import type { ReactNode } from "react";
import { Link, NavLink } from "react-router-dom";

import { ru } from "../content/ru";
import { useDialog } from "../dialog/DialogContext";
import { useSession } from "../session/SessionContext";
import { HotlineCard, useHelp } from "./HelpSheet";
import { Icon, LogoMark, type IconName } from "./Icon";

/*
 * Shared patient workspace, following the approved doctor dashboard.
 *  phone:   content → «Экстренная помощь» block → bottom tab bar (signed in)
 *  desktop: white sidebar | workspace header | content + emergency panel
 *  bare:    one centred column on every width (questionnaires)
 */

const TABS: { to: string; label: string; icon: IconName }[] = [
  { to: "/today", label: ru.nav.today, icon: "home" },
  { to: "/messages", label: ru.nav.chat, icon: "message" },
  { to: "/meds", label: ru.nav.meds, icon: "pill" },
  { to: "/doctor", label: ru.nav.doctor, icon: "doctor" },
  { to: "/profile", label: ru.nav.profile, icon: "user" },
];

/** Inline emergency block shown at the bottom of every phone screen (hidden on desktop: the rail has it). */
export function EmergencyBlock() {
  const { resources, open } = useHelp();
  return (
    <section className="sosblock" aria-label={ru.help.block}>
      <button type="button" className="sosblock__head" onClick={open}>
        <span className="sosblock__icon">
          <Icon name="phone" size={18} />
        </span>
        <span>{ru.help.block}</span>
        <Icon name="chevronRight" size={20} />
      </button>
      <div className="sosblock__lines">
        {resources.slice(0, 2).map((r) => (
          <HotlineCard key={r.phone} r={r} size="sm" />
        ))}
      </div>
    </section>
  );
}

function Sidebar({ signedIn }: { signedIn: boolean }) {
  const { open } = useHelp();
  const { unread } = useDialog();
  return (
    <nav className="sidebar" aria-label="Разделы">
      <Link to={signedIn ? "/today" : "/"} className="sidebar__brand">
        <LogoMark />
        <span>
          <span className="sidebar__name">{ru.product.name}</span>
          <span className="sidebar__tag">{ru.product.tagline}</span>
        </span>
      </Link>
      {signedIn ? (
        <ul className="sidebar__list">
          {TABS.map((t) => (
            <li key={t.to}>
              <NavLink to={t.to} className="sidebar__link">
                <Icon name={t.icon} />
                {t.label}
              </NavLink>
            </li>
          ))}
          <li>
            <NavLink to="/messages" className="sidebar__link">
              <Icon name="message" />
              {ru.nav.messages}
              {unread > 0 && <span className="dot" aria-label="новое" />}
            </NavLink>
          </li>
        </ul>
      ) : (
        <ul className="sidebar__list">
          <li>
            <NavLink to="/" end className="sidebar__link">
              <Icon name="home" />
              {ru.nav.signIn}
            </NavLink>
          </li>
          <li>
            <button type="button" className="sidebar__link" onClick={open}>
              <Icon name="question" />
              {ru.nav.help}
            </button>
          </li>
        </ul>
      )}
      <div className="sidebar__note">
        <strong>{ru.product.supportTitle}</strong>
        <span>{ru.product.supportText}</span>
      </div>
    </nav>
  );
}

function BottomNav() {
  return (
    <nav className="tabbar" aria-label="Разделы">
      {TABS.map((t) => (
        <NavLink key={t.to} to={t.to} className="tabbar__item">
          <Icon name={t.icon} />
          <span>{t.label}</span>
        </NavLink>
      ))}
    </nav>
  );
}

function Rail({ aside }: { aside?: ReactNode }) {
  const { resources, open } = useHelp();
  return (
    <aside className="rail">
      {aside}
      <section className="railsos" aria-label={ru.help.block}>
        <button type="button" className="railsos__head" onClick={open}>
          <Icon name="phone" size={18} />
          <span>{ru.help.block}</span>
        </button>
        {resources.map((r) => (
          <HotlineCard key={r.phone} r={r} size="sm" />
        ))}
      </section>
    </aside>
  );
}

function WorkspaceHeader({ signedIn, bare = false }: { signedIn: boolean; bare?: boolean }) {
  const { session } = useSession();
  return (
    <header className={`workspace${bare ? " workspace--bare" : ""}`}>
      <div className="workspace__brand">
        <LogoMark size={30} />
        <span>{bare ? ru.product.name : signedIn ? ru.product.workspace : ru.nav.signIn}</span>
      </div>
      {signedIn && !bare ? (
        <Link className="workspace__profile" to="/profile">
          <span className="avatar"><Icon name="user" size={18} /></span>
          <span>{session?.displayName || ru.nav.profile}</span>
        </Link>
      ) : <span className="workspace__tag">{ru.product.tagline}</span>}
    </header>
  );
}

export function AppShell({
  children,
  signedIn = true,
  aside,
  focus = false,
  sos = true,
  bare = false,
}: {
  children: ReactNode;
  signedIn?: boolean;
  aside?: ReactNode;
  /** Focus screens (one question per screen) hide the tab bar on phones, like in the mocks. */
  focus?: boolean;
  /** The crisis screen shows the hotlines itself, so it drops the bottom block. */
  sos?: boolean;
  /** Questionnaires: no sidebar, rail or tab bar — one centred column, so nothing distracts from the answers. */
  bare?: boolean;
}) {
  if (bare)
    return (
      <div className="app app--bare">
        <div className="app__main">
          <WorkspaceHeader signedIn={signedIn} bare />
          <main className="screen" id="main">
            {children}
            {sos && <EmergencyBlock />}
          </main>
        </div>
      </div>
    );
  return (
    <div className={`app${signedIn && !focus ? " app--tabs" : ""}`}>
      <Sidebar signedIn={signedIn} />
      <div className="app__main">
        <WorkspaceHeader signedIn={signedIn} />
        <main className="screen" id="main">
          {children}
          {sos && <EmergencyBlock />}
        </main>
        <Rail aside={aside} />
      </div>
      {signedIn && !focus && <BottomNav />}
    </div>
  );
}

export function Notice({ tone = "info", children }: { tone?: "info" | "warn" | "danger" | "ok"; children: ReactNode }) {
  const icon: IconName = tone === "info" ? "info" : tone === "ok" ? "check" : tone === "danger" ? "x" : "alert";
  return (
    <div className={`notice notice--${tone}`} role="note">
      <Icon name={icon} />
      <div>{children}</div>
    </div>
  );
}

export function TopBar({ onBack, title, children }: { onBack?: () => void; title?: string; children?: ReactNode }) {
  return (
    <div className="topbar">
      {onBack && (
        <button type="button" className="icon-btn" onClick={onBack} aria-label={ru.common.back}>
          <Icon name="arrowLeft" />
        </button>
      )}
      {title && <span className="topbar__title">{title}</span>}
      {children}
    </div>
  );
}