import path from "node:path";
import type { Command } from "commander";

import {
  DEFAULT_GATEWAY_DAEMON_RUNTIME,
  isGatewayDaemonRuntime,
} from "../commands/daemon-runtime.js";
import { loadConfig, resolveGatewayPort } from "../config/config.js";
import { resolveIsNixMode } from "../config/paths.js";
import {
  GATEWAY_LAUNCH_AGENT_LABEL,
  GATEWAY_SYSTEMD_SERVICE_NAME,
  GATEWAY_WINDOWS_TASK_NAME,
} from "../daemon/constants.js";
import {
  type FindExtraGatewayServicesOptions,
  findExtraGatewayServices,
} from "../daemon/inspect.js";
import { findLegacyGatewayServices } from "../daemon/legacy.js";
import { resolveGatewayProgramArguments } from "../daemon/program-args.js";
import { resolveGatewayService } from "../daemon/service.js";
import { callGateway } from "../gateway/call.js";
import { defaultRuntime } from "../runtime.js";
import { createDefaultDeps } from "./deps.js";

type DaemonStatus = {
  service: {
    label: string;
    loaded: boolean;
    loadedText: string;
    notLoadedText: string;
    command?: {
      programArguments: string[];
      workingDirectory?: string;
    } | null;
  };
  rpc?: {
    ok: boolean;
    error?: string;
  };
  legacyServices: Array<{ label: string; detail: string }>;
  extraServices: Array<{ label: string; detail: string; scope: string }>;
};

export type GatewayRpcOpts = {
  url?: string;
  token?: string;
  password?: string;
  timeout?: string;
};

export type DaemonStatusOptions = {
  rpc: GatewayRpcOpts;
  probe: boolean;
  json: boolean;
} & FindExtraGatewayServicesOptions;

export type DaemonInstallOptions = {
  port?: string | number;
  runtime?: string;
  token?: string;
};

function parsePort(raw: unknown): number | null {
  if (raw === undefined || raw === null) return null;
  const value =
    typeof raw === "string"
      ? raw
      : typeof raw === "number" || typeof raw === "bigint"
        ? raw.toString()
        : null;
  if (value === null) return null;
  const parsed = Number.parseInt(value, 10);
  if (!Number.isFinite(parsed) || parsed <= 0) return null;
  return parsed;
}

async function probeGatewayStatus(opts: GatewayRpcOpts) {
  try {
    await callGateway({
      url: opts.url,
      token: opts.token,
      password: opts.password,
      method: "status",
      timeoutMs: Number(opts.timeout ?? 10_000),
      clientName: "cli",
      mode: "cli",
    });
    return { ok: true } as const;
  } catch (err) {
    return {
      ok: false,
      error: err instanceof Error ? err.message : String(err),
    } as const;
  }
}

function renderGatewayServiceStartHints(): string[] {
  switch (process.platform) {
    case "darwin":
      return [
        `launchctl bootstrap gui/$UID ~/Library/LaunchAgents/${GATEWAY_LAUNCH_AGENT_LABEL}.plist`,
      ];
    case "linux":
      return [`systemctl --user start ${GATEWAY_SYSTEMD_SERVICE_NAME}.service`];
    case "win32":
      return [`schtasks /Run /TN "${GATEWAY_WINDOWS_TASK_NAME}"`];
    default:
      return [];
  }
}

function renderGatewayServiceCleanupHints(): string[] {
  switch (process.platform) {
    case "darwin":
      return [
        `launchctl bootout gui/$UID/${GATEWAY_LAUNCH_AGENT_LABEL}`,
        `rm ~/Library/LaunchAgents/${GATEWAY_LAUNCH_AGENT_LABEL}.plist`,
      ];
    case "linux":
      return [
        `systemctl --user disable --now ${GATEWAY_SYSTEMD_SERVICE_NAME}.service`,
        `rm ~/.config/systemd/user/${GATEWAY_SYSTEMD_SERVICE_NAME}.service`,
      ];
    case "win32":
      return [`schtasks /Delete /TN "${GATEWAY_WINDOWS_TASK_NAME}" /F`];
    default:
      return [];
  }
}

async function gatherDaemonStatus(opts: {
  rpc: GatewayRpcOpts;
  probe: boolean;
  deep?: boolean;
}): Promise<DaemonStatus> {
  const service = resolveGatewayService();
  const [loaded, command] = await Promise.all([
    service.isLoaded({ env: process.env }).catch(() => false),
    service.readCommand(process.env).catch(() => null),
  ]);
  const legacyServices = await findLegacyGatewayServices(process.env);
  const extraServices = await findExtraGatewayServices(process.env, {
    deep: opts.deep,
  });
  const rpc = opts.probe ? await probeGatewayStatus(opts.rpc) : undefined;

  return {
    service: {
      label: service.label,
      loaded,
      loadedText: service.loadedText,
      notLoadedText: service.notLoadedText,
      command,
    },
    rpc,
    legacyServices,
    extraServices,
  };
}

