""" This is used to download and install apt packages and install them under the current user.
    This script is particularly useful for those who don't have sudo access."""

#!/usr/bin/python3.10.6

# we are disabling pylint checking some imports to save action minutes on github.
import subprocess
import os
import glob
import logging
import click  # pylint: disable=import-error


class LocalAptInstaller:
    """ This class is has all the functionality to download
        and install debian packages and add them to the PATH."""

    def __init__(self, apt_pkg, install_dir):
        self.apt_pkg_name = apt_pkg
        self.home_path = ""
        self.local_apps_folder_name = install_dir
        self.packages_list = [""]
        self.executables_list = [""]

    def download_package(self):
        """ This function uses apt-get to download our debian package locally."""
        logging.info("Downloading %s", self.apt_pkg_name)

        # We want to parse the package name here to get it's dependencies.
        # This allows us to pass in this string easier to subprocess.
        # Apparently this can download a package and all it's
        # dependancies = apt-get download $(apt-rdepends <package>|grep -v "^ ")
        package_parsed = f'$(apt-rdepends {self.apt_pkg_name}|grep -v "^ ")'

        # Need to navigate to the folder we want to install these packages too.
        # In our case its the user directory
        self.home_path = os.path.expanduser('~')
        os.chdir(self.home_path)

        # Then we want to make an local apps directory
        subprocess.call(
            ["mkdir", "-p", os.path.expanduser(f'~/{self.local_apps_folder_name}')])

        # Then we can go into that directory.
        os.chdir(f"{self.home_path}/{self.local_apps_folder_name}/")

        # And finally we can download our package and it's dependencies.
        cmd = subprocess.Popen(
            f'apt-get download {package_parsed}', shell=True)
        cmd.communicate()

    def install_deb_package(self):
        """ This function uses dpkg to install the package locally."""
        logging.info("Installing %s", self.apt_pkg_name)

        # first we need to get a list of all the packages and dependencies downloaded.
        self.packages_list = glob.glob(
            f"{self.home_path}/{self.local_apps_folder_name}/*.deb")

        # next we need to unpackage them.
        for package in self.packages_list:
            cmd = subprocess.Popen(
                f'dpkg -x {package} .', shell=True)
            cmd.communicate()

    def add_package_to_path(self):
        """ This function adds the package we've installed to PATH so it can be used."""
        logging.info("Adding %s to PATH", self.apt_pkg_name)

        # We need to get a list of executables from the packages
        # we've downloaded and the dependencies.
        executables = subprocess.check_output(
            "find . -type f -executable -print", stderr=subprocess.STDOUT,
            shell=True).decode("utf-8")

        # we need to get the executables into a list so they are manageable.
        self.executables_list = executables.splitlines()

        for idx, _ in enumerate(self.executables_list):
            # need to remove the file name and just point the path to the folder.
            executable_str = str(self.executables_list[idx]).rsplit('/', 1)[0]

            # we need to then concatenate the file executables together to the PATH variable
            self.executables_list[idx] = f"{self.local_apps_folder_name}/{executable_str[2:]}"

        # Now we need to open our .profile file
        with open(f"{self.home_path}/.profile", "a", encoding="utf8") as myfile:
            for idx, _ in enumerate(self.executables_list):
                # Then finally we can insert these into the
                # .profile file for these to be added to the PATH
                myfile.write(
                    f'\nexport PATH="$PATH:$HOME/{self.executables_list[idx]}"')


@click.command()
@click.option("--apt_pkg", default="cflow",
              help="The apt package you wish to download and install under the current user.")
@click.option("--install_dir", default="apps",
              help="You can give the name of the directroy you'd like to install the apps too.")
# pre-requisite run this once: sudo apt-get install apt-rdepends
def install_apt_pkg(apt_pkg, install_dir):
    """ This script is used download and dpkg apt packages
        locally if the user doesn't have sudo permissions """

    installer = LocalAptInstaller(apt_pkg, install_dir)
    try:
        installer.download_package()
        installer.install_deb_package()
        installer.add_package_to_path()
    except RuntimeError:
        logging.error("Install Failed!")


if __name__ == '__main__':
     # use this to log to a file.
     # logging.basicConfig(filename='example.log', encoding='utf-8', level=logging.INFO)
     # logging.basicConfig(level=logging.INFO) # use this to log to the terminal.
     install_apt_pkg()