package user_service

import (
	"testing"
)

// TestUserService acts as the main entry point for testing all UserService functionalities.
// It demonstrates how to group tests for different methods using t.Run.
func TestUserService(t *testing.T) {
	// Optional: Common setup for all UserService tests can go here.
	t.Log("Starting tests for UserService...")

	// --- Group for CreateUser method tests ---
	t.Run("CreateUser", func(t *testing.T) {
		t.Log("  Running CreateUser tests...")

		// Sub-case 1 for CreateUser: Valid input
		t.Run("ValidInput", func(t *testing.T) {
			// t.Parallel() // This specific case could run in parallel with other CreateUser cases.
			userService := NewUserService() // Fresh instance for isolation
			_, err := userService.CreateUser("user123", "Alice")
			if err != nil {
				t.Errorf("CreateUser with valid input failed: %v", err)
			}
			// Add more specific assertions if needed, but focus here is on structure.
			t.Log("    CreateUser/ValidInput: PASSED (simulated)")
		})

		// Sub-case 2 for CreateUser: Invalid input (e.g., empty ID)
		t.Run("EmptyID", func(t *testing.T) {
			userService := NewUserService()
			_, err := userService.CreateUser("", "Bob")
			if err == nil {
				t.Error("CreateUser with empty ID should have failed, but got nil error")
			}
			t.Log("    CreateUser/EmptyID: PASSED (simulated error check)")
		})

		// Add more t.Run calls for other CreateUser scenarios (e.g., duplicate ID)
	})

	// --- Group for GetUser method tests ---
	t.Run("GetUser", func(t *testing.T) {
		t.Log("  Running GetUser tests...")
		userService := NewUserService()
		userService.CreateUser("userExists", "Charlie")

		// Sub-case 1 for GetUser: Existing user
		t.Run("ExistingUser", func(t *testing.T) {
			// t.Parallel()
			_, err := userService.GetUser("userExists")
			if err != nil {
				t.Errorf("GetUser for existing user failed: %v", err)
			}
			t.Log("    GetUser/ExistingUser: PASSED (simulated)")
		})

		// Sub-case 2 for GetUser: Non-existing user
		t.Run("NonExistingUser", func(t *testing.T) {
			// t.Parallel()
			_, err := userService.GetUser("userDoesNotExist")
			if err == nil {
				t.Error("GetUser for non-existing user should have failed, but got nil error")
			}
			t.Log("    GetUser/NonExistingUser: PASSED (simulated error check)")
		})
	})

	// --- Group for UpdateUser method tests (Illustrative) ---
	t.Run("UpdateUser", func(t *testing.T) {
		t.Log("  Running UpdateUser tests (structure demonstration)...")
		t.Run("ValidUpdate", func(t *testing.T) {
			userService := NewUserService()
			userService.CreateUser("userToUpdate", "OldName")
			err := userService.UpdateUser("userToUpdate", "NewName")
			if err != nil {
				t.Errorf("UpdateUser failed: %v", err)
			}
			t.Log("    UpdateUser/ValidUpdate: PASSED (simulated)")
		})
	})

	t.Log("Finished tests for UserService.")
}
