added leaveTeam and added some comments

src/main/java/hhn/labsw/bugageocaching/controller/Controller.java

@@ -429,12 +429,14 @@ public class Controller {
   @ResponseBody
   public ResponseEntity createTeam(@RequestParam String token,
                                    @RequestParam String name) {
+    // verify user
     ResponseEntity verifyToken = VerificationUtil.verifyToken(token);
 
     if (verifyToken.getStatusCodeValue() != 200) {
       return verifyToken;
     }
 
+    // get user
     Claims claims = (Claims) verifyToken.getBody();
 
     ResponseEntity getUser = FinderUtil.findUserFromClaim(claims);
@@ -458,6 +460,7 @@ public class Controller {
       return ResponseEntity.status(400).body("You already have a team");
     }
 
+    // checkt, ob der name bereits vorhanden ist
     for (Team team : teamRepository.findAll()) {
       if (team.getName().equals(name)) {
         return ResponseEntity.status(400).body("The teamname is already taken");
@@ -479,12 +482,14 @@ public class Controller {
   @ResponseBody
   public ResponseEntity joinTeam(@RequestParam String token,
                                  @RequestParam String teamID) {
+    // verify user
     ResponseEntity verifyToken = VerificationUtil.verifyToken(token);
 
     if (verifyToken.getStatusCodeValue() != 200) {
       return verifyToken;
     }
 
+    // get user
     Claims claims = (Claims) verifyToken.getBody();
 
     ResponseEntity getUser = FinderUtil.findUserFromClaim(claims);
@@ -519,16 +524,19 @@ public class Controller {
 
     int i = 0;
 
+    // zählt teammitglieder
     for (User_Info userInfo1 : user_infoRepository.findAll()) {
       if (userInfo1.getTeam().equals(team)) {
         i++;
       }
     }
 
+    // wenn maximalanzahl der teammitglieder erreicht...
     if (i >= 10) {
       return ResponseEntity.status(400).body("The team already has 10 members");
     }
 
+    // tritt dem team bei
     user_info.setTeam(team);
 
     user_infoRepository.save(user_info);
@@ -536,6 +544,72 @@ public class Controller {
     return ResponseEntity.status(200).body(team);
   }
 
+  @CrossOrigin(origins = "http://localhost:8081") // only for dev purpose
+  @RequestMapping("/api/leaveTeam")
+  @ResponseBody
+  public ResponseEntity leaveTeam(@RequestParam String token) {
+
+    // verify user
+    ResponseEntity verifyToken = VerificationUtil.verifyToken(token);
+
+    if (verifyToken.getStatusCodeValue() != 200) {
+      return verifyToken;
+    }
+
+    //get User
+    Claims claims = (Claims) verifyToken.getBody();
+
+    ResponseEntity getUser = FinderUtil.findUserFromClaim(claims);
+
+    if (getUser.getStatusCodeValue() != 200) {
+      return getUser;
+    }
+
+    User user = (User) getUser.getBody();
+
+    //Get User_Info
+    ResponseEntity getUser_Info = FinderUtil.findUser_InfoByID(String.valueOf(user.getId()));
+
+    if (getUser_Info.getStatusCodeValue() != 200) {
+      return getUser_Info;
+    }
+
+    User_Info user_info = (User_Info) getUser_Info.getBody();
+    //----------------------
+    if (user_info.getTeam() == null) {
+      return ResponseEntity.status(400).body("You aren´t in any team");
+    }
+
+    //Get team
+    ResponseEntity getTeam = FinderUtil.findTeamById(String.valueOf(user_info.getTeam().getId()));
+
+    if (getTeam.getStatusCodeValue() != 200) {
+      return getTeam;
+    }
+
+    Team team = (Team) getTeam.getBody();
+
+    // verlässt team
+    user_info.setTeam(null);
+
+    int i = 0;
+    // zählt teammitglieder
+    for (User_Info userInfo1 : user_infoRepository.findAll()) {
+      if (userInfo1.getTeam().equals(team)) {
+        i++;
+      }
+    }
+
+    // löscht team, wenn keine teammitglieder mehr vorhanden
+    if (i == 0) {
+      teamRepository.delete(team);
+    }
+
+    user_infoRepository.save(user_info);
+
+    return ResponseEntity.status(200).body("Ok");
+  }
+
   @RequestMapping("/api/hello")
   public ResponseEntity hello(@RequestParam String name) {
     return ResponseEntity.status(200).body(userRepository.getRankingPlaceFromUser(name));