ADD: added database connection for players data handling and started login funtion with database

2025-05-30 15:02:23 +02:00
parent 4158b87576
commit 1a2eec44a9
19 changed files with 924 additions and 58 deletions
--- a/backend/cmd/server/main.go
+++ b/backend/cmd/server/main.go
@@ -3,6 +3,8 @@ package main
 import (
 	"os"
 	"volleyball/internal/auth"
+	"volleyball/internal/database"
+	"volleyball/internal/player"
 	"volleyball/internal/tournament"

 	"github.com/gin-contrib/cors"
@@ -10,6 +12,19 @@ import (
 )

 func main() {
+
+	var host = "localhost"
+	var DBport = 5432
+	var user = "volleyball"
+
+	db := database.New(host, DBport, user, "volleyball", "volleyball")
+	db.Connect()
+
+	// Setup the database and tables
+	if err := db.SetupTables(); err != nil {
+		os.Exit(1)
+	}
+
 	r := gin.Default()

 	// CORS
@@ -21,7 +36,10 @@ func main() {
 	}))

 	// Public
-	r.POST("/api/login", auth.LoginHandler)
+	r.POST("/api/login", func(c *gin.Context) {
+		auth.LoginHandler(c, db.GetDB())
+	})
+
 	r.GET("/api/tournaments", tournament.ListTournaments)

 	// Protected API
@@ -32,6 +50,19 @@ func main() {
 	api.POST("/tournaments/:id/join", tournament.JoinTournament)
 	api.PUT("/tournaments/:id", tournament.UpdateTournament)

+	api.GET("/players", func(c *gin.Context) {
+		player.GetPlayers(c, db.GetDB())
+	})
+	api.POST("/players", func(c *gin.Context) {
+		player.CreatePlayer(c, db.GetDB())
+	})
+	api.PUT("/players/:id", func(c *gin.Context) {
+		player.UpdatePlayer(c, db.GetDB())
+	})
+	api.DELETE("/players/:id", func(c *gin.Context) {
+		player.DeletePlayer(c, db.GetDB())
+	})
+
 	port := os.Getenv("PORT")
 	if port == "" {
 		port = "8080"
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -23,6 +23,7 @@ require (
 	github.com/go-playground/validator/v10 v10.26.0 // indirect
 	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/golang-jwt/jwt/v4 v4.5.2
+	github.com/google/uuid v1.6.0
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.10 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
--- a/backend/go.sum
+++ b/backend/go.sum
@@ -33,6 +33,8 @@ github.com/golang-jwt/jwt/v4 v4.5.2/go.mod h1:m21LjoU+eqJr34lmDMbreY2eSTRJ1cv77w
 github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=
--- a/backend/internal/auth/handler.go
+++ b/backend/internal/auth/handler.go
@@ -1,8 +1,11 @@
 package auth

 import (
+	"database/sql"
 	"net/http"
 	"time"
+	"volleyball/internal/common"
+	"volleyball/internal/player"

 	"github.com/gin-gonic/gin"
 )
@@ -16,23 +19,53 @@ type LoginResponse struct {
 	Token string `json:"token"`
 }

-func LoginHandler(c *gin.Context) {
+func LoginHandler(c *gin.Context, db *sql.DB) {
 	var req LoginRequest
 	if err := c.ShouldBindJSON(&req); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"error": "Bad request"})
 		return
 	}

-	// Systemnutzer
-	if req.Email == "test@localhost.de" {
-		token, err := CreateJWT("system-user-id", req.Email, "admin", time.Hour*24*7)
-		if err != nil {
-			c.JSON(http.StatusInternalServerError, gin.H{"error": "Token error"})
-			return
-		}
-		c.JSON(http.StatusOK, LoginResponse{Token: token})
+	// Validate input
+	if req.Email == "" || req.Password == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Email and password are required"})
 		return
 	}

