#!/usr/bin/python3

"""

Execute commands on first-boot

Sequentially execute a list of commands on first-boot / instantiation.

This stage uses a logic similar to systemd's first-boot to execute a given

script only the first time the image is booted.

An empty flag file /etc/osbuild-first-boot is written to /etc and a systemd

service is enabled that is only run when the file exits, and will remove it

before executing the given commands.

If the flag-file cannot be removed, the service fails without executing

any further first-boot commands.

"""

import os

import sys

import osbuild.api

SCHEMA = """

"additionalProperties": false,

"required": ["commands"],

"properties": {

  "commands": {

    "type": "array",

    "description": "The command lines to execute",

    "items": {

      "type": "string"

    }

  },

  "wait_for_network": {

    "type": "boolean",

    "description": "Wait for the network to be up before executing",

    "default": false

  }

}

"""

def add_first_boot(tree, commands, wait_for_network):

    if wait_for_network:

        network = """Wants=network-online.target

After=network-online.target"""

    else:

        network = ""

    execs = "\n"

    for command in commands:

        execs += f"ExecStart={command}\n"

    service = f"""[Unit]

Description=OSBuild First Boot Service

ConditionPathExists=/etc/osbuild-first-boot

{network}

[Service]

Type=oneshot

{execs}"""

    os.makedirs(f"{tree}/usr/lib/systemd/system/default.target.wants", exist_ok=True)

    with open(f"{tree}/usr/lib/systemd/system/osbuild-first-boot.service", "w") as f:

        f.write(service)

    os.symlink("../osbuild-first-boot.service",

               f"{tree}/usr/lib/systemd/system/default.target.wants/osbuild-first-boot.service")

    os.makedirs(f"{tree}/etc", exist_ok=True)

    open(f"{tree}/etc/osbuild-first-boot", 'a').close()

def main(tree, options):

    commands = options["commands"]

    wait_for_network = options.get("wait_for_network", False)

    commands = ["/usr/bin/rm /etc/osbuild-first-boot"] + commands

    add_first_boot(tree, commands, wait_for_network)

    return 0

if __name__ == '__main__':

    args = osbuild.api.arguments()

    r = main(args["tree"], args["options"])

    sys.exit(r)