/*
* Copyright 2012 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 com.google.bitcoin.uri;
import com.google.bitcoin.core.Address;
import com.google.bitcoin.core.AddressFormatException;
import com.google.bitcoin.core.NetworkParameters;
import com.google.bitcoin.core.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nullable;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URLDecoder;
import java.util.LinkedHashMap;
import java.util.Map;
import static com.google.common.base.Preconditions.checkNotNull;
/**
* <p>Provides a standard implementation of a Bitcoin URI with support for the following:</p>
*
* <ul>
* <li>URLEncoded URIs (as passed in by IE on the command line)</li>
* <li>BIP21 names (including the "req-" prefix handling requirements)</li>
* </ul>
*
* <h2>Accepted formats</h2>
*
* <p>The following input forms are accepted:</p>
*
* <ul>
* <li>{@code bitcoin:<address>}</li>
* <li>{@code bitcoin:<address>?<name1>=<value1>&<name2>=<value2>} with multiple
* additional name/value pairs</li>
* </ul>
*
* <p>The name/value pairs are processed as follows.</p>
* <ol>
* <li>URL encoding is stripped and treated as UTF-8</li>
* <li>names prefixed with {@code req-} are treated as required and if unknown or conflicting cause a parse exception</li>
* <li>Unknown names not prefixed with {@code req-} are added to a Map, accessible by parameter name</li>
* <li>Known names not prefixed with {@code req-} are processed unless they are malformed</li>
* </ol>
*
* <p>The following names are known and have the following formats:</p>
* <ul>
* <li>{@code amount} decimal value to 8 dp (e.g. 0.12345678) <b>Note that the
* exponent notation is not supported any more</b></li>
* <li>{@code label} any URL encoded alphanumeric</li>
* <li>{@code message} any URL encoded alphanumeric</li>
* </ul>
*
* @author Andreas Schildbach (initial code)
* @author Jim Burton (enhancements for MultiBit)
* @author Gary Rowe (BIP21 support)
* @see <a href="https://en.bitcoin.it/wiki/BIP_0021">BIP 0021</a>
*/
public class BitcoinURI {
/**
* Provides logging for this class
*/
private static final Logger log = LoggerFactory.getLogger(BitcoinURI.class);
// Not worth turning into an enum
public static final String FIELD_MESSAGE = "message";
public static final String FIELD_LABEL = "label";
public static final String FIELD_AMOUNT = "amount";
public static final String FIELD_ADDRESS = "address";
public static final String FIELD_PAYMENT_REQUEST_URL = "r";
public static final String BITCOIN_SCHEME = "bitcoin";
private static final String ENCODED_SPACE_CHARACTER = "%20";
private static final String AMPERSAND_SEPARATOR = "&";
private static final String QUESTION_MARK_SEPARATOR = "?";
/**
* Contains all the parameters in the order in which they were processed
*/
private final Map<String, Object> parameterMap = new LinkedHashMap<String, Object>();
/**
* Constructs a new BitcoinURI from the given string. Can be for any network.
*
* @param uri The raw URI data to be parsed (see class comments for accepted formats)
* @throws BitcoinURIParseException if the URI is not syntactically or semantically valid.
*/
public BitcoinURI(String uri) throws BitcoinURIParseException {
this(null, uri);
}
/**
* Constructs a new object by trying to parse the input as a valid Bitcoin URI.
*
* @param params The network parameters that determine which network the URI is from, or null if you don't have
* any expectation about what network the URI is for and wish to check yourself.
* @param input The raw URI data to be parsed (see class comments for accepted formats)
*
* @throws BitcoinURIParseException If the input fails Bitcoin URI syntax and semantic checks.
*/
public BitcoinURI(@Nullable NetworkParameters params, String input) throws BitcoinURIParseException {
checkNotNull(input);
log.debug("Attempting to parse '{}' for {}", input, params == null ? "any" : params.getId());
// Attempt to form the URI (fail fast syntax checking to official standards).
URI uri;
try {
uri = new URI(input);
} catch (URISyntaxException e) {
throw new BitcoinURIParseException("Bad URI syntax", e);
}
// URI is formed as bitcoin:<address>?<query parameters>
// blockchain.info generates URIs of non-BIP compliant form bitcoin://address?....
