using System;
using UnityEngine.Events;
using UnityEngine.EventSystems;

namespace UnityEngine.UI
{
	[SelectionBase]
	[ExecuteInEditMode]
	[DisallowMultipleComponent]
	[RequireComponent(typeof(RectTransform))]
	public class uGUIScrollRect : UIBehaviour, IInitializePotentialDragHandler, IBeginDragHandler, IEndDragHandler, IDragHandler, IScrollHandler, ICanvasElement, ILayoutElement, ILayoutGroup, IEventSystemHandler, ILayoutController
	{
		protected uGUIScrollRect()
		{
		}

		public RectTransform content
		{
			get
			{
				return this.m_Content;
			}
			set
			{
				this.m_Content = value;
			}
		}

		public bool horizontal
		{
			get
			{
				return this.m_Horizontal;
			}
			set
			{
				this.m_Horizontal = value;
			}
		}

		public bool vertical
		{
			get
			{
				return this.m_Vertical;
			}
			set
			{
				this.m_Vertical = value;
			}
		}

		public uGUIScrollRect.MovementType movementType
		{
			get
			{
				return this.m_MovementType;
			}
			set
			{
				this.m_MovementType = value;
			}
		}

		public float elasticity
		{
			get
			{
				return this.m_Elasticity;
			}
			set
			{
				this.m_Elasticity = value;
			}
		}

		public bool inertia
		{
			get
			{
				return this.m_Inertia;
			}
			set
			{
				this.m_Inertia = value;
			}
		}

		public float decelerationRate
		{
			get
			{
				return this.m_DecelerationRate;
			}
			set
			{
				this.m_DecelerationRate = value;
			}
		}

		public float scrollSensitivity
		{
			get
			{
				return this.m_ScrollSensitivity;
			}
			set
			{
				this.m_ScrollSensitivity = value;
			}
		}

		public RectTransform viewport
		{
			get
			{
				return this.m_Viewport;
			}
			set
			{
				this.m_Viewport = value;
				this.SetDirtyCaching();
			}
		}

		public Slider horizontalSlider
		{
			get
			{
				return this.m_HorizontalSlider;
			}
			set
			{
				if (this.m_HorizontalSlider)
				{
					this.m_HorizontalSlider.onValueChanged.RemoveListener(new UnityAction<float>(this.SetHorizontalNormalizedPosition));
				}
				this.m_HorizontalSlider = value;
				if (this.m_HorizontalSlider)
				{
					this.m_HorizontalSlider.onValueChanged.AddListener(new UnityAction<float>(this.SetHorizontalNormalizedPosition));
				}
				this.SetDirtyCaching();
			}
		}

		public Slider verticalSlider
		{
			get
			{
				return this.m_VerticalSlider;
			}
			set
			{
				if (this.m_VerticalSlider)
				{
					this.m_VerticalSlider.onValueChanged.RemoveListener(new UnityAction<float>(this.SetVerticalNormalizedPosition));
				}
				this.m_VerticalSlider = value;
				if (this.m_VerticalSlider)
				{
					this.m_VerticalSlider.onValueChanged.AddListener(new UnityAction<float>(this.SetVerticalNormalizedPosition));
				}
				this.SetDirtyCaching();
			}
		}

		public uGUIScrollRect.SliderVisibility horizontalSliderVisibility
		{
			get
			{
				return this.m_HorizontalSliderVisibility;
			}
			set
			{
				this.m_HorizontalSliderVisibility = value;
				this.SetDirtyCaching();
			}
		}

		public uGUIScrollRect.SliderVisibility verticalSliderVisibility
		{
			get
			{
				return this.m_VerticalSliderVisibility;
			}
			set
			{
				this.m_VerticalSliderVisibility = value;
				this.SetDirtyCaching();
			}
		}

		public float horizontalSliderSpacing
		{
			get
			{
				return this.m_HorizontalSliderSpacing;
			}
			set
			{
				this.m_HorizontalSliderSpacing = value;
				this.SetDirty();
			}
		}

		public float verticalSliderSpacing
		{
			get
			{
				return this.m_VerticalSliderSpacing;
			}
			set
			{
				this.m_VerticalSliderSpacing = value;
				this.SetDirty();
			}
		}

		public uGUIScrollRect.ScrollRectEvent onValueChanged
		{
			get
			{
				return this.m_OnValueChanged;
			}
			set
			{
				this.m_OnValueChanged = value;
			}
		}

