-- Smooth Fly GUI — camera-relative movement + auto shift-lock + fixed vertical speed
-- Place this LocalScript into StarterGui

local Players = game:GetService("Players")
local UIS = game:GetService("UserInputService")
local RS = game:GetService("RunService")
local Workspace = game:GetService("Workspace")

local player = Players.LocalPlayer
local PlayerGui = player:WaitForChild("PlayerGui")
local cam = Workspace.CurrentCamera

-- GUI ------------------------------------------------
local gui = Instance.new("ScreenGui")
gui.Name = "FlyGUI"
gui.ResetOnSpawn = false
gui.Parent = PlayerGui

local toggleBtn = Instance.new("ImageButton")
toggleBtn.Size = UDim2.new(0,64,0,64)
toggleBtn.Position = UDim2.new(0.04,0,0.78,0)
toggleBtn.BackgroundColor3 = Color3.fromRGB(98,72,255)
toggleBtn.Image = "rbxassetid://3926305904"
toggleBtn.ImageRectOffset = Vector2.new(364,324)
toggleBtn.ImageRectSize = Vector2.new(36,36)
toggleBtn.AutoButtonColor = true
toggleBtn.Active = true
toggleBtn.Draggable = true
toggleBtn.Parent = gui
Instance.new("UICorner", toggleBtn).CornerRadius = UDim.new(1,0)
do local s = Instance.new("UIStroke", toggleBtn); s.Thickness = 2; s.Color = Color3.fromRGB(255,255,255) end

local sliderFrame = Instance.new("Frame")
sliderFrame.Size = UDim2.new(0,180,0,44)
sliderFrame.Position = UDim2.new(0,74,0,-10)
sliderFrame.BackgroundColor3 = Color3.fromRGB(40,40,40)
sliderFrame.Visible = false
sliderFrame.Parent = toggleBtn
Instance.new("UICorner", sliderFrame).CornerRadius = UDim.new(0.5,0)

local bar = Instance.new("Frame")
bar.Size = UDim2.new(1,-26,0,10)
bar.Position = UDim2.new(0,13,0.4,-5)
bar.BackgroundColor3 = Color3.fromRGB(110,110,110)
bar.Parent = sliderFrame
Instance.new("UICorner", bar).CornerRadius = UDim.new(1,0)

local knob = Instance.new("Frame")
knob.Size = UDim2.new(0,18,0,18)
knob.Position = UDim2.new(0,0,0.4,-9)
knob.BackgroundColor3 = Color3.fromRGB(0,200,255)
knob.Parent = bar
Instance.new("UICorner", knob).CornerRadius = UDim.new(1,0)

local label = Instance.new("TextLabel")
label.Size = UDim2.new(1,0,0,16)
label.Position = UDim2.new(0,0,0,4)
label.BackgroundTransparency = 1
label.TextColor3 = Color3.fromRGB(255,255,255)
label.Font = Enum.Font.GothamBold
label.TextSize = 14
label.Text = "Speed: 2"
label.Parent = sliderFrame

local upBtn = Instance.new("TextButton")
upBtn.Size = UDim2.new(0,60,0,60)
upBtn.Position = UDim2.new(0.88,0,0.65,0)
upBtn.Text = "⬆️"
upBtn.Font = Enum.Font.GothamBold
upBtn.TextSize = 28
upBtn.TextColor3 = Color3.fromRGB(255,255,255)
upBtn.BackgroundColor3 = Color3.fromRGB(0,170,255)
upBtn.Visible = false
upBtn.Parent = gui
Instance.new("UICorner", upBtn).CornerRadius = UDim.new(1,0)

local downBtn = Instance.new("TextButton")
downBtn.Size = UDim2.new(0,60,0,60)
downBtn.Position = UDim2.new(0.88,0,0.78,0)
downBtn.Text = "⬇️"
downBtn.Font = Enum.Font.GothamBold
downBtn.TextSize = 28
downBtn.TextColor3 = Color3.fromRGB(255,255,255)
downBtn.BackgroundColor3 = Color3.fromRGB(255,80,80)
downBtn.Visible = false
downBtn.Parent = gui
Instance.new("UICorner", downBtn).CornerRadius = UDim.new(1,0)

