using { /Fortnite.com/Devices }
using { /Fortnite.com/Characters }
using { /Verse.org/Simulation }
using { /Verse.org/SpatialMath }
using { /UnrealEngine.com/Temporary/Diagnostics }

# MOVE THAT CHARACTER — push the player's body around from Verse.
#
# Once you hold a player's fort_character you can move it two clean ways:
#   * SetLinearVelocity — DIRECT. Set how fast and which way they're moving
#                   right now (meters/second). The launch-pad punch.
#   * ApplyLinearImpulse — PHYSICS. A one-off shove in Newton-seconds, blended
#                   with whatever they were already doing — a softer nudge.
# (A third, TeleportTo, blinks them instantly to a spot — we use it in the
# capstone, where it pairs with the kill-floor catcher.)
#
# This device wires a Button to a "launch" that flings every player straight
# up — a crowd-pleaser bounce pad you can drop into any island.
#
# AXIS NAMING: a /Verse.org/SpatialMath vector3 uses Forward / Left / Up
# (the same Scene Graph convention you met in the Animation series) — NOT
# X / Y / Z. Up is the vertical axis, so an upward pop sets only `Up`.
char_launcher_device := class(creative_device):

    # Press this to launch everyone.
    @editable
    LaunchButton : button_device = button_device{}

    # Upward launch speed in meters/second. Designer-tunable.
    @editable
    LaunchSpeed : float = 15.0

    OnBegin<override>()<suspends> : void =
        LaunchButton.InteractedWithEvent.Subscribe(OnLaunch)

    OnLaunch(Presser : agent) : void =
        Playspace := GetPlayspace()
        # Loop bodies of every player who currently HAS a character. The
        # `Body := P.GetFortCharacter[]` in the for-clause both fetches and
        # filters: players mid-respawn (no body) are simply skipped.
        for (P : Playspace.GetPlayers(), Body := P.GetFortCharacter[]):
            # Set an upward velocity. Forward/Left stay 0 so it's a clean pop.
            Up := vector3{ Forward := 0.0, Left := 0.0, Up := LaunchSpeed }
            Body.SetLinearVelocity(Up)
            Print("Launched a player upward at {LaunchSpeed} m/s")

    # A gentler alternative: a physics shove instead of a hard velocity set.
    # ApplyLinearImpulse adds to current motion rather than replacing it, so a
    # running player keeps their forward momentum and just gets bumped upward.
    Nudge(Body : fort_character, Strength : float) : void =
        Push := vector3{ Forward := 0.0, Left := 0.0, Up := Strength }
        Body.ApplyLinearImpulse(Push)