using System;
using System.Collections.Generic;
using System.IO;
using Newtonsoft.Json;
using AibisDream.Utility;
using AibisDream.Framework;
using UnityEngine;
using Yarn.Unity;

namespace AibisDream
{
    public static class BlockPuzzleKit
    {
        /// <summary>
        /// 保存单个 BlockShapeData 到文件，确保 Key 唯一（如果 Key 已存在则更新，不存在则添加）
        /// </summary>
        /// <param name="data">要保存的数据</param>
        /// <param name="key">数据的键（用于字典存储）</param>
        /// <param name="path">保存路径，如果为空则使用默认路径</param>
        public static void SaveBlockShapeData(BlockShapeData data, string key, string path = null)
        {
            if (string.IsNullOrEmpty(path))
            {
                path = ConstRef.BlockShapeDataPath;
            }

            // 确保目录存在
            string directory = Path.GetDirectoryName(path);
            if (!string.IsNullOrEmpty(directory) && !Directory.Exists(directory))
            {
                Directory.CreateDirectory(directory);
            }

            // 读取现有字典（如果文件存在）
            Dictionary<string, BlockShapeData> dataDict;
            if (File.Exists(path))
            {
                try
                {
                    dataDict = JsonUtil.ReadBeanDict<BlockShapeData>(path) ?? new Dictionary<string, BlockShapeData>();
                }
                catch (Exception e)
                {
                    Debug.LogWarning($"读取现有 BlockShapeData 文件失败，将创建新文件: {e.Message}");
                    dataDict = new Dictionary<string, BlockShapeData>();
                }
            }
            else
            {
                dataDict = new Dictionary<string, BlockShapeData>();
            }

            // 更新或添加数据（确保 Key 唯一）
            dataDict[key] = data;

            // 保存整个字典
            JsonUtil.SaveBean(dataDict, path);
        }


        /// <summary>
        /// 从文件加载单个 BlockShapeData
        /// </summary>
        /// <param name="key">数据的键</param>
        /// <param name="path">文件路径，如果为空则使用默认路径</param>
        /// <param name="data">加载的数据</param>
        /// <returns>是否加载成功</returns>
        public static bool TryLoadBlockShapeData(string key, out BlockShapeData data, string path = null)
        {
            if (string.IsNullOrEmpty(path))
            {
                path = ConstRef.BlockShapeDataPath;
            }

            try
            {
                if (!File.Exists(path))
                {
                    data = default;
                    return false;
                }

                var dict = JsonUtil.ReadBeanDict<BlockShapeData>(path);
                var infoDict = JsonUtil.ReadBeanDict<BlockShapeInfo>(ConstRef.BlockShapeInfoPath);
                if (dict != null && dict.ContainsKey(key))
                {
                    data = dict[key];
                    data.blockShapeInfo = infoDict[key];
                    return true;
                }

                data = default;
                return false;
            }
            catch (Exception e)
            {
                Debug.LogError($"加载 BlockShapeData 失败: {e.Message}");
                data = default;
                return false;
            }
        }

        /// <summary>
        /// 从文件加载单个 BlockPuzzleData
        /// </summary>
        /// <param name="key">数据的键</param>
        /// <param name="data">加载的数据</param>
        /// <returns>是否加载成功</returns>
        public static bool TryLoadBlockPuzzleData(string key, out BlockPuzzleData data)
        {
            var path = ConstRef.BlockPuzzleDataPath;
            // 加载配置
            try
            {
                if (!File.Exists(path))
                {
                    data = default;
                    return false;
                }

                var dict = JsonUtil.ReadBeanDict<BlockPuzzleData>(path);
                if (dict != null && dict.ContainsKey(key))
                {
                    data = dict[key];
                    return true;
                }

                data = default;
                return false;
            }
            catch (Exception e)
            {
                Debug.LogError($"加载 BlockPuzzleData 失败: {e.Message}");
                data = default;
                return false;
            }
        }

        /// <summary>
        /// 保存单个 BlockPuzzleData 到文件，确保 Key 唯一（如果 Key 已存在则更新，不存在则添加）
        /// </summary>
        /// <param name="data">要保存的数据</param>
        /// <param name="key">数据的键（用于字典存储）</param>
        /// <param name="path">保存路径，如果为空则使用默认路径</param>
        public static void SaveBlockPuzzleData(BlockPuzzleData data, string key, string path = null)
        {
            if (string.IsNullOrEmpty(path))
            {
                path = ConstRef.BlockPuzzleDataPath;
            }

            // 确保目录存在
            string directory = Path.GetDirectoryName(path);
            if (!string.IsNullOrEmpty(directory) && !Directory.Exists(directory))
            {
                Directory.CreateDirectory(directory);
            }

