hashengineering.digitalcoin.wallet.ExchangeRatesProvider.java Source code

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Here is the source code for hashengineering.digitalcoin.wallet.ExchangeRatesProvider.java

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/*
 * Copyright 2011-2013 the original author or authors.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package hashengineering.digitalcoin.wallet;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.math.BigInteger;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.*;

import javax.annotation.CheckForNull;
import javax.annotation.Nonnull;

import com.google.digitalcoin.core.CoinDefinition;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.provider.BaseColumns;
import android.text.format.DateUtils;

import com.google.digitalcoin.core.Utils;

import hashengineering.digitalcoin.wallet.util.GenericUtils;
import hashengineering.digitalcoin.wallet.util.Io;

/**
 * @author Andreas Schildbach
 */
public class ExchangeRatesProvider extends ContentProvider {
    public static class ExchangeRate {
        public ExchangeRate(@Nonnull final String currencyCode, @Nonnull final BigInteger rate,
                @Nonnull final String source) {
            this.currencyCode = currencyCode;
            this.rate = rate;
            this.source = source;
        }

        public final String currencyCode;
        public final BigInteger rate;
        public final String source;

        @Override
        public String toString() {
            return getClass().getSimpleName() + '[' + currencyCode + ':'
                    + GenericUtils.formatValue(rate, Constants.BTC_MAX_PRECISION) + ']';
        }
    }

    public static final String KEY_CURRENCY_CODE = "currency_code";
    private static final String KEY_RATE = "rate";
    private static final String KEY_SOURCE = "source";

    @CheckForNull
    private Map<String, ExchangeRate> exchangeRates = null;
    private long lastUpdated = 0;

    private static final long UPDATE_FREQ_MS = 10 * DateUtils.MINUTE_IN_MILLIS;

    private static final Logger log = LoggerFactory.getLogger(ExchangeRatesProvider.class);

    @Override
    public boolean onCreate() {
        return true;
    }

    public static Uri contentUri(@Nonnull final String packageName) {
        return Uri.parse("content://" + packageName + '.' + "exchange_rates");
    }

    @Override
    public Cursor query(final Uri uri, final String[] projection, final String selection,
            final String[] selectionArgs, final String sortOrder) {
        final long now = System.currentTimeMillis();

        if (exchangeRates == null || now - lastUpdated > UPDATE_FREQ_MS) {
            Map<String, ExchangeRate> newExchangeRates = getBitcoinCharts();
            if (exchangeRates == null && newExchangeRates == null)
                newExchangeRates = getBlockchainInfo();

            if (newExchangeRates != null) {
                exchangeRates = newExchangeRates;
                lastUpdated = now;
            }
        }

        if (exchangeRates == null)
            return null;

        final MatrixCursor cursor = new MatrixCursor(
                new String[] { BaseColumns._ID, KEY_CURRENCY_CODE, KEY_RATE, KEY_SOURCE });

        if (selection == null) {
            for (final Map.Entry<String, ExchangeRate> entry : exchangeRates.entrySet()) {
                final ExchangeRate rate = entry.getValue();
                cursor.newRow().add(rate.currencyCode.hashCode()).add(rate.currencyCode).add(rate.rate.longValue())
                        .add(rate.source);
            }
        } else if (selection.equals(KEY_CURRENCY_CODE)) {
            final String selectedCode = selectionArgs[0];
            ExchangeRate rate = selectedCode != null ? exchangeRates.get(selectedCode) : null;

            if (rate == null) {
                final String defaultCode = defaultCurrencyCode();
                rate = defaultCode != null ? exchangeRates.get(defaultCode) : null;

                if (rate == null) {
                    rate = exchangeRates.get(Constants.DEFAULT_EXCHANGE_CURRENCY);

                    if (rate == null)
                        return null;
                }
            }

            cursor.newRow().add(rate.currencyCode.hashCode()).add(rate.currencyCode).add(rate.rate.longValue())
                    .add(rate.source);
        }

        return cursor;
    }

    private String defaultCurrencyCode() {
        try {
            return Currency.getInstance(Locale.getDefault()).getCurrencyCode();
        } catch (final IllegalArgumentException x) {
            return null;
        }
    }

