using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;

namespace Macro_Correlation_Divergence_Arbitrage {

    public class YahooStockEngine {
        private const string BASE_URL = "http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20({0})&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys";

        public static List<Quote> Fetch(List<Quote> quotes) {
            string symbolList = String.Join("%2C", quotes.Select(w => "%22" + w.Symbol + "%22").ToArray());
            string url = string.Format(BASE_URL, symbolList);

            XDocument doc = XDocument.Load(url);
            Parse(ref quotes, doc);
            return quotes;
        }

        private static void Parse(ref List<Quote> quotes, XDocument doc) {
            XElement results = doc.Root.Element("results");

            foreach (Quote quote in quotes) {
                try {
                    XElement q = results.Elements("quote").First(w => w.Attribute("symbol").Value == quote.Symbol);

                    quote.Ask = GetDecimal(q.Element("Ask").Value);
                    quote.Bid = GetDecimal(q.Element("Bid").Value);
                    quote.AverageDailyVolume = GetDecimal(q.Element("AverageDailyVolume").Value);
                    quote.BookValue = GetDecimal(q.Element("BookValue").Value);
                    quote.Change = GetDecimal(q.Element("Change").Value);
                    quote.DividendShare = GetDecimal(q.Element("DividendShare").Value);
                    quote.LastTradeDate = GetDateTime(q.Element("LastTradeDate") + " " + q.Element("LastTradeTime").Value);
                    quote.EarningsShare = GetDecimal(q.Element("EarningsShare").Value);
                    quote.EpsEstimateCurrentYear = GetDecimal(q.Element("EPSEstimateCurrentYear").Value);
                    quote.EpsEstimateNextYear = GetDecimal(q.Element("EPSEstimateNextYear").Value);
                    quote.EpsEstimateNextQuarter = GetDecimal(q.Element("EPSEstimateNextQuarter").Value);
                    quote.DailyLow = GetDecimal(q.Element("DaysLow").Value);
                    quote.DailyHigh = GetDecimal(q.Element("DaysHigh").Value);
                    quote.YearlyLow = GetDecimal(q.Element("YearLow").Value);
                    quote.YearlyHigh = GetDecimal(q.Element("YearHigh").Value);
                    quote.MarketCapitalization = GetDecimal(q.Element("MarketCapitalization").Value);
                    quote.Ebitda = GetDecimal(q.Element("EBITDA").Value);
                    quote.ChangeFromYearLow = GetDecimal(q.Element("ChangeFromYearLow").Value);
                    quote.PercentChangeFromYearLow = GetDecimal(q.Element("PercentChangeFromYearLow").Value);
                    quote.ChangeFromYearHigh = GetDecimal(q.Element("ChangeFromYearHigh").Value);
                    quote.LastTradePrice = GetDecimal(q.Element("LastTradePriceOnly").Value);
                    quote.PercentChangeFromYearHigh = GetDecimal(q.Element("PercebtChangeFromYearHigh").Value); //missspelling in yahoo for field name
                    quote.FiftyDayMovingAverage = GetDecimal(q.Element("FiftydayMovingAverage").Value);
                    quote.TwoHunderedDayMovingAverage = GetDecimal(q.Element("TwoHundreddayMovingAverage").Value);
                    quote.ChangeFromTwoHundredDayMovingAverage = GetDecimal(q.Element("ChangeFromTwoHundreddayMovingAverage").Value);
                    quote.PercentChangeFromTwoHundredDayMovingAverage = GetDecimal(q.Element("PercentChangeFromTwoHundreddayMovingAverage").Value);
                    quote.PercentChangeFromFiftyDayMovingAverage = GetDecimal(q.Element("PercentChangeFromFiftydayMovingAverage").Value);
                    quote.Name = q.Element("Name").Value;
                    quote.Open = GetDecimal(q.Element("Open").Value);
                    quote.PreviousClose = GetDecimal(q.Element("PreviousClose").Value);
                    quote.ChangeInPercent = GetDecimal(q.Element("ChangeinPercent").Value);
                    quote.PriceSales = GetDecimal(q.Element("PriceSales").Value);
                    quote.PriceBook = GetDecimal(q.Element("PriceBook").Value);
                    quote.ExDividendDate = GetDateTime(q.Element("ExDividendDate").Value);
                    quote.PeRatio = GetDecimal(q.Element("PERatio").Value);
                    quote.DividendPayDate = GetDateTime(q.Element("DividendPayDate").Value);
                    quote.PegRatio = GetDecimal(q.Element("PEGRatio").Value);
                    quote.PriceEpsEstimateCurrentYear = GetDecimal(q.Element("PriceEPSEstimateCurrentYear").Value);
                    quote.PriceEpsEstimateNextYear = GetDecimal(q.Element("PriceEPSEstimateNextYear").Value);
                    quote.ShortRatio = GetDecimal(q.Element("ShortRatio").Value);
                    quote.OneYearPriceTarget = GetDecimal(q.Element("OneyrTargetPrice").Value);
                    quote.Volume = GetDecimal(q.Element("Volume").Value);
                    quote.StockExchange = q.Element("StockExchange").Value;

                    quote.LastUpdate = DateTime.Now;
                } catch {
                    //Program.SendEmail("Error on line 73 of Yahoo Stock Engine");
                }
                } 
        }

        private static decimal? GetDecimal(string input) {
            if (input == null) return null;

            input = input.Replace("%", "");

            decimal value;

            if (Decimal.TryParse(input, out value)) return value;
            return null;
        }

        private static DateTime? GetDateTime(string input) {
            if (input == null) return null;

            DateTime value;

            if (DateTime.TryParse(input, out value)) return value;
            return null;
        }
    }
}