export async function introspectGuildToken(token: string): Promise<{ active: boolean; user?: { id: string; email?: string } }> {
  const centerBaseUrl = process.env.FABRIC_BACKEND_GUILD_CENTER_BASE_URL;
  const guildNodeId = process.env.FABRIC_BACKEND_GUILD_NODE_ID;
  const centerApiKey = process.env.FABRIC_BACKEND_GUILD_CENTER_API_KEY;

  if (!centerBaseUrl || !guildNodeId || !centerApiKey) {
    return { active: false };
  }

  const res = await fetch(`${centerBaseUrl}/api/auth/introspect`, {
    method: 'POST',
    headers: {
      'content-type': 'application/json',
      'x-api-key': centerApiKey,
    },
    body: JSON.stringify({ token, guildNodeId }),
  });

  if (!res.ok) return { active: false };
  const data = (await res.json()) as { active?: boolean; user?: { id: string; email?: string } };
  if (!data.active) return { active: false };

  return {
    active: true,
    user: data.user,
  };
}

/**
 * Fetch the single Center-scoped admin user (if any).
 * Same x-api-key auth as introspect / resolve-names.
 * Returns `null` when no admin is set OR the request fails (treated
 * identically — the guild simply falls back to "no admin observer").
 */
export async function fetchAdminEmail(): Promise<{ email: string; userId: string } | null> {
  const centerBaseUrl = process.env.FABRIC_BACKEND_GUILD_CENTER_BASE_URL;
  const centerApiKey = process.env.FABRIC_BACKEND_GUILD_CENTER_API_KEY;
  if (!centerBaseUrl || !centerApiKey) return null;

  try {
    const res = await fetch(`${centerBaseUrl}/api/auth/admin-email`, {
      method: 'GET',
      headers: { 'x-api-key': centerApiKey },
    });
    if (!res.ok) return null;
    const data = (await res.json()) as { email?: string; userId?: string } | null;
    if (!data || !data.email || !data.userId) return null;
    return { email: data.email, userId: data.userId };
  } catch {
    return null;
  }
}

// Resolve <@user.name:NAME> names to userIds within this guild node via
// Center. Unresolved names are simply absent from the returned map.
export async function resolveUserNames(names: string[]): Promise<Record<string, string>> {
  const centerBaseUrl = process.env.FABRIC_BACKEND_GUILD_CENTER_BASE_URL;
  const guildNodeId = process.env.FABRIC_BACKEND_GUILD_NODE_ID;
  const centerApiKey = process.env.FABRIC_BACKEND_GUILD_CENTER_API_KEY;
  if (!centerBaseUrl || !guildNodeId || !centerApiKey || !names.length) return {};

  try {
    const res = await fetch(`${centerBaseUrl}/api/auth/resolve-names`, {
      method: 'POST',
      headers: { 'content-type': 'application/json', 'x-api-key': centerApiKey },
      body: JSON.stringify({ guildNodeId, names }),
    });
    if (!res.ok) return {};
    const data = (await res.json()) as { resolved?: Record<string, string> };
    return data.resolved ?? {};
  } catch {
    return {};
  }
}