using System;
using System.Linq;

using FrostFS.Netmap;
using FrostFS.SDK.Client;

namespace FrostFS.SDK;

public struct FrostFsPlacementPolicy(bool unique, params FrostFsReplica[] replicas)
    : IEquatable<FrostFsPlacementPolicy>
{
    private PlacementPolicy policy;

    public FrostFsReplica[] Replicas { get; private set; } = replicas;
    public bool Unique { get; private set; } = unique;

    public override readonly bool Equals(object obj)
    {
        if (obj is null)
            return false;

        var other = (FrostFsPlacementPolicy)obj;

        return Equals(other);
    }

    public PlacementPolicy GetPolicy()
    {
        if (policy == null)
        {
            policy = new PlacementPolicy
            {
                Filters = { },
                Selectors = { },
                Replicas = { },
                Unique = Unique
            };

            foreach (var replica in Replicas)
            {
                policy.Replicas.Add(replica.ToMessage());
            }
        }

        return policy;
    }

    //public static FrostFsPlacementPolicy ToModel(placementPolicy)
    //{
    //    return new FrostFsPlacementPolicy(
    //        placementPolicy.Unique,
    //        placementPolicy.Replicas.Select(replica => replica.ToModel()).ToArray()
    //    );
    //}


    public override readonly int GetHashCode()
    {
        return Unique ? 17 : 0 + Replicas.GetHashCode();
    }

    public static bool operator ==(FrostFsPlacementPolicy left, FrostFsPlacementPolicy right)
    {
        return left.Equals(right);
    }

    public static bool operator !=(FrostFsPlacementPolicy left, FrostFsPlacementPolicy right)
    {
        return !(left == right);
    }

    public readonly bool Equals(FrostFsPlacementPolicy other)
    {
        var notEqual = Unique != other.Unique
         || Replicas.Length != other.Replicas.Length;

        if (notEqual)
            return false;

        foreach (var replica in Replicas)
        {
            if (!other.Replicas.Any(r => r.Equals(replica)))
                return false;
        }

        return true;
    }
}