// Copyright (c) .NET Foundation and contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System;
using System.Collections.Generic;
using ILLink.Shared;
using MultiValue = ILLink.Shared.DataFlow.ValueSet<ILLink.Shared.DataFlow.SingleValue>;

namespace Mono.Linker.Dataflow
{
    public class ValueNodeList : List<MultiValue>
    {
        public ValueNodeList()
        {
        }

        public ValueNodeList(int capacity)
            : base(capacity)
        {
        }

        public ValueNodeList(List<MultiValue> other)
            : base(other)
        {
        }

        public override int GetHashCode()
        {
            HashCode hashCode = default;
            foreach (var item in this)
                hashCode.Add(item.GetHashCode());
            return hashCode.ToHashCode();
        }

        public override bool Equals(object? other)
        {
            if (!(other is ValueNodeList otherList))
                return false;

            if (otherList.Count != Count)
                return false;

            for (int i = 0; i < Count; i++)
            {
                if (!otherList[i].Equals(this[i]))
                    return false;
            }
            return true;
        }
    }

    public struct ValueBasicBlockPair : IEquatable<ValueBasicBlockPair>
    {
        public ValueBasicBlockPair(MultiValue value, int basicBlockIndex)
        {
            Value = value;
            BasicBlockIndex = basicBlockIndex;
        }

        public MultiValue Value { get; }
        public int BasicBlockIndex { get; }

        public bool Equals(ValueBasicBlockPair other) => Value.Equals(other.Value) && BasicBlockIndex.Equals(other.BasicBlockIndex);

        public override bool Equals(object? obj) => obj is ValueBasicBlockPair other && Equals(other);

        public override int GetHashCode() => HashUtils.Combine(Value.GetHashCode(), BasicBlockIndex);

        public static bool operator ==(ValueBasicBlockPair left, ValueBasicBlockPair right) => left.Equals(right);
        public static bool operator !=(ValueBasicBlockPair left, ValueBasicBlockPair right) => !(left == right);
    }
}