Editor extention script to download and import "HoloToolkit-Unity"

HoloToolkitImporter.cs

/*
	Copyright (c) 2016 Keizo Nagamine
	Released under the MIT license
	http://opensource.org/licenses/mit-license.php
*/

/*
 * @Usage
 * 1. Import this script into "Editor" directory.
 * 2. Select "Assets/Import HoloToolkit" menu item.
 * 
 * @Require
 * Windows10 (or PowerShell v5 installed PC)
 */

using System.IO;
using UnityEngine;
using UnityEditor;

/// <summary>
/// Download and import "HoloToolkit-Unity"
/// </summary>
public static class HoloToolkitImporter
{
    private static WWW www;
    private static System.Diagnostics.Process process;

    private const string dowoloadUrl = "https://github.com/Microsoft/HoloToolkit-Unity/archive/master.zip";

    private static string tempPath { get { return CombinePath(Application.dataPath, "..", "Temp", "HoloToolkitImporter"); } }
    private static string zipFilePath { get { return CombinePath(tempPath, "HoloToolkit-Unity.zip"); } }
    private static string zipExpandPath { get { return CombinePath(tempPath, "HoloToolkit-Unity"); } }
    private static string projectPath { get { return CombinePath(zipExpandPath, "HoloToolkit-Unity-master"); } }
    private static string exportPackagePath { get { return CombinePath(tempPath, "HoloToolkit-Unity.unitypackage"); } }

    [MenuItem("Assets/Import HoloToolkit")]
    public static void Execute()
    {
        Directory.CreateDirectory(tempPath);

        Download();
    }

    #region Download

    // Download "Holotoolkit-Unity" zip file from github.
    private static void Download()
    {
        www = new WWW(dowoloadUrl);

        EditorApplication.update += DownloadUpdate;
    }

    private static void DownloadUpdate()
    {
        EditorUtility.DisplayProgressBar("Hold on", "Downloading HoloToolkit", www.progress);

        if (!string.IsNullOrEmpty(www.error))
        {
            Debug.LogError(www.error);
            FinishDownload();
        }
        else if(www.isDone)
        {
            // Save as  zip file.
            File.WriteAllBytes(zipFilePath, www.bytes);
            FinishDownload();
            Unzip();
        }
    }

    private static void FinishDownload()
    {
        www.Dispose();
        www = null;
        EditorUtility.ClearProgressBar();
        EditorApplication.update -= DownloadUpdate;
    }

    #endregion

    #region Unzip

    // Unzip by using windows powershell
    private static void Unzip()
    {
        if(!File.Exists(zipFilePath))
        {
            Debug.LogErrorFormat("{0} is not exist.", zipFilePath);
            return;
        }

        process = new System.Diagnostics.Process();

        // Get path to command prompt 
        process.StartInfo.FileName = System.Environment.GetEnvironmentVariable("ComSpec");

        process.StartInfo.CreateNoWindow = true;
        process.StartInfo.UseShellExecute = false;

        // Set unzip command as arguments
        process.StartInfo.Arguments = string.Format("/c powershell expand-archive \"{0}\" \"{1}\" -force", zipFilePath, zipExpandPath);

        process.Start();

        EditorApplication.update += UnzipUpdate;
        EditorUtility.DisplayProgressBar("Hold on", "Unzip HoloToolkit", 1);
    }

    private static void UnzipUpdate()
    {
        if(process.HasExited)
        {
            process.Close();
            process = null;
            EditorUtility.ClearProgressBar();
            EditorApplication.update -= UnzipUpdate;

            Export();
        }
    }

    #endregion

    #region Export

    // Export UnityPackage from unzipped directory 
    private static void Export()
    {
        if (!Directory.Exists(projectPath))
        {
            Debug.LogErrorFormat("{0} is not exist.", projectPath);
            return;
        }

        process = new System.Diagnostics.Process();

        process.StartInfo.FileName = EditorApplication.applicationPath;
        process.StartInfo.Arguments = string.Format("-batchmode -quit -projectPath \"{1}\" -exportPackage Assets \"{2}\"", EditorApplication.applicationPath, projectPath, exportPackagePath);
        process.Start();

        EditorApplication.update += ExportUpdate;
        EditorUtility.DisplayProgressBar("Hold on", "Export HoloToolkit", 1);
    }

    private static void ExportUpdate()
    {
        if (process.HasExited)
        {
            process.Close();
            process = null;
            EditorUtility.ClearProgressBar();
            EditorApplication.update -= ExportUpdate;

            Import();
        }
    }

    #endregion

    #region Import

    // Import UnityPackage
    private static void Import()
    {
        if (!File.Exists(exportPackagePath))
        {
            Debug.LogErrorFormat("{0} is not exist.", exportPackagePath);
            return;
        }

        AssetDatabase.ImportPackage(exportPackagePath, false);
    }

    #endregion

    #region Utility

    private static string CombinePath(params string[] paths)
    {
        if (paths == null) { return null; }

        string combinedPath = "";

        foreach (var path in paths)
        {
            if (path != null)
            {
                combinedPath = Path.Combine(combinedPath, path);
            }
        }

        return combinedPath;
    }

    #endregion
}