		protected RectTransform viewRect
		{
			get
			{
				if (this.m_ViewRect == null)
				{
					this.m_ViewRect = this.m_Viewport;
				}
				if (this.m_ViewRect == null)
				{
					this.m_ViewRect = (RectTransform)base.transform;
				}
				return this.m_ViewRect;
			}
		}

		public Vector2 velocity
		{
			get
			{
				return this.m_Velocity;
			}
			set
			{
				this.m_Velocity = value;
			}
		}

		private RectTransform rectTransform
		{
			get
			{
				if (this.m_Rect == null)
				{
					this.m_Rect = base.GetComponent<RectTransform>();
				}
				return this.m_Rect;
			}
		}

		public virtual void Rebuild(CanvasUpdate executing)
		{
			if (executing == CanvasUpdate.Prelayout)
			{
				this.UpdateCachedData();
			}
			if (executing == CanvasUpdate.PostLayout)
			{
				this.UpdateBounds();
				this.UpdateSliders(Vector2.zero);
				this.UpdatePrevData();
				this.m_HasRebuiltLayout = true;
			}
		}

		public virtual void LayoutComplete()
		{
		}

		public virtual void GraphicUpdateComplete()
		{
		}

		private void UpdateCachedData()
		{
			Transform transform = base.transform;
			this.m_HorizontalSliderRect = ((!(this.m_HorizontalSlider == null)) ? (this.m_HorizontalSlider.transform as RectTransform) : null);
			this.m_VerticalSliderRect = ((!(this.m_VerticalSlider == null)) ? (this.m_VerticalSlider.transform as RectTransform) : null);
			bool flag = this.viewRect.parent == transform;
			bool flag2 = !this.m_HorizontalSliderRect || this.m_HorizontalSliderRect.parent == transform;
			bool flag3 = !this.m_VerticalSliderRect || this.m_VerticalSliderRect.parent == transform;
			bool flag4 = flag && flag2 && flag3;
			this.m_HSliderExpand = (flag4 && this.m_HorizontalSliderRect && this.horizontalSliderVisibility == uGUIScrollRect.SliderVisibility.AutoHideAndExpandViewport);
			this.m_VSliderExpand = (flag4 && this.m_VerticalSliderRect && this.verticalSliderVisibility == uGUIScrollRect.SliderVisibility.AutoHideAndExpandViewport);
			this.m_HSliderHeight = ((!(this.m_HorizontalSliderRect == null)) ? this.m_HorizontalSliderRect.rect.height : 0f);
			this.m_VSliderWidth = ((!(this.m_VerticalSliderRect == null)) ? this.m_VerticalSliderRect.rect.width : 0f);
		}

		protected override void OnEnable()
		{
			base.OnEnable();
			if (this.m_HorizontalSlider)
			{
				this.m_HorizontalSlider.onValueChanged.AddListener(new UnityAction<float>(this.SetHorizontalNormalizedPosition));
			}
			if (this.m_VerticalSlider)
			{
				this.m_VerticalSlider.onValueChanged.AddListener(new UnityAction<float>(this.SetVerticalNormalizedPosition));
			}
			CanvasUpdateRegistry.RegisterCanvasElementForLayoutRebuild(this);
		}

		protected override void OnDisable()
		{
			CanvasUpdateRegistry.UnRegisterCanvasElementForRebuild(this);
			if (this.m_HorizontalSlider)
			{
				this.m_HorizontalSlider.onValueChanged.RemoveListener(new UnityAction<float>(this.SetHorizontalNormalizedPosition));
			}
			if (this.m_VerticalSlider)
			{
				this.m_VerticalSlider.onValueChanged.RemoveListener(new UnityAction<float>(this.SetVerticalNormalizedPosition));
			}
			this.m_HasRebuiltLayout = false;
			this.m_Tracker.Clear();
			this.m_Velocity = Vector2.zero;
			LayoutRebuilder.MarkLayoutForRebuild(this.rectTransform);
			base.OnDisable();
		}

		public override bool IsActive()
		{
			return base.IsActive() && this.m_Content != null;
		}

		private void EnsureLayoutHasRebuilt()
		{
			if (!this.m_HasRebuiltLayout && !CanvasUpdateRegistry.IsRebuildingLayout())
			{
				Canvas.ForceUpdateCanvases();
			}
		}

