import type { OpenClawPluginApi } from "openclaw/plugin-sdk";
import type { ChannelStore } from "../core/channel-store.js";

type Deps = {
  api: OpenClawPluginApi;
  channelStore: ChannelStore;
  moderatorBotUserId: string | undefined;
  scheduleIdentifier: string;
  moderatorServiceUrl: string | undefined;
  moderatorServiceToken: string | undefined;
  debugMode: boolean;
  onNewMessage: (event: {
    channelId: string;
    messageId: string;
    senderId: string;
    guildId?: string;
  }) => Promise<void>;
};

function sendJson(res: import("node:http").ServerResponse, status: number, payload: unknown): void {
  res.writeHead(status, { "Content-Type": "application/json; charset=utf-8" });
  res.end(JSON.stringify(payload));
}

function readBody(req: import("node:http").IncomingMessage): Promise<Record<string, unknown>> {
  return new Promise((resolve, reject) => {
    let body = "";
    req.on("data", (chunk: Buffer) => {
      body += chunk.toString();
      if (body.length > 1_000_000) {
        req.destroy();
        reject(new Error("body too large"));
      }
    });
    req.on("end", () => {
      try {
        resolve(body ? (JSON.parse(body) as Record<string, unknown>) : {});
      } catch {
        reject(new Error("invalid_json"));
      }
    });
    req.on("error", reject);
  });
}

/**
 * Register Dirigent plugin HTTP routes that the moderator service calls back into.
 *
 * Routes:
 *   POST /dirigent/api/moderator/message  — inbound message notification from moderator service
 *   GET  /dirigent/api/moderator/status   — health/status check
 */
export function registerDirigentApi(deps: Deps): void {
  const { api, moderatorServiceUrl, onNewMessage } = deps;

  // ── POST /dirigent/api/moderator/message ─────────────────────────────────────
  // Called by the moderator service on every Discord MESSAGE_CREATE event.
  api.registerHttpRoute({
    path: "/dirigent/api/moderator/message",
    auth: "plugin",
    match: "exact",
    handler: async (req, res) => {
      if (req.method !== "POST") {
        res.writeHead(405);
        res.end();
        return;
      }

      let body: Record<string, unknown>;
      try {
        body = await readBody(req);
      } catch (err) {
        return sendJson(res, 400, { ok: false, error: String(err) });
      }

      const channelId = typeof body.channelId === "string" ? body.channelId : undefined;
      const messageId = typeof body.messageId === "string" ? body.messageId : undefined;
      const senderId = typeof body.senderId === "string" ? body.senderId : undefined;
      const guildId = typeof body.guildId === "string" ? body.guildId : undefined;

      if (!channelId || !senderId) {
        return sendJson(res, 400, { ok: false, error: "channelId and senderId required" });
      }

      try {
        await onNewMessage({
          channelId,
          messageId: messageId ?? "",
          senderId,
          guildId,
        });
        return sendJson(res, 200, { ok: true });
      } catch (err) {
        api.logger.warn(`dirigent: moderator/message handler error: ${String(err)}`);
        return sendJson(res, 500, { ok: false, error: String(err) });
      }
    },
  });

  // ── GET /dirigent/api/moderator/status ───────────────────────────────────────
  api.registerHttpRoute({
    path: "/dirigent/api/moderator/status",
    auth: "plugin",
    match: "exact",
    handler: (_req, res) => {
      return sendJson(res, 200, {
        ok: true,
        moderatorServiceUrl: moderatorServiceUrl ?? null,
      });
    },
  });
}