using System;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Text;
using System.IO;
namespace PACNET
{
    /// <summary>MISC API</summary>
    public class MISC
    {
        //12.1. AnsiString
        /// <summary>
        /// This function can convert unicode string to ansi byte array.
        /// </summary>
        /// <param name="str">[in] A pointer to a buffer that stores unicode string.</param>
        /// <returns>Return ansi byte array.</returns>      
        public static byte[] AnsiString([In] string str)
        {
            Encoding ascii = Encoding.ASCII;
            Encoding unicode = Encoding.Unicode;

            byte[] unicodeBytes = unicode.GetBytes(str);
            byte[] temp = Encoding.Convert(unicode, ascii, unicodeBytes);
            byte[] ret = new byte[temp.Length + 1];

            temp.CopyTo(ret, 0);
            return ret;
        }

        //12.2. PAC_API void pac_AnsiToWideString(LPCSTR astr, LPTSTR wstr)

        //12.3. PAC_API void pac_DoEvents()
        /// <summary>
        /// When you run a Windows Form, it creates the new form, which then waits for events
        /// to handle. Each time the form handles an event, it processes all the code associated
        /// with that event. All other events wait in the queue. While your code handles the event,
        /// your application does not respond. If you call pac_DoEvents in your code, your
        /// application can handle the other events.
        /// </summary>
        [DllImport("PACSDK.dll", EntryPoint = "pac_DoEvents")]
        public static extern void DoEvents();

        //12.4. PAC_API void pac_WideStringToAnsi(const TCHAR *wstr, LPSTR astr)

        //12.5. WideString
        /// <summary>
        /// This function can convert ansi byte array to unicode string.
        /// </summary>
        /// <param name="CharStr">[in] A pointer to a buffer that stores ansi byte array.</param>
        /// <returns>Return unicode string.</returns>      
        public static string WideString(byte[] CharStr)
        {
            Encoding ascii = Encoding.ASCII;
            char[] asciiChars = new char[ascii.GetCharCount(CharStr, 0, CharStr.Length)];
            ascii.GetChars(CharStr, 0, CharStr.Length, asciiChars, 0);
            string asciiString = new string(asciiChars);
            return asciiString;
        }


        [DllImport("coredll.dll")]
        private static extern uint GetModuleFileName(IntPtr hModule, StringBuilder lpFileName, int nSize);

        /// <summary>get app path</summary>
        public static string GetAppPath()
        {
            string temp = Assembly.GetExecutingAssembly().GetName().CodeBase;
            return Path.GetDirectoryName(temp);
        }

        /// <summary>get current directory</summary>
        public static string GetCurrentDirectory()
        {
            string currDir = "";

            StringBuilder sb = new StringBuilder(256);

            if (GetModuleFileName(IntPtr.Zero, sb, sb.Capacity) > 0)
                currDir = sb.ToString();
            else
                return "";

            return Path.GetDirectoryName(currDir);
        }
    }
}