		public virtual void StopMovement()
		{
			this.m_Velocity = Vector2.zero;
		}

		public virtual void OnScroll(PointerEventData data)
		{
			if (!this.IsActive())
			{
				return;
			}
			this.EnsureLayoutHasRebuilt();
			this.UpdateBounds();
			Vector2 scrollDelta = data.scrollDelta;
			scrollDelta.y *= -1f;
			if (this.vertical && !this.horizontal)
			{
				if (Mathf.Abs(scrollDelta.x) > Mathf.Abs(scrollDelta.y))
				{
					scrollDelta.y = scrollDelta.x;
				}
				scrollDelta.x = 0f;
			}
			if (this.horizontal && !this.vertical)
			{
				if (Mathf.Abs(scrollDelta.y) > Mathf.Abs(scrollDelta.x))
				{
					scrollDelta.x = scrollDelta.y;
				}
				scrollDelta.y = 0f;
			}
			Vector2 vector = this.m_Content.anchoredPosition;
			this.m_Velocity += scrollDelta * this.m_ScrollSensitivity;
			if (this.m_MovementType == uGUIScrollRect.MovementType.Clamped)
			{
				vector += this.CalculateOffset(vector - this.m_Content.anchoredPosition);
			}
			this.SetContentAnchoredPosition(vector);
			this.UpdateBounds();
		}

		public virtual void OnInitializePotentialDrag(PointerEventData eventData)
		{
			if (eventData.button != PointerEventData.InputButton.Left)
			{
				return;
			}
			this.m_Velocity = Vector2.zero;
		}

		public virtual void OnBeginDrag(PointerEventData eventData)
		{
			if (eventData.button != PointerEventData.InputButton.Left)
			{
				return;
			}
			if (!this.IsActive())
			{
				return;
			}
			this.UpdateBounds();
			this.m_PointerStartLocalCursor = Vector2.zero;
			RectTransformUtility.ScreenPointToLocalPointInRectangle(this.viewRect, eventData.position, eventData.pressEventCamera, out this.m_PointerStartLocalCursor);
			this.m_ContentStartPosition = this.m_Content.anchoredPosition;
			this.m_Dragging = true;
		}

		public virtual void OnEndDrag(PointerEventData eventData)
		{
			if (eventData.button != PointerEventData.InputButton.Left)
			{
				return;
			}
			this.m_Dragging = false;
		}

		public virtual void OnDrag(PointerEventData eventData)
		{
			if (eventData.button != PointerEventData.InputButton.Left)
			{
				return;
			}
			if (!this.IsActive())
			{
				return;
			}
			Vector2 a;
			if (!RectTransformUtility.ScreenPointToLocalPointInRectangle(this.viewRect, eventData.position, eventData.pressEventCamera, out a))
			{
				return;
			}
			this.UpdateBounds();
			Vector2 b = a - this.m_PointerStartLocalCursor;
			Vector2 vector = this.m_ContentStartPosition + b;
			Vector2 b2 = this.CalculateOffset(vector - this.m_Content.anchoredPosition);
			vector += b2;
			if (this.m_MovementType == uGUIScrollRect.MovementType.Elastic)
			{
				if (b2.x != 0f)
				{
					vector.x -= uGUIScrollRect.RubberDelta(b2.x, this.m_ViewBounds.size.x);
				}
				if (b2.y != 0f)
				{
					vector.y -= uGUIScrollRect.RubberDelta(b2.y, this.m_ViewBounds.size.y);
				}
			}
			this.SetContentAnchoredPosition(vector);
		}

		protected virtual void SetContentAnchoredPosition(Vector2 position)
		{
			if (!this.m_Horizontal)
			{
				position.x = this.m_Content.anchoredPosition.x;
			}
			if (!this.m_Vertical)
			{
				position.y = this.m_Content.anchoredPosition.y;
			}
			if (position != this.m_Content.anchoredPosition)
			{
				this.m_Content.anchoredPosition = position;
				this.UpdateBounds();
			}
		}

