using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using Microsoft.CSharp;
using System.CodeDom;
using System.CodeDom.Compiler;

namespace SiaSun.LMS.Common
{
    public class Compiler
    {
        #region     ------定义变量和属性

        private List<string> _lsRef;
        private string _nameSpace;
        private List<string> _lsUsing;
        private string _className;
        private string _methodName;
        private string _strCode;

        public List<string> lsUsing
        {
            get { return _lsUsing; }
            set { _lsUsing = value; }
        }
        public List<string> lsRef
        {
            get { return _lsRef; }
            set { _lsRef = value; }
        }
        public string nameSpace
        {
            get { return _nameSpace; }
            set { _nameSpace = value; }
        }
        public string className
        {
            get { return _className; }
            set { _className = value; }
        }
        public string methodName
        {
            get { return _methodName; }
            set { _methodName = value; }
        }

        public string strCode
        {
            get { return _strCode; }
            set { _strCode = value; }
        }
        #endregion

        /// <summary>
        /// 构造函数
        /// </summary>
        public Compiler()
        {
            this.lsUsing = new List<string>();
            this.lsRef = new List<string>();

            this._nameSpace = "SiaSun.LMS.UI.Compiler";
            this._className = "Complier";
            this._methodName = "OutPut";

            this.lsUsing.Add("System");
            this.lsUsing.Add("System.CodeDom.Compiler");

            this.lsRef.Add("System.dll");
            this.lsUsing.Add("System.Reflection");
            this.lsRef.Add("System.Data.dll");
            this.lsRef.Add("System.Xml.dll");
        }

        /// <summary>
        /// 生成代码
        /// </summary>
        public string GenerateCode()
        {
            StringBuilder sb = new StringBuilder();

            for (int i = 0; i < this.lsUsing.Count; i++)
            {
                sb.Append(string.Format("using {0};", this.lsUsing[i]));
                sb.Append(Environment.NewLine);
            }

            sb.Append("namespace ").Append(nameSpace);
            sb.Append(Environment.NewLine);
            sb.Append("{");
            sb.Append(Environment.NewLine);

            sb.Append("public class ").Append(className);
            sb.Append(Environment.NewLine);
            sb.Append("{");
            sb.Append(Environment.NewLine);
            sb.Append(string.Format("public bool {0}(out string sResult)", this._methodName));
            sb.Append(Environment.NewLine);
            sb.Append("{");
            sb.Append(Environment.NewLine);
            sb.Append("bool bResult=true;");
            sb.Append(Environment.NewLine);
            sb.Append("sResult=string.Empty;");
            sb.Append(Environment.NewLine);
            sb.Append(strCode);
            sb.Append(Environment.NewLine);
            sb.Append("return bResult;");
            sb.Append(Environment.NewLine);
            sb.Append("}");
            sb.Append(Environment.NewLine);
            sb.Append("}");
            sb.Append(Environment.NewLine);
            sb.Append("}");

            return sb.ToString();

        }

        /// <summary>
        /// 编译代码
        /// </summary>
        public CompilerResults CompilerCode()
        {
            CSharpCodeProvider compilerPrivoder = new CSharpCodeProvider();
            //设置编译参数和属性
            CompilerParameters compilerParameters = new CompilerParameters();

            for (int i = 0; i < lsRef.Count; i++)
            {
                compilerParameters.ReferencedAssemblies.Add(lsRef[i]);
            }

            compilerParameters.GenerateExecutable = false;
            compilerParameters.GenerateInMemory = true;

            CompilerResults results = compilerPrivoder.CompileAssemblyFromSource(compilerParameters, GenerateCode());
            return results;
        }

        /// <summary>
        /// 执行代码
        /// </summary>
        public bool ExecuteCode(CompilerResults cResult, string methodName, out string sResult)
        {
            bool bResult = true;
            sResult = string.Empty;

            try
            {
                //反射
                Assembly complierAssembly = cResult.CompiledAssembly;
                //创建类实例
                object complierInstance = complierAssembly.CreateInstance(nameSpace + "." + className);
                //创建方法
                MethodInfo complierMethod = complierInstance.GetType().GetMethod(methodName);
                //调用方法
                string result = string.Empty;
                object[] obj = new object[] { result };
                bResult = Convert.ToBoolean(complierMethod.Invoke(complierInstance, obj));
                sResult = obj[0].ToString();
            }
            catch (Exception ex)
            {
                bResult = false;
                sResult = ex.Message;
            }

            return bResult;
        }

        /// <summary>
        /// 代码动态执行
        /// </summary>
        public bool Excute(out string sResult)
        {
            bool bResult = true;
            sResult = string.Empty;

            try
            {
                string strGenerateCode = this.GenerateCode();
                //获得编译结果
                CompilerResults results = this.CompilerCode();
                //查看编译结果
                if (results.Errors.HasErrors)
                {
                    string strError = string.Empty;
                    foreach (CompilerError ex in results.Errors)
                    {
                        strError += ex.ErrorText;
                    }

                    bResult = false;
                    sResult = strError;
                    return bResult;
                }

                //调用执行方法
                bResult = this.ExecuteCode(results, this._methodName, out sResult);
            }
            catch (Exception ex)
            {
                bResult = false;
                sResult = ex.Message;
            }

            return bResult;
        }
    }
}