Added sign function for DocumentGateway

src/main/java/com/twikey/DocumentGateway.java

@@ -27,19 +27,19 @@ protected DocumentGateway(TwikeyClient twikeyClient) {
 
     /**
      * <ul>
-     * <li>iban	International Bank Account Number of the debtor	No	string</li>
-     * <li>bic	Bank Identifier Code of the IBAN	No	string</li>
-     * <li>mandateNumber	Mandate Identification number (if not generated)	No	string</li>
-     * <li>contractNumber	The contract number which can override the one defined in the template.	No	string</li>
-     * <li>campaign	Campaign to include this url in	No	string</li>
-     * <li>prefix	Optional prefix to use in the url (default companyname)	No	string</li>
-     * <li>check	If a mandate already exists, don't prepare a new one (based on email, customerNumber or mandatenumber and + template type(=ct))	No	boolean</li>
-     * <li>reminderDays	Send a reminder if contract was not signed after number of days	No	number</li>
-     * <li>sendInvite	Send out invite email directly	No	boolean</li>
-     * <li>document	Add a contract in base64 format	No	string</li>
-     * <li>amount	In euro for a transaction via a first payment or post signature via an SDD transaction	No	string</li>
-     * <li>token	(optional) token to be returned in the exit-url (lenght &lt; 100)	No	string</li>
-     * <li>requireValidation	Always start with the registration page, even with all known mandate details	No	boolean</li>
+     * <li>iban	International Bank Account Number of the debtor</li>
+     * <li>bic	Bank Identifier Code of the IBAN</li>
+     * <li>mandateNumber	Mandate Identification number (if not generated)</li>
+     * <li>contractNumber	The contract number which can override the one defined in the template.</li>
+     * <li>campaign	Campaign to include this url in</li>
+     * <li>prefix	Optional prefix to use in the url (default companyname)</li>
+     * <li>check	If a mandate already exists, don't prepare a new one (based on email, customerNumber or mandatenumber and + template type(=ct))</li>
+     * <li>reminderDays	Send a reminder if contract was not signed after number of days</li>
+     * <li>sendInvite	Send out invite email directly</li>
+     * <li>document	Add a contract in base64 format</li>
+     * <li>amount	In euro for a transaction via a first payment or post signature via an SDD transaction</li>
+     * <li>token	(optional) token to be returned in the exit-url (lenght &lt; 100)</li>
+     * <li>requireValidation	Always start with the registration page, even with all known mandate details</li>
      * </ul>
      *
      * @param ct             Template to use can be found @ <a href="https://www.twikey.com/r/admin#/c/template">https://www.twikey.com/r/admin#/c/template</a>
@@ -48,6 +48,8 @@ protected DocumentGateway(TwikeyClient twikeyClient) {
      * @throws IOException   When no connection could be made
      * @throws com.twikey.TwikeyClient.UserException When Twikey returns a user error (400)
      * @return Url to redirect the customer to or to send in an email
+     * @throws IOException A network error occurred
+     * @throws TwikeyClient.UserException A Twikey generated user error occurred
      */
     public JSONObject create(long ct, Customer customer, Map<String, String> mandateDetails) throws IOException, TwikeyClient.UserException {
         Map<String, String> params = new HashMap<>(mandateDetails);
@@ -86,6 +88,60 @@ public JSONObject create(long ct, Customer customer, Map<String, String> mandate
         }
     }
 
+    /**
+     * Same parameters as invite, but some extra might be required depending on the method
+     * <ul>
+     * <li><b>method (required)</b>:	Method to sign (sms/digisign/import/itsme/emachtiging/paper,...)</li>
+     * <li>digsig:	Wet signature (PDF encoded as base64) required if method is digisign</li>
+     * <li>key:	shortcode from the invite url. Use this parameter instead of 'mandateNumber' to directly sign a prepared mandate.</li>
+     * <li>bic:	Required for methods emachtiging, iDeal and iDIn</li>
+     * <li>signDate:	Date of signature (xsd:dateTime), optional for sms as it uses date of reply</li>
+     * <li>place:	Place of signature</li>
+     * </ul>
+     *
+     * @param ct             Template to use can be found @ <a href="https://www.twikey.com/r/admin#/c/template">https://www.twikey.com/r/admin#/c/template</a>
+     * @param customer       Customer details
+     * @param mandateDetails Map containing any of the parameters in the above table
+     * @return Url to redirect the customer to or to send in an email
+     * @throws IOException A network error occurred
+     * @throws TwikeyClient.UserException A Twikey generated user error occurred
+     */
+    public JSONObject sign(long ct, Customer customer, Map<String, String> mandateDetails) throws IOException, TwikeyClient.UserException {
+        Map<String, String> params = new HashMap<>(mandateDetails);
+        params.put("ct", String.valueOf(ct));
+        if (customer != null) {
+            params.putAll(customer.asFormParameters());
+        }
+
+        URL myurl = twikeyClient.getUrl("/sign");
+        HttpURLConnection con = (HttpURLConnection)myurl.openConnection();
+        con.setRequestMethod("POST");
+        con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
+        con.setRequestProperty("User-Agent", twikeyClient.getUserAgent());
+        con.setRequestProperty("Authorization", twikeyClient.getSessionToken());
+        con.setDoOutput(true);
+        con.setDoInput(true);
+
+        try (DataOutputStream output = new DataOutputStream(con.getOutputStream())) {
+            output.writeBytes(getPostDataString(params));
+            output.flush();
+        }
+
+        int responseCode = con.getResponseCode();
+        if (responseCode == 200) {
+            try (BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream()))) {
+                /* {
+                  "mndtId": "COREREC01",
+                  "url": "http://twikey.to/myComp/ToYG",
+                  "key": "ToYG"
+                } */
+                return new JSONObject(new JSONTokener(br));
+            }
+        } else {
+            String apiError = con.getHeaderField("ApiError");
+            throw new TwikeyClient.UserException(apiError);
+        }
+    }
     /**
      * Get updates about all mandates (new/updated/cancelled)
      *