using System;
using System.Collections.Generic;

namespace LibMMD.Unity3D
{
    public enum MmdPhysicsMode
    {
        None,
        Unity,
        Bullet,
        MagicaCloth
    }

    /// <summary>Settings captured when a runtime MMD model instance is created.</summary>
    [Serializable]
    public sealed class MmdModelOptions
    {
        public MmdPhysicsMode Physics { get; set; } = MmdPhysicsMode.Bullet;
        public bool AnimationRigging { get; set; } = true;
        /// <summary>Reuse parsed model, Mesh, material, and texture resources between loads.</summary>
        public bool UseResourceCache { get; set; } = true;
        /// <summary>
        /// Maximum main-thread time spent on a batch of incremental model-build work before
        /// yielding to the next frame. Set to 0 to yield after every incremental operation.
        /// </summary>
        public float LoadingFrameBudgetMilliseconds { get; set; } = 2f;
        public MmdClothOptions Cloth { get; set; } = new MmdClothOptions();

        internal MmdModelOptions CopyAndValidate()
        {
            var cloth = Cloth ?? new MmdClothOptions();
            if (cloth.MaterialDominanceThreshold < 0f || cloth.MaterialDominanceThreshold > 1f)
                throw new ArgumentOutOfRangeException(
                    nameof(Cloth.MaterialDominanceThreshold));
            if (LoadingFrameBudgetMilliseconds < 0f || float.IsNaN(LoadingFrameBudgetMilliseconds) ||
                float.IsInfinity(LoadingFrameBudgetMilliseconds))
                throw new ArgumentOutOfRangeException(nameof(LoadingFrameBudgetMilliseconds));
            return new MmdModelOptions
            {
                Physics = Physics,
                AnimationRigging = AnimationRigging,
                UseResourceCache = UseResourceCache,
                LoadingFrameBudgetMilliseconds = LoadingFrameBudgetMilliseconds,
                Cloth = cloth.Copy()
            };
        }
    }

    /// <summary>Optional name overrides used by cloth-capable physics backends.</summary>
    [Serializable]
    public sealed class MmdClothOptions
    {
        public string[] IncludedBoneNames { get; set; } = Array.Empty<string>();
        public string[] ExcludedBoneNames { get; set; } = Array.Empty<string>();
        public string[] IncludedMaterialNames { get; set; } = Array.Empty<string>();
        public string[] ExcludedMaterialNames { get; set; } = Array.Empty<string>();
        public float MaterialDominanceThreshold { get; set; } = 0.1f;

        internal MmdClothOptions Copy()
        {
            return new MmdClothOptions
            {
                IncludedBoneNames = CopyArray(IncludedBoneNames),
                ExcludedBoneNames = CopyArray(ExcludedBoneNames),
                IncludedMaterialNames = CopyArray(IncludedMaterialNames),
                ExcludedMaterialNames = CopyArray(ExcludedMaterialNames),
                MaterialDominanceThreshold = MaterialDominanceThreshold
            };
        }

        private static string[] CopyArray(string[] values) =>
            values == null ? Array.Empty<string>() : (string[])values.Clone();
    }
}