// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Reflection;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http.Metadata;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
 
namespace Microsoft.AspNetCore.Http.HttpResults;
 
/// <summary>
/// An <see cref="IResult"/> that on execution will write an object to the response
/// with Unprocessable Entity (422) status code.
/// </summary>
/// <typeparam name="TValue">The type of object that will be JSON serialized to the response body.</typeparam>
public sealed class UnprocessableEntity<TValue> : IResult, IEndpointMetadataProvider, IStatusCodeHttpResult, IValueHttpResult, IValueHttpResult<TValue>
{
    /// <summary>
    /// Initializes a new instance of the <see cref="UnprocessableEntity"/> class with the values
    /// provided.
    /// </summary>
    /// <param name="value">The value to format in the entity body.</param>
    internal UnprocessableEntity(TValue? value)
    {
        Value = value;
        HttpResultsHelper.ApplyProblemDetailsDefaultsIfNeeded(Value, StatusCode);
    }
 
    /// <summary>
    /// Gets the object result.
    /// </summary>
    public TValue? Value { get; }
 
    object? IValueHttpResult.Value => Value;
 
    /// <summary>
    /// Gets the HTTP status code: <see cref="StatusCodes.Status422UnprocessableEntity"/>
    /// </summary>
    public int StatusCode => StatusCodes.Status422UnprocessableEntity;
 
    int? IStatusCodeHttpResult.StatusCode => StatusCode;
 
    /// <inheritdoc />
    public Task ExecuteAsync(HttpContext httpContext)
    {
        ArgumentNullException.ThrowIfNull(httpContext);
 
        // Creating the logger with a string to preserve the category after the refactoring.
        var loggerFactory = httpContext.RequestServices.GetRequiredService<ILoggerFactory>();
        var logger = loggerFactory.CreateLogger("Microsoft.AspNetCore.Http.Result.UnprocessableEntityObjectResult");
 
        HttpResultsHelper.Log.WritingResultAsStatusCode(logger, StatusCode);
        httpContext.Response.StatusCode = StatusCode;
 
        return HttpResultsHelper.WriteResultAsJsonAsync(
                httpContext,
                logger: logger,
                Value);
    }
 
    /// <inheritdoc/>
    static void IEndpointMetadataProvider.PopulateMetadata(MethodInfo method, EndpointBuilder builder)
    {
        ArgumentNullException.ThrowIfNull(method);
        ArgumentNullException.ThrowIfNull(builder);
 
        builder.Metadata.Add(new ProducesResponseTypeMetadata(StatusCodes.Status422UnprocessableEntity, typeof(TValue), new[] { "application/json" }));
    }
}