// 
// CoreFoundation.cs
//  
// Author:
//       Michael Hutchinson <mhutchinson@novell.com>
//       Miguel de Icaza
// 
// Copyright (c) 2009 Novell, Inc. (http://www.novell.com)
// 
// 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;
using System.Runtime.InteropServices;

namespace MonoDevelop.MacInterop
{
    internal static class CoreFoundation
    {
        const string CFLib = "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation";
        const string LSLib = "/System/Library/Frameworks/ApplicationServices.framework/Versions/A/ApplicationServices";
        
        [DllImport (CFLib)]
        static extern IntPtr CFStringCreateWithCString (IntPtr alloc, string str, int encoding);
        
        public static IntPtr CreateString (string s)
        {
            // The magic value is "kCFStringENcodingUTF8"
            return CFStringCreateWithCString (IntPtr.Zero, s, 0x08000100);
        }
        
        [DllImport (CFLib, EntryPoint="CFRelease")]
        public static extern void Release (IntPtr cfRef);
        
        struct CFRange {
            public int Location, Length;
            public CFRange (int l, int len)
            {
                Location = l;
                Length = len;
            }
        }
        
        [DllImport (CFLib, CharSet=CharSet.Unicode)]
        extern static int CFStringGetLength (IntPtr handle);

        [DllImport (CFLib, CharSet=CharSet.Unicode)]
        extern static IntPtr CFStringGetCharactersPtr (IntPtr handle);
        
        [DllImport (CFLib, CharSet=CharSet.Unicode)]
        extern static IntPtr CFStringGetCharacters (IntPtr handle, CFRange range, IntPtr buffer);
        
        public static string FetchString (IntPtr handle)
        {
            if (handle == IntPtr.Zero)
                return null;
            
            string str;
            
            int l = CFStringGetLength (handle);
            IntPtr u = CFStringGetCharactersPtr (handle);
            IntPtr buffer = IntPtr.Zero;
            if (u == IntPtr.Zero){
                CFRange r = new CFRange (0, l);
                buffer = Marshal.AllocCoTaskMem (l * 2);
                CFStringGetCharacters (handle, r, buffer);
                u = buffer;
            }

            /*
            unsafe {
                str = new string ((char *) u, 0, l);
            }
            */
            str = Marshal.PtrToStringUni(u, l);

            if (buffer != IntPtr.Zero)
                Marshal.FreeCoTaskMem (buffer);
            
            return str;
        }
        
        public static string FSRefToString (ref FSRef fsref)
        {
            IntPtr url = IntPtr.Zero;
            IntPtr str = IntPtr.Zero;
            try {
                url = CFURLCreateFromFSRef (IntPtr.Zero, ref fsref);
                if (url == IntPtr.Zero)
                    return null;
                str = CFURLCopyFileSystemPath (url, CFUrlPathStyle.Posix);
                if (str == IntPtr.Zero)
                    return null;
                return FetchString (str);
            } finally {
                if (url != IntPtr.Zero)
                    Release (url);
                if (str != IntPtr.Zero)
                    Release (str);
            }
        }
        
        [DllImport (CFLib)]
        extern static IntPtr CFURLCreateFromFSRef (IntPtr allocator, ref FSRef fsref);
        
        [DllImport (CFLib)]
        extern static IntPtr CFURLCopyFileSystemPath (IntPtr urlRef, CFUrlPathStyle pathStyle);
        
        enum CFUrlPathStyle
        {
            Posix = 0,
            Hfs = 1,
            Windows = 2
        };
        
        [DllImport (CFLib)]
        extern static IntPtr CFURLCreateWithFileSystemPath (IntPtr allocator, IntPtr filePathString, 
            CFUrlPathStyle pathStyle, bool isDirectory);
        
        [DllImport (LSLib)]
        extern static IntPtr LSCopyApplicationURLsForURL (IntPtr urlRef, LSRolesMask roleMask); //CFArrayRef
        
        [DllImport (LSLib)]
        extern static int LSGetApplicationForURL (IntPtr url, LSRolesMask roleMask, IntPtr fsRefZero,
            ref IntPtr  appUrl);
        
        [DllImport (CFLib)]
        extern static int CFArrayGetCount (IntPtr theArray);
        
        [DllImport (CFLib)]
        extern static IntPtr CFArrayGetValueAtIndex (IntPtr theArray, int idx);
        
        [Flags]
        public enum LSRolesMask : uint
        {
            None = 0x00000001,
            Viewer = 0x00000002,
            Editor = 0x00000004,
            Shell = 0x00000008,
            All = 0xFFFFFFFF
        }
        
        static IntPtr CreatePathUrl (string path)
        {
            IntPtr str = IntPtr.Zero;
            IntPtr url = IntPtr.Zero;
            try {
                str = CreateString (path);
                if (str == IntPtr.Zero)
                    throw new Exception ("CreateString failed");
                url = CFURLCreateWithFileSystemPath (IntPtr.Zero, str, CFUrlPathStyle.Posix, false);
                if (url == IntPtr.Zero)
                    throw new Exception ("CFURLCreateWithFileSystemPath failed");
                return url;
            } finally {
                if (str != IntPtr.Zero)
                    Release (str);
            }
        }
        
        public static string UrlToPath (IntPtr url)
        {
            IntPtr str = IntPtr.Zero;
            try {
                str = CFURLCopyFileSystemPath (url, CFUrlPathStyle.Posix);
                return str == IntPtr.Zero? null : FetchString (str);
            } finally {
                if (str != IntPtr.Zero)
                    Release (str);
            }
        }
        
        public static string GetApplicationUrl (string filePath, LSRolesMask roles)
        {
            IntPtr url = IntPtr.Zero;
            try {
                url = CreatePathUrl (filePath);
                IntPtr appUrl = IntPtr.Zero;
                if (LSGetApplicationForURL (url, roles, IntPtr.Zero, ref appUrl) == 0 && appUrl != IntPtr.Zero)
                    return UrlToPath (appUrl);
                return null;
            } finally {
                if (url != IntPtr.Zero)
                    Release (url);
            }
        }
        
        public static string[] GetApplicationUrls (string filePath, LSRolesMask roles)
        {
            IntPtr url = IntPtr.Zero;
            IntPtr arr = IntPtr.Zero;
            try {
                url = CreatePathUrl (filePath);
                arr = LSCopyApplicationURLsForURL (url, roles);
                if (arr == IntPtr.Zero)
                    return new string[0];
                int count = CFArrayGetCount (arr);
                string[] values = new string [count];
                for (int i = 0; i < values.Length; i++ ) {
                    var u = CFArrayGetValueAtIndex (arr, i);
                    if (u != IntPtr.Zero)
                        values[i] = UrlToPath (u);
                }
                return values;
            } finally {
                if (url != IntPtr.Zero)
                    Release (url);
                if (arr != IntPtr.Zero)
                    Release (arr);
            }
        }
    }
}