		protected virtual void LateUpdate()
		{
			if (!this.m_Content)
			{
				return;
			}
			this.EnsureLayoutHasRebuilt();
			this.UpdateSliderVisibility();
			this.UpdateBounds();
			float unscaledDeltaTime = Time.unscaledDeltaTime;
			Vector2 vector = this.CalculateOffset(Vector2.zero);
			if (!this.m_Dragging && (vector != Vector2.zero || this.m_Velocity != Vector2.zero))
			{
				Vector2 vector2 = this.m_Content.anchoredPosition;
				for (int i = 0; i < 2; i++)
				{
					if (this.m_MovementType == uGUIScrollRect.MovementType.Elastic && vector[i] != 0f)
					{
						float num = this.m_Velocity[i];
						vector2[i] = Mathf.SmoothDamp(this.m_Content.anchoredPosition[i], this.m_Content.anchoredPosition[i] + vector[i], ref num, this.m_Elasticity, float.PositiveInfinity, unscaledDeltaTime);
						if (Mathf.Abs(num) < 1f)
						{
							num = 0f;
						}
						this.m_Velocity[i] = num;
					}
					else if (this.m_Inertia)
					{
						ref Vector2 ptr = ref this.m_Velocity;
						int index;
						this.m_Velocity[index = i] = ptr[index] * Mathf.Pow(this.m_DecelerationRate, unscaledDeltaTime);
						if (Mathf.Abs(this.m_Velocity[i]) < 1f)
						{
							this.m_Velocity[i] = 0f;
						}
						ptr = ref vector2;
						int index2;
						vector2[index2 = i] = ptr[index2] + this.m_Velocity[i] * unscaledDeltaTime;
					}
					else
					{
						this.m_Velocity[i] = 0f;
					}
				}
				if (this.m_MovementType == uGUIScrollRect.MovementType.Clamped)
				{
					vector = this.CalculateOffset(vector2 - this.m_Content.anchoredPosition);
					vector2 += vector;
				}
				if (this.m_Velocity != Vector2.zero || vector.sqrMagnitude >= 0.02f)
				{
					this.SetContentAnchoredPosition(vector2);
				}
			}
			if (this.m_Dragging && this.m_Inertia)
			{
				Vector3 b = (this.m_Content.anchoredPosition - this.m_PrevPosition) / unscaledDeltaTime;
				this.m_Velocity = Vector3.Lerp(this.m_Velocity, b, unscaledDeltaTime * 10f);
			}
			if (this.m_ViewBounds != this.m_PrevViewBounds || this.m_ContentBounds != this.m_PrevContentBounds || this.m_Content.anchoredPosition != this.m_PrevPosition)
			{
				this.UpdateSliders(vector);
				this.m_OnValueChanged.Invoke(this.normalizedPosition);
				this.UpdatePrevData();
			}
		}

		protected void UpdatePrevData()
		{
			if (this.m_Content == null)
			{
				this.m_PrevPosition = Vector2.zero;
			}
			else
			{
				this.m_PrevPosition = this.m_Content.anchoredPosition;
			}
			this.m_PrevViewBounds = this.m_ViewBounds;
			this.m_PrevContentBounds = this.m_ContentBounds;
		}

		private void UpdateSliders(Vector2 offset)
		{
			if (this.m_HorizontalSlider)
			{
				this.m_HorizontalSlider.normalizedValue = this.horizontalNormalizedPosition;
			}
			if (this.m_VerticalSlider)
			{
				this.m_VerticalSlider.normalizedValue = this.verticalNormalizedPosition;
			}
		}

		public Vector2 normalizedPosition
		{
			get
			{
				return new Vector2(this.horizontalNormalizedPosition, this.verticalNormalizedPosition);
			}
			set
			{
				this.SetNormalizedPosition(value.x, 0);
				this.SetNormalizedPosition(value.y, 1);
			}
		}

		public float horizontalNormalizedPosition
		{
			get
			{
				this.UpdateBounds();
				if (this.m_ContentBounds.size.x <= this.m_ViewBounds.size.x)
				{
					return (float)((this.m_ViewBounds.min.x <= this.m_ContentBounds.min.x) ? 0 : 1);
				}
				return (this.m_ViewBounds.min.x - this.m_ContentBounds.min.x) / (this.m_ContentBounds.size.x - this.m_ViewBounds.size.x);
			}
			set
			{
				this.SetNormalizedPosition(value, 0);
			}
		}

		public float verticalNormalizedPosition
		{
			get
			{
				this.UpdateBounds();
				if (this.m_ContentBounds.size.y <= this.m_ViewBounds.size.y)
				{
					return (float)((this.m_ViewBounds.min.y <= this.m_ContentBounds.min.y) ? 0 : 1);
				}
				return (this.m_ViewBounds.min.y - this.m_ContentBounds.min.y) / (this.m_ContentBounds.size.y - this.m_ViewBounds.size.y);
			}
			set
			{
				this.SetNormalizedPosition(value, 1);
			}
		}

