retroactiune/Retroactiune.Core/Entities/Token.cs

using System;
using System.Runtime.CompilerServices;
using System.Text.Json.Serialization;
using Ardalis.GuardClauses;
using MongoDB.Bson;
using MongoDB.Bson.Serialization.Attributes;

namespace Retroactiune.Core.Entities
{
    /// <summary>
    /// Token represents a token.
    /// Token is used to authorize a <see cref="FeedbackReceiver"/> for the <see cref="Feedback"/>.
    /// </summary>
    public class Token
    {

        public Token()
        {
            Id = ObjectId.GenerateNewId().ToString();
            CreatedAt = DateTime.UtcNow;
        }
        
        [BsonId, JsonPropertyName("id")]
        [BsonRepresentation(BsonType.ObjectId)]
        public string Id { get; set; }

        [BsonRepresentation(BsonType.ObjectId), JsonPropertyName("feedback_receiver_id")]
        public string FeedbackReceiverId { get; set; }

        [JsonPropertyName("time_used")] public DateTime? TimeUsed { get; set; }

        [JsonPropertyName("created_at")] public DateTime CreatedAt { get; set; }

        [JsonPropertyName("expiry_time")] public DateTime? ExpiryTime { get; set; }

        public static bool operator ==(Token left, Token right)
        {
            return Equals(left, right);
        }

        public static bool operator !=(Token left, Token right)
        {
            return !Equals(left, right);
        }
        
        public override bool Equals(object obj)
        {
            if (!(obj is Token convertedObj))
            {
                return false;
            }

            return string.Equals(Id, convertedObj.Id) &&
                   string.Equals(FeedbackReceiverId, convertedObj.FeedbackReceiverId) &&
                   (CreatedAt - convertedObj.CreatedAt).Milliseconds == 0;
        }

        public override int GetHashCode()
        {
            return RuntimeHelpers.GetHashCode(this);
        }

        public bool IsValid()
        {
            var hasExpired = ExpiryTime != null && ExpiryTime <= DateTime.UtcNow;
            var isUsed = TimeUsed != null;
            return !(hasExpired || isUsed);
        }
        
        public bool IsValid(FeedbackReceiver feedbackReceiver)
        {
            Guard.Against.Null(feedbackReceiver, nameof(feedbackReceiver));
            var differentFeedbackReceiver = !FeedbackReceiverId.Equals(feedbackReceiver.Id);
            return !differentFeedbackReceiver && IsValid();
        }
    }
}