//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//     file="CapacityFixedList.cs"
//     Project: StgSharp
//     AuthorGroup: Nitload Space
//     Copyright (c) Nitload Space. All rights reserved.
//     
//     Permission is hereby granted, free of charge, to any person 
//     obtaining a copy of this software and associated documentation 
//     files (the “Software”), to deal in the Software without restriction, 
//     including without limitation the rights to use, copy, modify, merge,
//     publish, distribute, sublicense, and/or sell copies of the Software, 
//     and to permit persons to whom the Software is furnished to do so, 
//     subject to the following conditions:
//     
//     The above copyright notice and 
//     this permission notice shall be included in all copies 
//     or substantial portions of the Software.
//     
//     THE SOFTWARE IS PROVIDED “AS IS”, 
//     WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
//     INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
//     FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
//     IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
//     DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
//     ARISING FROM, OUT OF OR IN CONNECTION WITH 
//     THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//     
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
using System;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Text;

namespace StgSharp.Commom.Collections
{
    public static class CapacityFixedListBuilder
    {
        internal static CapacityFixedList<T> Create<T>(ReadOnlySpan<T> values)
        {
            return new CapacityFixedList<T>(values);
        }
    }

    [CollectionBuilder(typeof(CapacityFixedListBuilder),nameof(CapacityFixedListBuilder.Create))]
    public class CapacityFixedList<T> : IList<T>
    {

        private T[] _values;
        private int capacity, _index;

        public CapacityFixedList( int size )
        {
            _values = new T[size];
        }

        public CapacityFixedList(ReadOnlySpan<T> values)
        {
            _values = values.ToArray();
        }

        public T this[ int index ]
        {
            get => index < _index ?
                    _values[ index ] : throw new ArgumentOutOfRangeException(
                        nameof( index ) );
            set
            {
                if( index < _index ) {
                    _values[ index ] = value;
                } else {
                    throw new ArgumentOutOfRangeException( nameof( index ) );
                }
            }
        }

        public bool IsReadOnly => false;

        public int Count => _index + 1;

        public void Add( T item )
        {
            if( _index < capacity - 1 ) {
                _index++;
                this[ _index ] = item;
            }
        }

        public void Clear()
        {
            _values = new T[capacity];
            _index = 0;
        }

        public bool Contains( T item )
        {
            for( int i = 0; i <= _index; i++ ) {
                if( item.Equals( _values[ i ] ) ) {
                    return true;
                }
            }
            return false;
        }

        public void CopyTo( T[] array, int arrayIndex )
        {
            _values.CopyTo( array, arrayIndex );
        }

        public IEnumerator<T> GetEnumerator()
        {
            for( int i = 0; i <= _index; i++ ) {
                yield return _values[ i ];
            }
        }

        public int IndexOf( T item )
        {
            T v;
            for( int i = 0; i <= _index; i++ ) {
                if( ( v = _values[ i ] ) != null && v.Equals( item ) ) {
                    return i;
                }
            }
            return -1;
        }

        public bool Remove( T item )
        {
            T v;
            for( int i = 0; i <= _index; i++ ) {
                if( ( v = _values[ i ] ) != null && v.Equals( item ) ) {
                    _values[ i ] = _values[ _index ];
                    _index--;
                    return true;
                }
            }
            return false;
        }

        public void RemoveAll( Predicate<T> predicate )
        {
            for( int i = _index; i > 0; i-- ) {
                if( predicate( _values[ i ] ) ) {
                    _values[ i ] = _values[ _index ];
                    _index--;
                }
            }
        }

        public void RemoveAt( int index )
        {
            if( index <= _index ) {
                _values[ index ] = _values[ _index ];
                _index--;
            }
        }

        public void Resize( int newSize )
        {
            Array.Resize( ref _values, newSize );
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            yield return GetEnumerator();
        }

        void IList<T>.Insert( int index, T item )
        {
            throw new NotSupportedException();
        }

    }//------------------------------------- End of Class ------------------------------------------
}