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 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 {
    AccountInfo accountInfo;
	String[] instruments;


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

    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) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return String.format("https://stream-%s.oanda.com/v3/accounts/%s/pricing/stream?%s",
							 type, accountInfo.accountID(), query);
	}
		
	private static 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 (MalformedURLException e) {
			e.printStackTrace();
		} catch(SocketTimeoutException e){
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			httpConn.disconnect();
		}
	}

	static ObjectMapper mapper = new ObjectMapper(); // create once, reuse

	private static void processLine(String line, TickProcessor processor) {
		if (line.indexOf ("PRICE") > -1) {
			OANDATick tick;
			try {
				tick = mapper.readValue(line, OANDATick.class);
				processor.process(tick);
			} catch (JsonParseException | JsonMappingException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			}
		} else if (line.indexOf ("HEARTBEAT") > -1) {
			// ignore
		} else {
			System.out.println("Unknown type: " + line);
		}
	}
}