using System;

using System.Diagnostics;

using System.Diagnostics.CodeAnalysis;

using System.IO;



namespace Mercurial.Versions

{

    /// <summary>

    /// This base class handles Mercurial &lt; 1.8.

    /// </summary>

    [SuppressMessage("Microsoft.Usage", "CA2243:AttributeStringLiteralsShouldParseCorrectly", Justification = "There is more advanced parsing here to handle version ranges, so this is not necessary.")]

    [MercurialVersion("", "1.7")]

    public class MercurialVersionPre18 : MercurialVersionBase

    {

        /// <summary>

        /// This method will wait for lingering POSIX-style file locks to dissipate before

        /// continuing, to get around problems with such locks in pre-1.8 Mercurial.

        /// </summary>

        /// <param name="repositoryPath">

        /// The path to the repository that the locks exists in.

        /// </param>

        /// <exception cref="ArgumentNullException">

        /// <para><paramref name="repositoryPath"/> is <c>null</c> or empty.</para>

        /// </exception>

        public override void WaitForLocksToDissipate(string repositoryPath)

        {

            string repositoryFolderPath = Path.Combine(repositoryPath, ".hg");

            if (!Directory.Exists(repositoryFolderPath))

                return;



            string lockPath = Path.Combine(repositoryFolderPath, "lock");

            string wlockPath = Path.Combine(repositoryFolderPath, "wlock");



            foreach (string path in new[] { lockPath, wlockPath })

            {

                Stopwatch sw = Stopwatch.StartNew();

                try

                {

                    while (sw.ElapsedMilliseconds < 1000)

                    {

                        try

                        {

                            File.Create(path).Dispose();

                            break;

                        }

                        catch (IOException)

                        {

                            // swallow this

                        }

                    }

                }

                finally

                {

                    sw = Stopwatch.StartNew();

                    while (sw.ElapsedMilliseconds < 1000)

                    {

                        try

                        {

                            File.Delete(path);

                            break;

                        }

                        catch (IOException)

                        {

                            // swallow this

                        }

                    }

                }

            }

        }

    }

}