// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.AspNetCore.Routing;
using Microsoft.Extensions.Internal;

namespace Microsoft.AspNetCore.Mvc.ApplicationModels
{
    /// <summary>
    /// A model for configuring controllers.
    /// </summary>
    [DebuggerDisplay("{DisplayName}")]
    public class ControllerModel : ICommonModel, IFilterModel, IApiExplorerModel
    {
        /// <summary>
        /// Initializes a new instance of <see cref="ControllerModel"/>.
        /// </summary>
        /// <param name="controllerType">The type of the controller.</param>
        /// <param name="attributes">The attributes.</param>
        public ControllerModel(
            TypeInfo controllerType,
            IReadOnlyList<object> attributes)
        {
            if (controllerType == null)
            {
                throw new ArgumentNullException(nameof(controllerType));
            }

            if (attributes == null)
            {
                throw new ArgumentNullException(nameof(attributes));
            }

            ControllerType = controllerType;

            Actions = new List<ActionModel>();
            ApiExplorer = new ApiExplorerModel();
            Attributes = new List<object>(attributes);
            ControllerProperties = new List<PropertyModel>();
            Filters = new List<IFilterMetadata>();
            Properties = new Dictionary<object, object?>();
            RouteValues = new Dictionary<string, string?>(StringComparer.OrdinalIgnoreCase);
            Selectors = new List<SelectorModel>();
        }

        /// <summary>
        /// Initializes a new instance of <see cref="ControllerModel"/>.
        /// </summary>
        /// <param name="other">The other controller model.</param>
        public ControllerModel(ControllerModel other)
        {
            if (other == null)
            {
                throw new ArgumentNullException(nameof(other));
            }

            ControllerName = other.ControllerName;
            ControllerType = other.ControllerType;

            // Still part of the same application
            Application = other.Application;

            // These are just metadata, safe to create new collections
            Attributes = new List<object>(other.Attributes);
            Filters = new List<IFilterMetadata>(other.Filters);
            RouteValues = new Dictionary<string, string?>(other.RouteValues, StringComparer.OrdinalIgnoreCase);
            Properties = new Dictionary<object, object?>(other.Properties);

            // Make a deep copy of other 'model' types.
            Actions = new List<ActionModel>(other.Actions.Select(a => new ActionModel(a) { Controller = this }));
            ApiExplorer = new ApiExplorerModel(other.ApiExplorer);
            ControllerProperties =
                new List<PropertyModel>(other.ControllerProperties.Select(p => new PropertyModel(p) { Controller = this }));
            Selectors = new List<SelectorModel>(other.Selectors.Select(s => new SelectorModel(s)));
        }

        /// <summary>
        /// The actions on this controller.
        /// </summary>
        public IList<ActionModel> Actions { get; }

        /// <summary>
        /// Gets or sets the <see cref="ApiExplorerModel"/> for this controller.
        /// </summary>
        /// <remarks>
        /// <see cref="ControllerModel.ApiExplorer"/> allows configuration of settings for ApiExplorer
        /// which apply to all actions in the controller unless overridden by <see cref="ActionModel.ApiExplorer"/>.
        ///
        /// Settings applied by <see cref="ControllerModel.ApiExplorer"/> override settings from
        /// <see cref="ApplicationModel.ApiExplorer"/>.
        /// </remarks>
        public ApiExplorerModel ApiExplorer { get; set; }

        /// <summary>
        /// Gets or sets the <see cref="ApplicationModel"/> of this controller.
        /// </summary>
        public ApplicationModel? Application { get; set; }

        /// <summary>
        /// The attributes of this controller.
        /// </summary>
        public IReadOnlyList<object> Attributes { get; }

        MemberInfo ICommonModel.MemberInfo => ControllerType;

        string ICommonModel.Name => ControllerName;

        /// <summary>
        /// Gets or sets the name of this controller.
        /// </summary>
        public string ControllerName { get; set; } = default!;

        /// <summary>
        /// The type of this controller.
        /// </summary>
        public TypeInfo ControllerType { get; }

        /// <summary>
        /// The properties of this controller.
        /// </summary>
        public IList<PropertyModel> ControllerProperties { get; }

        /// <summary>
        /// The filter metadata of this controller.
        /// </summary>
        public IList<IFilterMetadata> Filters { get; }

        /// <summary>
        /// Gets a collection of route values that must be present in the
        /// <see cref="RouteData.Values"/> for the corresponding action to be selected.
        /// </summary>
        /// <remarks>
        /// Entries in <see cref="RouteValues"/> can be overridden by entries in
        /// <see cref="ActionModel.RouteValues"/>.
        /// </remarks>
        public IDictionary<string, string?> RouteValues { get; }

        /// <summary>
        /// Gets a set of properties associated with the controller.
        /// These properties will be copied to <see cref="Abstractions.ActionDescriptor.Properties"/>.
        /// </summary>
        /// <remarks>
        /// Entries will take precedence over entries with the same key
        /// in <see cref="ApplicationModel.Properties"/>.
        /// </remarks>
        public IDictionary<object, object?> Properties { get; }

        /// <summary>
        /// The selector models of this controller.
        /// </summary>
        public IList<SelectorModel> Selectors { get; }

        /// <summary>
        /// The DisplayName of this controller.
        /// </summary>
        public string DisplayName
        {
            get
            {
                var controllerType = TypeNameHelper.GetTypeDisplayName(ControllerType);
                var controllerAssembly = ControllerType.Assembly.GetName().Name;
                return $"{controllerType} ({controllerAssembly})";
            }
        }
    }
}
