"use client";

import { useEffect, useState } from "react";
import { Check } from "lucide-react";

import { InlineSpinner } from "@/components/inline-spinner";
import { activityCompletedSteps, activityElapsedLabel } from "@/lib/chat-message-view";

export type AgentActivityState = "working" | "searching" | "solving" | "listening" | "composing" | "shaping";

const labels = {
  working: "正在处理任务…",
  searching: "正在搜索相关信息…",
  solving: "正在分析问题…",
  listening: "正在聆听…",
  composing: "正在组织回答…",
  shaping: "正在生成结果…",
} as const satisfies Record<AgentActivityState, string>;

function ActivityElapsed({ startedAt }: Readonly<{ startedAt: number }>) {
  const [now, setNow] = useState(() => Date.now());
  useEffect(() => {
    const timer = window.setInterval(() => setNow(Date.now()), 1000);
    return () => window.clearInterval(timer);
  }, []);
  const label = activityElapsedLabel(startedAt, now);
  if (!label) return null;
  return <span className="agent-activity-status__elapsed" aria-hidden="true">{label}</span>;
}

function MessageThinkingTrace({
  text,
  hasAnswer,
}: Readonly<{
  text: string;
  hasAnswer: boolean;
}>) {
  const [userOpen, setUserOpen] = useState<boolean | null>(null);
  const open = userOpen ?? !hasAnswer;
  if (!text.trim()) return null;
  return (
    <details
      className="message-thinking"
      open={open}
      onToggle={(event) => {
        setUserOpen((event.currentTarget as HTMLDetailsElement).open);
      }}
    >
      <summary>思考</summary>
      <div className="message-thinking-body">{text}</div>
    </details>
  );
}

function VargaTraceStep({ sentence }: Readonly<{ sentence: string }>) {
  return (
    <li className="agent-thinking-step is-done">
      <span className="agent-thinking-marker" aria-hidden="true">
        <Check />
      </span>
      <span>{sentence}</span>
    </li>
  );
}

/**
 * Fallback activity panel for an assistant row that carries no step timeline.
 * Both chat surfaces normally render `ConsultationRunTimeline`; this remains
 * for rows that only have a phase label, a completed trail or thinking text.
 * The live marker is the shared `InlineSpinner`, the same one the timeline uses.
 */
export function AgentActivityStatus({
  state,
  label = labels[state],
  startedAt,
  completedTrail,
  thinkingText,
  vargaSentence,
  hasAnswer = false,
  showLive = true,
}: Readonly<{
  state: AgentActivityState;
  label?: string;
  startedAt?: number;
  completedTrail?: string;
  thinkingText?: string;
  vargaSentence?: string | null;
  hasAnswer?: boolean;
  showLive?: boolean;
}>) {
  const completedSteps = activityCompletedSteps(completedTrail);
  const live = showLive && !hasAnswer;
  const varga = vargaSentence?.trim() ?? "";
  const showVarga = Boolean(varga);
  if (!live && completedSteps.length === 0 && !thinkingText?.trim() && !showVarga) return null;

  return (
    <div className="agent-thinking-panel agent-activity-status">
      {(live || completedSteps.length > 0 || showVarga) && (
        <ol className="agent-thinking-timeline">
          {completedSteps.map((step) => (
            <li className="agent-thinking-step is-done" key={step}>
              <span className="agent-thinking-marker" aria-hidden="true">
                <Check />
              </span>
              <span>{step}</span>
            </li>
          ))}
          {live ? (
            <li className="agent-thinking-step is-live">
              <span className="agent-thinking-marker is-live-marker" aria-hidden="true">
                <InlineSpinner size={12} />
              </span>
              <span className="agent-activity-status__live" role="status">
                <span key={label} className="agent-activity-status__text">{label}</span>
                {startedAt ? <ActivityElapsed key={startedAt} startedAt={startedAt} /> : null}
              </span>
            </li>
          ) : null}
          {showVarga ? <VargaTraceStep sentence={varga} /> : null}
        </ol>
      )}
      {thinkingText ? <MessageThinkingTrace text={thinkingText} hasAnswer={hasAnswer} /> : null}
    </div>
  );
}