//
// System.Web.VirtualPath.cs
//
// Authors:
//   Marek Habersack (mhabersack@novell.com)
//
// (C) 2008-2009 Novell, Inc
//

//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.IO;
using System.Web.Compilation;
using System.Web.Util;

namespace System.Web
{
	internal class VirtualPath : IDisposable
	{
		string _absolute;
		string _appRelative;
		string _appRelativeNotRooted;
		string _extension;
		string _directory;
		string _directoryNoNormalize;
		string _currentRequestDirectory;
		string _physicalPath;
		
		public bool IsAbsolute {
			get;
			private set;
		}

		public bool IsFake {
			get;
			private set;
		}
		
		public bool IsRooted {
			get;
			private set;
		}

		public bool IsAppRelative {
			get;
			private set;
		}
		
		public string Original {
			get;
			private set;
		}

		public string Absolute {
			get {
				if (IsAbsolute)
					return Original;

				if (_absolute == null) {
					string original = Original;
					
					if (!VirtualPathUtility.IsRooted (original))
						_absolute = MakeRooted (original);
					else
						_absolute = original;

					if (VirtualPathUtility.IsAppRelative (_absolute))
						_absolute = VirtualPathUtility.ToAbsolute (_absolute);
				}

				return _absolute;
			}
		}

		public string AppRelative {
			get {
				if (IsAppRelative)
					return Original;

				if (_appRelative == null) {
					string original = Original;
					
					if (!VirtualPathUtility.IsRooted (original))
						_appRelative = MakeRooted (original);
					else
						_appRelative = original;
					
					if (VirtualPathUtility.IsAbsolute (_appRelative))
						_appRelative = VirtualPathUtility.ToAppRelative (_appRelative);
				}

				return _appRelative;
			}
		}
		
		public string AppRelativeNotRooted {
			get {
				if (_appRelativeNotRooted == null)
					_appRelativeNotRooted = AppRelative.Substring (2);

				return _appRelativeNotRooted;
			}
		}

		public string Extension {
			get {
				if (_extension == null)
					_extension = VirtualPathUtility.GetExtension (Original);

				return _extension;
			}
		}

		public string Directory {
			get {
				if (_directory == null)
					_directory = VirtualPathUtility.GetDirectory (Absolute);

				return _directory;
			}
		}

		public string DirectoryNoNormalize {
			get {
				if (_directoryNoNormalize == null)
					_directoryNoNormalize = VirtualPathUtility.GetDirectory (Absolute, false);
				
				return _directoryNoNormalize;
			}
		}
		
		public string CurrentRequestDirectory {
			get {
				if (_currentRequestDirectory != null)
					return _currentRequestDirectory;

				HttpContext ctx = HttpContext.Current;
				HttpRequest req = ctx != null ? ctx.Request : null;
				if (req != null)
					return VirtualPathUtility.GetDirectory (req.CurrentExecutionFilePath);

				return null;
			}

			set { _currentRequestDirectory = value; }
		}

		public string PhysicalPath {
			get {
				if (_physicalPath != null)
					return _physicalPath;

				HttpContext ctx = HttpContext.Current;
				HttpRequest req = ctx != null ? ctx.Request : null;
				if (req != null)
					_physicalPath = req.MapPath (Absolute);
				else
					return null;
				
				return _physicalPath;
			}
		}
				
		public VirtualPath (string vpath)
			: this (vpath, null, false)
		{
		}
		
		public VirtualPath (string vpath, string baseVirtualDir)
			: this (vpath, null, false)
		{
			CurrentRequestDirectory = baseVirtualDir;
		}

		public VirtualPath (string vpath, string physicalPath, bool isFake)
		{
			IsRooted = VirtualPathUtility.IsRooted (vpath);
			IsAbsolute = VirtualPathUtility.IsAbsolute (vpath);
			IsAppRelative = VirtualPathUtility.IsAppRelative (vpath);
			
			if (isFake) {
				if (String.IsNullOrEmpty (physicalPath))
					throw new ArgumentException ("physicalPath");
				
				_physicalPath = physicalPath;
				Original = "~/" + Path.GetFileName (_physicalPath);
				IsFake = true;
			} else {
				Original = vpath;
				IsFake = false;
			}
		}
		
		public bool StartsWith (string s)
		{
			return StrUtils.StartsWith (Original, s);
		}

		// Assumes 'original' is NOT rooted
		string MakeRooted (string original)
		{
			string reqdir = CurrentRequestDirectory;
			
			if (!String.IsNullOrEmpty (reqdir))
				return VirtualPathUtility.Combine (reqdir, original);
			else
				return VirtualPathUtility.Combine (HttpRuntime.AppDomainAppVirtualPath, original);
		}

		public void Dispose ()
		{
			_absolute = null;
			_appRelative = null;
			_appRelativeNotRooted = null;
			_extension = null;
			_directory = null;
		}
		
		public override string ToString ()
		{
			string ret = Original;

			if (String.IsNullOrEmpty (ret))
				return GetType ().ToString ();

			if (IsFake)
				ret += " [fake: " + PhysicalPath + "]";
			
			return ret;
		}

		public static VirtualPath PhysicalToVirtual (string physical_path)
		{
			if (String.IsNullOrEmpty (physical_path))
				return null;
			
			string appPhysicalPath = HttpRuntime.AppDomainAppPath;
			if (!StrUtils.StartsWith (physical_path, appPhysicalPath))
				return null;

			string vp = physical_path.Substring (appPhysicalPath.Length - 1);
			if (vp [0] != '/')
				return null;
			
			return new VirtualPath (vp);
		}
	}
}