ZhenShiXunYouJi2/Assets/Scripts/CIG/RecyclerGridLayoutGroup.cs

using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

namespace CIG
{
    [AddComponentMenu("Layout/Recycler Grid Layout Group", 153)]
    public class RecyclerGridLayoutGroup : LayoutGroup
    {
        public enum RecyclerConstraint
        {
            FixedColumnCount,
            FixedRowCount
        }

        public enum Corner
        {
            UpperLeft
        }

        [SerializeField]
        protected Corner _startCorner;

        [SerializeField]
        protected GridLayoutGroup.Axis _startAxis;

        [SerializeField]
        protected Vector2 _cellSize = new Vector2(100f, 100f);

        [SerializeField]
        protected Vector2 _spacing = Vector2.zero;

        [SerializeField]
        protected RecyclerConstraint _constraint;

        [SerializeField]
        protected int _constraintCount = 2;

        [SerializeField]
        protected int _recyclerChildCount = 2;

        [SerializeField]
        private ObjectPool _objectPool;

        private DrivenRectTransformTracker _tracker;

        private int _maxChildren;

        private Func<GameObject, int, bool> _initCallback;

        private List<GameObject> _instances = new List<GameObject>();

        private Dictionary<int, int> _indexMapping = new Dictionary<int, int>();

        private float _lastPosition;

        private int _startIndex;

        public Corner StartCorner
        {
            get
            {
                return _startCorner;
            }
            set
            {
                SetProperty(ref _startCorner, value);
            }
        }

        public GridLayoutGroup.Axis StartAxis => _startAxis;

        public Vector2 CellSize
        {
            get
            {
                return _cellSize;
            }
            set
            {
                SetProperty(ref _cellSize, value);
            }
        }

        public Vector2 Spacing
        {
            get
            {
                return _spacing;
            }
            set
            {
                SetProperty(ref _spacing, value);
            }
        }

        public RecyclerConstraint Constraint => _constraint;

        public int ConstraintCount
        {
            get
            {
                return _constraintCount;
            }
            set
            {
                SetProperty(ref _constraintCount, Mathf.Max(1, value));
            }
        }

        public int RecyclerChildCount
        {
            get
            {
                return _recyclerChildCount;
            }
            set
            {
                SetProperty(ref _recyclerChildCount, Mathf.Max(1, value));
            }
        }

        public int MaxChildren
        {
            get
            {
                return _maxChildren;
            }
            set
            {
                SetProperty(ref _maxChildren, Mathf.Max(1, value));
            }
        }

        protected override void OnEnable()
        {
            base.OnEnable();
            _tracker.Add(this, base.rectTransform, DrivenTransformProperties.SizeDelta);
        }

        protected override void OnDisable()
        {
            base.OnDisable();
            _tracker.Clear();
        }

        private void Update()
        {
            if (MaxChildren == RecyclerChildCount)
            {
                return;
            }
            float num;
            if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                Vector2 anchoredPosition = base.rectTransform.anchoredPosition;
                num = anchoredPosition.x * -1f;
            }
            else
            {
                if (_constraint != 0)
                {
                    UnityEngine.Debug.LogWarningFormat("Unknown constraint '{0}'", _constraint);
                    return;
                }
                Vector2 anchoredPosition2 = base.rectTransform.anchoredPosition;
                num = anchoredPosition2.y;
            }
            if (Mathf.Approximately(num, _lastPosition))
            {
                return;
            }
            _lastPosition = num;
            float num2;
            if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                Vector2 cellSize = CellSize;
                float x = cellSize.x;
                Vector2 spacing = Spacing;
                num2 = x + spacing.x;
            }
            else
            {
                if (_constraint != 0)
                {
                    UnityEngine.Debug.LogWarningFormat("Unknown constraint '{0}'", _constraint);
                    return;
                }
                Vector2 cellSize2 = CellSize;
                float y = cellSize2.y;
                Vector2 spacing2 = Spacing;
                num2 = y + spacing2.y;
            }
            int num3 = Mathf.Clamp(Mathf.FloorToInt((_lastPosition - num2) / num2 * (float)_constraintCount), 0, Mathf.Max(0, MaxChildren - RecyclerChildCount));
            if (_startIndex != num3)
            {
                _startIndex = num3;
                UpdateInstances();
            }
        }

        private void SetPosition(float position)
        {
            if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                Vector2 anchoredPosition = base.rectTransform.anchoredPosition;
                anchoredPosition.x = position * -1f;
                base.rectTransform.anchoredPosition = anchoredPosition;
            }
            else if (_constraint == RecyclerConstraint.FixedColumnCount)
            {
                Vector2 anchoredPosition2 = base.rectTransform.anchoredPosition;
                anchoredPosition2.y = position;
                base.rectTransform.anchoredPosition = anchoredPosition2;
            }
            else
            {
                UnityEngine.Debug.LogWarningFormat("Unknown constraint '{0}'", _constraint);
            }
        }

