package dk.thoerup.traininfoservice.banedk;



import java.net.URL;
import java.sql.SQLException;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;

import dk.thoerup.circuitbreaker.CircuitBreaker;
import dk.thoerup.circuitbreaker.CircuitBreakerManager;
import dk.thoerup.traininfoservice.StationDAO;
import dk.thoerup.traininfoservice.Statistics;

public class TimetableFetcher {

		
	Map<String, TimetableBean> cache; 
	Map<String, Integer> stationCache;

	StationDAO stationDao = new StationDAO();
	
	
	Logger logger = Logger.getLogger(TimetableFetcher.class.getName());
	
	private boolean useAzureSite;
	private int replyTimeout;
	
	public TimetableFetcher(boolean azureSite, int cacheTimeout, int replyTimeout) {
		useAzureSite = azureSite;
		this.replyTimeout = replyTimeout;
		
		cache = new TimeoutMap<String,TimetableBean>(cacheTimeout);
		stationCache = new TimeoutMap<String,Integer>( 3*60*60*1000 );
	}
	
	
	TimetableBean cachedLookupTimetable(String trainID, String type) throws Exception {
		String key = trainID+type;
		TimetableBean list = cache.get(key);
		
		if (list == null) {
			list = lookupTimetable(trainID,type);
			cache.put(key, list);
		} else {
			Statistics.getInstance().incrementTimetableCacheHits();
			logger.info("Timetable: Cache hit " + trainID); 
		}
		return list;
	}
	
	TimetableBean lookupTimetable(String trainID, String type) throws Exception {
		if (useAzureSite == true ){
			return lookupTimetableAzureSite(trainID, type);
			
		} else {
			return lookupTimetableWwwSite(trainID, type);
		}
	}
	
	int getStationId(String name) {
		Integer id = stationCache.get(name);
		
		if (id == null) {
			try {
				id = stationDao.getIdByName(name);
				stationCache.put(name, id);
			} catch (SQLException e) {
				logger.log(Level.SEVERE, "getStationId failed", e);
				id = -1;
			}
		} 

		return id;
	}

	TimetableBean lookupTimetableAzureSite(String trainID, String type) throws Exception {		
		TimetableBean timetableBean = new TimetableBean();
		

		String url = "http://trafikinfo.bane.dk/TrafikInformation/Ruteplan/" + trainID;			
		logger.fine("URL:" + url);
	    
	    JsoupInvocation wrapper = new JsoupInvocation( new URL(url) , replyTimeout);
	    CircuitBreaker breaker = CircuitBreakerManager.getManager().getCircuitBreaker("banedk");
	    
	    Document doc = (Document) breaker.invoke(wrapper);
	    	    
	    
	    boolean currentStation = false;
	    boolean currentStationSaved = false;
	    
	    Elements tables = doc.getElementsByClass("Rute");
	    
	    if (tables.size() == 1) {
	    	Element timetable = tables.get(0);
	    	Elements rows = timetable.getElementsByTag("tr");
	    	
	    	for (int i=0; i<rows.size(); i++) {
	    		if (i==0) //First row is column headers
	    			continue;
	    		
	    		
	    		Element row = rows.get(i);
	    		Elements fields = row.getElementsByTag("td");

	    		
	    		if (currentStationSaved == false && fields.get(0).attr("class").equalsIgnoreCase("Tidsstreg")) {
	    			currentStation = true;
	    			continue;
	    		}
	    		
	    		TimetableEntry entry = new TimetableEntry();
	    		
