import { SegmentQualifier } from "@/components/auth/segment-qualifier";
import { useAuth } from "@/hooks/use-auth";
import { capture, setPeopleProperties } from "@/lib/posthog";
import { Button } from "@sase/ui";
import { useLocation } from "@tanstack/react-router";
import { useEffect, useState } from "react";

/**
 * Universal post-auth segment gate.
 *
 * The register page gates segment selection behind the form, but that only
 * covers email + register-page-OAuth signups. A user who starts Google OAuth
 * from the LOGIN page (login.tsx) gets an account created server-side and lands
 * on the dashboard with no segment ever chosen — this is the bulk of the ~41%
 * of signups with a null segment. Segment isn't persisted server-side (only
 * localStorage + a PostHog person property), so we enforce it here at the one
 * chokepoint every authenticated user passes through: the dashboard.
 *
 * Behaviour (product decision 2026-07-27):
 *  - New users (account created in the last few minutes → the login-OAuth gap):
 *    MANDATORY, non-dismissible modal.
 *  - Existing segment-less users (the ~538 backfill): SOFT, dismissible with a
 *    cooldown so we re-ask later without nagging or blocking active/paying users.
 *
 * This is a baseline fix shipped to everyone — NOT the `funnel-bucket` A/B
 * experiment (that gates the tailored value/upgrade experience separately).
 */
const SEGMENT_KEY = "sase-b2b-segment";
const DISMISS_UNTIL_KEY = "sase-b2b-segment-prompt-until";
// Account younger than this ⇒ treat as a fresh signup (mandatory). Generous so
// the signup → first dashboard load always counts, even with a slow OAuth hop.
const NEW_USER_WINDOW_MS = 15 * 60 * 1000;
// How long a "Daha sonra" dismissal silences the soft prompt for existing users.
const DISMISS_COOLDOWN_MS = 7 * 24 * 60 * 60 * 1000;

function readSegment(): string | null {
  try {
    return localStorage.getItem(SEGMENT_KEY);
  } catch {
    return null;
  }
}

export function SegmentGate() {
  const { user, isLoading } = useAuth();
  const location = useLocation();
  const [open, setOpen] = useState(false);
  const [mandatory, setMandatory] = useState(false);

  useEffect(() => {
    // Only inside the app, only once the session has resolved to a real user.
    if (isLoading || !user) {
      setOpen(false);
      return;
    }
    if (!location.pathname.startsWith("/dashboard")) {
      setOpen(false);
      return;
    }
    // Already segmented — nothing to do. (Register writes this pre-redirect, so
    // email + register-OAuth signups never see the gate.)
    if (readSegment()) {
      setOpen(false);
      return;
    }

    const createdAt = user.createdAt ? new Date(user.createdAt).getTime() : 0;
    const isNew = createdAt > 0 && Date.now() - createdAt < NEW_USER_WINDOW_MS;

    if (isNew) {
      setMandatory(true);
      setOpen(true);
      return;
    }

    // Existing segment-less user: honour the soft-dismiss cooldown.
    let dismissedUntil = 0;
    try {
      dismissedUntil = Number(localStorage.getItem(DISMISS_UNTIL_KEY)) || 0;
    } catch {
      dismissedUntil = 0;
    }
    if (Date.now() < dismissedUntil) {
      setOpen(false);
      return;
    }
    setMandatory(false);
    setOpen(true);
  }, [user, isLoading, location.pathname]);

  if (!open) return null;

  function handleSelect(seg: string) {
    try {
      localStorage.setItem(SEGMENT_KEY, seg);
    } catch {
      // localStorage unavailable — still fire analytics below.
    }
    // `source` distinguishes the login-OAuth gap fill from the backfill so we can
    // measure each in PostHog; mirrors register.tsx's signup_segment_selected.
    capture("signup_segment_selected", {
      segment: seg,
      source: mandatory ? "post_signup_gate" : "backfill_gate",
    });
    setPeopleProperties({ b2b_segment: seg });
    setOpen(false);
  }

  function handleDismiss() {
    try {
      localStorage.setItem(DISMISS_UNTIL_KEY, String(Date.now() + DISMISS_COOLDOWN_MS));
    } catch {
      // best-effort
    }
    capture("signup_segment_prompt_dismissed");
    setOpen(false);
  }

  return (
    <div
      className="fixed inset-0 z-[60] flex items-center justify-center overflow-y-auto bg-background/80 p-4 backdrop-blur-sm"
      // biome-ignore lint/a11y/useSemanticElements: overlay modal — role="dialog"+aria-modal is the correct ARIA here; a native <dialog> would need imperative showModal() plumbing this SPA overlay doesn't use
      role="dialog"
      aria-modal="true"
      aria-label="İşletme türü seçimi"
    >
      <div className="my-auto w-full max-w-md rounded-2xl border border-border bg-card p-6 shadow-xl">
        <div>
          <h2 className="text-xl font-bold tracking-tight">Bu platform kimler için?</h2>
          <p className="mt-2 text-sm text-muted-foreground">
            İşletmeni seç — sana uygun sınırsız şase sorgulama erişimini açalım.
          </p>
        </div>
        <div className="mt-5">
          <SegmentQualifier onSelect={handleSelect} />
        </div>
        {!mandatory && (
          <Button variant="ghost" className="mt-3 w-full" onClick={handleDismiss}>
            Daha sonra
          </Button>
        )}
      </div>
    </div>
  );
}