using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.Emit;
using Microsoft.CodeAnalysis;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
namespace Shentun.Peis.DiagnosisFunctions
{
    public class CodeBuilder
    {
        private static List<MetadataReference> _references = new List<MetadataReference>();
        /// <summary>
        /// 编译前的初始化，只需要一次
        /// </summary>
        /// <returns></returns>
        static CodeBuilder()
        {
            _references = new List<MetadataReference>();

            // 元数据引用
            if (_references == null || _references.Count == 0)
            {
                _references = new List<MetadataReference>()
        {
            MetadataReference.CreateFromFile(typeof(System.Uri).Assembly.Location),
            MetadataReference.CreateFromFile(typeof(System.Linq.Enumerable).Assembly.Location),
            MetadataReference.CreateFromFile(typeof(object).Assembly.Location),
            MetadataReference.CreateFromFile(typeof(System.IO.File).Assembly.Location),
            MetadataReference.CreateFromFile(Assembly.Load("System.Runtime").Location),
            MetadataReference.CreateFromFile(Assembly.Load("System.Collections").Location),
            MetadataReference.CreateFromFile(Assembly.LoadFrom(AppDomain.CurrentDomain.BaseDirectory+"Shentun.Peis.Application.dll").Location),
        };
            }
            //Assembly as1 = Assembly.LoadFrom(AppDomain.CurrentDomain.BaseDirectory + "mscorlib.dll");
            //MetadataReference metadataReference = _references.Find((o => o.Display.Contains("mscorlib.dll")));
            //if (_references.Find((o => o.Display.Contains("mscorlib.dll"))) == null)
            //{
            //    _references.Add(MetadataReference.CreateFromFile(as1.Location));
            //}
        }

        //public CodeBuilder() 
        //{
        //}
        //public Assembly CreateCode(string code)
        //{
        //    //var domain = new NatashaDomain("key");
        //    //var domain = DomainManagement.Random();
        //    NatashaManagement.Preheating();
        //    Path.GetRandomFileName();
        //    using (DomainManagement.Create("myDomain").CreateScope())
        //    {
        //        AssemblyCSharpBuilder builder = new AssemblyCSharpBuilder();
        //        builder.Add(code);
        //        var func = builder.GetDelegateFromShortName<Func<string>>("Test", "GetName");
        //    }

        //    return myAssembly;
        //}
        public Assembly GenerateAssemblyFromCode(string code)
        {
            Assembly assembly = null;

            // 丛代码中转换表达式树
            SyntaxTree syntaxTree = CSharpSyntaxTree.ParseText(code);
            // 随机程序集名称
            //string assemblyName = Path.GetRandomFileName();
            var assemblyName = "_" + Guid.NewGuid().ToString("D");
            //assemblyName =  System.Reflection.Assembly.GetExecutingAssembly().GetName().Name;
            //assemblyName = "Shentun.Peis.Application";
            var syntaxTrees = new SyntaxTree[] { syntaxTree };
            // 引用
            var references = _references;// referencedAssemblies.Select(x => MetadataReference.CreateFromFile(x.Location));
            var options = new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary);

            // 创建编译对象
            CSharpCompilation compilation = CSharpCompilation.Create(assemblyName, syntaxTrees, references, options);

            using (var ms = new MemoryStream())
            {
                // 将编译好的IL代码放入内存流
                EmitResult result = compilation.Emit(ms);

                // 编译失败，提示
                if (!result.Success)
                {
                    IEnumerable<Diagnostic> failures = result.Diagnostics.Where(diagnostic =>
                                diagnostic.IsWarningAsError ||
                                diagnostic.Severity == DiagnosticSeverity.Error);
                    foreach (Diagnostic diagnostic in failures)
                    {
                        Console.Error.WriteLine("{0}: {1}", diagnostic.Id, diagnostic.GetMessage());
                    }
                }
                else
                {
                    // 编译成功，从内存中加载编译好的程序集
                    ms.Seek(0, SeekOrigin.Begin);
                    assembly = Assembly.Load(ms.ToArray());
                }
            }
            return assembly;
        }
    }

}