# This is a Verse Script. Think of it as the "Brain" of the device.
# It listens for events and changes things in the world.

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

# We define a "Device" that holds our Player Reference and Text Display.
# This is like creating a custom object in the game.
kill_counter_device := class(creative_device):

    # These are the "Components" or parts of our device.
    # Imagine these are the wires connecting things together.
    # Wire these up in the UEFN editor by selecting the device and
    # dragging the matching device into each slot.
    @editable
    MyTextDisplay : text_display_device = text_display_device{}

    # This is a "Variable".
    # In game terms: A variable is like a scoreboard that changes.
    # Here, we store the player's current elimination count.
    var CurrentScore : int = 0

    # This function runs when the island starts.
    OnBegin<override>()<suspends> : void =
    {
        # Get the playspace so we can access all players and their events.
        Playspace := GetPlayspace()

        # Listen for every player who joins the session.
        # When they join, we subscribe to their elimination event.
        Playspace.PlayerAddedEvent().Subscribe(OnPlayerAdded)

        # Also subscribe for players already in the session at start.
        for (Player : Playspace.GetPlayers()):
            OnPlayerAdded(Player)
    }

    # Called whenever a new player is added to the session.
    OnPlayerAdded(Player : player) : void =
    {
        # Cast the player to a fort_character so we can access
        # game-specific events like EliminatedEvent.
        if (FortCharacter := Player.GetFortCharacter[]):
            # Subscribe to this character's EliminatedEvent.
            # It fires whenever THIS player is eliminated by someone else.
            FortCharacter.EliminatedEvent().Subscribe(OnCharacterEliminated)
    }

    # This function runs EVERY TIME a character is eliminated.
    # "Event" = A moment in time that something happens (like a bomb exploding).
    # The EliminatedEvent gives us an elimination_result payload.
    OnCharacterEliminated(Result : elimination_result) : void =
    {
        # The eliminator is the player who got the kill.
        # Result.Eliminator is of type ?agent, so we check it with 'if'.
        if (EliminatorAgent := Result.Eliminator?):
            # Cast agent -> player so we can query Fortnite-specific stats.
            if (EliminatorPlayer := player[EliminatorAgent]):
                # 1. Get the eliminator's current score from the playspace.
                #    GetPlayspace().GetPlayerStats() is the real API for
                #    reading per-player stat values set up in the experience.
                # note: There is no bare GetEliminations() method on player.
                #       Increment our own counter instead, which is the
                #       standard pattern for custom kill-count tracking.
                set CurrentScore += 1

                # 2. Update the Text Display.
                # We convert the number to text (e.g., 5 -> "5") and show it.
                MyTextDisplay.SetText(StringToMessage($"Eliminations: {CurrentScore}"))

    # Helper to convert a string interpolation to the message type
    # required by text_display_device.SetText().
    StringToMessage(S : string) : message =
    {
        # note: text_display_device.SetText() accepts a message value.
        #       The easiest real way to build one is a localizable string
        #       literal; here we use the string directly via HudMessageFromString.
        return HudMessageFromString(S)
    }