using System;
using System.Data.SqlClient;
using Microsoft.SharePoint;
namespace VersionCommentFaker
{
    class Program
    {
        static int Main(string[] args)
        {
            if (args.Length != 3)
                return Usage();
            using (SPSite site = new SPSite(args[0]))
            {
                using (SPWeb web = site.OpenWeb())
                {
                    SPFile file=web.GetFile(args[0]);
 
                    if (file.UIVersionLabel == args[1])
                        return ChangeCurrentComment(site, file.UniqueId, file.UIVersion, args[2]);
 
                    foreach (SPFileVersion fileVersion in file.Versions)
                    {
                        if (fileVersion.VersionLabel == args[1])
                            return ChangeComment(site, file.UniqueId, fileVersion.ID, args[2]);
                    }
                    Console.WriteLine("Version not found");
                }
            }
            return 1;
        }
 
        private static int ChangeCurrentComment(SPSite site, Guid FileId, int version, string newComment)
        {
            using (SqlConnection conn = new SqlConnection(site.ContentDatabase.DatabaseConnectionString))
            {
                SqlCommand cmd = new SqlCommand(
                    "UPDATE dbo.AllDocs SET CheckinComment=@comment "+
                    "WHERE SiteId=@SiteId AND Id=@FileId AND UIVersion=@VersionId", conn);
                cmd.Parameters.AddWithValue("@comment", newComment);
                cmd.Parameters.AddWithValue("@SiteId", site.ID.ToString("D"));
                cmd.Parameters.AddWithValue("@FileId", FileId.ToString("D"));
                cmd.Parameters.AddWithValue("@VersionId", version);
                conn.Open();
                int rows = cmd.ExecuteNonQuery();
                conn.Close();
                if (rows == 1)
                    Console.WriteLine("CheckinComment was updated");
            }
            return 0;
        }
        private static int ChangeComment(SPSite site, Guid FileId, int version, string newComment)
        {
            using (SqlConnection conn = new SqlConnection(site.ContentDatabase.DatabaseConnectionString))
            {
                SqlCommand cmd = new SqlCommand(
                    "UPDATE dbo.AllDocVersions SET CheckinComment=@comment "+
                    "WHERE SiteId=@SiteId AND Id=@FileId AND Version=@VersionId", conn);
                cmd.Parameters.AddWithValue("@comment", newComment);
                cmd.Parameters.AddWithValue("@SiteId", site.ID.ToString("D"));
                cmd.Parameters.AddWithValue("@FileId", FileId.ToString("D"));
                cmd.Parameters.AddWithValue("@VersionId", version);
                conn.Open();
                int rows=cmd.ExecuteNonQuery();
                conn.Close();
                if (rows==1)
                    Console.WriteLine("CheckinComment was updated");
            }
            return 0;
        }
        private static int Usage()
        {
            Console.WriteLine("This program can be used to change the checkin comment of an old version of a file");
            Console.WriteLine(" {0} fileurl version new_comment", Environment.GetCommandLineArgs()[0]);
            return 1;
        }
    }
}