
    </div>
  );
}