local Players = game:GetService("Players")
local RunService = game:GetService("RunService")

local TARGET_GUN_NAME = "MatchGun"
local BEAM_THICKNESS = 0.1
local MAX_DIST = 500 
local ROTATION_OFFSET = CFrame.Angles(0, math.rad(90), 0) 

local function updateTracer(player)
    local character = player.Character
    if not character then return end

    local matchGun = character:FindFirstChild(TARGET_GUN_NAME, true)
    local barrel = nil
    
    if matchGun then
        local model = matchGun:FindFirstChild("Model")
        barrel = model and model:FindFirstChild("Barrel")
    end

    local tracerName = player.Name .. "_Tracer"
    local existingTracer = workspace:FindFirstChild(tracerName)

    if not barrel or not barrel:IsDescendantOf(workspace) then
        if existingTracer then
            existingTracer:Destroy()
        end
        return 
    end

    if not existingTracer then
        existingTracer = Instance.new("Part")
        existingTracer.Name = tracerName
        existingTracer.Material = Enum.Material.Neon
        existingTracer.CanCollide = false
        existingTracer.Anchored = true
        existingTracer.Parent = workspace
    end

    local shootFrame = barrel.CFrame * ROTATION_OFFSET
    local rayDir = shootFrame.LookVector * MAX_DIST
    
    local rayParams = RaycastParams.new()
    rayParams.FilterDescendantsInstances = {character, existingTracer} 
    rayParams.FilterType = Enum.RaycastFilterType.Exclude

    local result = workspace:Raycast(barrel.Position, rayDir, rayParams)
    
    local beamLen = MAX_DIST
    local hitColor = Color3.fromRGB(255, 0, 0)

    if result then
        beamLen = result.Distance
        local hitChar = result.Instance:FindFirstAncestorOfClass("Model")
        
        if hitChar and hitChar:FindFirstChild("Humanoid") then
            local hitPlayer = Players:GetPlayerFromCharacter(hitChar)
            if hitPlayer and hitPlayer ~= player then
                hitColor = Color3.fromRGB(255, 255, 0)
                
                local hum = hitChar:FindFirstChild("Humanoid")
                if hum then
                    hum.DisplayDistanceType = Enum.HumanoidDisplayDistanceType.None
                    hum.HealthDisplayType = Enum.HumanoidHealthDisplayType.AlwaysOff
                end
            end
        end
    end

    existingTracer.Size = Vector3.new(BEAM_THICKNESS, BEAM_THICKNESS, beamLen)
    existingTracer.Color = hitColor
    existingTracer.CFrame = shootFrame * CFrame.new(0, 0, -beamLen / 2)
end

RunService.RenderStepped:Connect(function()
    for _, player in ipairs(Players:GetPlayers()) do
        updateTracer(player)
        
        local char = player.Character
        if char then
            for _, p in ipairs(char:GetDescendants()) do
                if p:IsA("BasePart") or p:IsA("Decal") then
                    if p.Name == "HumanoidRootPart" then
                        p.Transparency = 1
                    else
                        p.Transparency = 0
                    end
                end
            end
        end
    end
end)