using UnityEditor;
using UnityEngine;
using System;

// Create an editor window which can display a chosen GameObject.
// Use OnInteractivePreviewGUI to display the GameObject and
// allow it to be interactive.

public class PreviewSpriteMaker : EditorWindow {
	private static GameObject gameObject;
	private static Editor gameObjectEditor;
	Vector2Int resolution = new Vector2Int(128,128);
	readonly string[] options_s = new string[] {"16","32","64","128","256","512"};
	readonly int[] options_i = new int[] {16,32,64,128,256,512};

	[MenuItem("Window/Preview Sprite Maker")]
	static void ShowWindow() {
		GetWindow<PreviewSpriteMaker>(true, "Preview Sprite Maker", true);
	}

	void OnGUI() {
		EditorGUI.BeginChangeCheck();
		GUILayout.BeginHorizontal();
		resolution.x = EditorGUILayout.IntPopup(resolution.x,options_s,options_i);
		resolution.y = EditorGUILayout.IntPopup(resolution.y,options_s,options_i);

		EditorGUI.BeginDisabledGroup(gameObjectEditor == null);
		if (GUILayout.Button("Save")) {
			Texture2D tex = gameObjectEditor.RenderStaticPreview("", null, resolution.x,resolution.y);
			Sprite sprite = Sprite.Create(tex, new Rect(0,0,resolution.x,resolution.y), Vector2.zero);
		 	string path = EditorUtility.SaveFilePanelInProject("Save Sprite","NewSprite", "asset", "");
			AssetDatabase.CreateAsset(tex, path);
		}
		EditorGUI.EndDisabledGroup();
		GUILayout.EndHorizontal();
		if (EditorGUI.EndChangeCheck()) {
			Rect pos = position;
			pos.width = Mathf.Max(pos.width, resolution.x);
			pos.height = Mathf.Max(pos.height, resolution.y);
			position = pos;
		}

		GUIStyle bgColor = new GUIStyle();
		bgColor.normal.background = EditorGUIUtility.whiteTexture;

		if (Selection.activeGameObject != null) {
			if (gameObjectEditor == null || Selection.activeGameObject != gameObject) {
				gameObjectEditor = Editor.CreateEditor(Selection.activeGameObject);
				gameObject = Selection.activeGameObject;
			}
			gameObjectEditor.OnPreviewGUI(GUILayoutUtility.GetRect(resolution.x, resolution.y, GUILayout.Width(resolution.x), GUILayout.Height(resolution.y)), bgColor);
		} else {
			gameObjectEditor = null;
		}
	}
}