using MessengerApi.Configuration.Enums;
using MessengerApi.Configuration.Model.Persistence.Base;
using MessengerApi.Configuration.Parsers;
using MessengerApi.Configuration.Sources.Environment;
using Env = MessengerApi.Configuration.Constants.EnvironmentVariables;

namespace MessengerApi.Configuration.Model
{
    public class MessengerConfiguration
    {
        /// <summary>
        /// CORS origins.
        /// </summary>
        public string[] Origins { get; set; }

        /// <summary>
        /// List of proxies that are trusted to provide forwarding headers.
        /// </summary>
        public string[] Proxies { get; set; }

        /// <summary>
        /// Persistence layer configs (database).
        /// </summary>
        public PersistenceConfiguration PersistenceConfiguration { get; set; }

        /// <summary>
        /// Limits rate of user calls to not DoS the service.
        /// </summary>
        public int RateLimitPerMinute { get; set; }

        /// <summary>
        /// Message lifetime unless set differently in message body.
        /// </summary>
        public int DefaultMessageTimeToLiveInSeconds { get; set; }

        /// <summary>
        /// If true, messages are periodically wiped to free up space.
        /// </summary>
        public bool HousekeepingEnabled { get; set; }

        /// <summary>
        /// Messages older than value set will be deleted regardless of their delivery state.
        /// </summary>
        public int HousekeepingMessageAgeInMinutes { get; set; }

        /// <summary>
        /// Determines level of log messages displayed.
        /// </summary>
        public LoggingVerbosity Verbosity { get; set; }

        /// <summary>
        /// In addition to <see cref="HousekeepingMessageAgeInMinutes"/> messages of certain state can also be deleted, increasing storage efficiency.
        /// </summary>
        public HousekeepingMessageStates HousekeepingMessageState { get; set; }

        /// <summary>
        /// File containing all user credentials.
        /// </summary>
        public FileInfo UsersConfig { get; set; }

        public MessengerConfiguration() { }

        public MessengerConfiguration(string[] origins, PersistenceConfiguration persistenceConfiguration)
        {
            if (persistenceConfiguration == null)
            {
                throw new ArgumentNullException(nameof(persistenceConfiguration));
            }

            this.PersistenceConfiguration = persistenceConfiguration;
            this.UsersConfig = new FileInfo("./users.conf");
            this.Origins = origins ?? [];
            this.Proxies = [];
            this.RateLimitPerMinute = 120;
            this.DefaultMessageTimeToLiveInSeconds = 60;
            this.HousekeepingEnabled = true;
            this.HousekeepingMessageAgeInMinutes = 120;
            this.HousekeepingMessageState = HousekeepingMessageStates.None;
            this.Verbosity = LoggingVerbosity.Normal;
        }

        public MessengerConfiguration(IEnvironmentConfigurationSource config) : this(
            CorsParser.Parse(config.GetValue<string>(Env.CORS_ORIGINS)),
            EnvironmentPersistenceConfigurationParser.Parse(config))
        {
            Populate<string>(config, Env.PROXIES, x => this.Proxies = ProxiesParser.Parse(x));
            Populate<int>(config, Env.QUERY_RATE_PER_MINUTE, x => this.RateLimitPerMinute = x);
            Populate<int>(config, Env.DEFAULT_MESSAGE_TIME_TO_LIVE_IN_SECONDS, x => this.DefaultMessageTimeToLiveInSeconds = x);
            Populate<bool>(config, Env.HOUSEKEEPING_ENABLED, x => this.HousekeepingEnabled = x);
            Populate<int>(config, Env.HOUSEKEEPING_MESSAGE_AGE_IN_MINUTES, x => this.HousekeepingMessageAgeInMinutes = x);
            Populate<string>(config, Env.HOUSEKEEPING_MESSAGE_STATE, x => this.HousekeepingMessageState = HousekeepingMessageStateParser.Parse(x));
            Populate<string>(config, Env.LOGGING_VERBOSITY, x => this.Verbosity = LoggingVerbosityParser.Parse(x));
            Populate<string>(config, Env.USERSCONFIG_FILE_PATH, x => this.UsersConfig = new FileInfo(x));

            void Populate<T>(IEnvironmentConfigurationSource config, string key, Action<T> set)
            {
                if (config.HasKey(key))
                {
                    var value = config.GetValue<T>(key);
                    set(value);
                }
            }
        }
    }
}