using DigitalData.Core.DTO;
using Microsoft.AspNetCore.Mvc;
using System.Text;

namespace DigitalData.Core.API
{
    /// <summary>
    /// Provides extension methods for controllers in ASP.NET Core applications.
    /// This class is designed to enhance the functionality of <see cref="Controller"/>, <see cref="ControllerBase"/>,
    /// and their related results such as <see cref="ViewResult"/>.
    /// </summary>
    public static class ControllerExtensions
    {
        /// <summary>
        /// Adds or updates a value in the ViewData dictionary of a ViewResult. This method supports fluent chaining, 
        /// enabling cleaner and more readable modifications to ViewData.
        /// </summary>
        /// <param name="viewResult">The ViewResult to which ViewData will be added or updated.</param>
        /// <param name="index">The key in the ViewData dictionary where the value will be stored.</param>
        /// <param name="value">The value to be stored in the ViewData dictionary.</param>
        /// <returns>The same ViewResult object with updated ViewData, allowing for additional chained operations.</returns>
        public static ViewResult WithData(this ViewResult viewResult, string index, object value)
        {
            viewResult.ViewData[index] = value;
            return viewResult;
        }

        /// <summary>
        /// Returns an ObjectResult representing an internal server error (status code 500) with optional exception and message details.
        /// </summary>
        /// <param name="controllerBase">The ControllerBase instance representing the controller.</param>
        /// <param name="ex">Optional. The exception that occurred, if any.</param>
        /// <param name="message">Optional. A custom error message to include in the response.</param>
        /// /// <param name="messageKey">Optional. A custom error message key to include in the response.</param>
        /// <returns>An ObjectResult representing an internal server error (status code 500).</returns>
        public static ObjectResult InnerServiceError(this ControllerBase controllerBase, Exception? ex = null, string? message = null)
        {
            var sb = new StringBuilder();
            if (ex is not null)
                sb.AppendLine(ex.Message);
            if (message is not null)
                sb.AppendLine(message);

            return controllerBase.StatusCode(500, sb.Length > 0 ? sb.ToString() : null);
        }

        /// <summary>
        /// Returns an ObjectResult representing an internal server error (status code 500) with optional exception and message details.
        /// </summary>
        /// <param name="controllerBase">The ControllerBase instance representing the controller.</param>
        /// <param name="result">Optional. A custom error resul to include in the response.</param>
        /// <returns>An ObjectResult representing an internal server error (status code 500).</returns>
        public static ObjectResult InnerServiceError(this ControllerBase controllerBase, Result? result = null) => controllerBase.StatusCode(500, result);
    }
}