using System;
using System.Globalization;

using IL2CPU.API.Attribs;

namespace Cosmos.System_Plugs.System.Globalization
{
    [Plug(Target = typeof(CompareInfo))]
    public static class CompareInfoImpl
    {
        public static void Ctor(CompareInfo aThis, CultureInfo aCulture)
        {
        }

        public static int CompareString(
            CompareInfo aThis, ReadOnlySpan<char> string1, ReadOnlySpan<char> string2, CompareOptions options) =>
            CompareOrdinalIgnoreCase(string1, string2);

        public static int CompareOrdinalIgnoreCase(ReadOnlySpan<char> string1, ReadOnlySpan<char> string2)
        {
            var minLength = Math.Min(string1.Length, string2.Length);

            for (int i = 0; i < minLength; i++)
            {
                if (string1[i] < string2[i])
                {
                    return -1;
                }

                if (string1[i] > string2[i])
                {
                    return 1;
                }
            }

            if (string1.Length < string2.Length)
            {
                return -1;
            }

            if (string1.Length > string2.Length)
            {
                return 1;
            }

            return 0;
        }

        public static bool StartsWith(
            CompareInfo aThis, string source, string prefix, CompareOptions options) =>
            StartsWith(aThis, source.AsSpan(), source.AsSpan(), options);

        public static bool StartsWith(
            CompareInfo aThis, ReadOnlySpan<char> source, ReadOnlySpan<char> prefix, CompareOptions options)
        {
            if (source.Length > prefix.Length)
            {
                return false;
            }

            for (int i = 0; i < prefix.Length; i++)
            {
                if (source[i] != prefix[i])
                {
                    return false;
                }
            }

            return true;
        }
    }
}