using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
namespace StyleCopContrib.Runner
{
///
/// A path utility class.
///
public static class PathUtility
{
#region Methods
///
/// Gets the common root path of the given path list.
///
/// The list of path.
/// The common root path.
public static string GetCommonRootPath(IEnumerable paths)
{
string[] commonPathParts = null;
int commonPartIndex = int.MaxValue;
foreach (string path in paths)
{
if (!Path.IsPathRooted(path))
{
throw new InvalidOperationException("Only fully qualified path are supported");
}
string[] pathParts = path.Split(Path.DirectorySeparatorChar);
if (commonPathParts == null)
{
commonPathParts = pathParts;
commonPartIndex = commonPathParts.Length;
}
else
{
int partIndex = 0;
while (partIndex < pathParts.Length && partIndex < commonPathParts.Length)
{
if (commonPathParts[partIndex].ToUpperInvariant() != pathParts[partIndex].ToUpperInvariant()) break;
partIndex++;
}
commonPartIndex = Math.Min(commonPartIndex, partIndex);
}
}
string commonPath;
if (commonPartIndex == 0)
{
commonPath = string.Empty;
}
else if (commonPartIndex == 1)
{
commonPath = string.Concat(commonPathParts[0], Path.DirectorySeparatorChar);
}
else
{
commonPath = string.Join(Path.DirectorySeparatorChar.ToString(), commonPathParts, 0, commonPartIndex);
}
return commonPath;
}
#endregion
}
}