-	c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid credentials"})
+	// Systemnutzer
+	var token string
+	var err error
+	if req.Email == "test@localhost.de" {
+		token, err = CreateJWT("system-user-id", req.Email, "admin", 60*time.Minute)
+	} else {
+
+		hash, err := common.HashPassword(req.Password)
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "Password hashing error"})
+			return
+		}
+
+		loggedInPlayer, err := player.LoginPlayer(db, req.Email, string(hash))
+		if err != nil {
+			if err == sql.ErrNoRows {
+				c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid credentials"})
+				return
+			}
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "Database error"})
+			return
+		}
+		// Create JWT token
+		token, err = CreateJWT(loggedInPlayer.ID, req.Email, "player", 60*time.Minute)
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "Token creation error"})
+			return
+		}
+	}
+
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Token error"})
+		return
+	}
+	c.JSON(http.StatusOK, LoginResponse{Token: token})
+	return
 }
--- a/backend/internal/common/passwordHasher.go
+++ b/backend/internal/common/passwordHasher.go
@@ -0,0 +1,12 @@
+package common
+
+import "golang.org/x/crypto/bcrypt"
+
+func HashPassword(password string) (string, error) {
+	// Use bcrypt to hash the password
+	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		return "", err
+	}
+	return string(hashedPassword), nil
+}
--- a/backend/internal/database/database.go
+++ b/backend/internal/database/database.go
@@ -17,6 +17,29 @@ type database struct {
 	db       *sql.DB // Pointer to sql.DB
 }

+func (d *database) SetupTables() error {
+	InitTables(d.db)
+	log.Println("Database setup completed successfully.")
+	return nil
+}
+
+func (d *database) GetDB() *sql.DB {
+	if d.db == nil {
+		log.Println("Database connection is not established. Call Connect() first.")
+		return nil
+	}
+	return d.db
+}
+
+// New creates a new database instance with the provided configuration.
+// It initializes the database connection parameters but does not connect to the database.
+// This function should be called before calling Connect() to establish the connection.
+// It returns a pointer to the database instance.
+// Example usage:
+// db := database.New("localhost", 5432, "user", "password", "dbname")
+// It is intended to be used in the main application or setup phase.
+// This function is not intended to be called during normal application operation.
+// It is not intended to be called during normal application operation.
 func New(host string, port int, user, password, dbname string) *database {
 	return &database{
 		host:     host,
@@ -28,7 +51,7 @@ func New(host string, port int, user, password, dbname string) *database {
 	}
 }

-func (d *database) Connect() error {
+func (d *database) Connect() (db *sql.DB) {
 	fmt.Println("Connecting to the database...")
 	psqlInfo := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=disable",
 		d.host, d.port, d.user, d.password, d.dbname)
@@ -49,5 +72,5 @@ func (d *database) Connect() error {

 	log.Println("Connected to the database successfully")
 	d.db = db
-	return nil
+	return db
 }
--- a/backend/internal/database/initTables.go
+++ b/backend/internal/database/initTables.go
@@ -5,28 +5,66 @@ import (
 	"fmt"
 	"log"

+	"volleyball/internal/player"
+
 	_ "github.com/lib/pq" // Import the PostgreSQL driver
 )

-const playerTable = `
-	CREATE TABLE IF NOT EXISTS players (
+const teamTable = `
+	CREATE TABLE IF NOT EXISTS teams (
 		id SERIAL PRIMARY KEY,
-		name VARCHAR(100) NOT NULL,
-		age INT NOT NULL,
-		birthday DATE NOT NULL
+		player1_id uuid NOT NULL,	
+		player2_id uuid NOT NULL,
+		formation_date DATE NOT NULL DEFAULT CURRENT_DATE,
+		FOREIGN KEY (player1_id) REFERENCES players(id),
+		FOREIGN KEY (player2_id) REFERENCES players(id)
 	);
 `