            // 读取现有字典（如果文件存在）
            Dictionary<string, BlockPuzzleData> dataDict;
            if (File.Exists(path))
            {
                try
                {
                    dataDict = JsonUtil.ReadBeanDict<BlockPuzzleData>(path) ?? new Dictionary<string, BlockPuzzleData>();
                }
                catch (Exception e)
                {
                    Debug.LogWarning($"读取现有 BlockPuzzleData 文件失败，将创建新文件: {e.Message}");
                    dataDict = new Dictionary<string, BlockPuzzleData>();
                }
            }
            else
            {
                dataDict = new Dictionary<string, BlockPuzzleData>();
            }

            // 更新或添加数据（确保 Key 唯一）
            dataDict[key] = data;

            // 保存整个字典
            JsonUtil.SaveBean(dataDict, path);
        }

        // ---------------------- 碰撞箱计算 ----------------------
        /// <summary>
        /// 将网格数组转换为多边形顶点数组
        /// </summary>
        /// <param name="grid">二维数组，值为1的格子表示填充区域</param>
        /// <returns>按顺序排列的多边形顶点数组，可以围成闭合多边形</returns>
        public static Vector2[] GridToPolygonVertices(int[,] grid)
        {
            if (grid == null || grid.GetLength(0) == 0 || grid.GetLength(1) == 0)
                return new Vector2[0];

            int width = grid.GetLength(0);
            int height = grid.GetLength(1);

            // 查找起始边界点
            Vector2Int? startPoint = FindStartBoundaryPoint(grid, width, height);
            if (!startPoint.HasValue)
                return new Vector2[0];

            // 边界追踪
            List<Vector2> vertices = TraceBoundary(grid, width, height, startPoint.Value);

            if (vertices.Count == 0)
                return new Vector2[0];

            // 顶点优化：移除共线点
            vertices = OptimizeVertices(vertices);

            return vertices.ToArray();
        }

        /// <summary>
        /// 查找起始边界点
        /// 找到第一个值为1的格子，确定其边界上的起始追踪点
        /// </summary>
        private static Vector2Int? FindStartBoundaryPoint(int[,] grid, int width, int height)
        {
            // 从左下角开始，按行扫描，找到第一个值为1的格子
            for (int j = 0; j < height; j++)
            {
                for (int i = 0; i < width; i++)
                {
                    if (grid[i, j] == 1)
                    {
                        // 找到第一个填充格子，检查其下边界（最可能的外边界）
                        // 如果下边界是外边界，返回左下角点
                        if (j == 0 || (j > 0 && grid[i, j - 1] == 0))
                        {
                            // 返回格子(i,j)的左下角点坐标
                            return new Vector2Int(i, j);
                        }
                        // 否则检查左边界
                        else if (i == 0 || (i > 0 && grid[i - 1, j] == 0))
                        {
                            return new Vector2Int(i, j);
                        }
                    }
                }
            }

            return null;
        }

        /// <summary>
        /// 边界追踪：从起始点开始，沿着边界顺时针追踪，记录所有边界顶点
        /// 使用边界边收集和连接的方法
        /// 边长固定为2，所有坐标使用整数
        /// </summary>
        private static List<Vector2> TraceBoundary(int[,] grid, int width, int height, Vector2Int startCell)
        {
            // 收集所有边界边：每条边用起点和终点表示（整数坐标）
            List<(Vector2Int start, Vector2Int end)> boundaryEdges = CollectBoundaryEdges(grid, width, height);

            if (boundaryEdges.Count == 0)
                return new List<Vector2>();

            // 构建顶点邻接表（直接使用整数坐标）
            Dictionary<Vector2Int, List<Vector2Int>> adjacency = BuildAdjacencyList(boundaryEdges);

            if (adjacency.Count == 0)
                return new List<Vector2>();

            // 找到起始顶点（最左下角的顶点）
            Vector2Int startVertex = FindStartVertex(adjacency);

            // 沿着邻接表追踪，形成有序顶点序列
            List<Vector2> vertices = TraceVertices(adjacency, startVertex);

            return vertices;
        }

        /// <summary>
        /// 收集所有边界边
        /// 坐标系统：格子(i,j)的中心为(i*2, j*2)，边长为2
        /// 格子(i,j)的四个角点为：(i*2-1, j*2-1), (i*2+1, j*2-1), (i*2+1, j*2+1), (i*2-1, j*2+1)
        /// </summary>
        private static List<(Vector2Int start, Vector2Int end)> CollectBoundaryEdges(int[,] grid, int width, int height)
        {
            List<(Vector2Int, Vector2Int)> edges = new List<(Vector2Int, Vector2Int)>();

            for (int i = 0; i < width; i++)
            {
                for (int j = 0; j < height; j++)
                {
                    if (grid[i, j] != 1)
                        continue;

