#region Using Directives

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;

#endregion Using Directives


namespace ScintillaNET
{
    public static class Utilities
    {
        #region Methods

        /// <summary>
        ///     Returns an HTML #XXXXXX format for a color. Unlike the ColorTranslator class it
        ///     never returns named colors.
        /// </summary>
        public static string ColorToHtml(Color c)
        {
            return "#" + c.R.ToString("X2", null) + c.G.ToString("X2", null) + c.B.ToString("X2", null);
        }


        public static int ColorToRgb(Color c)
        {
            return c.R + (c.G << 8) + (c.B << 16);
        }


        public static Keys GetKeys(char c)
        {
            switch (c)
            {
                case '/':
                    return Keys.Oem2;
                case '`':
                    return Keys.Oem3;
                case '[':
                    return Keys.Oem4;
                case '\\':
                    return Keys.Oem5;
                case ']':
                    return Keys.Oem6;
                case '-':
                    return (Keys)189;

            }

            return (Keys)Enum.Parse(typeof(Keys), c.ToString(), true);
        }


        public static Keys GetKeys(string s)
        {
            switch (s)
            {
                case "/":
                    return Keys.Oem2;
                case "`":
                    return Keys.Oem3;
                case "[":
                    return Keys.Oem4;
                case "\\":
                    return Keys.Oem5;
                case "]":
                    return Keys.Oem6;
                case "-":
                    return (Keys)189;
            }

            return (Keys)Enum.Parse(typeof(Keys), s, true);
        }


        public static uint GetMarkerMask(IEnumerable<int> markers)
        {
            uint mask = 0;
            foreach (int i in markers)
                mask |= ((uint)1) << i;
            return mask;
        }


        public static uint GetMarkerMask(IEnumerable<Marker> markers)
        {
            uint mask = 0;
            foreach (Marker m in markers)
                mask |= m.Mask;
            return mask;
        }


        public static byte[] GetZeroTerminatedBytes(string text, Encoding encoding)
        {
            if (string.IsNullOrEmpty(text))
                return new byte[] { 0 };

            // This should be a little less wasteful than simply appending
            // a null terminator to the string and then converting it
            int byteCount = encoding.GetByteCount(text);
            byte[] buffer = new byte[byteCount + 1];

            unsafe
            {
                fixed (byte* bp = buffer)
                fixed (char* ch = text)
                {
                    int count = encoding.GetBytes(ch, text.Length, bp, byteCount);
                    Debug.Assert(count == byteCount);
                }
            }

            // And the end cap...
            buffer[buffer.Length - 1] = 0;
            return buffer;
        }


        public static unsafe string IntPtrToString(Encoding encoding, IntPtr ptr)
        {
            if (ptr == IntPtr.Zero)
                return null;

            // Find the length of the null terminated bytes
            int length = 0;
            while (*((byte*)ptr + length) != (byte)0)
                length++;

            return IntPtrToString(encoding, ptr, length);
        }



        /// <summary>
        ///     Marshals an IntPtr pointing to un unmanaged byte[] to a .NET String using the given Encoding.
        /// </summary>
        /// <remarks>
        ///     I'd love to have this as en extension method but ScintillaNET's probably going to be 2.0 for a long
        ///     time to come. There's nothing really compelling in later versions that applies to ScintillaNET that
        ///     can't be done with a 2.0 construct (extension methods, linq, etc)
        /// </remarks>
        public static string IntPtrToString(Encoding encoding, IntPtr ptr, int length)
        {
            //	null pointer = null string
            if (ptr == IntPtr.Zero)
                return null;

            //	0 _length string = string.Empty
            if (length == 0)
                return string.Empty;

            byte[] buff = new byte[length];
            Marshal.Copy(ptr, buff, 0, length);

            //	We don't want to carry over the Trailing null
            if (buff[buff.Length - 1] == 0)
                length--;

            return encoding.GetString(buff, 0, length);
        }


        public static Color RgbToColor(int color)
        {
            return Color.FromArgb(color & 0x0000ff, (color & 0x00ff00) >> 8, (color & 0xff0000) >> 16);
        }


        public static int SignedHiWord(IntPtr hiWord)
        {
            return (short)(((int)(long)hiWord >> 0x10) & 0xffff);
        }


        public static int SignedLoWord(IntPtr loWord)
        {
            return (short)((int)(long)loWord & 0xffff);
        }

        #endregion Methods
    }
}