////////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  Note:   Singularity pipe test program.
//
using System;
using System.Collections;

using Microsoft.Singularity;
using Microsoft.Singularity.Channels;
using Microsoft.SingSharp.Reflection;
using Microsoft.Singularity.Applications;
using Microsoft.Singularity.Directory;
using Microsoft.Singularity.Io;
using Microsoft.Singularity.Configuration;
using Microsoft.Singularity.ConsoleApplications;

[assembly: Transform(typeof(ApplicationResourceTransform))]

namespace Microsoft.Singularity.Applications
{
    [ConsoleCategory(HelpMessage="Echo stdin to stdout", DefaultAction=true)]
    internal class Parameters
    {
        [InputEndpoint("data")]
        public readonly TRef<UnicodePipeContract.Exp:READY> Stdin;

        [OutputEndpoint("data")]
        public readonly TRef<UnicodePipeContract.Imp:READY> Stdout;

        [Endpoint]
        public readonly TRef<DirectoryServiceContract.Imp:Start> nsRef;

        reflective internal Parameters();

        internal int AppMain() {
            return Echo.AppMain(this);
        }
    }

    public class Echo
    {
            // kinda dumb...
        private static bool CommandLineSyntaxCheck(string! commandLine)
        {
            int quoteCount = 0;
            for (int i = 0; i < commandLine.Length; i++) {
                if (commandLine[i] == '\'') {
                    quoteCount++;
                }
            }

            return (quoteCount % 2 == 0);
        }

        private static bool InSeparators(char c, char []! separators)
        {
            for (int i = 0; i < separators.Length; i++) {
                if (separators[i] == c)
                    return true;
            }
            return false;
        }

        private static ArrayList! Tokenize(string! input, int last,
                                           char []! separators)
        {
            ArrayList tokens = new ArrayList();

            for (int i = 0; i <= last;) {
                // Skip separators
                while (i <= last && InSeparators(input[i], separators)) {
                    i++;
                }

                if (i > last)
                    break;

                // Try to slurp word
                int start = i;
                while (i <= last &&
                       !InSeparators(input[i], separators) &&
                       input[i] != '\'')
                {
                    i++;
                }
                if (i != start) {
                    tokens.Add(input.Substring(start, i - start));
                }

                // Skip separators
                while (i <= last && InSeparators(input[i], separators)) {
                    i++;
                }

                if (i > last)
                    break;

                // Try to quoted slurp word
                if (input[i] == '\'') {
                    start = i;
                    i++;
                    while (i <= last && input[i] != '\'') {
                        i++;
                    }

                    if (i <= last && input[i] == '\'') {
                        tokens.Add(input.Substring(start + 1, i - start - 1));
                        i++;
                    }
                    else {
                        tokens.Add(input.Substring(start, i - start));
                        i++;
                    }
                }
            } // end for

            return tokens;
        }

        private static void BreakCommandLine(string!       input,
                                             char []!      separators,
                                             out string    command,
                                             out string[]! commandArguments,
                                             out bool      isBackground)
        {
            isBackground = false;

            if (!CommandLineSyntaxCheck(input)) {
                command = "";
                commandArguments = new string[0];
                return;
            }

            // Scan for trailing ampersand first
            int last = input.Length - 1;
            while (last > 0 && InSeparators(input[last], separators)) {
                last--;
            }

            if (input[last] == '&') {
                isBackground = true;
                last--;
            }

            ArrayList tokens = Tokenize(input, last, separators);

            if (tokens.Count == 0) {
                command = "";
                commandArguments = new string[0];
                isBackground = false;
                return;
            }

            command = (string) tokens[0];
            commandArguments = new string [tokens.Count];
            for (int i = 0; i < tokens.Count; i++) {
                commandArguments[i] = (string) tokens[i];
            }
        }

        internal static int AppMain(Parameters! config)
        {
            string commandName;
            string[]! commandArguments;
            bool isBackground;

            DirectoryServiceContract.Imp ds = ((!) config.nsRef).Acquire();
            if (ds == null) {
                throw new Exception("Unable to acquire handle to the Directory Service root");
            }
            ds.RecvSuccess();
            assert ds.InState(DirectoryServiceContract.Ready.Value);

            JobControl  jobControl =  ConsoleJob.StartOutputPipeThread();
            ParameterProcessor parameterProcessor = new ParameterProcessor();

            while (true) {
                Console.Write("enter job>");
                string a = Console.ReadLine();
                if (a == null || a == "q") {
                    break;
                }
                if (a == "") continue;

                BreakCommandLine(a, new char[] {' '},
                                out commandName, out commandArguments,
                                out isBackground);

                ConsoleJob job = new ConsoleJob();
                if (job.CreateProcess(ds, jobControl, commandArguments, parameterProcessor)) {
                    job.Start();
                    if (!isBackground) job.WaitForJob();
                }
                job.Dispose();
                Console.WriteLine(a);
            }
            jobControl.Dispose();
            delete ds;
            return 0;
        }
    }
}