    public static ExchangeRate getExchangeRate(@Nonnull final Cursor cursor) {
        final String currencyCode = cursor
                .getString(cursor.getColumnIndexOrThrow(ExchangeRatesProvider.KEY_CURRENCY_CODE));
        final BigInteger rate = BigInteger
                .valueOf(cursor.getLong(cursor.getColumnIndexOrThrow(ExchangeRatesProvider.KEY_RATE)));
        final String source = cursor.getString(cursor.getColumnIndexOrThrow(ExchangeRatesProvider.KEY_SOURCE));

        return new ExchangeRate(currencyCode, rate, source);
    }

    @Override
    public Uri insert(final Uri uri, final ContentValues values) {
        throw new UnsupportedOperationException();
    }

    @Override
    public int update(final Uri uri, final ContentValues values, final String selection,
            final String[] selectionArgs) {
        throw new UnsupportedOperationException();
    }

    @Override
    public int delete(final Uri uri, final String selection, final String[] selectionArgs) {
        throw new UnsupportedOperationException();
    }

    @Override
    public String getType(final Uri uri) {
        throw new UnsupportedOperationException();
    }

    private static Object getCoinValueBTC() {
        Date date = new Date();
        long now = date.getTime();

        //final Map<String, ExchangeRate> rates = new TreeMap<String, ExchangeRate>();
        // Keep the LTC rate around for a bit
        Double btcRate = 0.0;
        String currencyCryptsy = CoinDefinition.cryptsyMarketCurrency;
        String urlCryptsy = "http://pubapi.cryptsy.com/api.php?method=singlemarketdata&marketid="
                + CoinDefinition.cryptsyMarketId;

        try {
            // final String currencyCode = currencies[i];
            final URL URLCryptsy = new URL(urlCryptsy);
            final URLConnection connectionCryptsy = URLCryptsy.openConnection();
            connectionCryptsy.setConnectTimeout(Constants.HTTP_TIMEOUT_MS * 2);
            connectionCryptsy.setReadTimeout(Constants.HTTP_TIMEOUT_MS * 2);
            connectionCryptsy.connect();

            final StringBuilder contentCryptsy = new StringBuilder();

            Reader reader = null;
            try {
                reader = new InputStreamReader(new BufferedInputStream(connectionCryptsy.getInputStream(), 1024));
                Io.copy(reader, contentCryptsy);
                final JSONObject head = new JSONObject(contentCryptsy.toString());
                JSONObject returnObject = head.getJSONObject("return");
                JSONObject markets = returnObject.getJSONObject("markets");
                JSONObject coinInfo = markets.getJSONObject(CoinDefinition.coinTicker);

                JSONArray recenttrades = coinInfo.getJSONArray("recenttrades");

                double btcTraded = 0.0;
                double coinTraded = 0.0;

                for (int i = 0; i < recenttrades.length(); ++i) {
                    JSONObject trade = (JSONObject) recenttrades.get(i);

                    btcTraded += trade.getDouble("total");
                    coinTraded += trade.getDouble("quantity");

                }

                Double averageTrade = btcTraded / coinTraded;

                //Double lastTrade = GLD.getDouble("lasttradeprice");

                //String euros = String.format("%.7f", averageTrade);
                // Fix things like 3,1250
                //euros = euros.replace(",", ".");
                //rates.put(currencyCryptsy, new ExchangeRate(currencyCryptsy, Utils.toNanoCoins(euros), URLCryptsy.getHost()));
                if (currencyCryptsy.equalsIgnoreCase("BTC"))
                    btcRate = averageTrade;

            } finally {
                if (reader != null)
                    reader.close();
            }
            return btcRate;
        } catch (final IOException x) {
            x.printStackTrace();
        } catch (final JSONException x) {
            x.printStackTrace();
        }

        return null;
    }

    private static Map<String, ExchangeRate> getBitcoinCharts() {
        try {
            Double btcRate = 0.0;

            Object result = getCoinValueBTC();

            if (result == null)
                return null;

            else
                btcRate = (Double) result;

            final URL URL = new URL("http://api.bitcoincharts.com/v1/weighted_prices.json");
            final HttpURLConnection connection = (HttpURLConnection) URL.openConnection();
            connection.setConnectTimeout(Constants.HTTP_TIMEOUT_MS);
            connection.setReadTimeout(Constants.HTTP_TIMEOUT_MS);
            connection.connect();

            if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
                return null;

