SteamVR_Update.cs

//======= Copyright (c) Valve Corporation, All rights reserved. ===============
//
// Purpose: Notify developers when a new version of the plugin is available.
//
//=============================================================================

using UnityEngine;
using UnityEditor;
using System.IO;
using System.Text.RegularExpressions;

[InitializeOnLoad]
public class SteamVR_Update : EditorWindow
{
    const string currentVersion = "1.2.3";
    const string versionUrl = "http://media.steampowered.com/apps/steamvr/unitypluginversion.txt";
    const string notesUrl = "http://media.steampowered.com/apps/steamvr/unityplugin-v{0}.txt";
    const string pluginUrl = "http://u3d.as/content/valve-corporation/steam-vr-plugin";
    const string doNotShowKey = "SteamVR.DoNotShow.v{0}";

    static bool gotVersion = false;
    static WWW wwwVersion, wwwNotes;
    static string version, notes;
    static SteamVR_Update window;

    static SteamVR_Update()
    {
        EditorApplication.update += Update;
    }

    static void Update()
    {
        if (!gotVersion)
        {
            if (wwwVersion == null)
                wwwVersion = new WWW(versionUrl);

            if (!wwwVersion.isDone)
                return;

            if (UrlSuccess(wwwVersion))
                version = wwwVersion.text;

            wwwVersion = null;
            gotVersion = true;

            if (ShouldDisplay())
            {
                var url = string.Format(notesUrl, version);
                wwwNotes = new WWW(url);

                window = GetWindow<SteamVR_Update>(true);
                window.minSize = new Vector2(320, 440);
                //window.title = "SteamVR";
            }
        }

        if (wwwNotes != null)
        {
            if (!wwwNotes.isDone)
                return;

            if (UrlSuccess(wwwNotes))
                notes = wwwNotes.text;

            wwwNotes = null;

            if (notes != "")
                window.Repaint();
        }

        EditorApplication.update -= Update;
    }

    static bool UrlSuccess(WWW www)
    {
        if (!string.IsNullOrEmpty(www.error))
            return false;
        if (Regex.IsMatch(www.text, "404 not found", RegexOptions.IgnoreCase))
            return false;
        return true;
    }

    static bool ShouldDisplay()
    {
        if (string.IsNullOrEmpty(version))
            return false;
        if (version == currentVersion)
            return false;
        if (EditorPrefs.HasKey(string.Format(doNotShowKey, version)))
            return false;

        // parse to see if newer (e.g. 1.0.4 vs 1.0.3)
        var versionSplit = version.Split('.');
        var currentVersionSplit = currentVersion.Split('.');
        for (int i = 0; i < versionSplit.Length && i < currentVersionSplit.Length; i++)
        {
            int versionValue, currentVersionValue;
            if (int.TryParse(versionSplit[i], out versionValue) &&
                int.TryParse(currentVersionSplit[i], out currentVersionValue))
            {
                if (versionValue > currentVersionValue)
                    return true;
                if (versionValue < currentVersionValue)
                    return false;
            }
        }

        // same up to this point, now differentiate based on number of sub values (e.g. 1.0.4.1 vs 1.0.4)
        if (versionSplit.Length <= currentVersionSplit.Length)
            return false;

        return true;
    }

    Vector2 scrollPosition;
    bool toggleState;

    string GetResourcePath()
    {
        var ms = MonoScript.FromScriptableObject(this);
        var path = AssetDatabase.GetAssetPath(ms);
        path = Path.GetDirectoryName(path);
        return path.Substring(0, path.Length - "Editor".Length) + "Textures/";
    }

    public void OnGUI()
    {
        EditorGUILayout.HelpBox("A new version of the SteamVR plugin is available!", MessageType.Warning);

        var resourcePath = GetResourcePath();
        var logo = AssetDatabase.LoadAssetAtPath<Texture2D>(resourcePath + "logo.png");
        var rect = GUILayoutUtility.GetRect(position.width, 150, GUI.skin.box);
        if (logo)
            GUI.DrawTexture(rect, logo, ScaleMode.ScaleToFit);

        scrollPosition = GUILayout.BeginScrollView(scrollPosition);

        GUILayout.Label("Current version: " + currentVersion);
        GUILayout.Label("New version: " + version);

        if (notes != "")
        {
            GUILayout.Label("Release notes:");
            EditorGUILayout.HelpBox(notes, MessageType.Info);
        }

        GUILayout.EndScrollView();

        GUILayout.FlexibleSpace();

        if (GUILayout.Button("Get Latest Version"))
        {
            Application.OpenURL(pluginUrl);
        }

        EditorGUI.BeginChangeCheck();
        var doNotShow = GUILayout.Toggle(toggleState, "Do not prompt for this version again.");
        if (EditorGUI.EndChangeCheck())
        {
            toggleState = doNotShow;
            var key = string.Format(doNotShowKey, version);
            if (doNotShow)
                EditorPrefs.SetBool(key, true);
            else
                EditorPrefs.DeleteKey(key);
        }
    }
}