Add Service for Group Registration (#1636)

modules/fbs-core/api/src/main/scala/de/thm/ii/fbs/services/persistence/GroupRegistrationService.scala

@@ -0,0 +1,112 @@
+package de.thm.ii.fbs.services.persistence
+
+import de.thm.ii.fbs.model._
+import de.thm.ii.fbs.util.DB
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.jdbc.core.JdbcTemplate
+import org.springframework.stereotype.Component
+
+import java.sql.ResultSet
+import org.springframework.jdbc.core.RowMapper
+
+/**
+  * Handles group registration and participants.
+  */
+@Component
+class GroupRegistrationService {
+  @Autowired
+  private implicit val jdbc: JdbcTemplate = null
+
+  /**
+    * Add a user to a group
+    * 
+    * @param uid User id
+    * @param cid Course id
+    * @param gid Group id
+    * @return True if successful
+    */
+  def addUserToGroup(uid:Int, cid: Int, gid: Int): Boolean =
+    1 == DB.update("INSERT INTO user_group (user_id, course_id, group_id) VALUES (?,?,?);",uid, cid, gid)
+
+  /**
+    * Remove a user from a group
+    *
+    * @param uid User id
+    * @param cid Course id
+    * @param gid Group id 
+    * @return True if sucessfully deregistered
+    */
+  def removeUserFromGroup(uid: Int, cid: Int, gid: Int): Boolean =
+    1 == DB.update("DELETE FROM user_group WHERE user_id = ? AND course_id = ? AND group_id = ?",uid, cid, gid)
+
+  /**
+    * Remove all users from a group
+    *
+    * @param cid Course id
+    * @param gid Group id 
+    * @return True if sucessfully deregistered
+    */
+  def removeAllUsersFromGroup(cid: Int, gid: Int): Boolean = 
+    1 == DB.update("DELETE FROM user_group WHERE course_id = ? AND group_id = ?", cid, gid)
+
+  /**
+    * Retrieve all groups of a specific user
+    *
+    * @param uid User id
+    * @param ignoreHidden True if hidden groups should be ignored
+    * @return List of groups
+    */
+  def getUserGroups(uid: Int, ignoreHidden: Boolean = true): List[Group] = DB.query(
+    "SELECT g.group_id, g.course_id, g.name, g.membership, g.visible FROM `group` g JOIN user_group ug ON g.group_id = ug.group_id WHERE ug.user_id = ? ORDER BY g.course_id ASC"
+      + (if (ignoreHidden) " AND g.visible = 1" else ""),
+    (res, _) => parseResult(res), uid)
+
+  /**
+    * Get all members of a group
+    *
+    * @param cid Course id
+    * @param gid Group id
+    * @return List of members 
+    */
+  def getMembers(cid: Int, gid: Int): List[Participant] = DB.query(
+    "SELECT u.user_id, u.prename, u.surname, u.email, u.username, u.alias, u.global_role, uc.course_role " +
+      "FROM user u " +
+      "JOIN user_course uc ON u.user_id = uc.user_id " +
+      "JOIN user_group ug ON uc.course_id = ug.course_id AND uc.user_id = ug.user_id " +
+      "WHERE u.deleted = 0 AND ug.course_id = ? AND ug.group_id = ?",
+    (res, _) => Participant(parseUserResult(res), CourseRole.parse(res.getInt("course_role"))), cid, gid)
+
+  /**
+    * Gets current number of members of a group
+    * 
+    * @param cid Course id
+    * @param gid Group id
+    * @return Number of members 
+    */
+  def getGroupMembership(cid: Int, gid: Int) : Int = {
+    val groupMembershipRowMapper: RowMapper[Int] = (rs: ResultSet, rowNum: Int) => rs.getInt(1)
+    val sql = "SELECT COUNT(*) FROM user_group  WHERE course_id = ? AND group_id = ?"
+    return jdbc.queryForObject(sql, groupMembershipRowMapper, cid, gid);
+  } 
+
+  private def parseResult(res: ResultSet): Group = Group(
+    id = res.getInt("group_id"),
+    courseId = res.getInt("course_id"),
+    name = res.getString("name"),
+    membership = res.getInt("membership"),
+    visible = res.getBoolean("visible"),
+  )
+
+  private def parseUserResult(res: ResultSet): User = new User(
+    prename = res.getString("prename"),
+    surname = res.getString("surname"),
+    email = res.getString("email"),
+    username = res.getString("username"),
+    globalRole = GlobalRole.parse(res.getInt("global_role")),
+    alias = Option(res.getString("alias")),
+    id = res.getInt("user_id")
+  )
+}
+
+
+