-- Variables & defaults --------------------------------
local flying = false
local speedLevel = 1            -- 1..50 slider
local speedMultiplier = 2      -- each level adds 2 studs/sec (so level*2 studs/sec)
local speed = speedLevel * speedMultiplier
local verticalSpeed = 14       -- fixed vertical speed (up/down)
local humanoid, root, char
local BV, BG                   -- BodyVelocity & BodyGyro
local draggingKnob = false
local ascendMobile = false
local descendMobile = false
local shiftLockActive = false

-- Utility: get character references -------------------
local function getCharacter()
    char = player.Character or player.CharacterAdded:Wait()
    humanoid = char:WaitForChild("Humanoid")
    root = char:WaitForChild("HumanoidRootPart")
end

-- Stop any falling animation & ensure physics state ----
local function stopFallingAnimation()
    if not humanoid then return end
    for _, track in ipairs(humanoid:GetPlayingAnimationTracks()) do
        local n = track.Name or ""
        if n:lower():find("fall") or n:lower():find("jump") then
            pcall(function() track:Stop() end)
        end
    end
    pcall(function() humanoid:ChangeState(Enum.HumanoidStateType.Physics) end)
end

-- Shift-lock emulation: rotate character to face camera forward
local function enableShiftLock()
    shiftLockActive = true
end
local function disableShiftLock()
    shiftLockActive = false
end

-- Start / stop flying ---------------------------------
local function startFly()
    getCharacter()
    stopFallingAnimation()

    -- Create BodyVelocity
    BV = Instance.new("BodyVelocity")
    BV.Name = "FlyBV"
    BV.MaxForce = Vector3.new(1e5,1e5,1e5)
    BV.P = 1700
    BV.Velocity = Vector3.zero
    BV.Parent = root

    -- Create BodyGyro
    BG = Instance.new("BodyGyro")
    BG.Name = "FlyBG"
    BG.MaxTorque = Vector3.new(4e5,4e5,4e5)
    BG.P = 4500
    BG.D = 200
    BG.CFrame = root.CFrame
    BG.Parent = root

    humanoid.AutoRotate = false

    upBtn.Visible = true
    downBtn.Visible = true

    enableShiftLock()
end

local function stopFly()
    if BV and BV.Parent then BV:Destroy() end
    if BG and BG.Parent then BG:Destroy() end
    if humanoid then
        humanoid.AutoRotate = true
        pcall(function() humanoid:ChangeState(Enum.HumanoidStateType.GettingUp) end)
    end

    upBtn.Visible = false
    downBtn.Visible = false

    disableShiftLock()
end

-- Toggle button --------------------------------------
toggleBtn.MouseButton1Click:Connect(function()
    flying = not flying
    sliderFrame.Visible = flying
    if flying then
        toggleBtn.BackgroundColor3 = Color3.fromRGB(0,200,100)
        pcall(startFly)
    else
        toggleBtn.BackgroundColor3 = Color3.fromRGB(98,72,255)
        pcall(stopFly)
    end
end)

-- Slider handling ------------------------------------
bar.InputBegan:Connect(function(input)
    if input.UserInputType == Enum.UserInputType.MouseButton1 or input.UserInputType == Enum.UserInputType.Touch then
        draggingKnob = true
    end
end)
UIS.InputChanged:Connect(function(input)
    if not draggingKnob then return end
    if input.UserInputType ~= Enum.UserInputType.MouseMovement and input.UserInputType ~= Enum.UserInputType.Touch then return end
    local rel = math.clamp((input.Position.X - bar.AbsolutePosition.X) / bar.AbsoluteSize.X, 0, 1)
    knob.Position = UDim2.new(rel, -9, 0.4, -9)
    speedLevel = math.max(1, math.floor(rel * 49) + 1)
    speed = speedLevel * speedMultiplier
    label.Text = "Speed: " .. tostring(speed)
end)
UIS.InputEnded:Connect(function(input)
    if input.UserInputType == Enum.UserInputType.MouseButton1 or input.UserInputType == Enum.UserInputType.Touch then
        draggingKnob = false
    end
end)

-- Mobile up/down buttons --------------------------------
upBtn.MouseButton1Down:Connect(function() ascendMobile = true end)
upBtn.MouseButton1Up:Connect(function() ascendMobile = false end)
downBtn.MouseButton1Down:Connect(function() descendMobile = true end)
downBtn.MouseButton1Up:Connect(function() descendMobile = false end)

-- Main flight loop ------------------------------------
RS.RenderStepped:Connect(function(dt)
    if not flying then return end
    if not humanoid or not root or not BV or not BG then return end