                    // 计算格子(i,j)的四个角点坐标（整数）
                    int left = i * 2 - 1;
                    int right = i * 2 + 1;
                    int bottom = j * 2 - 1;
                    int top = j * 2 + 1;

                    // 检查四个方向的边界
                    // 下边界（从左下角到右下角）
                    if (j == 0 || (j > 0 && grid[i, j - 1] == 0))
                    {
                        edges.Add((new Vector2Int(left, bottom), new Vector2Int(right, bottom)));
                    }

                    // 右边界（从右下角到右上角）
                    if (i == width - 1 || (i < width - 1 && grid[i + 1, j] == 0))
                    {
                        edges.Add((new Vector2Int(right, bottom), new Vector2Int(right, top)));
                    }

                    // 上边界（从右上角到左上角）
                    if (j == height - 1 || (j < height - 1 && grid[i, j + 1] == 0))
                    {
                        edges.Add((new Vector2Int(right, top), new Vector2Int(left, top)));
                    }

                    // 左边界（从左上角到左下角）
                    if (i == 0 || (i > 0 && grid[i - 1, j] == 0))
                    {
                        edges.Add((new Vector2Int(left, top), new Vector2Int(left, bottom)));
                    }
                }
            }

            return edges;
        }

        /// <summary>
        /// 构建顶点邻接表
        /// 直接使用整数坐标，无需量化
        /// </summary>
        private static Dictionary<Vector2Int, List<Vector2Int>> BuildAdjacencyList(List<(Vector2Int start, Vector2Int end)> edges)
        {
            Dictionary<Vector2Int, List<Vector2Int>> adjacency = new Dictionary<Vector2Int, List<Vector2Int>>();

            foreach (var edge in edges)
            {
                Vector2Int key1 = edge.start;
                Vector2Int key2 = edge.end;

                if (!adjacency.ContainsKey(key1))
                    adjacency[key1] = new List<Vector2Int>();
                if (!adjacency.ContainsKey(key2))
                    adjacency[key2] = new List<Vector2Int>();

                if (!adjacency[key1].Contains(key2))
                    adjacency[key1].Add(key2);
                if (!adjacency[key2].Contains(key1))
                    adjacency[key2].Add(key1);
            }

            return adjacency;
        }

        /// <summary>
        /// 找到起始顶点（最左下角的顶点）
        /// </summary>
        private static Vector2Int FindStartVertex(Dictionary<Vector2Int, List<Vector2Int>> adjacency)
        {
            Vector2Int start = new Vector2Int(int.MaxValue, int.MaxValue);

            foreach (var key in adjacency.Keys)
            {
                if (key.y < start.y || (key.y == start.y && key.x < start.x))
                {
                    start = key;
                }
            }

            return start;
        }

        /// <summary>
        /// 沿着邻接表追踪顶点，形成有序序列（顺时针）
        /// 直接使用整数坐标，最后转换为Vector2返回
        /// </summary>
        private static List<Vector2> TraceVertices(Dictionary<Vector2Int, List<Vector2Int>> adjacency, Vector2Int start)
        {
            List<Vector2> vertices = new List<Vector2>();

            Vector2Int current = start;
            Vector2Int? previous = null;

            do
            {
                // 将整数坐标转换为Vector2
                Vector2 currentPos = new Vector2(current.x, current.y);

                // 避免重复添加相同顶点（除非是起点）
                if (vertices.Count == 0 || vertices[vertices.Count - 1] != currentPos)
                {
                    vertices.Add(currentPos);
                }

                // 找到下一个顶点：选择使方向变化最小的邻居（顺时针）
                List<Vector2Int> neighbors = adjacency[current];
                Vector2Int? next = null;

                if (neighbors.Count == 1)
                {
                    // 只有一个邻居
                    next = neighbors[0];
                }
                else if (neighbors.Count == 2)
                {
                    // 有两个邻居，选择不是前一个的那个
                    foreach (var neighbor in neighbors)
                    {
                        if (!previous.HasValue || neighbor != previous.Value)
                        {
                            next = neighbor;
                            break;
                        }
                    }
                }
                else
                {
                    // 多个邻居，选择角度最小的（顺时针方向）
                    Vector2 currentVec = new Vector2(current.x, current.y);
                    Vector2 direction;

                    if (previous.HasValue)
                    {
                        Vector2 prevVec = new Vector2(previous.Value.x, previous.Value.y);
                        direction = (currentVec - prevVec).normalized;
                    }
                    else
                    {
                        // 起始点，选择最下方的邻居（顺时针起始方向）
                        direction = new Vector2(1, 0); // 向右
                    }

                    float bestAngle = float.MaxValue;
                    foreach (var neighbor in neighbors)
                    {
                        if (previous.HasValue && neighbor == previous.Value)
                            continue;

