import type { OpenClawPluginApi } from "openclaw/plugin-sdk";

function userIdFromToken(token: string): string | undefined {
  try {
    const segment = token.split(".")[0];
    const padded = segment + "=".repeat((4 - (segment.length % 4)) % 4);
    return Buffer.from(padded, "base64").toString("utf8");
  } catch {
    return undefined;
  }
}

export function resolveDiscordUserId(api: OpenClawPluginApi, accountId: string): string | undefined {
  const root = (api.config as Record<string, unknown>) || {};
  const channels = (root.channels as Record<string, unknown>) || {};
  const discord = (channels.discord as Record<string, unknown>) || {};
  const accounts = (discord.accounts as Record<string, Record<string, unknown>>) || {};
  const acct = accounts[accountId];
  if (!acct?.token || typeof acct.token !== "string") return undefined;
  return userIdFromToken(acct.token);
}

export type ModeratorMessageResult =
  | { ok: true; status: number; channelId: string; messageId?: string }
  | { ok: false; status?: number; channelId: string; error: string };

export async function sendModeratorMessage(
  token: string,
  channelId: string,
  content: string,
  logger: { info: (msg: string) => void; warn: (msg: string) => void },
): Promise<ModeratorMessageResult> {
  try {
    const r = await fetch(`https://discord.com/api/v10/channels/${channelId}/messages`, {
      method: "POST",
      headers: {
        Authorization: `Bot ${token}`,
        "Content-Type": "application/json",
      },
      body: JSON.stringify({ content }),
    });

    const text = await r.text();
    let json: Record<string, unknown> | null = null;
    try {
      json = text ? (JSON.parse(text) as Record<string, unknown>) : null;
    } catch {
      json = null;
    }

    if (!r.ok) {
      const error = `discord api error (${r.status}): ${text || "<empty response>"}`;
      logger.warn(`dirigent: moderator send failed channel=${channelId} ${error}`);
      return { ok: false, status: r.status, channelId, error };
    }

    const messageId = typeof json?.id === "string" ? json.id : undefined;
    logger.info(`dirigent: moderator message sent to channel=${channelId} messageId=${messageId ?? "unknown"}`);
    return { ok: true, status: r.status, channelId, messageId };
  } catch (err) {
    const error = String(err);
    logger.warn(`dirigent: moderator send error channel=${channelId}: ${error}`);
    return { ok: false, channelId, error };
  }
}