            Reader reader = null;
            try {
                reader = new InputStreamReader(new BufferedInputStream(connection.getInputStream(), 1024),
                        Constants.UTF_8);
                final StringBuilder content = new StringBuilder();
                Io.copy(reader, content);

                final Map<String, ExchangeRate> rates = new TreeMap<String, ExchangeRate>();

                //Add Bitcoin information
                rates.put(CoinDefinition.cryptsyMarketCurrency,
                        new ExchangeRate(CoinDefinition.cryptsyMarketCurrency,
                                Utils.toNanoCoins(String.format("%.8f", btcRate).replace(",", ".")),
                                "pubapi.cryptsy.com"));

                final JSONObject head = new JSONObject(content.toString());
                for (final Iterator<String> i = head.keys(); i.hasNext();) {
                    final String currencyCode = i.next();
                    if (!"timestamp".equals(currencyCode)) {
                        final JSONObject o = head.getJSONObject(currencyCode);
                        String rate = o.optString("24h", null);
                        if (rate == null)
                            rate = o.optString("7d", null);
                        if (rate == null)
                            rate = o.optString("30d", null);

                        double rateForBTC = Double.parseDouble(rate);

                        rate = String.format("%.8f", rateForBTC * btcRate);

                        if (rate != null) {
                            try {
                                rates.put(currencyCode, new ExchangeRate(currencyCode,
                                        Utils.toNanoCoins(rate.replace(",", ".")), URL.getHost()));
                            } catch (final ArithmeticException x) {
                                log.debug("problem reading exchange rate: " + currencyCode, x);
                            }
                        }
                    }
                }

                return rates;
            } finally {
                if (reader != null)
                    reader.close();
            }
        } catch (final Exception x) {
            log.debug("problem reading exchange rates", x);
        }

        return null;
    }

    private static Map<String, ExchangeRate> getBlockchainInfo() {
        try {
            Double btcRate = 0.0;

            Object result = getCoinValueBTC();

            if (result == null)
                return null;

            else
                btcRate = (Double) result;

            final URL URL = new URL("https://blockchain.info/ticker");
            final HttpURLConnection connection = (HttpURLConnection) URL.openConnection();
            connection.setConnectTimeout(Constants.HTTP_TIMEOUT_MS);
            connection.setReadTimeout(Constants.HTTP_TIMEOUT_MS);
            connection.connect();

            if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
                return null;

            Reader reader = null;
            try {
                reader = new InputStreamReader(new BufferedInputStream(connection.getInputStream(), 1024),
                        Constants.UTF_8);
                final StringBuilder content = new StringBuilder();
                Io.copy(reader, content);

                final Map<String, ExchangeRate> rates = new TreeMap<String, ExchangeRate>();

                //Add Bitcoin information
                rates.put(CoinDefinition.cryptsyMarketCurrency,
                        new ExchangeRate(CoinDefinition.cryptsyMarketCurrency,
                                Utils.toNanoCoins(String.format("%.8f", btcRate).replace(",", ".")),
                                "pubapi.cryptsy.com"));

                final JSONObject head = new JSONObject(content.toString());
                for (final Iterator<String> i = head.keys(); i.hasNext();) {
                    final String currencyCode = i.next();
                    final JSONObject o = head.getJSONObject(currencyCode);
                    //final String rate = o.optString("15m", null);

                    double rateForBTC = o.getDouble("15m") * btcRate;

                    final String rate = String.format("%.8f", rateForBTC); //o.optString("15m", null);

                    if (rate != null) {
                        try {
                            rates.put(currencyCode, new ExchangeRate(currencyCode,
                                    Utils.toNanoCoins(rate.replace(",", ".")), URL.getHost()));
                        } catch (final ArithmeticException x) {
                            log.debug("problem reading exchange rate: " + currencyCode, x);
                        }
                    }
                }

                return rates;
            } finally {
                if (reader != null)
                    reader.close();
            }
        } catch (final Exception x) {
            log.debug("problem reading exchange rates", x);
        }

        return null;
    }

    // https://bitmarket.eu/api/ticker
}