using System;
using System.Collections.Generic;
using IBApi;

namespace Backend.MarketDataRequest
{
	public enum LiveMarketDataType
	{
		RealTime = 1,
		Frozen = 2,
		Delayed = 3,
		DelayedFrozen = 4
	}

	public sealed class LiveEquityRequest
	{
		public int RequestId { get; set; }
		public string Symbol { get; set; } = string.Empty;
		public string Exchange { get; set; } = "SMART";
		public string PrimaryExchange { get; set; } = "NASDAQ";
		public string Currency { get; set; } = "USD";

		/// <summary>
		/// Generic ticks string, e.g. "233,236"
		/// Leave empty for standard top-of-book.
		/// </summary>
		public string GenericTickList { get; set; } = string.Empty;

		public bool Snapshot { get; set; } = false;
		public bool RegulatorySnapshot { get; set; } = false;
		public LiveMarketDataType MarketDataType { get; set; } = LiveMarketDataType.RealTime;

		public void Send(IBGatewayControl gateway)
		{
			if (gateway == null)
			{
				throw new ArgumentNullException(nameof(gateway));
			}

			if (!gateway.IsConnected)
			{
				throw new InvalidOperationException("IB Gateway is not connected.");
			}

			if (string.IsNullOrWhiteSpace(Symbol))
			{
				throw new ArgumentException("Symbol cannot be empty.");
			}

			gateway.Client.reqMarketDataType((int)MarketDataType);

			var contract = BuildContract();

			gateway.Client.reqMktData(
				RequestId,
				contract,
				GenericTickList,
				Snapshot,
				RegulatorySnapshot,
				new List<TagValue>()
			);
		}

		public void Cancel(IBGatewayControl gateway)
		{
			if (gateway == null)
			{
				throw new ArgumentNullException(nameof(gateway));
			}

			if (!gateway.IsConnected)
			{
				throw new InvalidOperationException("IB Gateway is not connected.");
			}

			gateway.Client.cancelMktData(RequestId);
		}

		private Contract BuildContract()
		{
			return new Contract
			{
				Symbol = Symbol,
				SecType = "STK",
				Exchange = Exchange,
				PrimaryExch = PrimaryExchange,
				Currency = Currency
			};
		}
	}
}