import fs from "node:fs";
import net from "node:net";
import path from "node:path";
import type { OpenClawPluginApi } from "openclaw/plugin-sdk";
import { normalizePluginConfig } from "./core/types/contractor.js";
import { resolveContractorAgentMetadata } from "./core/contractor/metadata-resolver.js";
import { createBridgeServer } from "./web/server.js";
import { registerCli } from "./commands/register-cli.js";
import type http from "node:http";

function isPortFree(port: number): Promise<boolean> {
  return new Promise((resolve) => {
    const tester = net.createServer();
    tester.once("error", () => resolve(false));
    tester.once("listening", () => tester.close(() => resolve(true)));
    tester.listen(port, "127.0.0.1");
  });
}

// ── GlobalThis state ─────────────────────────────────────────────────────────
// All persistent state lives on globalThis to survive OpenClaw hot-reloads.
// See LESSONS_LEARNED.md items 1, 3, 11.

const _G = globalThis as Record<string, unknown>;
const LIFECYCLE_KEY = "_contractorAgentLifecycleRegistered";
const SERVER_KEY = "_contractorAgentBridgeServer";
/** Key for the live OpenClaw config accessor (getter fn) shared via globalThis. */
const OPENCLAW_CONFIG_KEY = "_contractorOpenClawConfig";

// ── Plugin entry ─────────────────────────────────────────────────────────────

export default {
  id: "contractor-agent",
  name: "Contractor Agent",
  async register(api: OpenClawPluginApi) {
    const config = normalizePluginConfig(api.pluginConfig);

    // Resolve agent metadata for the bridge server's resolveAgent callback.
    // We do this by reading openclaw.json — the bridge server calls this on every turn.
    function resolveAgent(agentId: string, _sessionKey: string) {
      try {
        const configPath = path.join(
          (process.env.HOME ?? "/root"),
          ".openclaw",
          "openclaw.json",
        );
        const raw = JSON.parse(fs.readFileSync(configPath, "utf8")) as {
          agents?: { list?: Array<{ id: string; workspace?: string; model?: string }> };
        };
        const agent = raw.agents?.list?.find((a) => a.id === agentId);
        if (!agent) return null;
        const meta = resolveContractorAgentMetadata(agent, config.permissionMode);
        if (!meta) return null;
        return { workspace: meta.workspace };
      } catch {
        return null;
      }
    }

    // ── Gateway lifecycle (start bridge server once per gateway process) ──────
    // Guard with globalThis flag AND a port probe to handle the case where the
    // gateway is already running the server while a CLI subprocess is starting up.
    // (See LESSONS_LEARNED.md item 7 — lock file / port probe pattern)
    // Always update the config accessor so hot-reloads get fresh config.
    // server.ts reads this via globalThis to build tool execution context.
    _G[OPENCLAW_CONFIG_KEY] = api.config;

    if (!_G[LIFECYCLE_KEY]) {
      _G[LIFECYCLE_KEY] = true;

      // Only bind if port is not already in use (avoids EADDRINUSE in CLI mode)
      const portFree = await isPortFree(config.bridgePort);
      if (!portFree) {
        api.logger.info(
          `[contractor-agent] bridge already running on port ${config.bridgePort}, skipping bind`,
        );
        return;
      }

      const server = createBridgeServer({
        port: config.bridgePort,
        apiKey: config.bridgeApiKey,
        permissionMode: config.permissionMode,
        resolveAgent,
        logger: api.logger,
      });
      _G[SERVER_KEY] = server;

      api.on("gateway_stop", () => {
        const s = _G[SERVER_KEY] as http.Server | undefined;
        if (s) s.close();
        api.logger.info("[contractor-agent] bridge server stopped");
      });
    }

    // ── CLI ───────────────────────────────────────────────────────────────────
    registerCli(api);

    api.logger.info(`[contractor-agent] plugin registered (bridge port: ${config.bridgePort})`);
  },
};