// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
using System.Collections.Generic;
 
namespace Microsoft.Extensions.FileSystemGlobbing.Internal.PathSegments
{
    public class WildcardPathSegment : IPathSegment
    {
        // It doesn't matter which StringComparison type is used in this MatchAll segment because
        // all comparing are skipped since there is no content in the segment.
        public static readonly WildcardPathSegment MatchAll = new WildcardPathSegment(
            string.Empty, new List<string>(), string.Empty, StringComparison.OrdinalIgnoreCase);
 
        private readonly StringComparison _comparisonType;
 
        public WildcardPathSegment(string beginsWith, List<string> contains, string endsWith, StringComparison comparisonType)
        {
            ThrowHelper.ThrowIfNull(beginsWith);
            ThrowHelper.ThrowIfNull(contains);
            ThrowHelper.ThrowIfNull(endsWith);
 
            _comparisonType = comparisonType switch
            {
                StringComparison.OrdinalIgnoreCase or StringComparison.Ordinal => comparisonType,
                _ => throw new InvalidOperationException(SR.Format(SR.StringComparisonTypeShouldBeOrdinal, comparisonType)),
            };
            BeginsWith = beginsWith;
            Contains = contains;
            EndsWith = endsWith;
        }
 
        public bool CanProduceStem { get { return true; } }
 
        public string BeginsWith { get; }
 
        public List<string> Contains { get; }
 
        public string EndsWith { get; }
 
        public bool Match(string value)
        {
            WildcardPathSegment wildcard = this;
 
            if (value.Length < wildcard.BeginsWith.Length + wildcard.EndsWith.Length)
            {
                return false;
            }
 
            if (!value.StartsWith(wildcard.BeginsWith, _comparisonType))
            {
                return false;
            }
 
            if (!value.EndsWith(wildcard.EndsWith, _comparisonType))
            {
                return false;
            }
 
            int beginRemaining = wildcard.BeginsWith.Length;
            int endRemaining = value.Length - wildcard.EndsWith.Length;
            for (int containsIndex = 0; containsIndex != wildcard.Contains.Count; ++containsIndex)
            {
                string containsValue = wildcard.Contains[containsIndex];
                int indexOf = value.IndexOf(
                    value: containsValue,
                    startIndex: beginRemaining,
                    count: endRemaining - beginRemaining,
                    comparisonType: _comparisonType);
                if (indexOf == -1)
                {
                    return false;
                }
 
                beginRemaining = indexOf + containsValue.Length;
            }
 
            return true;
        }
    }
}