/**
 * 工作台后四要素的共用小件 —— 自 `~/coding/JCAI_PRD/workbench/_components/ModuleWorkspace.tsx`
 * 第 21–160 行平移。**DOM 与 `jc-*` 类名原样保留**(README 平移规则 1/2/4)。
 *
 * 四要素同款三栏布局:左清单 `task-sidebar` / 中文档卡 `execution-panel` / 右会话 `session-chat`。
 */
import type { ReactNode } from 'react';
import { Ico } from '@web-shared/Ico.tsx';
import ScrollArea from '@web-shared/ScrollArea.tsx';

/** 首字头像:名字 hash 取渐变色;外文名取首字母大写 */
const AVA_GRAD: ReadonlyArray<readonly [string, string]> = [
  ['#2bc7d4', '#0e9fd8'],
  ['#3370ff', '#245bdb'],
  ['#7f3bf5', '#5b21cf'],
  ['#ff8800', '#de7802'],
  ['#0aa294', '#0a6a64'],
  ['#f14ba9', '#c92d86'],
];

function avaOf(name: string): { ch: string; grad: readonly [string, string] } {
  let h = 0;
  for (const c of name) h = (h * 31 + c.charCodeAt(0)) >>> 0;
  const first = name[0] ?? '·';
  const ch = /[A-Za-z]/.test(first) ? first.toUpperCase() : first;
  return { ch, grad: AVA_GRAD[h % AVA_GRAD.length]! };
}

export function Avatar({ name, size = 30 }: { name: string; size?: number }) {
  const { ch, grad } = avaOf(name);
  return (
    <span
      className="jc-ava"
      style={{
        width: size,
        height: size,
        fontSize: size * 0.42,
        background: `linear-gradient(140deg, ${grad[0]}, ${grad[1]})`,
      }}
    >
      {ch}
    </span>
  );
}

export function AvatarStack({ names, size = 26 }: { names: readonly string[]; size?: number }) {
  const show = names.slice(0, 5);
  return (
    <span className="jc-ava-stack">
      {show.map((n, i) => (
        <span key={i} className="jc-ava-slot">
          <Avatar name={n} size={size} />
        </span>
      ))}
      {names.length > show.length && <span className="jc-ava-slot jc-ava-more">+{names.length - show.length}</span>}
    </span>
  );
}

export type Tone = 'todo' | 'doing' | 'done' | 'warn' | 'brand' | 'ok';

export function Chip({ tone, label, pulse }: { tone: Tone; label: string; pulse?: boolean }) {
  return (
    <span className={'jc-chip t-' + tone}>
      {pulse && <i />}
      {label}
    </span>
  );
}

/** 文档头(渐变图标块 + 标题 + 元信息 + 右上状态章)—— 统一容器,彻底告别贴边 */
export function Hero({
  grad,
  icon,
  kicker,
  title,
  meta,
  chip,
}: {
  grad: readonly [string, string];
  icon: string;
  kicker?: string;
  title: string;
  meta: ReactNode;
  chip?: ReactNode;
}) {
  return (
    <header className="jc-hero">
      <span className="jc-hero-ico" style={{ background: `linear-gradient(140deg, ${grad[0]}, ${grad[1]})` }}>
        <Ico name={icon} s={22} />
      </span>
      <div className="jc-hero-txt">
        {kicker && <span className="jc-hero-kicker">{kicker}</span>}
        <h2>{title}</h2>
        <div className="jc-hero-meta">{meta}</div>
      </div>
      {chip && <div className="jc-hero-chip">{chip}</div>}
    </header>
  );
}

export function Section({
  icon,
  title,
  extra,
  children,
}: {
  icon: string;
  title: string;
  extra?: ReactNode;
  children: ReactNode;
}) {
  return (
    <section className="jc-sec">
      <div className="jc-sec-head">
        <Ico name={icon} s={13} />
        <span>{title}</span>
        {extra && <span className="jc-sec-extra">{extra}</span>}
      </div>
      {children}
    </section>
  );
}

/** 侧栏表头 —— 四要素共用 */
export function SidebarHead({ icon, title, sub }: { icon: string; title: string; sub: string }) {
  return (
    <div className="sidebar-head jc-wl-head">
      <span className="jc-wl-ico">
        <Ico name={icon} s={16} />
      </span>
      <div>
        <h2>{title}</h2>
        <span>{sub}</span>
      </div>
    </div>
  );
}

/**
 * 列表区空态 —— 侧栏窄,用紧凑版:软色圆里一枚图标 + 主句 + 一小段说明。
 * 与主面板的 `EmptyState`(整屏光环)同一语气,尺寸各归其位。
 */
export function ListEmpty({
  icon,
  title,
  children,
}: {
  icon: string;
  title?: string;
  children: ReactNode;
}) {
  return (
    <div className="jc-side-empty">
      <span className="jc-side-empty-ico">
        <Ico name={icon} s={18} />
      </span>
      {title !== undefined && <b>{title}</b>}
      <p>{children}</p>
    </div>
  );
}

/** 中栏文档卡的滚动容器 */
export function DocPanel({ scrollKey, children }: { scrollKey: string; children: ReactNode }) {
  return (
    <main className="execution-panel jc-panel-card">
      <ScrollArea key={scrollKey} className="jc-sa--full" vpClassName="jc-mod-scroll">
        {children}
      </ScrollArea>
    </main>
  );
}

/**
 * 说明带 —— 原型里用来点明规范口径的那条浅色横条。
 * 保留它不是为了好看:这些句子是「为什么这么设计」的现场注解。
 */
export function NoteBand({ children }: { children: ReactNode }) {
  return (
    <div className="jc-notrig">
      <Ico name="info" s={15} />
      <span>{children}</span>
    </div>
  );
}

/**
 * 空态整屏 —— 层叠光环 + 图标 + 主副文 + 提示囊(自原型 `EmptyState` 平移)。
 *
 * **空态是产品的常态,不是缺陷**:文案一律从用人的角度写「你手上现在没有什么」,
 * 而不是从开发角度写「这块还没做」—— 后者是给自己看的,前者才是用户要的那句话。
 *
 * 三个色调分的是**三种空**,不是三种好看:
 * - `ok`    办完了、清空了 —— 这是好事(待批清空、无未读)
 * - `brand` 还没发生,但通路是通的 —— 等着就会有(还没有任务、还没有成果)
 * - `muted` 通路还没接 —— 等下去也不会有内容。灰着,别让人白等
 */
export function EmptyState({
  ico,
  tone,
  title,
  desc,
  hint,
}: {
  ico: string;
  tone: 'ok' | 'brand' | 'muted';
  title: string;
  desc: string;
  hint?: string | undefined;
}) {
  return (
    <div className={'jc-empty t-' + tone}>
      <span className="jc-empty-art">
        <i className="r1" />
        <i className="r2" />
        <span className="jc-empty-ico">
          <Ico name={ico} s={26} />
        </span>
      </span>
      <b>{title}</b>
      <p>{desc}</p>
      {hint !== undefined && (
        <span className="jc-empty-hint">
          <Ico name="sparkles" s={12} />
          {hint}
        </span>
      )}
    </div>
  );
}