-func InitTables(db *sql.DB) {
+var tableNames = []string{
+	"players",
+	"teams",
+}
+
+func CheckIfTablesExist(db *sql.DB) (bool, error) {
+	for _, tableName := range tableNames {
+		exists, err := tableExists(db, tableName)
+		if err != nil {
+			return false, fmt.Errorf("error checking if table %s exists: %w", tableName, err)
+		}
+		if !exists {
+			return false, nil // At least one table does not exist
+		}
+	}
+	return true, nil // All tables exist
+}
+
+func tableExists(db *sql.DB, tableName string) (bool, error) {
+	query := `
+		SELECT EXISTS (
+			SELECT FROM information_schema.tables 
+			WHERE table_schema = 'public' AND table_name = $1
+		);
+	`
+	var exists bool
+	err := db.QueryRow(query, tableName).Scan(&exists)
+	return exists, err
+}
+
+func InitTables(d *sql.DB) error {
 	tables := []string{
-		playerTable,
+		player.PlayerTable,
+		player.RoleTable,
+		teamTable,
 	}

 	for _, table := range tables {
-		if _, err := db.Exec(table); err != nil {
+		if _, err := d.Exec(table); err != nil {
 			log.Fatalf("Error creating table: %v", err)
+			return fmt.Errorf("error creating table: %w", err)
 		}
 	}

