using System.Collections.Generic;

namespace zero.Core.Extensions
{
  public static class CharExtensions
  {
    private static Dictionary<char, char[]> accents { get; } = new Dictionary<char, char[]>()
    {
      { 'ä', new char[2] { 'a', 'e' } },
      { 'á', new char[1] { 'a' } },
      { 'à', new char[1] { 'a' } },
      { 'ó', new char[1] { 'o' } },
      { 'ò', new char[1] { 'o' } },
      { 'é', new char[1] { 'e' } },
      { 'è', new char[1] { 'e' } },
      { 'ú', new char[1] { 'u' } },
      { 'ù', new char[1] { 'u' } },
      { 'í', new char[1] { 'i' } },
      { 'ì', new char[1] { 'i' } },
      { 'ö', new char[2] { 'o', 'e' } },
      { 'ü', new char[2] { 'u', 'e' } },
      { 'ß', new char[2] { 's', 's' } },
      { '&', new char[1] { '+' } }
    };


    /// <summary>
    /// Check if a character is from a-z, A-Z or 0-9
    /// </summary>
    public static bool IsAZor09(this char value)
    {
      return (value >= 0x41 && value <= 0x5A) || (value >= 0x61 && value <= 0x7a) || (value >= 0x30 && value <= 0x39);
    }


    /// <summary>
    /// Check if a character is in ASCII range
    /// </summary>
    public static bool IsASCII(this char value)
    {
      return value < 128;
    }


    /// <summary>
    /// Replaces an accent or umlaut with the appropriate URL + file ready variant
    /// </summary>
    public static bool TryReplaceAccent(this char value, out char[] result)
    {
      if (!accents.ContainsKey(value))
      {
        result = null;
        return false;
      }

      result = accents[value];
      return true;
    }
  }
}