/*
 *                     GNU AFFERO GENERAL PUBLIC LICENSE
 *                       Version 3, 19 November 2007
 *  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 *  Everyone is permitted to copy and distribute verbatim copies
 *  of this license document, but changing it is not allowed.
 */

using System;
using System.ComponentModel;
using System.Text;

namespace UVtools.Core.Extensions;

public static class StringExtensions
{
    public static string RemoveFromEnd(this string input, int count)
    {
        return input.Remove(input.Length - count);
    }

    /// <summary>
    /// Upper the first character in a string
    /// </summary>
    /// <param name="input">Input string</param>
    /// <returns>Modified string with fist character upper</returns>
    public static string FirstCharToUpper(this string input)
    {
        return input switch
        {
            null => throw new ArgumentNullException(nameof(input)),
            "" => throw new ArgumentException($"{nameof(input)} cannot be empty", nameof(input)),
            _ => $"{char.ToUpper(input[0])}{input[1..]}"
        };
    }

    /// <summary>
    /// Repeat this string <paramref name="count"/> times
    /// </summary>
    /// <param name="str">String to repeat</param>
    /// <param name="count">Number of times to repeat</param>
    /// <returns><paramref name="str"/> repeated <paramref name="count"/> times</returns>
    public static string Repeat(this string str, int count)
        => count <= 0 ? string.Empty : new StringBuilder(str.Length * count).Insert(0, str, count).ToString();

    /// <summary>
    /// Converts a string into a target type
    /// </summary>
    /// <typeparam name="T">Target type to convert into</typeparam>
    /// <param name="input">Value</param>
    /// <returns>Converted value into target type</returns>
    public static T? Convert<T>(this string input)
    {
        var converter = TypeDescriptor.GetConverter(typeof(T));
        //Cast ConvertFromString(string text) : object to (T)
        var result = converter.ConvertFromString(input);
        if (result is null) return default;
        return (T) result;
    }
}