        public void Init(int maxChildren, ObjectPool objectPool, Func<GameObject, int, bool> initCallback)
        {
            _objectPool = objectPool;
            Init(maxChildren, initCallback);
        }

        public void Init(int maxChildren, Func<GameObject, int, bool> initCallback)
        {
            MaxChildren = maxChildren;
            _initCallback = initCallback;
            _lastPosition = 0f;
            _startIndex = 0;
            if (_objectPool.AvailableInstances < _recyclerChildCount)
            {
                UnityEngine.Debug.LogWarningFormat("Insufficient elements available. Expected {0} elements, found {1}", _recyclerChildCount, _objectPool.AvailableInstances);
            }
            PopInstances();
            UpdateInstances();
        }

        public void Init(int maxChildren, List<GameObject> instances, Func<GameObject, int, bool> initCallback)
        {
            MaxChildren = maxChildren;
            _initCallback = initCallback;
            _lastPosition = 0f;
            _startIndex = 0;
            if (instances.Count < _recyclerChildCount)
            {
                UnityEngine.Debug.LogErrorFormat("Insufficient elements available. Expected {0} elements, found {1}", _recyclerChildCount, instances.Count);
            }
            int count = instances.Count;
            for (int i = 0; i < count; i++)
            {
                _instances.Add(instances[i]);
                _indexMapping[i] = -1;
            }
            UpdateInstances();
        }

        public void PushInstances()
        {
            if (_objectPool != null)
            {
                _objectPool.Push(_instances);
            }
            _instances.Clear();
            _indexMapping.Clear();
        }

        public void ScrollToElement(int index)
        {
            index = Mathf.Clamp(index, 0, MaxChildren - 1);
            RecyclerConstraint constraint = _constraint;
            float num = (constraint != RecyclerConstraint.FixedRowCount && constraint == RecyclerConstraint.FixedColumnCount) ? (_cellSize.y + _spacing.y) : (_cellSize.x + _spacing.x);
            SetPosition((float)index * num);
        }

        public override void CalculateLayoutInputHorizontal()
        {
            base.CalculateLayoutInputHorizontal();
            int num = 0;
            int num2 = 0;
            if (_constraint == RecyclerConstraint.FixedColumnCount)
            {
                num = (num2 = _constraintCount);
            }
            else if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                num = (num2 = Mathf.CeilToInt((float)_maxChildren / (float)_constraintCount - 0.001f));
            }
            else
            {
                num = 1;
                num2 = Mathf.CeilToInt(Mathf.Sqrt(_maxChildren));
            }
            float num3 = base.padding.horizontal;
            Vector2 cellSize = CellSize;
            float x = cellSize.x;
            Vector2 spacing = Spacing;
            float num4 = num3 + (x + spacing.x) * (float)num;
            Vector2 spacing2 = Spacing;
            float totalMin = Mathf.Max(0f, num4 - spacing2.x);
            float num5 = base.padding.horizontal;
            Vector2 cellSize2 = CellSize;
            float x2 = cellSize2.x;
            Vector2 spacing3 = Spacing;
            float num6 = num5 + (x2 + spacing3.x) * (float)num2;
            Vector2 spacing4 = Spacing;
            SetLayoutInputForAxis(totalMin, Mathf.Max(0f, num6 - spacing4.x), -1f, 0);
        }

        public override void CalculateLayoutInputVertical()
        {
            int num = 0;
            if (_constraint == RecyclerConstraint.FixedColumnCount)
            {
                num = Mathf.CeilToInt((float)_maxChildren / (float)_constraintCount - 0.001f);
            }
            else if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                num = _constraintCount;
            }
            else
            {
                Vector2 size = base.rectTransform.rect.size;
                float x = size.x;
                float num2 = x - (float)base.padding.horizontal;
                Vector2 spacing = Spacing;
                float num3 = num2 + spacing.x + 0.001f;
                Vector2 cellSize = CellSize;
                float x2 = cellSize.x;
                Vector2 spacing2 = Spacing;
                int num4 = Mathf.Max(1, Mathf.FloorToInt(num3 / (x2 + spacing2.x)));
                num = Mathf.CeilToInt((float)_maxChildren / (float)num4);
            }
            float num5 = base.padding.vertical;
            Vector2 cellSize2 = CellSize;
            float y = cellSize2.y;
            Vector2 spacing3 = Spacing;
            float num6 = num5 + (y + spacing3.y) * (float)num;
            Vector2 spacing4 = Spacing;
            float num7 = Mathf.Max(0f, num6 - spacing4.y);
            SetLayoutInputForAxis(num7, num7, -1f, 1);
        }

        public override void SetLayoutHorizontal()
        {
            SetCellsAlongAxis(0);
        }

        public override void SetLayoutVertical()
        {
            SetCellsAlongAxis(1);
        }