function printDaemonStatus(status: DaemonStatus, opts: { json: boolean }) {
  if (opts.json) {
    defaultRuntime.log(JSON.stringify(status, null, 2));
    return;
  }

  const { service, rpc, legacyServices, extraServices } = status;
  defaultRuntime.log(
    `Service: ${service.label} (${service.loaded ? service.loadedText : service.notLoadedText})`,
  );
  if (service.command?.programArguments?.length) {
    defaultRuntime.log(
      `Command: ${service.command.programArguments.join(" ")}`,
    );
  }
  if (service.command?.workingDirectory) {
    defaultRuntime.log(`Working dir: ${service.command.workingDirectory}`);
  }
  if (rpc) {
    if (rpc.ok) {
      defaultRuntime.log("RPC probe: ok");
    } else {
      defaultRuntime.error(`RPC probe: failed (${rpc.error})`);
    }
  }

  if (legacyServices.length > 0) {
    defaultRuntime.error("Legacy Clawdis services detected:");
    for (const svc of legacyServices) {
      defaultRuntime.error(`- ${svc.label} (${svc.detail})`);
    }
    defaultRuntime.error("Cleanup: clawdbot doctor");
  }

  if (extraServices.length > 0) {
    defaultRuntime.error("Other gateway-like services detected (best effort):");
    for (const svc of extraServices) {
      defaultRuntime.error(`- ${svc.label} (${svc.scope}, ${svc.detail})`);
    }
    for (const hint of renderGatewayServiceCleanupHints()) {
      defaultRuntime.error(`Cleanup hint: ${hint}`);
    }
  }

  if (legacyServices.length > 0 || extraServices.length > 0) {
    defaultRuntime.error(
      "Recommendation: run a single gateway per machine. One gateway supports multiple agents.",
    );
    defaultRuntime.error(
      "If you need multiple gateways, isolate ports + config/state (see docs: /gateway#multiple-gateways-same-host).",
    );
  }
}

export async function runDaemonStatus(opts: DaemonStatusOptions) {
  try {
    const status = await gatherDaemonStatus({
      rpc: opts.rpc,
      probe: Boolean(opts.probe),
      deep: Boolean(opts.deep),
    });
    printDaemonStatus(status, { json: Boolean(opts.json) });
  } catch (err) {
    defaultRuntime.error(`Daemon status failed: ${String(err)}`);
    defaultRuntime.exit(1);
  }
}

export async function runDaemonInstall(opts: DaemonInstallOptions) {
  if (resolveIsNixMode(process.env)) {
    defaultRuntime.error("Nix mode detected; daemon install is disabled.");
    defaultRuntime.exit(1);
    return;
  }

  const cfg = loadConfig();
  const portOverride = parsePort(opts.port);
  if (opts.port !== undefined && portOverride === null) {
    defaultRuntime.error("Invalid port");
    defaultRuntime.exit(1);
    return;
  }
  const port = portOverride ?? resolveGatewayPort(cfg);
  if (!Number.isFinite(port) || port <= 0) {
    defaultRuntime.error("Invalid port");
    defaultRuntime.exit(1);
    return;
  }
  const runtimeRaw = opts.runtime
    ? String(opts.runtime)
    : DEFAULT_GATEWAY_DAEMON_RUNTIME;
  if (!isGatewayDaemonRuntime(runtimeRaw)) {
    defaultRuntime.error('Invalid --runtime (use "node" or "bun")');
    defaultRuntime.exit(1);
    return;
  }

  const service = resolveGatewayService();
  let loaded = false;
  try {
    loaded = await service.isLoaded({ env: process.env });
  } catch (err) {
    defaultRuntime.error(`Gateway service check failed: ${String(err)}`);
    defaultRuntime.exit(1);
    return;
  }
  if (loaded) {
    defaultRuntime.log(`Gateway service already ${service.loadedText}.`);
    return;
  }

  const devMode =
    process.argv[1]?.includes(`${path.sep}src${path.sep}`) &&
    process.argv[1]?.endsWith(".ts");
  const { programArguments, workingDirectory } =
    await resolveGatewayProgramArguments({
      port,
      dev: devMode,
      runtime: runtimeRaw,
    });
  const environment: Record<string, string | undefined> = {
    PATH: process.env.PATH,
    CLAWDBOT_GATEWAY_TOKEN:
      opts.token ||
      cfg.gateway?.auth?.token ||
      process.env.CLAWDBOT_GATEWAY_TOKEN,
    CLAWDBOT_LAUNCHD_LABEL:
      process.platform === "darwin" ? GATEWAY_LAUNCH_AGENT_LABEL : undefined,
  };

  try {
    await service.install({
      env: process.env,
      stdout: process.stdout,
      programArguments,
      workingDirectory,
      environment,
    });
  } catch (err) {
    defaultRuntime.error(`Gateway install failed: ${String(err)}`);
    defaultRuntime.exit(1);
  }
}