                        Vector2 neighborVec = new Vector2(neighbor.x, neighbor.y);
                        Vector2 toNeighbor = (neighborVec - currentVec).normalized;

                        // 计算从当前方向到邻居方向的角度（顺时针）
                        float angle = GetClockwiseAngle(direction, toNeighbor);
                        if (angle < bestAngle)
                        {
                            bestAngle = angle;
                            next = neighbor;
                        }
                    }
                }

                if (!next.HasValue)
                    break;

                previous = current;
                current = next.Value;

            } while (current != start && vertices.Count < adjacency.Count * 2);

            return vertices;
        }

        /// <summary>
        /// 计算从向量a到向量b的顺时针角度（0到2π）
        /// </summary>
        private static float GetClockwiseAngle(Vector2 a, Vector2 b)
        {
            float angleA = Mathf.Atan2(a.y, a.x);
            float angleB = Mathf.Atan2(b.y, b.x);
            float angle = angleB - angleA;

            // 转换为0到2π范围
            if (angle < 0)
                angle += 2 * Mathf.PI;

            return angle;
        }

        /// <summary>
        /// 优化顶点：移除共线的顶点，保留关键转折点
        /// </summary>
        private static List<Vector2> OptimizeVertices(List<Vector2> vertices)
        {
            if (vertices.Count <= 3)
                return vertices;

            List<Vector2> optimized = new List<Vector2>();
            const float epsilon = 0.0001f; // 浮点数比较阈值

            for (int i = 0; i < vertices.Count; i++)
            {
                Vector2 prev = vertices[(i - 1 + vertices.Count) % vertices.Count];
                Vector2 current = vertices[i];
                Vector2 next = vertices[(i + 1) % vertices.Count];

                // 计算两个向量
                Vector2 v1 = current - prev;
                Vector2 v2 = next - current;

                // 检查是否共线（叉积接近0）且方向相同（点积大于0）
                float crossProduct = v1.x * v2.y - v1.y * v2.x;
                float dotProduct = Vector2.Dot(v1.normalized, v2.normalized);

                // 如果共线且方向相同，跳过当前点
                if (Mathf.Abs(crossProduct) < epsilon && dotProduct > 0.99f)
                {
                    continue;
                }

                optimized.Add(current);
            }

            return optimized;
        }
    }

    public static class BlockPuzzleYarnCommand
    {
        [YarnCommand("init_block_puzzle")]
        public static void InitBlockPuzzle(string puzzleName)
        {
            if (BlockPuzzleKit.TryLoadBlockPuzzleData(puzzleName, out var blockPuzzleData))
            {
                BlockPuzzleSystem.Instance.Initialize(blockPuzzleData);
            }
            else
            {
                Debug.LogError($"加载 BlockPuzzleData 失败: {puzzleName}");
            }
        }

        [YarnCommand("clear_block_puzzle")]
        public static void ClearBlockPuzzle()
        {
            BlockPuzzleSystem.Instance.ClearGame();
        }

        // [YarnCommand("reset_block_puzzle")]
        // public static void ResetBlockPuzzle()
        // {
        //     BlockPuzzleSystem.Instance.ResetGame();
        // }
    }

    [Serializable]
    public struct BlockPuzzleData
    {
        public string puzzleName;
        public int gridWidth;
        public int gridHeight;
        public float cellSize;
        // 网格内Shape
        public GridShapeData[] gridShapeDataInfos;
        // 验证器
        public string validatorName;
    }

    [Serializable]
    public struct GridShapeData
    {
        public string shapeKey;
        public Vector2Int rootCell;
        public RotationAngle rotationAngle;
        public bool isDraggable;
    }

    [Serializable]
    public struct BlockShapeData
    {
        public int shapeId;
        public string shapeName;
        public int width;
        public int height;
        public float cellSize;
        public string originalPatternStr;
        public string spritePath;

        [Header("额外限制")]
        public bool extraLimits;
        public Vector2Int rootLimit;
        public RotationAngle rotationAngleLimit;

        [JsonIgnore]
        [HideInInspector]
        public BlockShapeInfo blockShapeInfo;

        public Sprite GetSprite()
        {
            return ResourceKit.LoadAssetSync<Sprite>(spritePath);
        }
    }

    [Serializable]
    public struct BlockShapeInfo
    {
        public string shapeName;

        public BlockPuzzleParamValue paramValue;
        public string shapeDescription;

        public string[] states;

        public string buttonImagePath;

        public Sprite GetButtonImage()
        {
            return ResourceKit.LoadAssetSync<Sprite>(buttonImagePath);
        }
    }

    [Serializable]
    public struct BlockPuzzleParamValue
    {
        public int power;
        public int noise;
        public int heat;
    }
}