Twiggery Scripting Language

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.Windows.Forms;
using System.Drawing;
using System.IO;
using System.Threading;
using num = System.Single;
using arguments = System.Collections.Generic.List<object>;

namespace Twiggery.Plugin.IO
{
    public class IO
    {
        internal class FileAttrib
        {
            public FileStream fileStream = null;
            public StreamReader streamReader = null;
            public StreamWriter streamWriter = null;

            public FileAttrib(FileStream fs, StreamWriter sw)
            {
                fileStream = fs;
                streamWriter = sw;
            }
            public FileAttrib(FileStream fs, StreamReader sr)
            {
                fileStream = fs;
                streamReader = sr;
            }
            public FileAttrib(FileStream fs, StreamReader sr, StreamWriter sw)
            {
                fileStream = fs;
                streamReader = sr;
                streamWriter = sw;
            }

            public void Close()
            {
                if (null != streamWriter)
                {
                    streamWriter.Close();
                }
                if (null != streamReader)
                {
                    streamReader.Close();
                }
                if (null != fileStream)
                {
                    fileStream.Close();
                }
            }
        }

        private static int idf = 0;
        private static Dictionary<int, FileAttrib> files = new Dictionary<int, FileAttrib>();

        public static void openFile(arguments args)
        {
            string access = (string)args[0];
            string name = (string)args[1];
            args.Clear();

            num result = (num)(-1);

            switch (access)
            {
                case "rw":
                    {
                        FileStream fs = new FileStream(name, FileMode.OpenOrCreate, FileAccess.ReadWrite);
                        StreamWriter sw = new StreamWriter(fs);
                        StreamReader sr = new StreamReader(fs);
                        FileAttrib fa = new FileAttrib(fs, sw);
                        fa.streamReader = sr;
                        files[++idf] = fa;
                        result = (num)idf;
                    }
                    break;
                case "w":
                    {
                        FileStream fs = new FileStream(name, FileMode.OpenOrCreate, FileAccess.Write);
                        fs.Close();
                        fs = new FileStream(name, FileMode.Truncate, FileAccess.Write);
                        StreamWriter sw = new StreamWriter(fs);
                        FileAttrib fa = new FileAttrib(fs, sw);
                        files[++idf] = fa;
                        result = (num)idf;
                    }
                    break;
                case "r":
                    {
                        FileStream fs = new FileStream(name, FileMode.Open, FileAccess.Read);
                        StreamReader sr = new StreamReader(fs);
                        FileAttrib fa = new FileAttrib(fs, sr);
                        files[++idf] = fa;
                        result = (num)idf;
                    }
                    break;
                default:
                    throw new Exception("Invalid file access option " + access);
            }
            args.Add(result);
        }

        private static void closeFile(arguments args)
        {
            int id = (int)(num)args[0];
            if (files.ContainsKey(id))
            {
                FileAttrib fa = files[id];
                fa.Close();
                files.Remove(id);
            }
        }

        private static void writeFile(arguments args)
        {
            int id = (int)(num)args[args.Count - 1];
            if (files.ContainsKey(id))
            {
                FileAttrib fa = files[id];
                args.RemoveAt(args.Count - 1);
                for (int i = args.Count - 1; i >= 0; i--)
                {
                    object obj = args[i];
                    if (obj.Equals("\\n"))
                    {
                        obj = "\r\n";
                    }
                    fa.streamWriter.Write(obj);
                }
                args.Clear();
            }
        }

        public static void readFile(arguments args)
        {
            int count = 0;
            int start = 0;
            int id = 0;
            if (args.Count == 3)
            {
                count = (int)(num)args[0];
                start = (int)(num)args[1];
                id = (int)(num)args[2];
            }
            else if (args.Count == 1)
            {
                count = -1;
                start = -1;
                id = (int)(num)args[0];
            }
            else
            {
                throw new Exception("Invalid read file arguments");
            }
            args.Clear();
            if (files.ContainsKey(id))
            {
                FileAttrib fa = files[id];
                if (null != fa.streamReader)
                {
                    string str_buf = null;
                    if (-1 == count)
                    {
                        str_buf = fa.streamReader.ReadLine();
                    }
                    else
                    {
                        char[] buffer = new char[count];
                        fa.streamReader.Read(buffer, start, count);
                        str_buf = new string(buffer);
                    }
                    num result = num.Parse(str_buf);
                    args.Add(result);
                }
            }
        }
    }
}