nightclub-arcadia/NightclubArcadia/Assets/Editor/YarnDemoSetup.cs

using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.EventSystems;
using Yarn.Compiler;
using Yarn.Unity;
using Yarn.Unity.Editor;

public static class YarnDemoSetup
{
    const string YarnProjectPath = "Assets/Dialogue/NightclubArcadia.yarnproject";
    const string ScenePath = NightclubArcadia.EditorTools.ScenePaths.Sandbox;

    [MenuItem("Tools/Nightclub Arcadia/Set Up Yarn Sandbox Scene")]
    public static void SetUpYarnDialogueTest()
    {
        if (NightclubArcadia.EditorTools.LegacySceneSetup.Blocked("Set Up Yarn Sandbox Scene",
            "generate a throwaway scene whose dialogue runner duplicates the real one")) return;

        // This menu BUILDS A SCENE FROM SCRATCH and saves over ScenePath. Pointed at a
        // real level it silently destroys it, which is exactly what happened when it
        // was briefly retargeted at SC101_ConferenceHall. The guard is the fix; do not
        // remove it, and do not point ScenePath outside Scenes/Dev.
        if (!NightclubArcadia.EditorTools.ScenePaths.IsDisposable(ScenePath))
        {
            Debug.LogError($"Refusing to run: '{ScenePath}' is not under Assets/Scenes/Dev/. " +
                           "This menu overwrites its target scene wholesale.");
            return;
        }

        if (!AssetDatabase.IsValidFolder("Assets/Scenes/Dev"))
        {
            AssetDatabase.CreateFolder("Assets/Scenes", "Dev");
        }

        if (!AssetDatabase.IsValidFolder("Assets/TextMesh Pro"))
        {
            Debug.LogWarning("TextMesh Pro essential resources are missing. Run Window → TextMeshPro → Import TMP Essential Resources.");
        }

        if (!AssetDatabase.IsValidFolder("Assets/Dialogue"))
        {
            AssetDatabase.CreateFolder("Assets", "Dialogue");
        }

        if (!AssetDatabase.IsValidFolder("Assets/Scenes"))
        {
            AssetDatabase.CreateFolder("Assets", "Scenes");
        }

        var yarnProject = AssetDatabase.LoadAssetAtPath<YarnProject>(YarnProjectPath);
        if (yarnProject == null)
        {
            // YarnProjectUtility.CreateDefaultYarnProject is internal, so
            // construct the same default project here.
            var project = new Project
            {
                ExcludeFilePatterns = new[] { "**/*~/*", "./Samples/Yarn Spinner*/*" },
            };
            YarnEditorUtility.CreateYarnProject(YarnProjectPath, project);
            AssetDatabase.Refresh();
            yarnProject = AssetDatabase.LoadAssetAtPath<YarnProject>(YarnProjectPath);
        }

        var scene = EditorSceneManager.NewScene(NewSceneSetup.DefaultGameObjects, NewSceneMode.Single);

        var runner = CreateDialogueRunnerMenuItem.CreateDialogueRunner();

        var so = new SerializedObject(runner);
        so.FindProperty("yarnProject").objectReferenceValue = yarnProject;
        so.ApplyModifiedPropertiesWithoutUndo();

        // CreateDialogueRunner returns a component on a PREFAB INSTANCE of the package's
        // Dialogue System prefab. Applying a SerializedProperty on one of those does not
        // always record the override, and an unrecorded override is dropped on save —
        // which produced a sandbox whose runner had no project, auto-started, and
        // failed with "Can't start dialogue: no Yarn Project has been configured."
        if (PrefabUtility.IsPartOfPrefabInstance(runner))
        {
            PrefabUtility.RecordPrefabInstancePropertyModifications(runner);
        }

        runner.autoStart = true;
        runner.startNode = "Start";
        EditorUtility.SetDirty(runner);
        EditorSceneManager.MarkSceneDirty(scene);

        // Postcondition. This menu exists to produce a runnable scene; a scene whose
        // runner has no project is worse than no scene, because it fails at Play time
        // with an error that points nowhere near here.
        if (new SerializedObject(runner).FindProperty("yarnProject").objectReferenceValue == null)
        {
            Debug.LogError("Yarn sandbox setup failed: the DialogueRunner has no Yarn Project. " +
                           "The generated scene will error on Play. Not saving.");
            return;
        }

#if UNITY_2023_1_OR_NEWER
        var eventSystems = Object.FindObjectsByType<EventSystem>(FindObjectsInactive.Include);
#else
        var eventSystems = Object.FindObjectsOfType<EventSystem>(true);
#endif
        foreach (var eventSystem in eventSystems)
        {
            if (eventSystem.GetComponent<BaseInputModule>() != null)
            {
                continue;
            }

#if ENABLE_INPUT_SYSTEM
            eventSystem.gameObject.AddComponent<UnityEngine.InputSystem.UI.InputSystemUIInputModule>();
#endif
        }

        EditorSceneManager.SaveScene(scene, ScenePath);
        AssetDatabase.SaveAssets();

        Debug.Log($"Yarn dialogue test setup complete. Scene saved to {ScenePath}");
    }
}