using System;

namespace Pilz.Configuration
{
    public class AutoSaveConfigurationManager : ConfigurationManager
    {
        private bool addedHandler = false;
        private bool enableAutoSave = false;
        private string _ConfigFilePath = string.Empty;
        private bool _AutoLoadConfigOnAccess = false;

        public string ConfigFilePath
        {
            get => _ConfigFilePath;
            set
            {
                _ConfigFilePath = value;
                if (AutoLoadConfigOnAccess)
                    Load();
            }
        }

        public bool AutoLoadConfigOnAccess
        {
            get => _AutoLoadConfigOnAccess;
            set
            {
                _AutoLoadConfigOnAccess = value;
                if (value)
                    Load();
            }
        }

        public bool AutoSaveConfigOnExit
        {
            get => enableAutoSave;
            set
            {
                if (enableAutoSave != value)
                {
                    enableAutoSave = value;
                    if (enableAutoSave)
                        AddAutoSaveHandler();
                    else
                        RemoveAutoSaveHandler();
                }
            }
        }

        private void AddAutoSaveHandler()
        {
            if (!addedHandler)
            {
                AppDomain.CurrentDomain.ProcessExit += AutoSaveSettingsOnExit;
                addedHandler = true;
            }
        }

        private void RemoveAutoSaveHandler()
        {
            AppDomain.CurrentDomain.ProcessExit -= AutoSaveSettingsOnExit;
            addedHandler = false;
        }

        private void AutoSaveSettingsOnExit(object sender, EventArgs e)
        {
            Save();
        }

        private void Save()
        {
            if (!string.IsNullOrEmpty(ConfigFilePath) && Configuration is not null)
                Configuration.WriteToFile(ConfigFilePath);
        }

        private void Load()
        {
            if (!string.IsNullOrEmpty(ConfigFilePath))
                Configuration.ReadFromFile(ConfigFilePath);
        }

        ~AutoSaveConfigurationManager()
        {
            RemoveAutoSaveHandler();
        }
    }
}