using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO;
using System.Linq;
using NDesk.Options;
using Sep.Git.Tfs.Core;
using StructureMap;

namespace Sep.Git.Tfs.Commands
{
    [Pluggable("bootstrap")]
    [RequiresValidGitRepository]
    [Description("bootstrap [parent-commit]")]
    public class Bootstrap : GitTfsCommand
    {
        private readonly RemoteOptions _remoteOptions;
        private readonly Globals _globals;
        private readonly TextWriter _stdout;

        public Bootstrap(RemoteOptions remoteOptions, Globals globals, TextWriter stdout)
        {
            _remoteOptions = remoteOptions;
            _globals = globals;
            _stdout = stdout;
        }

        public OptionSet OptionSet
        {
            get { return _remoteOptions.OptionSet; }
        }

        public int Run()
        {
            return Run("HEAD");
        }

        public int Run(string commitish)
        {
            var tfsParents = _globals.Repository.GetLastParentTfsCommits(commitish, true);
            foreach (var parent in tfsParents)
            {
                _globals.Repository.CommandNoisy("log", "-1", parent.GitCommit);
                if (parent.Remote.IsDerived)
                {
                    var remoteId = GetRemoteId(parent);
                    var remote = _globals.Repository.CreateTfsRemote(new RemoteInfo
                    {
                        Id = remoteId,
                        Url = parent.Remote.TfsUrl,
                        Repository = parent.Remote.TfsRepositoryPath,
                        RemoteOptions = _remoteOptions,
                    });
                    remote.UpdateTfsHead(parent.GitCommit, parent.ChangesetId);
                    _stdout.WriteLine("-> new remote " + remote.Id);
                }
                else
                {
                    if (parent.Remote.MaxChangesetId < parent.ChangesetId)
                    {
                        long oldChangeset = parent.Remote.MaxChangesetId;
                        _globals.Repository.MoveTfsRefForwardIfNeeded(parent.Remote);
                        _stdout.WriteLine("-> existing remote {0} (updated from changeset {1})", parent.Remote.Id, oldChangeset);
                    }
                    else
                    {
                        _stdout.WriteLine("-> existing remote {0} (up to date)", parent.Remote.Id);
                    }
                }
                _stdout.WriteLine();
            }
            return GitTfsExitCodes.OK;
        }

        private string GetRemoteId(TfsChangesetInfo parent)
        {
            if (IsAvailable(GitTfsConstants.DefaultRepositoryId))
                return GitTfsConstants.DefaultRepositoryId;

            var hostname = new Uri(parent.Remote.TfsUrl).Host.Replace(".", "-");
            var remoteId = hostname;
            var suffix = 0;
            while (!IsAvailable(remoteId))
                remoteId = hostname + "-" + (suffix++);
            return remoteId;
        }

        private bool IsAvailable(string remoteName)
        {
            return !_globals.Repository.HasRemote(remoteName);
        }
    }
}