using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace EventHoc
{
    public class EventSession
    {
        public IEventStorage Storage { get; private set; }

        public Guid SessionID { get; set; }
        public string SessionIdentifier { get; private set; }

        public DateTime SessionStart { get; private set; }
        public DateTime SessionEnd { get; private set; }

        private bool? _isOpen;
        private List<EventCache> _cachedEvents;

        public EventSession(string identifier = "")
        {
            SessionID = Guid.NewGuid();
            SessionIdentifier = identifier;
            _cachedEvents = new List<EventCache>();
        }

        public EventSession(IEventStorage storage)
        {
            Storage = storage;
        }

        public void Open()
        {
            if (_isOpen.HasValue)
            {
                logMessage("session already opened or closed");
                return;
            }

            SessionStart = DateTime.UtcNow;
            _isOpen = true;
        }

        public void Close()
        {
            if (_isOpen.HasValue)
            {
                logMessage("session already opened or closed");
                return;
            }

            SessionEnd = DateTime.UtcNow;
            _isOpen = false;
        }

        public void Flush()
        {
            //save events
        }

        public void Log(string eventName, Dictionary<string, string> attributes = null)
        {
            if(attributes == null)
                attributes = new Dictionary<string,string>();

            var e = new EventCache()
            {
                EventName = eventName,
                Attributes = attributes
            };

            _cachedEvents.Add(e);
        }

        private void logMessage(string message)
        {
            Debug.WriteLine("eventHOC - " + message);
        }
    }
}