import { RefreshCw } from "lucide-react";
import { useEffect, useState } from "react";
import { DropdownMenuItem } from "@tutti-os/ui-system";

import { toLocalShortDateTime } from "../../app/renderer/shell/utils/format";

export interface AgentProbeUsageFreshnessLabels {
  justUpdated: string;
  minutesAgo: (count: number) => string;
  hoursAgo: (count: number) => string;
  updating: string;
  refreshFailed: string;
  refreshAria: string;
}

/** How often the relative "updated N ago" label re-renders while the popover
 * is open. Coarse on purpose — minute-level granularity doesn't need a faster
 * tick, and the popover only mounts (so this interval only runs) while open. */
const FRESHNESS_TICK_MS = 20_000;

function freshnessAgeText(
  capturedAtUnixMs: number,
  nowMs: number,
  labels: AgentProbeUsageFreshnessLabels
): string {
  const ageMs = Math.max(0, nowMs - capturedAtUnixMs);
  const minutes = Math.floor(ageMs / 60_000);
  if (minutes < 1) {
    return labels.justUpdated;
  }
  if (minutes < 60) {
    return labels.minutesAgo(minutes);
  }
  const hours = Math.floor(minutes / 60);
  if (hours < 24) {
    return labels.hoursAgo(hours);
  }
  return toLocalShortDateTime(capturedAtUnixMs);
}

/**
 * Header-right control for a usage/limits popover: a single clickable affordance
 * that both surfaces data freshness ("Updated 3m ago" / "Updating…" / "Refresh
 * failed") and, on click, forces a fresh probe fetch. Keeping freshness and the
 * refresh action in one control makes the cause/effect obvious — the timestamp
 * is what the button updates.
 */
export function AgentProbeUsageFreshness({
  ariaDescribedBy,
  capturedAtUnixMs,
  isLoading,
  didFail,
  onRefresh,
  labels,
  disabled = false,
  presentation = "button",
  testId
}: {
  ariaDescribedBy?: string;
  capturedAtUnixMs: number | null;
  isLoading: boolean;
  didFail: boolean;
  onRefresh: () => void;
  labels: AgentProbeUsageFreshnessLabels;
  disabled?: boolean;
  presentation?: "button" | "menu-item";
  testId?: string;
}): React.JSX.Element {
  const [nowMs, setNowMs] = useState(() => Date.now());
  // Bumped on every click. A refresh can be a no-op (served from the
  // main-process throttle cache within its TTL) and never flip `isLoading`, so
  // the click would otherwise produce no motion at all. Replaying a one-shot
  // spin keyed on this nonce gives a reassuring acknowledgement regardless.
  const [clickSpinNonce, setClickSpinNonce] = useState(0);
  const showRelativeTime =
    !isLoading && !didFail && typeof capturedAtUnixMs === "number";

  const handleClick = (): void => {
    setClickSpinNonce((nonce) => nonce + 1);
    onRefresh();
  };

  useEffect(() => {
    if (!showRelativeTime) {
      return;
    }
    setNowMs(Date.now());
    const timer = setInterval(() => setNowMs(Date.now()), FRESHNESS_TICK_MS);
    return () => clearInterval(timer);
  }, [showRelativeTime, capturedAtUnixMs]);

  const text = isLoading
    ? labels.updating
    : didFail
      ? labels.refreshFailed
      : typeof capturedAtUnixMs === "number"
        ? freshnessAgeText(capturedAtUnixMs, nowMs, labels)
        : "";

  const stateClassName = didFail
    ? "text-[var(--state-danger)] hover:text-[var(--state-danger)]"
    : "text-[var(--text-tertiary)] hover:text-[var(--text-primary)]";

  const content = (
    <>
      <RefreshCw
        // Remount on each click (and when loading toggles) so the CSS animation
        // restarts: a continuous spin while a fetch is in flight, otherwise a
        // single reassuring turn per click.
        key={isLoading ? "loading" : `spin-${clickSpinNonce}`}
        size={12}
        strokeWidth={2}
        aria-hidden="true"
        className={
          isLoading
            ? "animate-spin"
            : clickSpinNonce > 0
              ? "motion-safe:animate-[spin_0.6s_linear]"
              : undefined
        }
      />
      {text ? <span className="whitespace-nowrap">{text}</span> : null}
    </>
  );

  if (presentation === "menu-item") {
    return (
      <DropdownMenuItem
        aria-busy={isLoading}
        aria-describedby={ariaDescribedBy}
        aria-label={labels.refreshAria}
        className={`h-6 shrink-0 gap-1 px-1 text-[11px] ${stateClassName}`}
        data-state={isLoading ? "loading" : didFail ? "failed" : "idle"}
        data-testid={testId}
        disabled={isLoading || disabled}
        onSelect={(event) => {
          event.preventDefault();
          handleClick();
        }}
        title={labels.refreshAria}
      >
        {content}
      </DropdownMenuItem>
    );
  }

  return (
    <button
      type="button"
      aria-describedby={ariaDescribedBy}
      data-testid={testId}
      data-state={isLoading ? "loading" : didFail ? "failed" : "idle"}
      className={`nodrag inline-flex shrink-0 cursor-pointer items-center gap-1 rounded-[5px] px-1 py-0.5 text-[11px] leading-4 transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-[var(--border-focus)] disabled:cursor-default disabled:opacity-70 [-webkit-app-region:no-drag] ${stateClassName}`}
      onClick={handleClick}
      disabled={isLoading || disabled}
      aria-label={labels.refreshAria}
      aria-busy={isLoading}
      title={labels.refreshAria}
    >
      {content}
    </button>
  );
}