using HandyControl.Tools.Extension;
using PropertyGridLib.Controls;
using System;
using System.Collections.Generic;
using System.Linq;
using TeamAAS.Communication;
using TeamAAS.FlowEditor.Execution;
using TeamAAS.FlowEditor.Models;
using TeamAAS.FlowEngine;

namespace TeamAAS.FlowEngine.FormulaData
{
    /// <summary>
    /// 给「组合模块输入参数 SourceValue」用的公式树数据源。
    /// 查外层主流程中组合模块节点的前置节点结果（而不是子流程内部节点）。
    /// 依赖 <see cref="PluginLoader.ParentGroupModel"/> 判断上下文。
    /// </summary>
    [Serializable]
    public class InputSourceDataProvider : IFormulaTreeProvider
    {
        /// <summary>
        /// 生成公式树节点列表：
        /// 1) 全局变量（Gloab）
        /// 2) 主流程中组合模块节点的所有前置节点输出结果
        /// </summary>
        public List<FormulaTreeNode> GetFormulaTree(PropertyItem propertyItem)
        {
            var nodes = new List<FormulaTreeNode>();
            try
            {
                var select = PluginLoader.Instance.ParentGroupModel;
                if (select == null) return nodes;

                var flowId = select.FlowId;
                var findName = select.NodeName;
                // 使用选中节点所属流程绑定的注册表（编辑态=Debug，监控态挂接运行图=Main）
                var registry = PluginLoader.Instance.SelectFlow?.Registry ?? ResultRegistry.Debug;
                registry.GetFlowResults(flowId, out var flowResults);
                flowResults.DeleteIfExistsKey(findName);

                if (propertyItem.Value == null)
                    propertyItem.Value = new object();

                var targetType = propertyItem.Value.GetType();
                var formulaType = propertyItem.PropertyType;

                nodes.AddRange(flowResults.Select(kvp =>
                    new FormulaTreeNode
                    {
                        Header = kvp.Key,
                        Children = kvp.Value
                            .Where(p => targetType == null || targetType == typeof(object)
                                || (p.Value != null && (p.Value.GetType() == targetType || p.Value.GetType() == formulaType)))
                            .Select(p =>
                                new FormulaTreeNode
                                {
                                    Header = p.Key,
                                    Formula = $"&{{{kvp.Key}.{p.Key}}}"
                                }).ToList()
                    }).ToList());

                // 全局变量
                try
                {
                    registry.RefreshGlobalVariables();
                    var gloabNode = new FormulaTreeNode
                    {
                        Header = "Gloab",
                        Children = GlobalVariableManager.Instance.Variables
                            .Where(v => !string.IsNullOrWhiteSpace(v.Name))
                            .Select(v => new FormulaTreeNode
                            {
                                Header = v.Name,
                                Formula = $"&{{Gloab.{v.Name}}}"
                            }).ToList()
                    };
                    if (gloabNode.Children.Count > 0)
                        nodes.Insert(0, gloabNode);
                }
                catch { }
            }
            catch { }
            return nodes;
        }

        /// <summary>
        /// 反向 BFS 追溯指定节点的所有前置节点名称（通过连接线追溯到起点）。
        /// </summary>
        private static HashSet<string> GetPredecessorNodeNames(string graphId, string nodeId)
        {
            var result = new HashSet<string>();
            var graph = FindGraphById(graphId);
            if (graph == null) return result;

            var predecessorIds = new HashSet<string>();
            var queue = new Queue<string>();
            foreach (var conn in graph.Connections)
            {
                if (conn.TargetNodeId == nodeId) queue.Enqueue(conn.SourceNodeId);
            }
            while (queue.Count > 0)
            {
                var cur = queue.Dequeue();
                if (predecessorIds.Add(cur))
                {
                    foreach (var conn in graph.Connections)
                    {
                        if (conn.TargetNodeId == cur) queue.Enqueue(conn.SourceNodeId);
                    }
                }
            }
            foreach (var node in graph.Nodes)
            {
                if (predecessorIds.Contains(node.NodeId))
                    result.Add(node.NodeName);
            }
            return result;
        }

        /// <summary>
        /// 按 GraphId 查找 FlowGraph：先查顶层 FlowTabs，找不到再递归所有组合模块 SubGraph。
        /// </summary>
        private static FlowGraph FindGraphById(string graphId)
        {
            var flowTabs = PluginLoader.Instance.FlowTabs;
            if (flowTabs != null)
            {
                var tab = flowTabs.FirstOrDefault(t => t.Graph != null && t.Graph.GraphId == graphId);
                if (tab?.Graph != null) return tab.Graph;

                foreach (var t in flowTabs)
                {
                    if (t?.Graph == null) continue;
                    var found = FindSubGraphById(t.Graph, graphId);
                    if (found != null) return found;
                }
            }
            return null;
        }

        /// <summary>
        /// 在图中递归查找所有 SubGraph（支持任意嵌套组合模块）。
        /// </summary>
        private static FlowGraph FindSubGraphById(FlowGraph parent, string graphId)
        {
            foreach (var node in parent.Nodes)
            {
                var model = node.PluginModel?.GetModel;
                if (model == null) continue;
                var graphProp = model.GetType().GetProperty("SubGraph");
                if (graphProp?.GetValue(model) is FlowGraph sub)
                {
                    if (sub.GraphId == graphId) return sub;
                    var nested = FindSubGraphById(sub, graphId);
                    if (nested != null) return nested;
                }
            }
            return null;
        }
    }
}