		private void SetHorizontalNormalizedPosition(float value)
		{
			this.SetNormalizedPosition(value, 0);
		}

		private void SetVerticalNormalizedPosition(float value)
		{
			this.SetNormalizedPosition(value, 1);
		}

		protected virtual void SetNormalizedPosition(float value, int axis)
		{
			this.EnsureLayoutHasRebuilt();
			this.UpdateBounds();
			float num = this.m_ContentBounds.size[axis] - this.m_ViewBounds.size[axis];
			float num2 = this.m_ViewBounds.min[axis] - value * num;
			float num3 = this.m_Content.localPosition[axis] + num2 - this.m_ContentBounds.min[axis];
			Vector3 localPosition = this.m_Content.localPosition;
			if (Mathf.Abs(localPosition[axis] - num3) > 0.01f)
			{
				localPosition[axis] = num3;
				this.m_Content.localPosition = localPosition;
				this.m_Velocity[axis] = 0f;
				this.UpdateBounds();
			}
		}

		private static float RubberDelta(float overStretching, float viewSize)
		{
			return (1f - 1f / (Mathf.Abs(overStretching) * 0.55f / viewSize + 1f)) * viewSize * Mathf.Sign(overStretching);
		}

		protected override void OnRectTransformDimensionsChange()
		{
			this.SetDirty();
		}

		private bool hScrollingNeeded
		{
			get
			{
				return !Application.isPlaying || this.m_ContentBounds.size.x > this.m_ViewBounds.size.x + 1f;
			}
		}

		private bool vScrollingNeeded
		{
			get
			{
				return !Application.isPlaying || this.m_ContentBounds.size.y > this.m_ViewBounds.size.y + 1f;
			}
		}

		public virtual void CalculateLayoutInputHorizontal()
		{
		}

		public virtual void CalculateLayoutInputVertical()
		{
		}

		public virtual float minWidth
		{
			get
			{
				return -1f;
			}
		}

		public virtual float preferredWidth
		{
			get
			{
				return -1f;
			}
		}

		public virtual float flexibleWidth
		{
			get
			{
				return -1f;
			}
		}

		public virtual float minHeight
		{
			get
			{
				return -1f;
			}
		}

		public virtual float preferredHeight
		{
			get
			{
				return -1f;
			}
		}

		public virtual float flexibleHeight
		{
			get
			{
				return -1f;
			}
		}

		public virtual int layoutPriority
		{
			get
			{
				return -1;
			}
		}

		public virtual void SetLayoutHorizontal()
		{
			this.m_Tracker.Clear();
			if (this.m_HSliderExpand || this.m_VSliderExpand)
			{
				this.m_Tracker.Add(this, this.viewRect, DrivenTransformProperties.AnchoredPositionX | DrivenTransformProperties.AnchoredPositionY | DrivenTransformProperties.AnchorMinX | DrivenTransformProperties.AnchorMinY | DrivenTransformProperties.AnchorMaxX | DrivenTransformProperties.AnchorMaxY | DrivenTransformProperties.SizeDeltaX | DrivenTransformProperties.SizeDeltaY);
				this.viewRect.anchorMin = Vector2.zero;
				this.viewRect.anchorMax = Vector2.one;
				this.viewRect.sizeDelta = Vector2.zero;
				this.viewRect.anchoredPosition = Vector2.zero;
				LayoutRebuilder.ForceRebuildLayoutImmediate(this.content);
				this.m_ViewBounds = new Bounds(this.viewRect.rect.center, this.viewRect.rect.size);
				this.m_ContentBounds = this.GetBounds();
			}
			if (this.m_VSliderExpand && this.vScrollingNeeded)
			{
				this.viewRect.sizeDelta = new Vector2(-(this.m_VSliderWidth + this.m_VerticalSliderSpacing), this.viewRect.sizeDelta.y);
				LayoutRebuilder.ForceRebuildLayoutImmediate(this.content);
				this.m_ViewBounds = new Bounds(this.viewRect.rect.center, this.viewRect.rect.size);
				this.m_ContentBounds = this.GetBounds();
			}
			if (this.m_HSliderExpand && this.hScrollingNeeded)
			{
				this.viewRect.sizeDelta = new Vector2(this.viewRect.sizeDelta.x, -(this.m_HSliderHeight + this.m_HorizontalSliderSpacing));
				this.m_ViewBounds = new Bounds(this.viewRect.rect.center, this.viewRect.rect.size);
				this.m_ContentBounds = this.GetBounds();
			}
			if (this.m_VSliderExpand && this.vScrollingNeeded && this.viewRect.sizeDelta.x == 0f && this.viewRect.sizeDelta.y < 0f)
			{
				this.viewRect.sizeDelta = new Vector2(-(this.m_VSliderWidth + this.m_VerticalSliderSpacing), this.viewRect.sizeDelta.y);
			}
		}

