/**
 * ConnectDialog — broker connection + session lobby (list / create / join)
 *
 * The broker connection and the active session are decoupled: this dialog
 * connects to the broker, which makes the session list available, and joining
 * or creating a session is a separate step that reuses that connection.
 */
import { Component, createSignal, For, onMount, Show } from "solid-js";
import { TbOutlineTrash } from "solid-icons/tb";
import {
  connectBroker,
  createSession,
  joinSession,
  resolveBrokerUrl,
  sessions,
  setMyName,
  setMyRole,
  useJournalStream,
} from "../stores/journalStream";
import { DeleteSessionDialog } from "./DeleteSessionDialog";

export const ConnectDialog: Component = () => {
  const stream = useJournalStream();
  const manifest = sessions;
  const [playerName, setPlayerName] = createSignal(stream.myName);
  const [role, setRole] = createSignal<"gm" | "player" | "observer">(
    stream.myRole,
  );
  const [newSessionName, setNewSessionName] = createSignal("");
  const [busy, setBusy] = createSignal(false);
  const [error, setError] = createSignal<string | null>(null);
  const [autoJoined, setAutoJoined] = createSignal(false);
  const [sessionToDelete, setSessionToDelete] = createSignal<{
    id: string;
    name: string;
  } | null>(null);

  const ensureBroker = async () => {
    if (stream.connected) return;
    await connectBroker(resolveBrokerUrl());
  };

  const identity = () => ({
    name: playerName().trim() || stream.myName,
    role: role(),
  });

  const applyIdentity = () => {
    const { name, role: r } = identity();
    setMyName(name);
    setMyRole(r);
  };

  const handleJoin = async (sessionId: string) => {
    setBusy(true);
    setError(null);
    try {
      applyIdentity();
      await ensureBroker();
      await joinSession(sessionId, identity());
    } catch (e) {
      setError(e instanceof Error ? e.message : "Connection failed");
    } finally {
      setBusy(false);
    }
  };

  const handleCreate = async () => {
    const name = newSessionName().trim();
    if (!name) return;
    setBusy(true);
    setError(null);
    try {
      applyIdentity();
      await ensureBroker();
      const id = await createSession(name);
      if (id) await joinSession(id, identity());
      setNewSessionName("");
    } catch (e) {
      setError(e instanceof Error ? e.message : "Connection failed");
    } finally {
      setBusy(false);
    }
  };

  // Auto-join when the URL carries session + player + autojoin params;
  // otherwise enter the lobby so the session list is available up front.
  onMount(() => {
    const params = new URL(window.location.href).searchParams;
    if (
      params.has("session") &&
      params.has("player") &&
      params.has("autojoin")
    ) {
      setPlayerName(params.get("player") || "");
      setRole("player");
      setAutoJoined(true);
      handleJoin(params.get("session")!);
      return;
    }
    ensureBroker().catch((e) => {
      setError(e instanceof Error ? e.message : "Connection failed");
    });
  });

  return (
    <Show
      when={!autoJoined() || error()}
      fallback={
        <p class="text-sm text-gray-500 text-center">
          {busy() ? "正在加入会话…" : "已加入！"}
        </p>
      }
    >
      <div class="w-full max-w-sm space-y-3">
        <p class="text-sm text-gray-600 text-center">
          输入你的名字和角色，选择或新建一个会话。
          <br />
          <span class="text-xs text-gray-400">
            连接到 {window.location.host}
          </span>
        </p>
        <input
          type="text"
          value={playerName()}
          onInput={(e) => setPlayerName(e.currentTarget.value)}
          onKeyDown={(e) => e.key === "Enter" && handleCreate()}
          placeholder="你的名字"
          class="w-full border border-gray-300 rounded px-3 py-1.5 text-sm"
          autofocus
        />
        {/* Role selector */}
        <div class="flex gap-1">
          {(["gm", "player", "observer"] as const).map((r) => (
            <button
              onClick={() => setRole(r)}
              class={`flex-1 rounded px-2 py-1.5 text-xs font-medium border transition-colors ${
                role() === r
                  ? "bg-blue-600 text-white border-blue-600"
                  : "bg-white text-gray-600 border-gray-300 hover:border-gray-400"
              }`}
            >
              {r === "gm" ? "主持人" : r === "player" ? "玩家" : "观察者"}
            </button>
          ))}
        </div>

        {/* Session list */}
        <div class="space-y-1">
          <p class="text-xs text-gray-500">会话</p>
          <div class="max-h-40 overflow-y-auto border border-gray-200 rounded divide-y divide-gray-100">
            <For each={Object.entries(manifest().sessions)}>
              {([id, meta]) => (
                <div class="flex items-center">
                  <button
                    onClick={() => handleJoin(id)}
                    disabled={busy()}
                    class="flex-1 min-w-0 text-left px-2 py-1.5 text-xs text-gray-700 hover:bg-gray-50 disabled:opacity-50 truncate"
                  >
                    {meta.name || id}
                  </button>
                  <Show when={role() === "gm"}>
                    <button
                      onClick={() =>
                        setSessionToDelete({ id, name: meta.name || id })
                      }
                      disabled={busy()}
                      class="shrink-0 px-2 py-1.5 text-[10px] text-gray-300 hover:text-red-500 disabled:opacity-50"
                      title="删除会话"
                    >
                      <TbOutlineTrash />
                    </button>
                  </Show>
                </div>
              )}
            </For>
            <Show when={Object.keys(manifest().sessions).length === 0}>
              <p class="px-2 py-2 text-xs text-gray-400">
                {stream.connected ? "还没有会话" : "正在加载会话…"}
              </p>
            </Show>
          </div>
        </div>

        {/* Create a new session and join it (GM only) */}
        <Show when={role() === "gm"}>
          <div class="flex gap-1">
            <input
              type="text"
              value={newSessionName()}
              onInput={(e) => setNewSessionName(e.currentTarget.value)}
              onKeyDown={(e) => e.key === "Enter" && handleCreate()}
              placeholder="新会话名称"
              class="flex-1 border border-gray-300 rounded px-2 py-1.5 text-sm"
            />
            <button
              onClick={handleCreate}
              disabled={busy() || !newSessionName().trim()}
              class="bg-blue-600 text-white rounded px-3 py-1.5 text-sm font-medium
                   hover:bg-blue-700 disabled:opacity-50 whitespace-nowrap"
            >
              新建并加入
            </button>
          </div>
        </Show>

        <Show when={error()}>
          <p class="text-red-500 text-sm text-center">{error()}</p>
        </Show>

        <Show when={sessionToDelete()}>
          {(target) => (
            <DeleteSessionDialog
              sessionId={target().id}
              sessionName={target().name}
              active={stream.sessionId === target().id}
              onClose={() => setSessionToDelete(null)}
            />
          )}
        </Show>
      </div>
    </Show>
  );
};