-	fmt.Println("Tables initialized successfully.")
+	log.Println("Tables initialized successfully.")
+	return nil
 }
--- a/backend/internal/player/handler.go
+++ b/backend/internal/player/handler.go
@@ -0,0 +1,145 @@
+package player
+
+import (
+	"database/sql"
+	"log"
+	"net/http"
+	"volleyball/internal/common"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+)
+
+func GetPlayers(c *gin.Context, db *sql.DB) {
+	log.Println(c.GetString("userId"), c.GetString("email"), c.GetString("role"))
+	// Simulate fetching players from a database
+
+	players, err := GetAllPlayers(db)
+	if err != nil {
+		log.Printf("Error retrieving players: %v", err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to retrieve players")
+		return
+	}
+
+	if len(players) > 0 {
+		log.Printf("User %s (%s) requested players", c.GetString("userId"), c.GetString("email"))
+		c.JSON(http.StatusOK, players)
+		return
+	}
+	log.Printf("User %s (%s) requested players, but none found", c.GetString("userId"), c.GetString("email"))
+
+	common.RespondError(c, http.StatusNotFound, "No Players found")
+}
+
+func CreatePlayer(c *gin.Context, db *sql.DB) {
+	var newPlayer Player
+	var err error
+	if err := c.ShouldBindJSON(&newPlayer); err != nil {
+		log.Printf("Error binding player data: %v", err)
+		common.RespondError(c, http.StatusBadRequest, "Invalid player data")
+		return
+	}
+	newPlayer.Password, err = common.HashPassword(newPlayer.Password)
+	if err != nil {
+		log.Printf("Error hashing password: %v", err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to hash password")
+		return
+	}
+
+	newPlayer.ID = uuid.New().String()
+	err = savePlayer(db, newPlayer)
+	if err != nil {
+		log.Printf("Error saving player: %v", err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to create player")
+		return
+	}
+	AddRoleToPlayer(db, newPlayer.ID, "player")
+	if err != nil {
+		log.Printf("Error adding role to player: %v", err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to assign role to player")
+		return
+	}
+
+	log.Printf("User %s (%s) created player: %s", c.GetString("userId"), c.GetString("email"), newPlayer.Name)
+
+	common.RespondCreated(c, newPlayer)
+}
+
+func GetPlayer(c *gin.Context, db *sql.DB) {
+	playerID := c.Param("id")
+	if playerID == "" {
+		common.RespondError(c, http.StatusBadRequest, "Player ID is required")
+		return
+	}
+
+	player, err := GetPlayerByID(db, playerID)
+	if err != nil {
+		log.Printf("Error retrieving player with ID %s: %v", playerID, err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to retrieve player")
+		return
+	}
+
+	if player.ID == "" {
+		log.Printf("Player with ID %s not found", playerID)
+		common.RespondError(c, http.StatusNotFound, "Player not found")
+		return
+	}
+
+	log.Printf("User %s (%s) requested player: %s", c.GetString("userId"), c.GetString("email"), player.Name)
+
+	c.JSON(http.StatusOK, player)
+}
+
+func UpdatePlayer(c *gin.Context, db *sql.DB) {
+	playerID := c.Param("id")
+	if playerID == "" {
+		common.RespondError(c, http.StatusBadRequest, "Player ID is required")
+		return
+	}
+
+	if playerID != c.GetString("userId") || c.GetString("role") != "admin" {
+		common.RespondError(c, http.StatusForbidden, "You do not have permission to update this player")
+		return
+	}
+
+	var updatedPlayer Player
+	if err := c.ShouldBindJSON(&updatedPlayer); err != nil {
+		log.Printf("Error binding player data: %v", err)
+		common.RespondError(c, http.StatusBadRequest, "Invalid player data")
+		return
+	}
+
+	updatedPlayer.ID = playerID
+	err := updatePlayer(db, updatedPlayer)
+	if err != nil {
+		log.Printf("Error updating player with ID %s: %v", playerID, err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to update player")
+		return
+	}
+
+	log.Printf("User %s (%s) updated player: %s", c.GetString("userId"), c.GetString("email"), updatedPlayer.Name)
+
+	c.JSON(http.StatusOK, updatedPlayer)
+}
+func DeletePlayer(c *gin.Context, db *sql.DB) {
+	playerID := c.Param("id")
+	if playerID == "" {
+		common.RespondError(c, http.StatusBadRequest, "Player ID is required")
+		return
+	}
+	if c.GetString("role") != "admin" {
+		common.RespondError(c, http.StatusForbidden, "You do not have permission to delete this player")
+		return
+	}
+
+	err := deletePlayer(db, playerID)
+	if err != nil {
+		log.Printf("Error deleting player with ID %s: %v", playerID, err)
+		common.RespondError(c, http.StatusInternalServerError, "Failed to delete player")
+		return
+	}
+
+	log.Printf("User %s (%s) deleted player with ID: %s", c.GetString("userId"), c.GetString("email"), playerID)
+
+	common.RespondMessage(c, "Player deleted successfully")
+}
--- a/backend/internal/player/model.go
+++ b/backend/internal/player/model.go
@@ -0,0 +1,286 @@
+package player
+
+import (
+	"database/sql"
+	"log"
+
+	"github.com/google/uuid"
+)
+
+const PlayerTable = `
+	CREATE TABLE IF NOT EXISTS players (
+		id uuid PRIMARY KEY,