	    		String station = fields.get(0).text() ;
	    		if (station.equals("København"))
	    			station = "København H"; //correct inconsistency in naming
	    		
	    		entry.setStation( station );
	    		entry.setArrival( fields.get(1).text() );
	    		entry.setDeparture( fields.get(2).text() );
	    		
	    		boolean cancelled = fields.get(3).text().equalsIgnoreCase("aflyst");
	    		entry.setCancelled(cancelled);
	    		
	    		if (currentStation == true && currentStationSaved == false ) {
	    			entry.setCurrent(currentStation);
	    			currentStationSaved = true;
	    		}
	    		
	    		entry.setStationId( getStationId( station ));
	    		
	    		timetableBean.entries.add(entry);
	    	}
	    	
	    	//TODO: There is an off-by-one error in this cancelled parser thingie
	    	final String cancelledString = "Aflyst";
	    	for (int i=0;i<timetableBean.entries.size(); i++) { //handle cancelled labels
	    		final int lastIdx = (timetableBean.entries.size() - 1);
	    		
	    		TimetableEntry current = timetableBean.entries.get(i);
	    		if (current.isCancelled()) {
		    		if (i == 0) {
		    			current.setDeparture(cancelledString);
		    		} else if (i == lastIdx) {
		    			current.setArrival(cancelledString);
		    		} else if (i>0 && i<lastIdx) {
		    			TimetableEntry next = timetableBean.entries.get(i+1);
		    			TimetableEntry prev = timetableBean.entries.get(i-1);
		    			
		    			if (next.isCancelled())
		    				current.setDeparture(cancelledString);
		    			if (prev.isCancelled())
		    				current.setArrival(cancelledString);
		    		}
	    		}
	    	}
	    	
	    } else {
	    	logger.warning("No time table found, trainID=" + trainID + " type=" + type);
	    }
	    
		
		return timetableBean;
	}

	TimetableBean lookupTimetableWwwSite(String trainID, String type) throws Exception {		
		TimetableBean timetableBean = new TimetableBean();
		
		String url = "http://www.bane.dk/visRute.asp?W=" + type + "&TogNr=" + trainID + "&artikelId=4276";
		logger.fine("URL:" + url);

	    
	    JsoupInvocation wrapper = new JsoupInvocation( new URL(url) , replyTimeout);
	    CircuitBreaker breaker = CircuitBreakerManager.getManager().getCircuitBreaker("banedk");
	    
	    Document doc = (Document) breaker.invoke(wrapper);
	    	    
	    
	    boolean currentStation = false;
	    boolean currentStationSaved = false;
	    
	    Elements tables = doc.getElementsByClass("Rute");
	    
	    if (tables.size() == 1) {
	    	Element timetable = tables.get(0);
	    	Elements rows = timetable.getElementsByTag("tr");
	    	
	    	for (int i=0; i<rows.size(); i++) {
	    		if (i==0) //First row is column headers
	    			continue;
	    		
	    		
	    		Element row = rows.get(i);
	    		Elements fields = row.getElementsByTag("td");

	    		
	    		if (currentStationSaved == false && fields.get(0).attr("class").equalsIgnoreCase("Tidsstreg")) {
	    			currentStation = true;
	    			continue;
	    		}
	    		
	    		TimetableEntry entry = new TimetableEntry();
	    		
	    		String station = DepartureFetcher.cleanText( fields.get(0).text() ) ;
	    		if (station.equals("København"))
	    			station = "København H"; //correct inconsistency in naming
	    		
	    		String arrival = DepartureFetcher.cleanText( fields.get(1).text() );
	    		String departure = DepartureFetcher.cleanText( fields.get(2).text() );
	    		
	    		entry.setStation( station );
	    		entry.setArrival( arrival );
	    		entry.setDeparture( departure );
    		
	    		
	    		if (currentStation == true && currentStationSaved == false ) {
	    			entry.setCurrent(currentStation);
	    			currentStationSaved = true;
	    		}
	    		
	    		entry.setStationId( getStationId( station ));
	    		
	    		timetableBean.entries.add(entry);
	    	}	    	
	    	
	    } else {
	    	logger.warning("No time table found, trainID=" + trainID + " type=" + type);
	    }
	    
		
		return timetableBean;
	}	
	
}