// We support both until Ben fixes his code.
// Remove the bitcoin scheme.
// (Note: getSchemeSpecificPart() is not used as it unescapes the label and parse then fails.
// For instance with : bitcoin:129mVqKUmJ9uwPxKJBnNdABbuaaNfho4Ha?amount=0.06&label=Tom%20%26%20Jerry
// the & (%26) in Tom and Jerry gets interpreted as a separator and the label then gets parsed
// as 'Tom ' instead of 'Tom & Jerry')
String schemeSpecificPart;
if (input.startsWith("bitcoin://")) {
schemeSpecificPart = input.substring("bitcoin://".length());
} else if (input.startsWith("bitcoin:")) {
schemeSpecificPart = input.substring("bitcoin:".length());
} else {
throw new BitcoinURIParseException("Unsupported URI scheme: " + uri.getScheme());
}
// Split off the address from the rest of the query parameters.
String[] addressSplitTokens = schemeSpecificPart.split("\\?");
if (addressSplitTokens.length == 0)
throw new BitcoinURIParseException("No data found after the bitcoin: prefix");
String addressToken = addressSplitTokens[0]; // may be empty!
String[] nameValuePairTokens;
if (addressSplitTokens.length == 1) {
// Only an address is specified - use an empty '<name>=<value>' token array.
nameValuePairTokens = new String[] {};
} else {
if (addressSplitTokens.length == 2) {
// Split into '<name>=<value>' tokens.
nameValuePairTokens = addressSplitTokens[1].split("&");
} else {
throw new BitcoinURIParseException("Too many question marks in URI '" + uri + "'");
}
}
// Attempt to parse the rest of the URI parameters.
parseParameters(params, addressToken, nameValuePairTokens);
if (!addressToken.isEmpty()) {
// Attempt to parse the addressToken as a Bitcoin address for this network
try {
Address address = new Address(params, addressToken);
putWithValidation(FIELD_ADDRESS, address);
} catch (final AddressFormatException e) {
throw new BitcoinURIParseException("Bad address", e);
}
}
if (addressToken.isEmpty() && getPaymentRequestUrl() == null) {
throw new BitcoinURIParseException("No address and no r= parameter found");
}
}
/**
* @param params The network parameters or null
* @param nameValuePairTokens The tokens representing the name value pairs (assumed to be
* separated by '=' e.g. 'amount=0.2')
*/
private void parseParameters(@Nullable NetworkParameters params, String addressToken, String[] nameValuePairTokens) throws BitcoinURIParseException {
// Attempt to decode the rest of the tokens into a parameter map.
for (String nameValuePairToken : nameValuePairTokens) {
String[] tokens = nameValuePairToken.split("=");
if (tokens.length != 2 || "".equals(tokens[0])) {
throw new BitcoinURIParseException("Malformed Bitcoin URI - cannot parse name value pair '" +
nameValuePairToken + "'");
}
String nameToken = tokens[0].toLowerCase();
String valueToken = tokens[1];
// Parse the amount.
if (FIELD_AMOUNT.equals(nameToken)) {
// Decode the amount (contains an optional decimal component to 8dp).
try {
BigInteger amount = Utils.toNanoCoins(valueToken);
putWithValidation(FIELD_AMOUNT, amount);
} catch (NumberFormatException e) {
throw new OptionalFieldValidationException(String.format("'%s' is not a valid amount", valueToken), e);
} catch (ArithmeticException e) {
throw new OptionalFieldValidationException(String.format("'%s' has too many decimal places", valueToken), e);
}
} else {
if (nameToken.startsWith("req-")) {
// A required parameter that we do not know about.
throw new RequiredFieldValidationException("'" + nameToken + "' is required but not known, this URI is not valid");
} else {
// Known fields and unknown parameters that are optional.
try {
putWithValidation(nameToken, URLDecoder.decode(valueToken, "UTF-8"));
} catch (UnsupportedEncodingException e) {
// Unreachable.
throw new RuntimeException(e);
}
}
}
}
// Note to the future: when you want to implement 'req-expires' have a look at commit 410a53791841
// which had it in.