+		name VARCHAR(100) NOT NULL,
+		email VARCHAR(100) NOT NULL UNIQUE,
+		password_hash VARCHAR(255) NOT NULL
+	);
+	`
+const RoleTable = `
+	CREATE TABLE IF NOT EXISTS roles (
+		id SERIAL PRIMARY KEY,
+		player_id uuid NOT NULL,
+		role VARCHAR(50) NOT NULL CHECK (role IN ('player', 'admin')),
+		FOREIGN KEY (player_id) REFERENCES players(id) ON DELETE CASCADE
+	);
+`
+
+type Team struct {
+	ID      string   `json:"id"`
+	Name    string   `json:"name"`
+	Players []Player `json:"players"` // Players in the team
+	// Matches            []Match  `json:"matches"`            // Matches the team is involved in
+	MatchesWon         int `json:"matchesWon"`         // Number of matches won by the team
+	MatchesLost        int `json:"matchesLost"`        // Number of matches lost by the team
+	MatchesDrawn       int `json:"matchesDrawn"`       // Number of matches drawn by the team
+	MatchesPlayed      int `json:"matchesPlayed"`      // Total matches played by the team
+	MatchesPlayedCount int `json:"matchesPlayedCount"` // Total matches played by the team
+}
+
+type Player struct {
+	ID       string `json:"id"`
+	Name     string `json:"name"`
+	Email    string `json:"email"`
+	Password string `json:"password,omitempty"` // Password is optional for responses
+	Role     string `json:"role"`               // e.g., "player","organizer"
+	Teams    []Team `json:"teams"`              // Teams the player is part of
+	// Tournaments        []Tournament `json:"tournaments"`        // Tournaments the player is registered in
+	OwnedTournaments        []string `json:"ownedTournaments"`        // Tournaments the player is organizing
+	ParticipatedTournaments []string `json:"participatedTournaments"` // Tournaments the player is participating in
+}
+type PlayerListResponse struct {
+	Players []Player `json:"players"`
+}
+type PlayerResponse struct {
+	Player Player `json:"player"`
+}
+type CreatePlayerRequest struct {
+	Name  string `json:"name" binding:"required"`
+	Email string `json:"email" binding:"required,email"`
+	Role  string `json:"role" binding:"required,oneof=player organizer"`
+}
+type UpdatePlayerRequest struct {
+	Name  string `json:"name" binding:"required"`
+	Email string `json:"email" binding:"required,email"`
+	Role  string `json:"role" binding:"required,oneof=player organizer"`
+	Teams []Team `json:"teams"` // Teams the player is part of
+}
+type DeletePlayerRequest struct {
+	ID string `json:"id" binding:"required"`
+}
+type PlayerService interface {
+	CreatePlayer(req CreatePlayerRequest) (Player, error)
+	GetPlayer(id string) (Player, error)
+	UpdatePlayer(id string, req UpdatePlayerRequest) (Player, error)
+	DeletePlayer(id string) error
+	ListPlayers() ([]Player, error)
+	GetPlayerTeams(id string) ([]Team, error)
+	GetPlayerByEmail(email string) (Player, error)
+	GetPlayerByName(name string) (Player, error)
+	GetPlayerByID(id string) (Player, error)
+	GetPlayerByRole(role string) ([]Player, error)
+	GetPlayerByTeam(teamID string) ([]Player, error)
+	GetPlayerByTournament(tournamentID string) ([]Player, error)
+	GetPlayerByOrganizer(organizerID string) ([]Player, error)
+}
+
+func LoginPlayer(db *sql.DB, email, password string) (Player, error) {
+	var player Player
+	var playerPassword string
+	err := db.QueryRow("SELECT id, name, email, password FROM players WHERE email = $1", email).Scan(&player.ID, &player.Name, &player.Email, playerPassword)
+	if err != nil {
+		log.Printf("Error logging in player with email %s: %v", email, err)
+		return Player{}, err
+	}
+	if player.ID == "" {
+		log.Printf("Player with email %s not found", email)
+		return Player{}, sql.ErrNoRows // or a custom error
+	}
+	// Check if the password matches
+	if password == playerPassword {
+		log.Printf("Player %s logged in successfully", player.Name)
+	}
+
+	log.Printf("Player %s logged in successfully", player.Name)
+	return player, nil
+}
+
+func GetPlayerRole(db *sql.DB, playerID string) (string, error) {
+	var role string
+	err := db.QueryRow("SELECT role FROM roles WHERE player_id = $1", playerID).Scan(&role)
+	if err != nil {
+		log.Printf("Error retrieving role for player ID %s: %v", playerID, err)
+		return "", err
+	}
+	if role == "" {
+		log.Printf("No role found for player ID %s", playerID)
+		return "", sql.ErrNoRows // or a custom error
+	}
+	log.Printf("Retrieved role for player ID %s: %s", playerID, role)
+	return role, nil
+}
+
+func savePlayer(db *sql.DB, player Player) error {
+
+	// Ensure the player ID is set
+	if player.ID == "" {
+		player.ID = uuid.New().String() // Generate a new UUID if not set
+		log.Printf("Generated new player ID: %s", player.ID)
+	}
+	// Insert the player into the database
+	if player.Role == "" {
+		player.Role = "player" // Default role if not specified
+		log.Printf("Setting default role for player %s to 'player'", player.Name)
+	}
+
