/************************************************************************************

Copyright   :   Copyright (c) Facebook Technologies, LLC and its affiliates. All rights reserved.

Licensed under the Oculus SDK License Version 3.4.1 (the "License");
you may not use the Oculus SDK except in compliance with the License,
which is provided at the time of installation or download, or which
otherwise accompanies this software in either electronic or hard copy form.

You may obtain a copy of the License at

https://developer.oculus.com/licenses/sdk-3.4.1

Unless required by applicable law or agreed to in writing, the Oculus SDK
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

************************************************************************************/

using UnityEngine;
using UnityEditor;
using System.IO;

/// <summary>
/// From the selected transform, takes a cubemap screenshot that can be submitted with the application
/// as a screenshot (or additionally used for reflection shaders).
/// </summary>
class OVRScreenshotWizard : ScriptableWizard
{
	public enum TexFormat
	{
		JPEG,	// 512kb at 1k x 1k resolution vs
		PNG,	// 5.3mb
	}

	public enum SaveMode {
		SaveCubemapScreenshot,
		SaveUnityCubemap,
		SaveBoth,
	}

	public GameObject		renderFrom = null;
	public int				size = 2048;
	public SaveMode			saveMode = SaveMode.SaveUnityCubemap;
	public string			cubeMapFolder = "Assets/Textures/Cubemaps";
	public TexFormat		textureFormat = TexFormat.PNG;

	/// <summary>
	/// Validates the user's input
	/// </summary>
	void OnWizardUpdate()
	{
		helpString = "Select a game object positioned in the place where\nyou want to render the cubemap screenshot from: ";
		isValid = (renderFrom != null);
	}

	/// <summary>
	/// Create the asset path if it is not available.
	/// Assuming the newFolderPath is stated with "Assets", which is a requirement.
	/// </summary>
 	static bool CreateAssetPath( string newFolderPath )
	{
		const  int maxFoldersCount = 32;
		string currentPath;
		string[] pathFolders;

		pathFolders = newFolderPath.Split (new char[]{ '/' }, maxFoldersCount);

		if (!string.Equals ("Assets", pathFolders [0], System.StringComparison.OrdinalIgnoreCase))
		{
			Debug.LogError( "Folder path has to be started with \" Assets \" " );
			return false;
		}

		currentPath = "Assets";
		for (int i = 1; i < pathFolders.Length; i++)
		{
			if (!string.IsNullOrEmpty(pathFolders[i]))
			{
				string newPath = currentPath + "/" + pathFolders[i];
				if (!AssetDatabase.IsValidFolder(newPath))
					AssetDatabase.CreateFolder(currentPath, pathFolders[i]);
				currentPath = newPath;
			}
		}

		Debug.Log( "Created path: " + currentPath );
		return true;
	}

	/// <summary>
	/// Renders the cubemap
	/// </summary>
	void OnWizardCreate()
	{
		if ( !AssetDatabase.IsValidFolder( cubeMapFolder ) )
		{
			if (!CreateAssetPath(cubeMapFolder))
			{
				Debug.LogError( "Created path failed: " + cubeMapFolder );
				return;
			}
		}

		bool existingCamera = true;
		bool existingCameraStateSave = true;
		Camera camera = renderFrom.GetComponent<Camera>();
		if (camera == null)
		{
			camera = renderFrom.AddComponent<Camera>();
			camera.farClipPlane = 10000f;
			existingCamera = false;
		}
		else
		{
			existingCameraStateSave = camera.enabled;
			camera.enabled = true;
		}
		// find the last screenshot saved
		if (cubeMapFolder[cubeMapFolder.Length-1] != '/')
		{
			cubeMapFolder += "/";
		}
		int idx = 0;
		string[] fileNames = Directory.GetFiles(cubeMapFolder);
		foreach(string fileName in fileNames)
		{
			if (!fileName.ToLower().EndsWith(".cubemap"))
			{
				continue;
			}
			string temp = fileName.Replace(cubeMapFolder + "vr_screenshot_", string.Empty);
			temp = temp.Replace(".cubemap", string.Empty);
			int tempIdx = 0;
			if (int.TryParse( temp, out tempIdx ))
			{
				if (tempIdx > idx)
				{
					idx = tempIdx;
				}
			}
		}
		string pathName = string.Format("{0}vr_screenshot_{1}.cubemap", cubeMapFolder, (++idx).ToString("d2"));
		Cubemap cubemap = new Cubemap(size, TextureFormat.RGB24, false);

		// render into cubemap
		if ((camera != null) && (cubemap != null))
		{
			// set up cubemap defaults
			OVRCubemapCapture.RenderIntoCubemap(camera, cubemap);
			if (existingCamera)
			{
				camera.enabled = existingCameraStateSave;
			}
			else
			{
				DestroyImmediate(camera);
			}
			// generate a regular texture as well?
			if ( ( saveMode == SaveMode.SaveCubemapScreenshot ) || ( saveMode == SaveMode.SaveBoth ) )
			{
				GenerateTexture(cubemap, pathName);
			}

			if ( ( saveMode == SaveMode.SaveUnityCubemap ) || ( saveMode == SaveMode.SaveBoth ) )
			{
				Debug.Log( "Saving: " + pathName );
				// by default the unity cubemap isn't saved
				AssetDatabase.CreateAsset( cubemap, pathName );
				// reimport as necessary
				AssetDatabase.SaveAssets();
				// select it in the project tree so developers can find it
				EditorGUIUtility.PingObject( cubemap );
				Selection.activeObject = cubemap;
			}
			AssetDatabase.Refresh();
		}
	}

	/// <summary>
	/// Generates a NPOT 6x1 cubemap in the following format PX NX PY NY PZ NZ
	/// </summary>
	void GenerateTexture(Cubemap cubemap, string pathName)
	{
		// Encode the texture and save it to disk
		pathName = pathName.Replace(".cubemap", (textureFormat == TexFormat.PNG) ? ".png" : ".jpg" ).ToLower();
		pathName = pathName.Replace( cubeMapFolder.ToLower(), "" );
		string format = textureFormat.ToString();
		string fullPath = EditorUtility.SaveFilePanel( string.Format( "Save Cubemap Screenshot as {0}", format ), "", pathName, format.ToLower() );
		if ( !string.IsNullOrEmpty( fullPath ) )
		{
			Debug.Log( "Saving: " + fullPath );
			OVRCubemapCapture.SaveCubemapCapture(cubemap, fullPath);
		}
	}

	/// <summary>
	/// Unity Editor menu option to take a screenshot
	/// </summary>
	[MenuItem("Oculus/Tools/OVR Screenshot Wizard", false, 100000)]
	static void TakeOVRScreenshot()
	{
		OVRScreenshotWizard wizard = ScriptableWizard.DisplayWizard<OVRScreenshotWizard>("OVR Screenshot Wizard", "Render Cubemap");
		if (wizard != null)
		{
			if (Selection.activeGameObject != null)
			wizard.renderFrom = Selection.activeGameObject;
			else
			wizard.renderFrom = Camera.main.gameObject;

			wizard.isValid = (wizard.renderFrom != null);
		}
	}
}