////////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  File:   Varargs.sg
//
//  Note:   Test __arglist parameters
//
using System;
using System.Text;

namespace Microsoft.Singularity.Applications
{
    public class Varargs
    {
        public static int Main(String[]! args)
        {
            string name = "VarArgs.x86";
            int len = 1; 
            int code = Printf("Invoked command with name '%s' and %d arguments", __arglist(name, len));
            Console.WriteLine("Varargs exiting.");
            return code;
        }

        public static int Printf(string! fmt, __arglist) {
            return Decode(fmt, __arglist);
        }

        public static int Decode(string! fmt, RuntimeArgumentHandle art) {

            StringBuilder sb = new StringBuilder();
            ArgIterator ai = new ArgIterator(art);

            int length = fmt.Length;
            for (int index = 0; index < length; index++) {

                char c = fmt[index];

                if (c == '%') {
                    index++;
                    if (index < length) {
                        c = fmt[index];
                        switch (c) {
                        case '%':
                            sb.Append('%');
                            break;
                        case 's':
                            if (ai.GetRemainingCount() > 0) {
                                TypedReference tr = ai.GetNextArg();
                                Type t = __reftype(tr);
                                if (t == typeof(string)) {
                                    string s = __refvalue(tr, string);
                                    sb.Append(s);
                                }
                                else {
                                    Console.WriteLine("Invalid argument for %s: {0}", t.ToString());
                                    return 1;
                                }
                            }
                            else {
                                Console.WriteLine("Insufficient number of arguments for %s");
                                return 1;
                            }
                            break;

                        case 'd':
                            if (ai.GetRemainingCount() > 0) {
                                TypedReference tr = ai.GetNextArg();
                                Type t = __reftype(tr);
                                if (t == typeof(int)) {
                                    int i = __refvalue(tr, int);
                                    sb.Append(i.ToString());
                                }
                                else {
                                    Console.WriteLine("Invalid argument for %i: {0}", t.ToString());
                                    return 1;
                                }
                            }
                            else {
                                Console.WriteLine("Insufficient number of arguments for %i");
                                return 1;
                            }
                            break;

                        default:
                            Console.WriteLine("Unknown format directive %{0}", c);
                            return 1;
                        }
                    }
                    else {
                        Console.WriteLine("Error in format: end of string after %");
                        return -1;
                    }
                }
                else {
                    sb.Append(c);
                }
            }
            Console.WriteLine(sb.ToString());
            return 0;
        }
    }
}