		public virtual void SetLayoutVertical()
		{
			this.UpdateSliderLayout();
			this.m_ViewBounds = new Bounds(this.viewRect.rect.center, this.viewRect.rect.size);
			this.m_ContentBounds = this.GetBounds();
		}

		private void UpdateSliderVisibility()
		{
			uGUIScrollRect.UpdateOneSliderVisibility(this.vScrollingNeeded, this.m_Vertical, this.m_VerticalSliderVisibility, this.m_VerticalSlider);
			uGUIScrollRect.UpdateOneSliderVisibility(this.hScrollingNeeded, this.m_Horizontal, this.m_HorizontalSliderVisibility, this.m_HorizontalSlider);
		}

		private static void UpdateOneSliderVisibility(bool xScrollingNeeded, bool xAxisEnabled, uGUIScrollRect.SliderVisibility sliderVisibility, Slider slider)
		{
			if (slider)
			{
				if (sliderVisibility == uGUIScrollRect.SliderVisibility.Permanent)
				{
					if (slider.gameObject.activeSelf != xAxisEnabled)
					{
						slider.gameObject.SetActive(xAxisEnabled);
					}
				}
				else if (slider.gameObject.activeSelf != xScrollingNeeded)
				{
					slider.gameObject.SetActive(xScrollingNeeded);
				}
			}
		}

		private void UpdateSliderLayout()
		{
			if (this.m_VSliderExpand && this.m_HorizontalSlider)
			{
				this.m_Tracker.Add(this, this.m_HorizontalSliderRect, DrivenTransformProperties.AnchoredPositionX | DrivenTransformProperties.AnchorMinX | DrivenTransformProperties.AnchorMaxX | DrivenTransformProperties.SizeDeltaX);
				this.m_HorizontalSliderRect.anchorMin = new Vector2(0f, this.m_HorizontalSliderRect.anchorMin.y);
				this.m_HorizontalSliderRect.anchorMax = new Vector2(1f, this.m_HorizontalSliderRect.anchorMax.y);
				this.m_HorizontalSliderRect.anchoredPosition = new Vector2(0f, this.m_HorizontalSliderRect.anchoredPosition.y);
				if (this.vScrollingNeeded)
				{
					this.m_HorizontalSliderRect.sizeDelta = new Vector2(-(this.m_VSliderWidth + this.m_VerticalSliderSpacing), this.m_HorizontalSliderRect.sizeDelta.y);
				}
				else
				{
					this.m_HorizontalSliderRect.sizeDelta = new Vector2(0f, this.m_HorizontalSliderRect.sizeDelta.y);
				}
			}
			if (this.m_HSliderExpand && this.m_VerticalSlider)
			{
				this.m_Tracker.Add(this, this.m_VerticalSliderRect, DrivenTransformProperties.AnchoredPositionY | DrivenTransformProperties.AnchorMinY | DrivenTransformProperties.AnchorMaxY | DrivenTransformProperties.SizeDeltaY);
				this.m_VerticalSliderRect.anchorMin = new Vector2(this.m_VerticalSliderRect.anchorMin.x, 0f);
				this.m_VerticalSliderRect.anchorMax = new Vector2(this.m_VerticalSliderRect.anchorMax.x, 1f);
				this.m_VerticalSliderRect.anchoredPosition = new Vector2(this.m_VerticalSliderRect.anchoredPosition.x, 0f);
				if (this.hScrollingNeeded)
				{
					this.m_VerticalSliderRect.sizeDelta = new Vector2(this.m_VerticalSliderRect.sizeDelta.x, -(this.m_HSliderHeight + this.m_HorizontalSliderSpacing));
				}
				else
				{
					this.m_VerticalSliderRect.sizeDelta = new Vector2(this.m_VerticalSliderRect.sizeDelta.x, 0f);
				}
			}
		}