        private void PopInstances()
        {
            for (int i = 0; i < _recyclerChildCount; i++)
            {
                GameObject item = _objectPool.Pop(base.transform);
                _instances.Add(item);
                _indexMapping[i] = -1;
            }
        }

        private void UpdateInstances()
        {
            if (_initCallback != null)
            {
                if (_instances.Count < _recyclerChildCount)
                {
                    UnityEngine.Debug.LogWarningFormat("Insufficient elements available. Expected {0} elements, found {1}", _recyclerChildCount, _instances.Count);
                }
                int count = _instances.Count;
                for (int i = 0; i < count; i++)
                {
                    _instances[i].SetActive(i < _recyclerChildCount);
                    int num = _startIndex + i;
                    if (_indexMapping[i] != num)
                    {
                        _indexMapping[i] = num;
                        if (!_initCallback(_instances[i], _indexMapping[i]))
                        {
                            _instances[i].SetActive(value: false);
                        }
                    }
                }
            }
            SetCellsAlongAxis(1);
        }

        private void SetCellsAlongAxis(int axis)
        {
            base.rectTransform.SetSizeWithCurrentAnchors((RectTransform.Axis)axis, GetTotalPreferredSize(axis));
            if (axis == 0)
            {
                for (int i = 0; i < base.rectChildren.Count; i++)
                {
                    RectTransform rectTransform = base.rectChildren[i];
                    m_Tracker.Add(this, rectTransform, DrivenTransformProperties.AnchoredPositionX | DrivenTransformProperties.AnchoredPositionY | DrivenTransformProperties.AnchorMinX | DrivenTransformProperties.AnchorMinY | DrivenTransformProperties.AnchorMaxX | DrivenTransformProperties.AnchorMaxY | DrivenTransformProperties.SizeDeltaX | DrivenTransformProperties.SizeDeltaY);
                    rectTransform.anchorMin = Vector2.up;
                    rectTransform.anchorMax = Vector2.up;
                    rectTransform.sizeDelta = CellSize;
                }
                return;
            }
            int num = 1;
            int num2 = 1;
            if (_constraint == RecyclerConstraint.FixedColumnCount)
            {
                num = _constraintCount;
                num2 = Mathf.CeilToInt((float)_maxChildren / (float)num - 0.001f);
            }
            else if (_constraint == RecyclerConstraint.FixedRowCount)
            {
                num2 = _constraintCount;
                num = Mathf.CeilToInt((float)_maxChildren / (float)num2 - 0.001f);
            }
            int num3 = (int)StartCorner % 2;
            int num4 = (int)StartCorner / 2;
            int num5;
            int num6;
            int num7;
            if (StartAxis == GridLayoutGroup.Axis.Horizontal)
            {
                num5 = num;
                num6 = Mathf.Clamp(num, 1, base.rectChildren.Count);
                num7 = Mathf.Clamp(num2, 1, Mathf.CeilToInt((float)base.rectChildren.Count / (float)num5));
            }
            else
            {
                num5 = num2;
                num7 = Mathf.Clamp(num2, 1, base.rectChildren.Count);
                num6 = Mathf.Clamp(num, 1, Mathf.CeilToInt((float)base.rectChildren.Count / (float)num5));
            }
            float num8 = num6;
            Vector2 cellSize = CellSize;
            float num9 = num8 * cellSize.x;
            float num10 = num6 - 1;
            Vector2 spacing = Spacing;
            float x = num9 + num10 * spacing.x;
            float num11 = num7;
            Vector2 cellSize2 = CellSize;
            float num12 = num11 * cellSize2.y;
            float num13 = num7 - 1;
            Vector2 spacing2 = Spacing;
            Vector2 vector = new Vector2(x, num12 + num13 * spacing2.y);
            Vector2 vector2 = new Vector2(GetStartOffset(0, vector.x), GetStartOffset(1, vector.y));
            for (int j = 0; j < base.rectChildren.Count; j++)
            {
                int value;
                if (!_indexMapping.TryGetValue(j, out value))
                {
                    value = j;
                }
                int num14;
                int num15;
                if (StartAxis == GridLayoutGroup.Axis.Horizontal)
                {
                    num14 = value % num5;
                    num15 = value / num5;
                }
                else
                {
                    num14 = value / num5;
                    num15 = value % num5;
                }
                if (num3 == 1)
                {
                    num14 = num6 - 1 - num14;
                }
                if (num4 == 1)
                {
                    num15 = num7 - 1 - num15;
                }
                SetChildAlongAxis(base.rectChildren[j], 0, vector2.x + (CellSize[0] + Spacing[0]) * (float)num14, CellSize[0]);
                SetChildAlongAxis(base.rectChildren[j], 1, vector2.y + (CellSize[1] + Spacing[1]) * (float)num15, CellSize[1]);
            }
        }
    }
}