    -- 1) compute camera basis (flat)
    local camCF = cam.CFrame
    local camForward = Vector3.new(camCF.LookVector.X, 0, camCF.LookVector.Z)
    if camForward.Magnitude < 0.001 then camForward = Vector3.new(0,0,-1) end
    camForward = camForward.Unit
    local camRight = Vector3.new(camCF.RightVector.X, 0, camCF.RightVector.Z)
    if camRight.Magnitude < 0.001 then camRight = Vector3.new(1,0,0) end
    camRight = camRight.Unit

    -- 2) gather player input:
    -- keyboard check (prefer keyboard if pressed)
    local kbX = 0; local kbZ = 0
    if UIS:IsKeyDown(Enum.KeyCode.D) or UIS:IsKeyDown(Enum.KeyCode.Right) then kbX = kbX + 1 end
    if UIS:IsKeyDown(Enum.KeyCode.A) or UIS:IsKeyDown(Enum.KeyCode.Left) then kbX = kbX - 1 end
    if UIS:IsKeyDown(Enum.KeyCode.W) or UIS:IsKeyDown(Enum.KeyCode.Up) then kbZ = kbZ + 1 end
    if UIS:IsKeyDown(Enum.KeyCode.S) or UIS:IsKeyDown(Enum.KeyCode.Down) then kbZ = kbZ - 1 end

    local inputX, inputZ = 0, 0

    if math.abs(kbX) > 0.001 or math.abs(kbZ) > 0.001 then
        inputX = kbX
        inputZ = kbZ
        -- normalize diagonal movement
        local mag = math.sqrt(inputX*inputX + inputZ*inputZ)
        if mag > 1 then inputX = inputX / mag; inputZ = inputZ / mag end
    else
        -- fallback to Humanoid.MoveDirection for joystick/mobile
        local md = humanoid.MoveDirection or Vector3.new(0,0,0)
        -- convert md into camera-relative components by dotting with camera basis
        inputX = md:Dot(camRight)
        inputZ = md:Dot(camForward)
        -- if tiny, zero them
        if math.abs(inputX) < 0.001 then inputX = 0 end
        if math.abs(inputZ) < 0.001 then inputZ = 0 end
        -- normalize
        local mag = math.sqrt(inputX*inputX + inputZ*inputZ)
        if mag > 1 then inputX = inputX / mag; inputZ = inputZ / mag end
    end

    -- 3) build horizontal move vector (camera-relative)
    local moveVec = (camForward * inputZ) + (camRight * inputX)

    -- 4) vertical control: fixed 14 studs/sec (keyboard or mobile buttons)
    local ascend = UIS:IsKeyDown(Enum.KeyCode.Space) or ascendMobile
    local descend = UIS:IsKeyDown(Enum.KeyCode.LeftControl) or UIS:IsKeyDown(Enum.KeyCode.LeftShift) or descendMobile

    local yVel = 0
    if ascend then
        yVel = verticalSpeed
    elseif descend then
        yVel = -verticalSpeed
    end

    -- 5) target velocity (horizontal uses speed slider, vertical is fixed)
    local horizVel = Vector3.new(0,0,0)
    if moveVec.Magnitude > 0.001 then
        horizVel = moveVec.Unit * speed
    end
    local target = Vector3.new(horizVel.X, yVel, horizVel.Z)

    -- 6) smooth the velocity
    BV.Velocity = BV.Velocity:Lerp(target, math.clamp(12 * dt, 0, 1))

    -- 7) rotation: emulate shift-lock while flying (face camera forward horizontally)
    if shiftLockActive then
        local look = Vector3.new(camForward.X, 0, camForward.Z)
        if look.Magnitude > 0.001 then
            local targetC = CFrame.new(root.Position, root.Position + look.Unit)
            -- smooth gyro so it doesn't snap
            local smooth = math.clamp(10 * dt, 0, 1)
            BG.CFrame = root.CFrame:Lerp(targetC, smooth)
        end
    else
        -- otherwise, if moving, face move direction
        if moveVec.Magnitude > 0.001 then
            local targetC = CFrame.new(root.Position, root.Position + moveVec.Unit)
            BG.CFrame = root.CFrame:Lerp(targetC, math.clamp(10 * dt, 0, 1))
        end
    end
end)

-- cleanup/respawn handling ----------------------------
player.CharacterAdded:Connect(function()
    flying = false
    pcall(stopFly)
    sliderFrame.Visible = false
    toggleBtn.BackgroundColor3 = Color3.fromRGB(98,72,255)
end)

-- finished