		protected void UpdateBounds()
		{
			this.m_ViewBounds = new Bounds(this.viewRect.rect.center, this.viewRect.rect.size);
			this.m_ContentBounds = this.GetBounds();
			if (this.m_Content == null)
			{
				return;
			}
			Vector3 size = this.m_ContentBounds.size;
			Vector3 center = this.m_ContentBounds.center;
			Vector2 pivot = this.m_Content.pivot;
			uGUIScrollRect.AdjustBounds(ref this.m_ViewBounds, ref pivot, ref size, ref center);
			this.m_ContentBounds.size = size;
			this.m_ContentBounds.center = center;
			if (this.movementType == uGUIScrollRect.MovementType.Clamped)
			{
				Vector3 zero = Vector3.zero;
				if (this.m_ViewBounds.max.x > this.m_ContentBounds.max.x)
				{
					zero.x = Math.Min(this.m_ViewBounds.min.x - this.m_ContentBounds.min.x, this.m_ViewBounds.max.x - this.m_ContentBounds.max.x);
				}
				else if (this.m_ViewBounds.min.x < this.m_ContentBounds.min.x)
				{
					zero.x = Math.Max(this.m_ViewBounds.min.x - this.m_ContentBounds.min.x, this.m_ViewBounds.max.x - this.m_ContentBounds.max.x);
				}
				if (this.m_ViewBounds.min.y < this.m_ContentBounds.min.y)
				{
					zero.y = Math.Max(this.m_ViewBounds.min.y - this.m_ContentBounds.min.y, this.m_ViewBounds.max.y - this.m_ContentBounds.max.y);
				}
				else if (this.m_ViewBounds.max.y > this.m_ContentBounds.max.y)
				{
					zero.y = Math.Min(this.m_ViewBounds.min.y - this.m_ContentBounds.min.y, this.m_ViewBounds.max.y - this.m_ContentBounds.max.y);
				}
				if (zero.sqrMagnitude > 0.01f)
				{
					this.m_ContentBounds = this.GetBounds();
					size = this.m_ContentBounds.size;
					center = this.m_ContentBounds.center;
					pivot = this.m_Content.pivot;
					uGUIScrollRect.AdjustBounds(ref this.m_ViewBounds, ref pivot, ref size, ref center);
					this.m_ContentBounds.size = size;
					this.m_ContentBounds.center = center;
				}
			}
		}

		internal static void AdjustBounds(ref Bounds viewBounds, ref Vector2 contentPivot, ref Vector3 contentSize, ref Vector3 contentPos)
		{
			Vector3 vector = viewBounds.size - contentSize;
			if (vector.x > 0f)
			{
				contentPos.x -= vector.x * (contentPivot.x - 0.5f);
				contentSize.x = viewBounds.size.x;
			}
			if (vector.y > 0f)
			{
				contentPos.y -= vector.y * (contentPivot.y - 0.5f);
				contentSize.y = viewBounds.size.y;
			}
		}

		private Bounds GetBounds()
		{
			if (this.m_Content == null)
			{
				return default(Bounds);
			}
			this.m_Content.GetWorldCorners(this.m_Corners);
			Matrix4x4 worldToLocalMatrix = this.viewRect.worldToLocalMatrix;
			return uGUIScrollRect.InternalGetBounds(this.m_Corners, ref worldToLocalMatrix);
		}

		internal static Bounds InternalGetBounds(Vector3[] corners, ref Matrix4x4 viewWorldToLocalMatrix)
		{
			Vector3 vector = new Vector3(float.MaxValue, float.MaxValue, float.MaxValue);
			Vector3 vector2 = new Vector3(float.MinValue, float.MinValue, float.MinValue);
			for (int i = 0; i < 4; i++)
			{
				Vector3 lhs = viewWorldToLocalMatrix.MultiplyPoint3x4(corners[i]);
				vector = Vector3.Min(lhs, vector);
				vector2 = Vector3.Max(lhs, vector2);
			}
			Bounds result = new Bounds(vector, Vector3.zero);
			result.Encapsulate(vector2);
			return result;
		}

		private Vector2 CalculateOffset(Vector2 delta)
		{
			return uGUIScrollRect.InternalCalculateOffset(ref this.m_ViewBounds, ref this.m_ContentBounds, this.m_Horizontal, this.m_Vertical, this.m_MovementType, ref delta);
		}

