ATOM-15228 Updated the AtomSampleViewer project root CMakeLists.txt to work as a top level CMake project

CMakeLists.txt

@@ -9,13 +9,38 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #
 
-file(READ "${CMAKE_CURRENT_LIST_DIR}/project.json" project_json)
+#! Adds the --project-path argument to the VS IDE debugger command arguments
+function(add_vs_debugger_arguments)
+    # Inject the project root into the --project-path argument into the Visual Studio Debugger arguments by defaults
+    list(APPEND app_targets AtomSampleViewer.GameLauncher AtomSampleViewer.ServerLauncher)
+    list(APPEND app_targets AssetBuilder AssetProcessor AssetProcessorBatch Editor)
+    foreach(app_target IN LISTS app_targets)
+        if (TARGET ${app_target})
+            set_property(TARGET ${app_target} APPEND PROPERTY VS_DEBUGGER_COMMAND_ARGUMENTS "--project-path=\"${CMAKE_CURRENT_LIST_DIR}\"")
+        endif()
+    endforeach()
+endfunction()
 
-string(JSON project_target_name ERROR_VARIABLE json_error GET ${project_json} "project_name")
-if(${json_error})
-    message(FATAL_ERROR "Unable to read key 'project_name' from 'project.json'")
-endif()
+if(NOT PROJECT_NAME)
+    cmake_minimum_required(VERSION 3.19)
+    project(AtomSampleViewer
+        LANGUAGES C CXX
+        VERSION 1.0.0.0
+    )
+    include(EngineFinder.cmake OPTIONAL)
+    find_package(o3de REQUIRED)
+    o3de_initialize()
+    add_vs_debugger_arguments()
+else()
+    # Add the project_name to global LY_PROJECTS_TARGET_NAME property
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/project.json" project_json)
 
-set_property(GLOBAL APPEND PROPERTY LY_PROJECTS_TARGET_NAME ${project_target_name})
-add_subdirectory(Gem)
-add_subdirectory(Standalone)
+    string(JSON project_target_name ERROR_VARIABLE json_error GET ${project_json} "project_name")
+    if(json_error)
+        message(FATAL_ERROR "Unable to read key 'project_name' from 'project.json'")
+    endif()
+
+    set_property(GLOBAL APPEND PROPERTY LY_PROJECTS_TARGET_NAME ${project_target_name})
+
+    add_subdirectory(Gem)
+endif()