started working on templates and api

src/main/java/de/srsoftware/widerhall/web/Rest.java

@@ -1,5 +1,7 @@
 package de.srsoftware.widerhall.web;
 
+import de.srsoftware.widerhall.data.User;
+import org.json.simple.JSONObject;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -8,14 +10,47 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+import static de.srsoftware.widerhall.Constants.*;
+import static de.srsoftware.widerhall.Util.t;
 
 public class Rest extends HttpServlet {
-
     private static final Logger LOG = LoggerFactory.getLogger(Rest.class);
+    private static final String USER_LIST = "user/list";
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
-        String method = req.getMethod();
-        LOG.debug("GET {}"+method);
+        String error = handleGet(req, resp);
+        if (error != null) resp.sendError(400,error);
+    }
 
+    public String handleGet(HttpServletRequest req, HttpServletResponse resp){
+        Object o = req.getSession().getAttribute(USER);
+        JSONObject json = new JSONObject();
+        if (o instanceof User user){
+            var path = req.getPathInfo();
+            json.put(USER,safeMapUser(user));
+            path = path == null ? INDEX : path.substring(1);
+            switch (path) {
+                case USER_LIST:
+                    json.put("users", (user.is(ADMIN) ? User.list() : List.of(user)).stream().map(Rest::safeMapUser).toList());
+                    break;
+
+            }
+        } else {
+            json.put(ERROR,"Not logged in!");
+        }
+        try {
+            resp.getWriter().println(json.toJSONString());
+            return null;
+        } catch (IOException e) {
+            return t("Failed to handle request: {}",e.getMessage());
+        }
+    }
+
+    private static Map<String,String> safeMapUser(User user){
+        return Map.of(NAME,user.name(),EMAIL,user.email(),PASSWORD,user.hashedPassword() == null ? "no" : "yes");
     }
 }