+	log.Printf("Saving player: ID=%v, Name=%v, Email=%v", player.ID, player.Name, player.Email)
+
+	stmt := "INSERT INTO public.players (id, name, email) VALUES ($1, $2, $3)"
+	log.Printf("Generated SQL statement: %s", stmt)
+	_, err := db.Exec(stmt, player.ID, player.Name, player.Email)
+
+	if err != nil {
+		log.Printf("Error saving player to database: %v", err)
+	}
+	// lastID, err := res.LastInsertId()
+	// if err != nil {
+	// 	log.Printf("Error getting last insert ID: %v", err)
+	// } else {
+	// 	log.Printf("Last insert ID: %d", lastID)
+	// }
+	// if err := db.QueryRow("SELECT id, name, email FROM players WHERE id = ?", player.ID).Scan(&player.ID, &player.Name, &player.Email, &player.Role); err != nil {
+	// 	log.Printf("Error retrieving player from database: %v", err)
+	// 	return err
+	// }
+	log.Printf("Player %s saved to database", player.Name)
+	return nil
+}
+
+func AddRoleToPlayer(db *sql.DB, playerID, role string) error {
+	if playerID == "" {
+		log.Printf("Player ID is required to add a role, but got empty ID")
+		return sql.ErrNoRows // or a custom error
+	}
+
+	log.Printf("Adding role '%s' to player with ID: %s", role, playerID)
+
+	stmt := "INSERT INTO public.roles (player_id, role) VALUES ($1, $2)"
+	_, err := db.Exec(stmt, playerID, role)
+	if err != nil {
+		log.Printf("Error adding role to player with ID %s: %v", playerID, err)
+		return err
+	}
+
+	log.Printf("Role '%s' added to player with ID %s successfully", role, playerID)
+	return nil
+}
+
+func GetAllPlayers(db *sql.DB) ([]Player, error) {
+	rows, err := db.Query("SELECT id, name, email FROM public.players")
+	if err != nil {
+		log.Printf("Error retrieving players: %v", err)
+		return nil, err
+	}
+	defer rows.Close()
+
+	var players []Player
+	for rows.Next() {
+		var player Player
+		if err := rows.Scan(&player.ID, &player.Name, &player.Email); err != nil {
+			log.Printf("Error scanning player row: %v", err)
+			return nil, err
+		}
+		players = append(players, player)
+	}
+
+	if err := rows.Err(); err != nil {
+		log.Printf("Error iterating over player rows: %v", err)
+		return nil, err
+	}
+
+	return players, nil
+}
+
+func GetPlayerByID(db *sql.DB, id string) (Player, error) {
+	var player Player
+	err := db.QueryRow("SELECT id, name, email FROM players WHERE id = $1", id).Scan(&player.ID, &player.Name, &player.Email, &player.Role)
+	if err != nil {
+		log.Printf("Error retrieving player by ID %s: %v", id, err)
+		return Player{}, err
+	}
+	return player, nil
+}
+func GetPlayerByEmail(db *sql.DB, email string) (Player, error) {
+	var player Player
+	err := db.QueryRow("SELECT id, name, email FROM players WHERE email = $1", email).Scan(&player.ID, &player.Name, &player.Email, &player.Role)
+	if err != nil {
+		log.Printf("Error retrieving player by email %s: %v", email, err)
+		return Player{}, err
+	}
+	return player, nil
+}
+func GetPlayerByName(db *sql.DB, name string) (Player, error) {
+	var player Player
+	err := db.QueryRow("SELECT id, name, email FROM players WHERE name = $1", name).Scan(&player.ID, &player.Name, &player.Email, &player.Role)
+	if err != nil {
+		log.Printf("Error retrieving player by name %s: %v", name, err)
+		return Player{}, err
+	}
+	return player, nil
+}
+
+// DeletePlayer deletes a player from the database by ID.
+func deletePlayer(db *sql.DB, id string) error {
+	// Delete the player from the database
+	log.Printf("Deleting player with ID: %s", id)
+	_, err := db.Exec("DELETE FROM public.players WHERE id = $1", id)
+	if err != nil {
+		log.Printf("Error deleting player with ID %s: %v", id, err)
+		return err
+	}
+	log.Printf("Player with ID %s deleted successfully", id)
+	return nil
+}
+
+// UpdatePlayer updates an existing player in the database.
+// It requires the player ID to be set in the Player struct.
+func updatePlayer(db *sql.DB, player Player) error {
+	// Ensure the player ID is set
+	if player.ID == "" {
+		log.Printf("Player ID is required for update, but got empty ID")
+		return sql.ErrNoRows // or a custom error
+	}
+
+	log.Printf("Updating player: ID=%v, Name=%v, Email=%v", player.ID, player.Name, player.Email)
+
+	stmt := "UPDATE public.players SET name = $1, email = $2 WHERE id = $3"
+	_, err := db.Exec(stmt, player.Name, player.Email, player.ID)
+	if err != nil {
+		log.Printf("Error updating player in database: %v", err)
+		return err
+	}
+
+	log.Printf("Player %s updated successfully", player.Name)
+	return nil
+}
+
+var players_default = []Player{{
+	ID:    "1",
+	Name:  "John Doe",
+	Email: "John.Doe@example.de",
+	Role:  "player",
+	Teams: []Team{
+		{ID: "team1"},
+		{ID: "team2"},
+	},
+},
+	{
+		ID:    "2",
+		Name:  "Jane Smith",
+		Email: "Jane-Smith@example.de",
+		Role:  "player",
+		Teams: []Team{
+			{ID: "team3"},
+			{ID: "team1"},
+		},
+	},
+}
--- a/backend/internal/tournament/handler.go
+++ b/backend/internal/tournament/handler.go
@@ -4,6 +4,8 @@ import (
 	"net/http"
 	"volleyball/internal/common"

