import os

from launch_ros.actions import Node
from ament_index_python.packages import get_package_share_directory
from launch import LaunchDescription
from launch.actions import IncludeLaunchDescription
from launch.launch_description_sources import PythonLaunchDescriptionSource
from launch.actions import DeclareLaunchArgument
from launch.substitutions import LaunchConfiguration

def generate_launch_description():
    # Package Paths
    nav2_bringup_dir = get_package_share_directory('nav2_bringup')

    # Launch Arguments
    use_sim_time = LaunchConfiguration('use_sim_time', default='true')
    params_file = LaunchConfiguration('params_file', default=os.path.join(
        NAME_OF_YOUR_PKG, 'params', 'nav2_params.yaml'))

    return LaunchDescription([
        DeclareLaunchArgument(
            'use_sim_time',
            default_value='true',
            description='Use simulation clock if true'),

        DeclareLaunchArgument(
            'params_file',
            default_value=params_file,
            description='Full path to param file to load'),
        

        IncludeLaunchDescription(
            PythonLaunchDescriptionSource(
                os.path.join(nav2_bringup_dir, 'launch', 'navigation_launch.py')
            ),
            launch_arguments={
                'use_sim_time': use_sim_time,
                'params_file': params_file,
                'autostart': 'false'
            }.items(),
        ),

        Node(
            package='NAME_OF_YOUR_PKG',
            executable='follow_route',
            name='follow_route',
            parameters=[{
                'use_sim_time': True
            }],
            output='screen'
        ),
    ])