zszq-trs/YLErpDAL/Modules/RiskEngine/RuleCompiler.cs

using Microsoft.CodeAnalysis.CSharp.Scripting;
using Microsoft.CodeAnalysis.Scripting;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;

namespace YLErp.Modules.RiskEngine
{
    /// <summary>
    /// Roslyn 脚本全局变量容器
    /// CSharpScript 执行时通过此对象传递 DataMap
    /// </summary>
    public class ScriptGlobals
    {
        /// <summary>
        /// 数据字典：key=表名/前缀，value=对应数据对象
        /// </summary>
        public Dictionary<string, object> DataMap { get; set; }
    }

    /// <summary>
    /// 规则编译器（Roslyn 版）
    ///
    /// 编译时机：规则定义时（零运行时解析开销）
    /// 执行方式：判风控时直接调用 rule.CompiledScript(context) → bool
    ///
    /// 相比表达式树方案的优势：
    /// - 代码简洁：生成 C# 字符串即可，无需手动拼接 Expression 节点
    /// - 灵活性高：天然支持多条件 AND/OR、复杂运算、未来可扩展任意 C# 语法
    /// - 可调试：生成的脚本代码可直接阅读和理解
    ///
    /// 示例：
    ///   FormulaJson: { "conditions": [{"variableCode":"trade.StockEqvNotional","operator":">","value":100000000}] }
    ///   生成脚本：Convert.ToDecimal(((YLErp.DBModels.trade)DataMap["trade"]).StockEqvNotional) > 100000000m
    ///   编译结果：Func&lt;RiskContext, bool&gt;（内部通过 Roslyn 编译缓存）
    /// </summary>
    public static class RuleCompiler
    {
        /// <summary>
        /// 变量编码 → 类型全名的映射
        /// 用于 Roslyn 脚本中的类型强转，如 ((YLErp.DBModels.trade)DataMap["trade"])
        /// </summary>
        private static readonly Dictionary<string, string> VariableTypeMap = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
        {
            ["trade"] = "YLErp.DBModels.trade",
            ["swap_position"] = "YLErp.DBModels.swap_position",
            ["client"] = "YLErp.DBModels.client",
            ["credit"] = "YLErp.DBModels.credit",
            ["client_marginrate"] = "YLErp.DBModels.client_marginrate",
            ["market"] = "YLErp.DBModels.market",
            ["calc"] = "YLErp.DBModels.calc",
            ["sys"] = "YLErp.DBModels.sys",
            ["eod_swap_position"] = "YLErp.DBModels.eod_swap_position",
            ["realtime_trade_risk"] = "YLErp.DBModels.realtime_trade_risk",
        };

        /// <summary>
        /// 将规则编译为可执行委托，并写入 rule.CompiledScript
        /// 调用时机：规则创建时 / 规则加载时 / 缓存刷新时
        /// </summary>
        public static void Compile(this RiskRule rule)
        {
            if (string.IsNullOrWhiteSpace(rule.FormulaJson))
            {
                throw new ArgumentException("规则 FormulaJson 不能为空", nameof(rule.FormulaJson));
            }

            // 1. 解析 FormulaJson
            var conditions = ParseFormulaJson(rule.FormulaJson);

            // 2. 生成 Roslyn C# 脚本代码
            string scriptCode = BuildScriptCode(conditions);

            // 3. 编译脚本（只编译一次，后续直接执行）
            var compiled = CompileScript(scriptCode);

            // 4. 写入规则（不持久化，仅内存缓存）
            rule.CompiledScript = compiled;
        }

        /// <summary>
        /// 解析 FormulaJson，提取条件列表
        /// </summary>
        private static List<(string variableCode, string op, object value, string variableType)> ParseFormulaJson(string formulaJson)
        {
            var result = new List<(string, string, object, string)>();
            var jObj = JObject.Parse(formulaJson);
            var conditions = jObj["conditions"] as JArray;

            if (conditions == null || !conditions.Any())
            {
                throw new ArgumentException("FormulaJson 中缺少 conditions");
            }

            foreach (var cond in conditions)
            {
                string variableCode = cond["variableCode"]?.Value<string>();
                string op = cond["operator"]?.Value<string>();
                object value = cond["value"]?.Value<object>();
                string variableType = cond["variableType"]?.Value<string>() ?? "numeric";

                if (string.IsNullOrWhiteSpace(variableCode) || string.IsNullOrWhiteSpace(op))
                {
                    throw new ArgumentException("条件中缺少 variableCode 或 operator");
                }

