using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace BlockIPAddr.ClassObj;

internal class ANSI
{
  /*
    ANSI Console Color Codes
      8 Colors Foreground
      The most basic terminals have a set of 8 different colors:

      Black: \u001b[30m
      Red: \u001b[31m
      Green: \u001b[32m
      Yellow: \u001b[33m
      Blue: \u001b[34m
      Magenta: \u001b[35m
      Cyan: \u001b[36m
      White: \u001b[37m
      Reset: \u001b[0m

      16 Colors Foreground
      Most terminals, apart from the basic set of 8 colors, also support the "bright" or "bold" colors. These have their own set of codes, mirroring the normal 
      colors, but with an additional ;1 in their codes:

      Bright Black: \u001b[30;1m
      Bright Red: \u001b[31;1m
      Bright Green: \u001b[32;1m
      Bright Yellow: \u001b[33;1m
      Bright Blue: \u001b[34;1m
      Bright Magenta: \u001b[35;1m
      Bright Cyan: \u001b[36;1m
      Bright White: \u001b[37;1m
      Reset: \u001b[0m

      Background Colors
      The Ansi escape codes let you set the color of the text-background the same way it lets you set the color of the foregrond. For example, the 8 background 
      colors correspond to the codes:

      Background Black: \u001b[40m
      Background Red: \u001b[41m
      Background Green: \u001b[42m
      Background Yellow: \u001b[43m
      Background Blue: \u001b[44m
      Background Magenta: \u001b[45m
      Background Cyan: \u001b[46m
      Background White: \u001b[47m
      With the bright versions being:

      Background Bright Black: \u001b[40;1m
      Background Bright Red: \u001b[41;1m
      Background Bright Green: \u001b[42;1m
      Background Bright Yellow: \u001b[43;1m
      Background Bright Blue: \u001b[44;1m
      Background Bright Magenta: \u001b[45;1m
      Background Bright Cyan: \u001b[46;1m
      Background Bright White: \u001b[47;1m

      Decorations
      Apart from colors, and background-colors, Ansi escape codes also allow decorations on the text:

      Bold: \u001b[1m
      Underline: \u001b[4m
      Reversed: \u001b[7m

      Source: https://www.lihaoyi.com/post/BuildyourownCommandLinewithANSIescapecodes.html
 */

  internal const string fgReset = "\u001b[0m";
  internal const string fgBrightBlack = "\u001b[30;1m";
  internal const string fgBrightRed = "\u001b[31;1m";
  internal const string fgBrightGreen = "\u001b[32;1m";
  internal const string fgBrightYellow = "\u001b[33;1m";
  internal const string fgBrightBlue = "\u001b[34;1m";
  internal const string fgBrightMagenta = "\u001b[35;1m";
  internal const string fgBrightCyan = "\u001b[36;1m";
  internal const string fgBrightWhite = "\u001b[37;1m";
  internal const string fgNormalBlack = "\u001b[30m";
  internal const string fgNormalRed = "\u001b[31m";
  internal const string fgNormalGreen = "\u001b[32m";
  internal const string fgNormalYellow = "\u001b[33m";
  internal const string fgNormalBlue = "\u001b[34m";
  internal const string fgNormalMagenta = "\u001b[35m";
  internal const string fgNormalCyan = "\u001b[36m";
  internal const string fgNormalWhite = "\u001b[37m";

  public static class ConsoleColorization
  {
    private const int STD_OUTPUT_HANDLE = -11;
    private const uint ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004;

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern IntPtr GetStdHandle(int nStdHandle);

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern bool GetConsoleMode(IntPtr hConsoleHandle, out uint lpMode);

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern bool SetConsoleMode(IntPtr hConsoleHandle, uint dwMode);

    public static void Initialize()
    {
      if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
      {
        EnableAnsiEscapeSequencesOnWindows();
        Console.OutputEncoding = System.Text.Encoding.UTF8;
      }
    } //Initialize

    private static void EnableAnsiEscapeSequencesOnWindows()
    {
      IntPtr handle = GetStdHandle(STD_OUTPUT_HANDLE);
      if (handle == IntPtr.Zero)
      {
        throw new Exception("Cannot get standard output handle");
      }

      if (!GetConsoleMode(handle, out uint mode))
      {
        throw new Exception("Cannot get console mode");
      }

      mode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
      if (!SetConsoleMode(handle, mode))
      {
        throw new Exception("Cannot set console mode");
      }
    } //EnableAnsiEscapeSequencesOnWindows
  } //ConsoleColor

}