import * as tc from "@actions/tool-cache";
import * as core from "@actions/core";
import * as cp from "child_process";
import * as path from "path";
import * as fs from "fs";
import { verifyChecksum } from "./checksum";
import { EOL } from "os";
import { ARM64_RUNNER_MESSAGE, ARM64_WINDOWS_RUNNER_MESSAGE } from "./common";
import { chownForFolder } from "./utils";

export async function installAgent(
  isTLS: boolean,
  configStr: string
): Promise<boolean> {
  // Note: to avoid github rate limiting
  const token = core.getInput("token", { required: true });
  const auth = `token ${token}`;

  const variant = process.arch === "x64" ? "amd64" : "arm64";

  let downloadPath: string;

  fs.appendFileSync(process.env.GITHUB_STATE, `isTLS=${isTLS}${EOL}`, {
    encoding: "utf8",
  });

  if (isTLS) {
    downloadPath = await tc.downloadTool(
      `https://github.com/step-security/agent-ebpf/releases/download/v1.7.15/harden-runner_1.7.15_linux_${variant}.tar.gz`,
      undefined,
      auth
    );
  } else {
    if (variant === "arm64") {
      console.log(ARM64_RUNNER_MESSAGE);
      return false;
    }
    downloadPath = await tc.downloadTool(
      "https://github.com/step-security/agent/releases/download/v0.15.0/agent_0.15.0_linux_amd64.tar.gz",
      undefined,
      auth
    );
  }

  if (!verifyChecksum(downloadPath, isTLS, variant, "linux")) {
    return false;
  }

  const extractPath = await tc.extractTar(downloadPath);

  let cmd = "cp",
    args = [path.join(extractPath, "agent"), "/home/agent/agent"];

  cp.execFileSync(cmd, args);

  cp.execSync("chmod +x /home/agent/agent");

  fs.writeFileSync("/home/agent/agent.json", configStr);

  cmd = "sudo";
  args = [
    "cp",
    path.join(__dirname, "agent.service"),
    "/etc/systemd/system/agent.service",
  ];
  cp.execFileSync(cmd, args);
  cp.execSync("sudo systemctl daemon-reload");
  cp.execSync("sudo service agent start", { timeout: 15000 });
  return true;
}

export async function installMacosAgent(configStr: string): Promise<boolean> {
  const token = core.getInput("token", { required: true });
  const auth = `token ${token}`;

  try {
    // Create working directory
    core.info("Creating /opt/step-security directory...");
    cp.execSync("sudo mkdir -p /opt/step-security");
    chownForFolder(process.env.USER, "/opt/step-security");
    core.info("✓ Successfully created /opt/step-security directory");

    // Create agent configuration file
    core.info("Creating agent.json");
    fs.writeFileSync("/opt/step-security/agent.json", configStr);
    core.info(
      "✓ Successfully created agent.json at /opt/step-security/agent.json"
    );

    // Download installer package
    const downloadUrl =
      "https://github.com/step-security/agent-releases/releases/download/v0.0.4-mac/macos-installer-0.0.4.tar.gz";
    core.info(`Downloading macOS installer.. : ${downloadUrl}`);
    const downloadPath = await tc.downloadTool(downloadUrl, undefined, auth);
    core.info(`✓ Successfully downloaded installer to: ${downloadPath}`);

    // Verify SHA256 checksum
    core.info("Verifying SHA256 checksum of downloaded tar file...");
    if (!verifyChecksum(downloadPath, false, "", "darwin")) {
      return false;
    }

    // Extract installer package
    core.info("Extracting installer...");
    const extractPath = await tc.extractTar(downloadPath);
    core.info(`✓ Successfully extracted installer to: ${extractPath}`);

    // Copy Installer binary to /opt/step-security
    const installerSourcePath = path.join(extractPath, "Installer");
    const installerBinaryPath = "/opt/step-security/Installer";

    core.info(
      `Copying Installer from ${installerSourcePath} to /opt/step-security...`
    );
    cp.execFileSync("cp", [installerSourcePath, installerBinaryPath]);
    core.info("✓ Successfully copied Installer to /opt/step-security");


    // Verify installer binary exists
    if (!fs.existsSync(installerBinaryPath)) {
      throw new Error(
        "Installer binary not found at /opt/step-security/Installer"
      );
    }
    core.info("✓ Installer binary verified");

    // Make installer executable
    core.info("Making installer executable...");
    cp.execSync(`chmod +x "${installerBinaryPath}"`);
    core.info("✓ Installer is now executable");

    // Run installer
    core.info("Running installer...");
    cp.execSync(
      `sudo "${installerBinaryPath}" -workdir /opt/step-security >> /opt/step-security/agent.log 2>&1`,
      {
        shell: "/bin/bash",
        timeout: 10000, // 10 second timeout
      }
    );
    core.info("✓ Installer completed successfully");

    core.info("✅ macOS agent installation completed successfully");
    return true;
  } catch (error) {
    core.error(`❌ Failed to install macOS agent: ${error}`);
    if (error instanceof Error && error.stack) {
      core.debug(error.stack);
    }
    return false;
  }
}

export async function installWindowsAgent(configStr: string): Promise<boolean> {
  const token = core.getInput("token", { required: true });
  const auth = `token ${token}`;

  const variant = process.arch === "x64" ? "amd64" : "arm64";
  if (variant === "arm64") {
    console.log(ARM64_WINDOWS_RUNNER_MESSAGE);
    return false;
  }

  const agentDir = "C:\\agent";
  core.info(`Creating agent directory: ${agentDir}`);
  if (!fs.existsSync(agentDir)) {
    fs.mkdirSync(agentDir, { recursive: true });
  }
  fs.appendFileSync(process.env.GITHUB_STATE, `agentDir=${agentDir}${EOL}`, {
    encoding: "utf8",
  });
  const agentExePath = path.join(agentDir, "agent.exe");

  const downloadPath = await tc.downloadTool(
    `https://github.com/step-security/agent-releases/releases/download/v1.0.0-win/harden-runner-agent-windows_1.0.0_windows_amd64.tar.gz`,
    undefined,
    auth
  );

  // validate the checksum
  if (!verifyChecksum(downloadPath, false, variant, process.platform)) {
    return false;
  }

  const extractPath = await tc.extractTar(downloadPath);

  const extractedAgentPath = path.join(extractPath, "agent.exe");
  fs.copyFileSync(extractedAgentPath, agentExePath);
  core.info(`Copied agent from ${extractedAgentPath} to ${agentExePath}`);

  const configPath = path.join(agentDir, "config.json");
  fs.writeFileSync(configPath, configStr);
  core.info(`Created config file: ${configPath}`);

  core.info("Starting Windows Agent...");

  try {
    const logPath = path.join(agentDir, "agent.log");
    const logStream = fs.openSync(logPath, "a");
    core.info(`Agent logs will be written to: ${logPath}`);

    const agentProcess = cp.spawn(agentExePath, [], {
      cwd: agentDir,
      detached: true,
      stdio: ["ignore", logStream, logStream],
      windowsHide: false,
      shell: false,
    });

    const pidFile = path.join(agentDir, "agent.pid");
    fs.writeFileSync(pidFile, agentProcess.pid.toString());
    core.info(`Agent process started with PID: ${agentProcess.pid}`);
    core.info(`PID saved to: ${pidFile}`);

    agentProcess.unref();

    core.info("Windows Agent process started successfully");
    return true;
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : String(error);
    core.setFailed(`Failed to start Windows agent process: ${errorMessage}`);
    return false;
  }
}