using { /Verse.org/SceneGraph }
using { /Verse.org/SceneGraph/KeyframedMovement }
using { /Verse.org/Simulation }
using { /Verse.org/SpatialMath }

# Bolt this onto any entity that ALSO has a Keyframed Movement component
# (add one in the editor: Add Component -> Keyframed Movement). When the
# game begins, this glides the entity GlideDistance units forward, smoothly.
glide_to_target_component := class<final_super>(component):

    # How far forward to glide, in units. A knob you can tune in the editor.
    @editable
    var GlideDistance<public>:float = 500.0

    # How long the glide should take, in seconds.
    @editable
    var GlideSeconds<public>:float = 3.0

    OnBeginSimulation<override>():void =
        # Be polite: let the base class do its own startup first.
        (super:)OnBeginSimulation()

        # Find the mover sitting on this same entity. Square brackets because
        # it can fail — if nobody added a Keyframed Movement component, there's
        # nothing to drive, so we just stop.
        if (Mover := Entity.GetComponent[keyframed_movement_component]):
            # Describe ONE keyframe: "move GlideDistance forward, taking
            # GlideSeconds, easing in and out so it starts and stops gently."
            # Translation is relative to where the entity is right now.
            Step := keyframed_movement_delta:
                Duration := GlideSeconds
                Easing := ease_in_out_cubic_bezier_easing_function{}
                Transform := transform:
                    Translation := vector3:
                        Forward := GlideDistance
                        Left := 0.0
                        Up := 0.0

            # Hand the keyframe list to the mover and tell it to play once.
            Mover.SetKeyframes(array{Step}, oneshot_keyframed_movement_playback_mode{})
            Mover.Play()