#!/usr/bin/python3
# vim: tabstop=4 softtabstop=4 shiftwidth=4 expandtab


import sys
import os
import subprocess
import json
import jinja2


SETTINGS_PATH = "settings.json"
SYSTEMD_TEMPLATE = "systemd/webtemplate.service.jinja2"
FLASK_TEMPLATE = "flask/main.py.jinja2"
REPOSITORY_WEBROOT = "webroot"


def read_settings():
    """Read the SETTINGS_PATH File and return a Dictionary with its Content"""

    with open(SETTINGS_PATH, "r") as settings:
        settings = settings.read()

    settings = json.loads(settings)
    return settings


def build_systemd_file(settings):
    """Generate Systemd Unit File with Settings from SETTINGS_PATH"""

    with open(SYSTEMD_TEMPLATE, "r") as template:
        template = template.read()

    template = jinja2.Template(template)
    systemd_file = template.render(settings)

    subprocess.call("mkdir -p systemd/build", shell=True)
    file_path = "systemd/build/{}.service".format(settings["project_name"])

    with open(file_path, "w") as _file:
        _file.write(systemd_file)


def build_flask(settings):
    """Generate Python Flask File with Settings from SETTINGS_PATH"""

    with open(FLASK_TEMPLATE, "r") as template:
        template = template.read()
    
    template = jinja2.Template(template)
    flask_file = template.render(settings)

    subprocess.call("mkdir -p flask/build", shell=True)

    file_path = "flask/build/{}".format(settings["project_name"])
    
    with open(file_path, "w") as _file:
        _file.write(flask_file)


def install_webroot(settings):
    """Install every File from the Repositories Webroot to the Systems Webroot"""

    for directory, subdirs, files in os.walk(REPOSITORY_WEBROOT, topdown=False):
        for _file in files:
            path_to_file = os.path.join(directory, _file)
            relative_path = os.path.relpath(path_to_file, REPOSITORY_WEBROOT)
            target_path = os.path.join(settings["webroot"], relative_path)
            subprocess.run("install -Dm 644 {} {}".format(path_to_file, target_path), shell=True)


def uninstall_webroot(settings):
    """Uninstalls every File from the Systems Webroot"""

    path_to_delete = os.path.join(settings["webroot"], "*")
    subprocess.run("rm -rf {}".format(path_to_delete), shell=True)


def install_flask(settings):
    """Install the Executable for the Dynamic Web Server"""

    subprocess.call("sudo mkdir -p /opt/{}".format(settings["project_name"]), shell=True)
    subprocess.call("sudo install -Dm 744 flask/build/{0} /opt/{0}/{0}".format(settings["project_name"]), shell=True)
    order = "sudo find /opt/{0} -exec chown -R {1}:{2}".format(
        settings["project_name"],
        settings["user"],
        settings["group"]
    )
    order += " {} \;"
    subprocess.call(order, shell=True)


def uninstall_flask(settings):
    """Uninstall the Executable for the Dynamic Web Server"""

    subprocess.call("sudo rm -rf /opt/{}".format(settings["project_name"]), shell=True)


def install_systemd_file(settings):
    """Install the Systemd Unit for launching the dynamic Web Server"""

    subprocess.call("sudo install -Dm 644 systemd/build/{0}.service /etc/systemd/system/{0}.service".format(settings["project_name"]), shell=True)
    subprocess.call("sudo systemctl daemon-reload", shell=True)


def uninstall_systemd_file(settings):
    """Uninstall the Systemd Unit for launching the dynamic Web Server"""

    subprocess.call("sudo rm /etc/systemd/system/{0}.service".format(settings["project_name"]), shell=True)


def main():
    """The main Function"""

    settings = read_settings()  # get settings from SETTINGS_PATH

    # just one argument is allowed:
    if len(sys.argv) != 2:
        print("Provide exactly one parameter")
        sys.exit(1)

    # execute given command
    command = sys.argv[1]
    if command == "build_systemd_file":
        build_systemd_file(settings)
    elif command == "build_framework":
        if settings["framework"] == "flask":
            build_flask(settings)
        elif settings["framework"] == "actix-web":
            print("actix-web is not yet implemented ...")
            sys.exit(1)
        elif settings["framework"] == None:
            pass
        else:
            print("Unknown web framework selected")
            sys.exit(1)
    elif command == "install_webroot":
        install_webroot(settings)
    elif command == "uninstall_webroot":
        uninstall_webroot(settings)
    elif command == "install_framework":
        if settings["framework"] == "flask":
            install_flask(settings)
        elif settings["framework"] == "actix-web":
            print("actix-web is not yet implemented ...")
            sys.exit(1)
        elif settings["framework"] == None:
            pass
        else:
            print("Unknown web framework selected")
            sys.exit(1)
    elif command == "uninstall_framework":
        if settings["framework"] == "flask":
            uninstall_flask(settings)
        elif settings["framework"] == "actix-web":
            print("actix-web is not yet implemented ...")
            sys.exit(1)
        elif settings["framework"] == None:
            pass
        else:
            print("Unknown web framework selected")
            sys.exit(1)
    elif command == "install_systemd_file":
        install_systemd_file(settings)
    elif command == "uninstall_systemd_file":
        uninstall_systemd_file(settings)
    else:
        print("Unknown command")
        sys.exit(1)


if __name__ == "__main__":
    main()