using UnityEngine;
using UnityEditor;
using System.Collections.Generic;
using ProBuilder2.EditorCommon;	// pb_Editor and pb_EditorUtility
using ProBuilder2.Interface;	// pb_GUI_Utility
using ProBuilder2.Common;		// EditLevel
using System.Linq;				// Sum()

class EditorCallbackViewer : EditorWindow
{
	[MenuItem("Tools/" + pb_Constant.PRODUCT_NAME + "/API Examples/Log Callbacks Window")]
	static void MenuInitEditorCallbackViewer()
	{
		EditorWindow.GetWindow<EditorCallbackViewer>(true, "ProBuilder Callbacks", true).Show();
	}

	List<string> logs = new List<string>();
	Vector2 scroll = Vector2.zero;
	bool collapse = true;

	static Color logBackgroundColor
	{
		get
		{
			return EditorGUIUtility.isProSkin ? new Color(.15f, .15f, .15f, .5f) : new Color(.8f, .8f, .8f, 1f);
		}
	}

	static Color disabledColor
	{
		get
		{
			return EditorGUIUtility.isProSkin ? new Color(.3f, .3f, .3f, .5f) : new Color(.8f, .8f, .8f, 1f);
		}
	}

	void OnEnable()
	{
		// Delegate for Top/Geometry/Texture mode changes.
		pb_Editor.AddOnEditLevelChangedListener(OnEditLevelChanged);

		// Called when a new ProBuilder object is created.
		// note - this was added in ProBuilder 2.5.1
		pb_EditorUtility.AddOnObjectCreatedListener(OnProBuilderObjectCreated);

		// Called when the ProBuilder selection changes (can be object or element change).
		// Also called when the geometry is modified by ProBuilder.
		pb_Editor.OnSelectionUpdate += OnSelectionUpdate;

		// Called when vertices are about to be modified.
		pb_Editor.OnVertexMovementBegin += OnVertexMovementBegin;

		// Called when vertices have been moved by ProBuilder.
		pb_Editor.OnVertexMovementFinish += OnVertexMovementFinish;

		// Called when the Unity mesh is rebuilt from ProBuilder mesh data.
		pb_EditorUtility.AddOnMeshCompiledListener(OnMeshCompiled);		
	}

	void OnDisable()
	{
		pb_Editor.RemoveOnEditLevelChangedListener(OnEditLevelChanged);
		pb_EditorUtility.RemoveOnObjectCreatedListener(OnProBuilderObjectCreated);
		pb_EditorUtility.RemoveOnMeshCompiledListener(OnMeshCompiled);
		pb_Editor.OnSelectionUpdate -= OnSelectionUpdate;
		pb_Editor.OnVertexMovementBegin -= OnVertexMovementBegin;
		pb_Editor.OnVertexMovementFinish -= OnVertexMovementFinish;
	}

	void OnProBuilderObjectCreated(pb_Object pb)
	{
		AddLog("Instantiated new ProBuilder Object: " + pb.name);
	}

	void OnEditLevelChanged(int editLevel)
	{
		AddLog("Edit Level Changed: " + (EditLevel) editLevel);
	}

	void OnSelectionUpdate(pb_Object[] selection)
	{
		AddLog("Selection Updated: " + string.Format("{0} objects and {1} vertices selected.",
			selection != null ? selection.Length : 0,
			selection != null ? selection.Sum(x => x.SelectedTriangleCount) : 0));
	}

	void OnVertexMovementBegin(pb_Object[] selection)
	{
		AddLog("Began Moving Vertices");
	}

	void OnVertexMovementFinish(pb_Object[] selection)
	{
		AddLog("Finished Moving Vertices");
	}
	
	void OnMeshCompiled(pb_Object pb, Mesh mesh)
	{
		AddLog(string.Format("Mesh {0} rebuilt", pb.name));
	}

	void AddLog(string summary)
	{
		logs.Add(summary);
		Repaint();
	}

	void OnGUI()
	{
		GUILayout.BeginHorizontal(EditorStyles.toolbar);

			GUILayout.FlexibleSpace();

			GUI.backgroundColor = collapse ? disabledColor : Color.white;
			if(GUILayout.Button("Collapse", EditorStyles.toolbarButton))
				collapse = !collapse;
			GUI.backgroundColor = Color.white;

			if(GUILayout.Button("Clear", EditorStyles.toolbarButton))
				logs.Clear();

		GUILayout.EndHorizontal();

		GUILayout.BeginHorizontal();
			GUILayout.Label("Callback Log", EditorStyles.boldLabel);
		GUILayout.EndHorizontal();

		Rect r = GUILayoutUtility.GetLastRect();
		r.x = 0;
		r.y = r.y + r.height + 6;
		r.width = this.position.width;
		r.height = this.position.height;

		GUILayout.Space(4);

		pb_EditorGUIUtility.DrawSolidColor(r, logBackgroundColor);

		scroll = GUILayout.BeginScrollView(scroll);

		int len = logs.Count;
		int min = System.Math.Max(0, len - 1024);

		for(int i = len - 1; i >= min; i--)
		{
			if(	collapse &&
				i > 0 &&
				i < len - 1 &&
				logs[i].Equals(logs[i-1]) &&
				logs[i].Equals(logs[i+1]) )
				continue;

			GUILayout.Label(string.Format("{0,3}: {1}", i, logs[i]));
		}

		GUILayout.EndScrollView();
	}
}