}
/**
* Put the value against the key in the map checking for duplication. This avoids address field overwrite etc.
*
* @param key The key for the map
* @param value The value to store
*/
private void putWithValidation(String key, Object value) throws BitcoinURIParseException {
if (parameterMap.containsKey(key)) {
throw new BitcoinURIParseException(String.format("'%s' is duplicated, URI is invalid", key));
} else {
parameterMap.put(key, value);
}
}
/**
* The Bitcoin Address from the URI, if one was present. It's possible to have Bitcoin URI's with no address if a
* r= payment protocol parameter is specified, though this form is not recommended as older wallets can't understand
* it.
*/
@Nullable
public Address getAddress() {
return (Address) parameterMap.get(FIELD_ADDRESS);
}
/**
* @return The amount name encoded using a pure integer value based at
* 10,000,000 units is 1 BTC. May be null if no amount is specified
*/
public BigInteger getAmount() {
return (BigInteger) parameterMap.get(FIELD_AMOUNT);
}
/**
* @return The label from the URI.
*/
public String getLabel() {
return (String) parameterMap.get(FIELD_LABEL);
}
/**
* @return The message from the URI.
*/
public String getMessage() {
return (String) parameterMap.get(FIELD_MESSAGE);
}
/**
* @return The URL where a payment request (as specified in BIP 70) may
* be fetched.
*/
public String getPaymentRequestUrl() {
return (String) parameterMap.get(FIELD_PAYMENT_REQUEST_URL);
}
/**
* @param name The name of the parameter
* @return The parameter value, or null if not present
*/
public Object getParameterByName(String name) {
return parameterMap.get(name);
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder("BitcoinURI[");
boolean first = true;
for (Map.Entry<String, Object> entry : parameterMap.entrySet()) {
if (first) {
first = false;
} else {
builder.append(",");
}
builder.append("'").append(entry.getKey()).append("'=").append("'").append(entry.getValue().toString()).append("'");
}
builder.append("]");
return builder.toString();
}
public static String convertToBitcoinURI(Address address, BigInteger amount, String label, String message) {
return convertToBitcoinURI(address.toString(), amount, label, message);
}
/**
* Simple Bitcoin URI builder using known good fields.
*
* @param address The Bitcoin address
* @param amount The amount in nanocoins (decimal)
* @param label A label
* @param message A message
* @return A String containing the Bitcoin URI
*/
public static String convertToBitcoinURI(String address, @Nullable BigInteger amount, @Nullable String label,
@Nullable String message) {
checkNotNull(address);
if (amount != null && amount.compareTo(BigInteger.ZERO) < 0) {
throw new IllegalArgumentException("Amount must be positive");
}
StringBuilder builder = new StringBuilder();
builder.append(BITCOIN_SCHEME).append(":").append(address);
boolean questionMarkHasBeenOutput = false;
if (amount != null) {
builder.append(QUESTION_MARK_SEPARATOR).append(FIELD_AMOUNT).append("=");
builder.append(Utils.bitcoinValueToPlainString(amount));
questionMarkHasBeenOutput = true;
}
if (label != null && !"".equals(label)) {
if (questionMarkHasBeenOutput) {
builder.append(AMPERSAND_SEPARATOR);
} else {
builder.append(QUESTION_MARK_SEPARATOR);
questionMarkHasBeenOutput = true;
}
builder.append(FIELD_LABEL).append("=").append(encodeURLString(label));
}
if (message != null && !"".equals(message)) {
if (questionMarkHasBeenOutput) {
builder.append(AMPERSAND_SEPARATOR);
} else {
builder.append(QUESTION_MARK_SEPARATOR);
}
builder.append(FIELD_MESSAGE).append("=").append(encodeURLString(message));
}
return builder.toString();
}
/**
* Encode a string using URL encoding
*
* @param stringToEncode The string to URL encode
*/
static String encodeURLString(String stringToEncode) {
try {
return java.net.URLEncoder.encode(stringToEncode, "UTF-8").replace("+", ENCODED_SPACE_CHARACTER);
} catch (UnsupportedEncodingException e) {
// should not happen - UTF-8 is a valid encoding
throw new RuntimeException(e);
}
}
}