From 8c8acd50782b5d64b2a5a57fe8f9a4c2385203fd Mon Sep 17 00:00:00 2001
From: =?utf8?q?David=20=E2=80=98Bombe=E2=80=99=20Roden?=
 <bombe@pterodactylus.net>
Date: Thu, 21 Oct 2010 23:11:38 +0200
Subject: [PATCH] Add request change filter.

---
 .../sone/template/RequestChangeFilter.java         | 93 ++++++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 src/main/java/net/pterodactylus/sone/template/RequestChangeFilter.java

diff --git a/src/main/java/net/pterodactylus/sone/template/RequestChangeFilter.java b/src/main/java/net/pterodactylus/sone/template/RequestChangeFilter.java
new file mode 100644
index 0000000..d9c453e
--- /dev/null
+++ b/src/main/java/net/pterodactylus/sone/template/RequestChangeFilter.java
@@ -0,0 +1,93 @@
+/*
+ * Sone - RequestChangeFilter.java - Copyright © 2010 David Roden
+ *
+ * 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 net.pterodactylus.sone.template;
+
+import java.io.UnsupportedEncodingException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URLEncoder;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import net.pterodactylus.sone.web.page.Page.Request;
+import net.pterodactylus.util.template.DataProvider;
+import net.pterodactylus.util.template.Filter;
+
+/**
+ * This filter expects a {@link Request} as input and outputs a {@link URI} that
+ * is modified by the parameters. The name of the parameter is handed in as
+ * “name”, the value may either be stored in “value”, or in a template variable
+ * whose key is stored in “key”.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class RequestChangeFilter implements Filter {
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public Object format(DataProvider dataProvider, Object data, Map<String, String> parameters) {
+		Request request = (Request) data;
+		String name = parameters.get("name");
+		String key = parameters.get("key");
+		String value = null;
+		if (key != null) {
+			value = String.valueOf(dataProvider.getData(key));
+		}
+		if (value == null) {
+			value = parameters.get("value");
+		}
+		if (value == null) {
+			return request.getUri();
+		}
+
+		Map<String, String> values = new HashMap<String, String>();
+		Collection<String> parameterNames = request.getHttpRequest().getParameterNames();
+		for (String parameterName : parameterNames) {
+			values.put(parameterName, request.getHttpRequest().getParam(parameterName));
+		}
+		values.put(name, value);
+
+		StringBuilder query = new StringBuilder();
+		try {
+			for (Entry<String, String> parameterEntry : values.entrySet()) {
+				query.append((query.length() == 0) ? '?' : '&');
+				query.append(URLEncoder.encode(parameterEntry.getKey(), "UTF-8"));
+				query.append('=');
+				query.append(URLEncoder.encode(parameterEntry.getValue(), "UTF-8"));
+			}
+			String oldUri = request.getUri().toString();
+			int questionMark = oldUri.indexOf('?');
+			if (questionMark == -1) {
+				questionMark = oldUri.length();
+			}
+			URI u = new URI(oldUri.substring(0, questionMark) + query.toString());
+			System.out.println("u: " + u);
+			return u;
+		} catch (UnsupportedEncodingException uee1) {
+			/* UTF-8 not supported? I don’t think so. */
+		} catch (URISyntaxException use1) {
+			use1.printStackTrace();
+		}
+		return null;
+	}
+
+}
-- 
2.7.4