// Copyright (c) Microsoft. All rights reserved.

using System;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using Microsoft.Extensions.AI;
using Microsoft.Extensions.VectorData.ProviderServices;

namespace Microsoft.SemanticKernel.Connectors.Qdrant;

internal class QdrantModelBuilder(bool hasNamedVectors) : CollectionModelBuilder(GetModelBuildOptions(hasNamedVectors))
{
    internal const string SupportedVectorTypes = "ReadOnlyMemory<float>, Embedding<float>, float[]";

    private static CollectionModelBuildingOptions GetModelBuildOptions(bool hasNamedVectors)
        => new()
        {
            RequiresAtLeastOneVector = !hasNamedVectors,
            SupportsMultipleVectors = hasNamedVectors,
        };

    protected override void ValidateKeyProperty(KeyPropertyModel keyProperty)
    {
        base.ValidateKeyProperty(keyProperty);

        var type = keyProperty.Type;

        if (type != typeof(ulong) && type != typeof(Guid))
        {
            throw new NotSupportedException(
                $"Property '{keyProperty.ModelName}' has unsupported type '{type.Name}'. Key properties must be either ulong or Guid.");
        }
    }

    protected override bool IsDataPropertyTypeValid(Type type, [NotNullWhen(false)] out string? supportedTypes)
    {
        supportedTypes = "string, int, long, double, float, bool, DateTime, DateTimeOffset,"
#if NET
            + " DateOnly,"
#endif
            + " or arrays/lists of these types";

        if (Nullable.GetUnderlyingType(type) is Type underlyingType)
        {
            type = underlyingType;
        }

        return IsValid(type)
            || (type.IsArray && IsValid(type.GetElementType()!))
            || (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(List<>) && IsValid(type.GenericTypeArguments[0]));

        static bool IsValid(Type type)
            => type == typeof(string) ||
                type == typeof(int) ||
                type == typeof(long) ||
                type == typeof(double) ||
                type == typeof(float) ||
                type == typeof(bool) ||
                type == typeof(DateTime) ||
#if NET
                type == typeof(DateOnly) ||
#endif
                type == typeof(DateTimeOffset);
    }

    protected override bool IsVectorPropertyTypeValid(Type type, [NotNullWhen(false)] out string? supportedTypes)
        => IsVectorPropertyTypeValidCore(type, out supportedTypes);

    internal static bool IsVectorPropertyTypeValidCore(Type type, [NotNullWhen(false)] out string? supportedTypes)
    {
        supportedTypes = "ReadOnlyMemory<float>, Embedding<float>, or float[]";

        return type == typeof(ReadOnlyMemory<float>)
            || type == typeof(ReadOnlyMemory<float>?)
            || type == typeof(Embedding<float>)
            || type == typeof(float[]);
    }
}
