using UnityEngine;
#if ENABLE_INPUT_SYSTEM
using UnityEngine.InputSystem;
#endif

/// <summary>
/// Shared low-level input reads used by the camera rigs, the paint controller and the modes. Each
/// method preserves its original per-backend behaviour (new Input System when present, legacy Input
/// Manager otherwise). Sensitivity scaling stays at the call sites.
/// </summary>
public static class InputUtil
{
    /// <summary>Raw mouse delta this frame (pixels); the legacy path scales GetAxisRaw by 10 to match.</summary>
    public static Vector2 ReadMouseDelta()
    {
#if ENABLE_INPUT_SYSTEM
        return Mouse.current != null ? Mouse.current.delta.ReadValue() : Vector2.zero;
#else
        return new Vector2(Input.GetAxisRaw("Mouse X"), Input.GetAxisRaw("Mouse Y")) * 10f;
#endif
    }

    /// <summary>Raw mouse-wheel delta this frame (usually only its sign is used).</summary>
    public static float ReadScroll()
    {
#if ENABLE_INPUT_SYSTEM
        if (Mouse.current != null) return Mouse.current.scroll.ReadValue().y;
#endif
#if ENABLE_LEGACY_INPUT_MANAGER
        return Input.GetAxis("Mouse ScrollWheel");
#else
        return 0f;
#endif
    }

    /// <summary>Locks+hides or frees+shows the hardware cursor.</summary>
    public static void SetCursorLocked(bool locked)
    {
        Cursor.lockState = locked ? CursorLockMode.Locked : CursorLockMode.None;
        Cursor.visible = !locked;
    }

    public static bool ShiftHeld()
    {
#if ENABLE_INPUT_SYSTEM
        var kb = Keyboard.current;
        if (kb != null) return kb.leftShiftKey.isPressed || kb.rightShiftKey.isPressed;
#endif
#if ENABLE_LEGACY_INPUT_MANAGER
        return Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift);
#else
        return false;
#endif
    }

    public static bool CtrlHeld()
    {
#if ENABLE_INPUT_SYSTEM
        var kb = Keyboard.current;
        if (kb != null) return kb.leftCtrlKey.isPressed || kb.rightCtrlKey.isPressed;
#endif
#if ENABLE_LEGACY_INPUT_MANAGER
        return Input.GetKey(KeyCode.LeftControl) || Input.GetKey(KeyCode.RightControl);
#else
        return false;
#endif
    }

    public static bool LeftMouseHeld()
    {
#if ENABLE_INPUT_SYSTEM
        return Mouse.current != null && Mouse.current.leftButton.isPressed;
#else
        return Input.GetMouseButton(0);
#endif
    }

    public static bool RightMouseHeld()
    {
#if ENABLE_INPUT_SYSTEM
        return Mouse.current != null && Mouse.current.rightButton.isPressed;
#else
        return Input.GetMouseButton(1);
#endif
    }

    public static bool MiddleMouseHeld()
    {
#if ENABLE_INPUT_SYSTEM
        return Mouse.current != null && Mouse.current.middleButton.isPressed;
#else
        return Input.GetMouseButton(2);
#endif
    }

    /// <summary>Left mouse button pressed on this exact frame (edge, not held).</summary>
    public static bool LeftClickedThisFrame()
    {
#if ENABLE_INPUT_SYSTEM
        return Mouse.current != null && Mouse.current.leftButton.wasPressedThisFrame;
#else
        return Input.GetMouseButtonDown(0);
#endif
    }

    /// <summary>Key pressed on this exact frame (edge), regardless of UI focus. The parameter type
    /// follows the active input backend, matching how the callers' serialized key fields are declared.</summary>
#if ENABLE_INPUT_SYSTEM
    public static bool KeyPressedThisFrame(Key key)
        => Keyboard.current != null && Keyboard.current[key].wasPressedThisFrame;
#else
    public static bool KeyPressedThisFrame(KeyCode key) => Input.GetKeyDown(key);
#endif

    /// <summary>Gameplay key pressed on this exact frame (edge), suppressed while a UI text field is
    /// focused so typing never triggers gameplay bindings.</summary>
#if ENABLE_INPUT_SYSTEM
    public static bool GameplayKeyPressed(Key key) => !TypingGuard.IsTyping && KeyPressedThisFrame(key);
#else
    public static bool GameplayKeyPressed(KeyCode key) => !TypingGuard.IsTyping && KeyPressedThisFrame(key);
#endif
}