		internal static Vector2 InternalCalculateOffset(ref Bounds viewBounds, ref Bounds contentBounds, bool horizontal, bool vertical, uGUIScrollRect.MovementType movementType, ref Vector2 delta)
		{
			Vector2 zero = Vector2.zero;
			if (movementType == uGUIScrollRect.MovementType.Unrestricted)
			{
				return zero;
			}
			Vector2 vector = contentBounds.min;
			Vector2 vector2 = contentBounds.max;
			if (horizontal)
			{
				vector.x += delta.x;
				vector2.x += delta.x;
				if (vector.x > viewBounds.min.x)
				{
					zero.x = viewBounds.min.x - vector.x;
				}
				else if (vector2.x < viewBounds.max.x)
				{
					zero.x = viewBounds.max.x - vector2.x;
				}
			}
			if (vertical)
			{
				vector.y += delta.y;
				vector2.y += delta.y;
				if (vector2.y < viewBounds.max.y)
				{
					zero.y = viewBounds.max.y - vector2.y;
				}
				else if (vector.y > viewBounds.min.y)
				{
					zero.y = viewBounds.min.y - vector.y;
				}
			}
			return zero;
		}

		protected void SetDirty()
		{
			if (!this.IsActive())
			{
				return;
			}
			LayoutRebuilder.MarkLayoutForRebuild(this.rectTransform);
		}

		protected void SetDirtyCaching()
		{
			if (!this.IsActive())
			{
				return;
			}
			CanvasUpdateRegistry.RegisterCanvasElementForLayoutRebuild(this);
			LayoutRebuilder.MarkLayoutForRebuild(this.rectTransform);
		}

		Transform ICanvasElement.get_transform()
		{
			return base.transform;
		}

		bool ICanvasElement.IsDestroyed()
		{
			return base.IsDestroyed();
		}

		[SerializeField]
		private RectTransform m_Content;

		[SerializeField]
		private bool m_Horizontal = true;

		[SerializeField]
		private bool m_Vertical = true;

		[SerializeField]
		private uGUIScrollRect.MovementType m_MovementType = uGUIScrollRect.MovementType.Elastic;

		[SerializeField]
		private float m_Elasticity = 0.1f;

		[SerializeField]
		private bool m_Inertia = true;

		[SerializeField]
		private float m_DecelerationRate = 0.135f;

		[SerializeField]
		private float m_ScrollSensitivity = 1f;

		[SerializeField]
		private RectTransform m_Viewport;

		[SerializeField]
		private Slider m_HorizontalSlider;

		[SerializeField]
		private Slider m_VerticalSlider;

		[SerializeField]
		private uGUIScrollRect.SliderVisibility m_HorizontalSliderVisibility;

		[SerializeField]
		private uGUIScrollRect.SliderVisibility m_VerticalSliderVisibility;

		[SerializeField]
		private float m_HorizontalSliderSpacing;

		[SerializeField]
		private float m_VerticalSliderSpacing;

		[SerializeField]
		private uGUIScrollRect.ScrollRectEvent m_OnValueChanged = new uGUIScrollRect.ScrollRectEvent();

		private Vector2 m_PointerStartLocalCursor = Vector2.zero;

		protected Vector2 m_ContentStartPosition = Vector2.zero;

		private RectTransform m_ViewRect;

		protected Bounds m_ContentBounds;

		private Bounds m_ViewBounds;

		private Vector2 m_Velocity;

		private bool m_Dragging;

		private Vector2 m_PrevPosition = Vector2.zero;

		private Bounds m_PrevContentBounds;

		private Bounds m_PrevViewBounds;

		[NonSerialized]
		private bool m_HasRebuiltLayout;

		private bool m_HSliderExpand;

		private bool m_VSliderExpand;

		private float m_HSliderHeight;

		private float m_VSliderWidth;

		[NonSerialized]
		private RectTransform m_Rect;

		private RectTransform m_HorizontalSliderRect;

		private RectTransform m_VerticalSliderRect;

		private DrivenRectTransformTracker m_Tracker;

		private readonly Vector3[] m_Corners = new Vector3[4];

		public enum MovementType
		{
			Unrestricted,
			Elastic,
			Clamped
		}

		public enum SliderVisibility
		{
			Permanent,
			AutoHide,
			AutoHideAndExpandViewport
		}

		[Serializable]
		public class ScrollRectEvent : UnityEvent<Vector2>
		{
		}
	}
}