"use client";

import { useEffect, useState } from "react";
import { useRouter } from "next/navigation";
import { createRoom, listCharacters, type CharacterSummary, type RoomMode } from "../../lib/api";

const USER_ID = "seed-user-primary";

// K-7 建房介面：建立後導向 /room/[roomId]（T19-P2 起的通用房間畫面，含 SSE／立繪舞台／語音／靜音，
// 見 T19-P3），不再自己維護一份較舊、功能較少的房間顯示邏輯。
export function RoomView() {
  const router = useRouter();
  const [characters, setCharacters] = useState<CharacterSummary[]>([]);
  const [selectedCharacterIds, setSelectedCharacterIds] = useState<string[]>([]);
  const [mode, setMode] = useState<RoomMode>("GROUP");
  const [topicSeed, setTopicSeed] = useState("");
  const [pending, setPending] = useState(false);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    void listCharacters().then(setCharacters);
  }, []);

  async function handleCreateRoom() {
    if (selectedCharacterIds.length === 0 || pending) return;
    setPending(true);
    setError(null);
    try {
      const created = await createRoom(USER_ID, selectedCharacterIds, mode, topicSeed || undefined);
      router.push(`/room/${created.id}`);
    } catch {
      setError("房間建立失敗，請確認 api 服務是否已啟動");
      setPending(false);
    }
  }

  return (
    <div className="flex flex-col gap-3 rounded-2xl border p-4" style={{ borderColor: "var(--line)" }}>
      <h2 className="text-sm font-bold" style={{ color: "var(--ink)" }}>
        建立房間
      </h2>
      <div className="flex flex-wrap gap-2 text-xs">
        {characters.map((character) => {
          const checked = selectedCharacterIds.includes(character.id);
          return (
            <label
              key={character.id}
              className="flex items-center gap-1 rounded-full border px-2 py-1"
              style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            >
              <input
                type="checkbox"
                checked={checked}
                onChange={() =>
                  setSelectedCharacterIds((prev) => (checked ? prev.filter((id) => id !== character.id) : [...prev, character.id]))
                }
              />
              {character.aliases[0]?.formalName ?? character.id}
            </label>
          );
        })}
      </div>
      <div className="flex items-center gap-3 text-xs">
        <label className="flex items-center gap-1" style={{ color: "var(--ink)" }}>
          <input type="radio" checked={mode === "GROUP"} onChange={() => setMode("GROUP")} />
          群聊
        </label>
        <label className="flex items-center gap-1" style={{ color: "var(--ink)" }}>
          <input type="radio" checked={mode === "SELF_CHAT"} onChange={() => setMode("SELF_CHAT")} />
          角色自聊（旁觀）
        </label>
      </div>
      <input
        value={topicSeed}
        onChange={(event) => setTopicSeed(event.target.value)}
        placeholder="話題種子（選填）"
        className="rounded-full border bg-transparent px-3 py-1.5 text-xs"
        style={{ borderColor: "var(--line)", color: "var(--ink)" }}
      />
      <button
        type="button"
        onClick={() => void handleCreateRoom()}
        disabled={pending || selectedCharacterIds.length === 0}
        className="self-start rounded-full px-4 py-1.5 text-xs font-bold text-white disabled:opacity-50"
        style={{ background: "var(--accent-bright)" }}
      >
        建立房間
      </button>
      {error && (
        <p className="text-xs" style={{ color: "var(--accent)" }}>
          {error}
        </p>
      )}
    </div>
  );
}