import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.SocketTimeoutException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.fasterxml.jackson.datatype.joda.JodaModule;
import com.espertech.esper.client.time.CurrentTimeEvent;

import javax.net.ssl.HttpsURLConnection;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;


public class OANDAReader implements TickStreamReader {
    final Logger log = LoggerFactory.getLogger(OANDAReader.class);
    ObjectMapper mapper;
    AccountInfo accountInfo;
	String[] instruments;


	public OANDAReader(AccountInfo accountInfo, String[] instruments) {
		this.accountInfo = accountInfo;
		this.instruments = instruments;

		mapper = new ObjectMapper();
		mapper.registerModule(new JodaModule());
	}

    public void run(TickProcessor processor) {
		readConnection(streamURL(), processor);
	}

	private String streamURL() {
		String type = accountInfo.isLiveAccount() ? "fxlive" : "fxpractice";
		String instrList = String.join(",", instruments);
		String query = "";
		try {
			query = String.format("instruments=%s", URLEncoder.encode(instrList, "UTF-8"));
		} catch (UnsupportedEncodingException e) {
			log.error("Creating stream URL", e);
		}

		return String.format("https://stream-%s.oanda.com/v3/accounts/%s/pricing/stream?%s",
							 type, accountInfo.accountID(), query);
	}

	private void readConnection(String urlStr, TickProcessor processor) {
		HttpsURLConnection httpConn = null;
		String line = null;
		try {
			URL url = new URL(urlStr);
			URLConnection urlConn = url.openConnection();
			if (!(urlConn instanceof HttpsURLConnection)) {
				throw new IOException ("URL is not an https URL");
			}
			httpConn = (HttpsURLConnection)urlConn;
			httpConn.setAllowUserInteraction(false);
			//httpConn.setInstanceFollowRedirects(true);
			httpConn.setRequestMethod("GET");
			//httpConn.setReadTimeout(50 * 1000);
			httpConn.setRequestProperty("Authorization", "Bearer 9a480f0b83e987f4015cf0846790c7d9-695ced635526744abd61bdf0e2ae8b71");
			BufferedReader is =
                new BufferedReader(new InputStreamReader(httpConn.getInputStream()));

			while ((line = is.readLine( )) != null) {
				processLine(line, processor);
			}
		} catch (IOException e) {
			log.error("Reading OANDA stream", e);
		} finally {
			httpConn.disconnect();
		}
	}

	private void processLine(String line, TickProcessor processor) {
		if (line.indexOf ("PRICE") > -1) {
			OANDATickEvent tick;
			try {
				tick = mapper.readValue(line, OANDATickEvent.class);
				processor.process(tick);
			} catch (JsonParseException | JsonMappingException e) {
				log.error("Parsing OANDA tick", e);
			} catch (IOException e) {
				log.error("Parsing OANDA tick", e);
			}
		} else if (line.indexOf ("HEARTBEAT") > -1) {
            try {
                OANDAHeartbeatEvent beat = mapper.readValue(line, OANDAHeartbeatEvent.class);
                processor.process(new CurrentTimeEvent(beat.getTime().getMillis()));
			} catch (IOException e) {
                log.error("Parsing OANDA heartbeat", e);
			}
		} else {
			log.warn("Unknown type: {}", line);
		}
	}
}