using System;
using System.Data;
using Microsoft.SqlServer.Dts.Pipeline.Wrapper;
using Microsoft.SqlServer.Dts.Runtime.Wrapper;
using Microsoft.SqlServer.Dts.Pipeline;

[Microsoft.SqlServer.Dts.Pipeline.SSISScriptComponentEntryPointAttribute]
public class ScriptMain : UserComponent
{
    public override void ProcessInput(int InputID, PipelineBuffer Buffer)
    {
        var indexes = GetColumnIndexes(InputID);
       
        while (Buffer.NextRow())
        {
            foreach (var index in indexes)
            {
                if (!Buffer.IsNull(index))
                {
                    var date = Buffer.GetDateTime(index);
                    date = FixYear(date);
                    Buffer.SetDateTime(index, date);
                }
            }
        }
    }

    DateTime FixYear(DateTime input)
    {
        if (input.Year < 50)
            return input.AddYears(2000);

        if (input.Year < 100)
            return input.AddYears(1900);

        if (input.Year < 300)
            return input.AddYears(1800);

        return input;
    }
}