Lamba-Pin Code Generator

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace CodeGenerator.Vapor.Core
{
    sealed class LambdaPin : ICodeGenerator
    {
        public string OutputPath
        {
            get { return "Core/Lambda-Pin.cs"; }
        }

        public void WriteTo(TextWriter file)
        {
            file.WriteLine("// Generated by \"CodeGenerator/Vapor.Core/Lambda-Pin.cs\"");
            file.WriteLine("//  DO NOT MAKE CHANGES TO THIS FILE, AS THEY WILL BE DISCARDED!");
            file.WriteLine("using System;");
            file.WriteLine();
            file.WriteLine("namespace Vapor");
            file.WriteLine("{");
            file.WriteLine("\tpublic static partial class Lambda");
            file.WriteLine("\t{");

            for (int i = 1; i <= 16; ++i)
            {
                if (i == 5)
                    file.WriteLine("\t\t#if !COMPACT_FRAMEWORK");
                file.WriteLine(MakePinAction(i));
                file.WriteLine(MakePinFunc(i));
            }
            file.WriteLine("\t\t#endif//!COMPACT_FRAMEWORK");

            file.WriteLine("\t}");
            file.WriteLine("}");
        }

        private static string MakePinAction(int args)
        {
            var builder = new StringBuilder();
            builder.Append("\t\tpublic static Action Pin<");
            for (int i = 0; i < args; ++i)
                builder.AppendFormat("T{0}, ", i);
            builder.Remove(builder.Length - 2, 2);
            builder.AppendLine(">");

            builder.AppendLine("\t\t\t(");

            builder.Append("\t\t\t\tthis Action<");
            for (int i = 0; i < args; ++i)
                builder.AppendFormat("T{0}, ", i);
            builder.Remove(builder.Length - 2, 2);
            builder.AppendLine("> action,");

            for (int i = 0; i < args - 1; ++i)
                builder.AppendFormat("\t\t\t\tT{0} arg{0},\r\n", i);
            builder.AppendFormat("\t\t\t\tT{0} arg{0}\r\n", args - 1);

            builder.AppendLine("\t\t\t)");

            builder.AppendLine("\t\t{");

            builder.AppendFormat("\t\t\treturn () => action(");
            for (int i = 0; i < args; ++i)
                builder.AppendFormat("arg{0}, ", i);
            builder.Remove(builder.Length - 2, 2);
            builder.AppendLine(");");

            builder.AppendLine("\t\t}");

            return builder.ToString();
        }

        private static string MakePinFunc(int args)
        {
            Func<string, string, string> genString = (format, seperator) =>
                {
                    return Generate.SeperateString(
                        Generate.Sequence(args),
                        format,
                        seperator);
                };

            var builder = new StringBuilder();
            builder.Append("\t\tpublic static Func<TResult> Pin<");
            builder.Append(genString("T{0}", ", "));
            builder.AppendLine(", TResult>");

            builder.AppendLine("\t\t\t(");

            builder.Append("\t\t\t\tthis Func<");
            builder.Append(genString("T{0}", ", "));
            builder.AppendLine(", TResult> func,");

            builder.AppendLine(genString("\t\t\t\tT{0} arg{0}", ",\r\n"));
            builder.AppendLine("\t\t\t)");

            builder.AppendLine("\t\t{");

            builder.AppendFormat("\t\t\treturn () => func(");
            builder.Append(genString("arg{0}", ", "));
            builder.AppendLine(");");

            builder.AppendLine("\t\t}");

            return builder.ToString();
        }
    }
}