+	"slices"
+
 	"github.com/gin-gonic/gin"
 )

@@ -17,7 +19,7 @@ var tournaments = []Tournament{
 			{ID: "t1", Name: "Smasher"},
 			{ID: "t2", Name: "Blockbuster"},
 		},
-		OrganizerId: "system-user-id",
+		OrganizerId: []string{"example-user"},
 	},
 	{
 		ID:              "2",
@@ -25,7 +27,7 @@ var tournaments = []Tournament{
 		Location:        "Hamburg",
 		MaxParticipants: 10,
 		Teams:           []Team{},
-		OrganizerId:     "other-user",
+		OrganizerId:     []string{"example-user"},
 	},
 }

@@ -74,7 +76,8 @@ func UpdateTournament(c *gin.Context) {

 	for i, t := range tournaments {
 		if t.ID == id {
-			if t.OrganizerId != userId {
+			isOrganizer := slices.Contains(t.OrganizerId, userId)
+			if !isOrganizer {
 				c.JSON(http.StatusForbidden, gin.H{"error": "No permission"})
 				return
 			}
--- a/backend/internal/tournament/model.go
+++ b/backend/internal/tournament/model.go
@@ -6,10 +6,10 @@ type Team struct {
 }

 type Tournament struct {
-	ID              string `json:"id"`
-	Name            string `json:"name"`
-	Location        string `json:"location"`
-	MaxParticipants int    `json:"maxParticipants"`
-	Teams           []Team `json:"teams"`
-	OrganizerId     string `json:"organizerId"`
+	ID              string   `json:"id"`
+	Name            string   `json:"name"`
+	Location        string   `json:"location"`
+	MaxParticipants int      `json:"maxParticipants"`
+	Teams           []Team   `json:"teams"`
+	OrganizerId     []string `json:"PlayerId"` // List of player IDs who are organizers
 }