import { readFile } from "node:fs/promises";
import path from "node:path";
import { Alpine } from "../alpine.js";

export class Runit {
  alpine: Alpine;
  private constructor({ alpine }: { alpine: Alpine }) {
    this.alpine = alpine;
  }

  private static async getScript(name: string): Promise<string> {
    return await readFile(path.join("runit/scripts", name), "utf8");
  }

  static async setup(alpine: Alpine): Promise<Runit> {
    await alpine.mkdirP("/etc/runit/runsvdir/default");
    await alpine.symlink(
      "/etc/runit/runsvdir/default",
      "/etc/runit/runsvdir/current"
    );
    await alpine.symlink("/etc/runit/runsvdir/current", "/etc/service");
    await alpine.symlink("/run/runit/stopit", "/etc/runit/stopit");
    await alpine.symlink("/run/runit/reboot", "/etc/runit/reboot");

    // Estos scripts fueron robados de Void Linux
    await alpine.writeExecutable(
      "/etc/runit/functions",
      await this.getScript("functions")
    );

    await alpine.writeExecutable(
      "/etc/runit/core-services/00-pseudofs.sh",
      await this.getScript("00-pseudofs.sh")
    );
    await alpine.writeExecutable(
      "/etc/runit/core-services/01-static-devnodes.sh",
      await this.getScript("01-static-devnodes.sh")
    );
    await alpine.writeExecutable(
      "/etc/runit/core-services/02-udev.sh",
      await this.getScript("02-udev.sh")
    );
    await alpine.writeExecutable(
      "/etc/runit/core-services/03-filesystems.sh",
      await this.getScript("03-filesystems.sh")
    );
    await alpine.writeExecutable(
      "/etc/runit/core-services/04-swap.sh",
      await this.getScript("04-swap.sh")
    );
    await alpine.writeExecutable(
      "/etc/runit/core-services/05-misc.sh",
      await this.getScript("05-misc.sh")
    );

    for (let stage = 1; stage <= 3; stage++)
      await alpine.writeExecutable(
        "/etc/runit/" + stage,
        await this.getScript("" + stage)
      );

    // https://wiki.gentoo.org/wiki/Runit#Reboot_and_shutdown
    await alpine.sudoWriteExecutable(
      "/usr/local/sbin/rpoweroff",
      `#!/bin/sh
runit-init 0`
    );
    await alpine.sudoWriteExecutable(
      "/usr/local/sbin/rreboot",
      `#!/bin/sh
runit-init 6`
    );

    await alpine.addPackages(["runit", "eudev"]);

    const runit = new Runit({ alpine });

    await runit.addService(
      "getty-tty1",
      `#!/bin/sh
exec chpst -P getty 38400 tty1 linux`,
      false
    );
    await runit.addService(
      "getty-tty2",
      `#!/bin/sh
exec chpst -P getty 38400 tty2 linux`,
      false
    );
    await runit.addService(
      "getty-ttyS0",
      `#!/bin/sh
exec chpst -P getty 38400 ttyS0 linux`,
      false
    );

    return runit;
  }

  async addService(
    name: string,
    script: string,
    log: boolean = true
  ): Promise<void> {
    const runScriptPath = path.join("/etc/sv/", name, "/run");
    await this.alpine.sudoWriteExecutable(runScriptPath, script);
    if (log) {
      const logScriptPath = path.join("/etc/sv/", name, "/log/run");
      await this.alpine.sudoWriteExecutable(
        logScriptPath,
        `#!/bin/sh
exec logger -p daemon.info -t '${name}'`
      );
      await this.alpine.symlink(
        `/run/runit/supervise.${name}.log`,
        path.join("/etc/sv/", name, "/log/supervise")
      );
    }
    // Activar servicio
    await this.alpine.symlink(
      path.join("/etc/sv/", name),
      path.join("/etc/runit/runsvdir/default/", name)
    );
    await this.alpine.symlink(
      `/run/runit/supervise.${name}`,
      path.join("/etc/sv/", name, "/supervise")
    );
  }
}