export async function runDaemonUninstall() {
  if (resolveIsNixMode(process.env)) {
    defaultRuntime.error("Nix mode detected; daemon uninstall is disabled.");
    defaultRuntime.exit(1);
    return;
  }

  const service = resolveGatewayService();
  try {
    await service.uninstall({ env: process.env, stdout: process.stdout });
  } catch (err) {
    defaultRuntime.error(`Gateway uninstall failed: ${String(err)}`);
    defaultRuntime.exit(1);
  }
}

export async function runDaemonStart() {
  const service = resolveGatewayService();
  let loaded = false;
  try {
    loaded = await service.isLoaded({ env: process.env });
  } catch (err) {
    defaultRuntime.error(`Gateway service check failed: ${String(err)}`);
    defaultRuntime.exit(1);
    return;
  }
  if (!loaded) {
    defaultRuntime.log(`Gateway service ${service.notLoadedText}.`);
    for (const hint of renderGatewayServiceStartHints()) {
      defaultRuntime.log(`Start with: ${hint}`);
    }
    return;
  }
  try {
    await service.restart({ stdout: process.stdout });
  } catch (err) {
    defaultRuntime.error(`Gateway start failed: ${String(err)}`);
    for (const hint of renderGatewayServiceStartHints()) {
      defaultRuntime.error(`Start with: ${hint}`);
    }
    defaultRuntime.exit(1);
  }
}

export async function runDaemonStop() {
  const service = resolveGatewayService();
  let loaded = false;
  try {
    loaded = await service.isLoaded({ env: process.env });
  } catch (err) {
    defaultRuntime.error(`Gateway service check failed: ${String(err)}`);
    defaultRuntime.exit(1);
    return;
  }
  if (!loaded) {
    defaultRuntime.log(`Gateway service ${service.notLoadedText}.`);
    return;
  }
  try {
    await service.stop({ stdout: process.stdout });
  } catch (err) {
    defaultRuntime.error(`Gateway stop failed: ${String(err)}`);
    defaultRuntime.exit(1);
  }
}

export async function runDaemonRestart() {
  const service = resolveGatewayService();
  let loaded = false;
  try {
    loaded = await service.isLoaded({ env: process.env });
  } catch (err) {
    defaultRuntime.error(`Gateway service check failed: ${String(err)}`);
    defaultRuntime.exit(1);
    return;
  }
  if (!loaded) {
    defaultRuntime.log(`Gateway service ${service.notLoadedText}.`);
    for (const hint of renderGatewayServiceStartHints()) {
      defaultRuntime.log(`Start with: ${hint}`);
    }
    return;
  }
  try {
    await service.restart({ stdout: process.stdout });
  } catch (err) {
    defaultRuntime.error(`Gateway restart failed: ${String(err)}`);
    defaultRuntime.exit(1);
  }
}

export function registerDaemonCli(program: Command) {
  const daemon = program
    .command("daemon")
    .description(
      "Manage the Gateway daemon service (launchd/systemd/schtasks)",
    );

  daemon
    .command("status")
    .description("Show daemon install status + probe the Gateway")
    .option(
      "--url <url>",
      "Gateway WebSocket URL (defaults to config/remote/local)",
    )
    .option("--token <token>", "Gateway token (if required)")
    .option("--password <password>", "Gateway password (password auth)")
    .option("--timeout <ms>", "Timeout in ms", "10000")
    .option("--no-probe", "Skip RPC probe")
    .option("--deep", "Scan system-level services", false)
    .option("--json", "Output JSON", false)
    .action(async (opts) => {
      await runDaemonStatus({
        rpc: opts,
        probe: Boolean(opts.probe),
        deep: Boolean(opts.deep),
        json: Boolean(opts.json),
      });
    });

  daemon
    .command("install")
    .description("Install the Gateway service (launchd/systemd/schtasks)")
    .option("--port <port>", "Gateway port")
    .option("--runtime <runtime>", "Daemon runtime (node|bun). Default: node")
    .option("--token <token>", "Gateway token (token auth)")
    .action(async (opts) => {
      await runDaemonInstall(opts);
    });

  daemon
    .command("uninstall")
    .description("Uninstall the Gateway service (launchd/systemd/schtasks)")
    .action(async () => {
      await runDaemonUninstall();
    });

  daemon
    .command("start")
    .description("Start the Gateway service (launchd/systemd/schtasks)")
    .action(async () => {
      await runDaemonStart();
    });

  daemon
    .command("stop")
    .description("Stop the Gateway service (launchd/systemd/schtasks)")
    .action(async () => {
      await runDaemonStop();
    });

  daemon
    .command("restart")
    .description("Restart the Gateway service (launchd/systemd/schtasks)")
    .action(async () => {
      await runDaemonRestart();
    });

  // Build default deps (parity with other commands).
  void createDefaultDeps();
}