                result.Add((variableCode, op, value, variableType));
            }

            return result;
        }

        /// <summary>
        /// 根据条件列表生成 Roslyn C# 脚本代码
        /// 多条件自动用 &&（AND）连接
        /// </summary>
        private static string BuildScriptCode(List<(string variableCode, string op, object value, string variableType)> conditions)
        {
            var exprParts = new List<string>();

            foreach (var (variableCode, op, value, variableType) in conditions)
            {
                // 解析 variableCode：前缀.属性名
                var parts = variableCode.Split('.');
                if (parts.Length != 2)
                {
                    throw new ArgumentException($"variableCode 格式不正确：{variableCode}");
                }

                string prefix = parts[0].Trim().ToLower();
                string propertyName = parts[1].Trim();

                if (!VariableTypeMap.TryGetValue(prefix, out string typeFullName))
                {
                    throw new ArgumentException($"未知前缀：{prefix}");
                }

                // 格式化阈值
                string valueLiteral = FormatValueLiteral(value, variableType);

                // 格式化操作符
                string csharpOp = FormatOperator(op);

                // 生成单条件表达式
                // Convert.ToDecimal(((YLErp.DBModels.trade)DataMap["trade"]).StockEqvNotional) > 100000000m
                string expr = $"Convert.ToDecimal((({typeFullName})DataMap[\"{prefix}\"]).{propertyName}) {csharpOp} {valueLiteral}";
                exprParts.Add(expr);
            }

            // 多条件用 && 连接
            return string.Join(" && ", exprParts);
        }

        /// <summary>
        /// 用 Roslyn 编译 C# 脚本代码为可执行委托
        /// </summary>
        private static Func<RiskContext, bool> CompileScript(string scriptCode)
        {
            // 配置编译选项：引用必要的程序集
            var options = ScriptOptions.Default
                .WithReferences(
                    typeof(RiskContext).Assembly,      // YLErpDAL
                    typeof(YLErp.DBModels.trade).Assembly // Model 所在程序集
                )
                .WithImports("System");

            // 创建脚本（尚未执行，仅编译）
            var script = CSharpScript.Create<bool>(scriptCode, options, globalsType: typeof(ScriptGlobals));

            // 编译（提前发现语法错误）
            var compilation = script.GetCompilation();
            var diagnostics = compilation.GetDiagnostics();
            var errors = diagnostics.Where(d => d.Severity == Microsoft.CodeAnalysis.DiagnosticSeverity.Error).ToList();
            if (errors.Any())
            {
                string errorMsg = string.Join("; ", errors.Select(e => e.GetMessage()));
                throw new InvalidOperationException($"脚本编译失败：{errorMsg}\n脚本代码：{scriptCode}");
            }

            // 生成可调用委托
            var runner = script.CreateDelegate();

            // 包装为同步的 Func<RiskContext, bool>
            return ctx =>
            {
                var globals = new ScriptGlobals { DataMap = ctx.DataMap };
                try
                {
                    return runner(globals).GetAwaiter().GetResult();
                }
                catch (Exception ex)
                {
                    // 脚本执行异常（如空引用、类型转换失败）视为规则不触发
                    // TODO: 记录日志
                    return false;
                }
            };
        }

        /// <summary>
        /// 格式化阈值为 C# 字面量
        /// </summary>
        private static string FormatValueLiteral(object value, string variableType)
        {
            if (value == null) return "null";

            string strValue = value.ToString();

            // 数值类型统一加 m 后缀（decimal）
            if (variableType == "numeric" || variableType == "number")
            {
                if (decimal.TryParse(strValue, NumberStyles.Any, CultureInfo.InvariantCulture, out decimal d))
                {
                    return d.ToString(CultureInfo.InvariantCulture) + "m";
                }
            }

            // 布尔
            if (variableType == "boolean" || variableType == "bool")
            {
                if (bool.TryParse(strValue, out bool b))
                {
                    return b ? "true" : "false";
                }
            }

            // 日期
            if (variableType == "date" && DateTime.TryParse(strValue, out DateTime dt))
            {
                return $"DateTime.Parse(\"{dt:yyyy-MM-dd}\")";
            }

            // 字符串（兜底）
            return $"\"{strValue.Replace("\\", "\\\\").Replace("\"", "\\\"")}\"";
        }

        /// <summary>
        /// 将操作符统一为 C# 操作符
        /// </summary>
        private static string FormatOperator(string op)
        {
            return op?.Trim() switch
            {
                "=" or "==" => "==",
                "!=" or "≠" => "!=",
                ">" => ">",
                "<" => "<",
                ">=" => ">=",
                "<=" => "<=",
                _ => throw new ArgumentException($"不支持的操作符：{op}")
            };
        }
    }
}