import os

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


def generate_launch_description():
    use_sim_time = LaunchConfiguration("use_sim_time")
    slam_params_file = LaunchConfiguration("slam_params_file")

    remappings = [
        ("/map", "map"),
        ("/scan", "scan"),
        ("/tf", "tf"),
        ("/tf_static", "tf_static"),
    ]

    declare_use_sim_time_argument = DeclareLaunchArgument(
        "use_sim_time", default_value="true", description="Use simulation/Gazebo clock"
    )
    declare_slam_params_file_cmd = DeclareLaunchArgument(
        "slam_params_file",
        default_value=os.path.join(
            get_package_share_directory("slam_toolbox"),
            "config",
            "mapper_params_online_sync.yaml",
        ),
        description="Full path to the ROS2 parameters file to use for the slam_toolbox node",
    )

    start_sync_slam_toolbox_node = Node(
        parameters=[slam_params_file, {"use_sim_time": use_sim_time}],
        package="slam_toolbox",
        executable="sync_slam_toolbox_node",
        name="slam_toolbox",
        output="screen",
        remappings=remappings,
    )

    ld = LaunchDescription()

    ld.add_action(declare_use_sim_time_argument)
    ld.add_action(declare_slam_params_file_cmd)
    ld.add_action(start_sync_slam_toolbox_node)

    return ld