/BlogEngine/BlogEngine.NET/App_Code/Extensions/SyntaxHighlighter.cs

using System.Text;

using System.Web;

using System.Web.UI.HtmlControls;

using BlogEngine.Core;

using BlogEngine.Core.Web.Controls;

using BlogEngine.Core.Web.Extensions;

using Page=System.Web.UI.Page;

using System.Collections.Generic;

using System;



[Extension("Adds <a target=\"_new\" href=\"http://alexgorbatchev.com/wiki/SyntaxHighlighter\">Alex Gorbatchev's</a> source code formatter", "2.5.1", "<a target=\"_new\" href=\"http://dotnetblogengine.net/\">BlogEngine.NET</a>")]

public class SyntaxHighlighter

{

    #region Private members

    private const string ExtensionName = "SyntaxHighlighter";

    static protected Dictionary<Guid, ExtensionSettings> _blogsOptions = new Dictionary<Guid, ExtensionSettings>();

    static protected Dictionary<Guid, ExtensionSettings> _blogsThemes = new Dictionary<Guid, ExtensionSettings>();

    #endregion



    /// <summary>

    ///     The sync root.

    /// </summary>

    private static readonly object syncRoot = new object();



    private static ExtensionSettings Options

    {

        get

        {

            Guid blogId = Blog.CurrentInstance.Id;

            ExtensionSettings options = null;

            _blogsOptions.TryGetValue(blogId, out options);



            if (options == null)

            {

                lock (syncRoot)

                {

                    _blogsOptions.TryGetValue(blogId, out options);



                    if (options == null)

                    {

                        // Initializes

                        //   (1) Options

                        //   (3) Themees

                        // for the current blog instance.



                        // options

                        options = new ExtensionSettings("Options");

                        options.IsScalar = true;

                        options.Help = OptionsHelp();



                        options.AddParameter("cdnScriptsPath", "CDN Script Path", 250, false);

                        options.AddParameter("cdnStylesPath", "CDN Styles Path", 250, false);

                        options.AddParameter("gutter", "Gutter");

                        options.AddParameter("smart-tabs", "Smart tabs");

                        options.AddParameter("auto-links", "Auto links");

                        options.AddParameter("collapse", "Collapse");

                        options.AddParameter("tab-size", "Tab size");

                        options.AddParameter("toolbar", "Toolbar");



                        options.AddValue("cdnScriptsPath", "http://alexgorbatchev.com.s3.amazonaws.com/pub/sh/3.0.83/scripts/");

                        options.AddValue("cdnStylesPath", "http://alexgorbatchev.com.s3.amazonaws.com/pub/sh/3.0.83/styles/");

                        options.AddValue("gutter", true);

                        options.AddValue("smart-tabs", true);

                        options.AddValue("auto-links", true);

                        options.AddValue("collapse", false);

                        options.AddValue("tab-size", 4);

                        options.AddValue("toolbar", true);



                        _blogsOptions[blogId] = ExtensionManager.InitSettings(ExtensionName, options);



                        // themes

                        ExtensionSettings themes = new ExtensionSettings("Themes");

                        themes.IsScalar = true;

                        themes.AddParameter("SelectedTheme", "Themes", 20, false, false, ParameterType.ListBox);

                        themes.AddValue("SelectedTheme", new string[] { "Default", "Django", "Eclipse", "Emacs", "FadeToGrey", "MDUltra", "Midnight", "Dark" }, "Default");

                        _blogsThemes[blogId] = ExtensionManager.InitSettings(ExtensionName, themes);

                    }

                }

            }



            return options;

        }

    }



    private static ExtensionSettings Themes

    {

        get

        {

            // by invoking the "Options" property getter, we are ensuring

            // that an entry is put into _blogsThemes for the current blog instance.

            ExtensionSettings options = Options;

            return _blogsThemes[Blog.CurrentInstance.Id];

        }

    }



    static SyntaxHighlighter()

    {

        Post.Serving += AddSyntaxHighlighter;

        InitSettings();

    }



    private static void AddSyntaxHighlighter(object sender, ServingEventArgs e)

    {

        if (!ExtensionManager.ExtensionEnabled("SyntaxHighlighter"))

            return;



		if(e.Location == ServingLocation.Feed) 

            return;



        // if no code blocks on the page - don't bother

        if (!e.Body.ToLowerInvariant().Contains("<pre class=\"brush:"))

            return;

	

        HttpContext context = HttpContext.Current;

		

        Page page = (Page)context.CurrentHandler;



        if ((context.CurrentHandler is Page == false) || (context.Items[ExtensionName] != null))

        {

            return;

        }



        AddCssStyles(page);

        AddJavaScripts(page);

        AddOptions(page);



        context.Items[ExtensionName] = 1;

    }



    private static void AddCssStyles(Page page)

    {

        AddStylesheet("shCore.css", page);



        if (Themes != null)

        {

            switch (Themes.GetSingleValue("SelectedTheme"))

            {

                case "Django":

                    AddStylesheet("shThemeDjango.css", page);

                    break;

                case "Eclipse":

                    AddStylesheet("shThemeEclipse.css", page);

                    break;

                case "Emacs":

                    AddStylesheet("shThemeEmacs.css", page);

                    break;

                case "FadeToGrey":

                    AddStylesheet("shThemeFadeToGrey.css", page);

                    break;

                case "MDUltra":

                    AddStylesheet("shThemeMDUltra.css", page);

                    break;

                case "Midnight":

                    AddStylesheet("shThemeMidnight.css", page);

                    break;

                case "Dark":

                    AddStylesheet("shThemeRDark.css", page);

                    break;

                default:

                    AddStylesheet("shThemeDefault.css", page);

                    break;

            }

        }       

    }



    private static void AddJavaScripts(Page page)

    {

        AddJavaScript("shCore.js", page);

        AddJavaScript("shAutoloader.js", page);



        // register starter script

        page.ClientScript.RegisterStartupScript(page.GetType(), "shInit.js", 

            String.Format("<script type=\"text/javascript\" src=\"{0}\"></script>", GetUrl("Scripts/syntaxhighlighter/", "shInit.js")));

    }



    #region Script/Style adding



    private static void AddJavaScript(string src, Page page)

    {

        page.ClientScript.RegisterStartupScript(page.GetType(), src, String.Format("<script type=\"text/javascript\" src=\"{0}\"></script>", GetUrl(ScriptsFolder(), src)));

    }



    private static void AddStylesheet(string href, Page page)

    {

        HtmlLink css = new HtmlLink();

        css.Attributes["type"] = "text/css";

        css.Attributes["rel"] = "stylesheet";

        css.Attributes["href"] = GetUrl(StylesFolder(), href);

        page.Header.Controls.Add(css);

    }



    private static void AddOptions(Page page)

    {

        StringBuilder sb = new StringBuilder();

        

        sb.AppendLine("<script type=\"text/javascript\" defer=\"defer\">");



        // add not-default options

        if (Options != null)

        {

            if(Options.GetSingleValue("gutter").ToLowerInvariant() == "false")

                sb.AppendLine(GetOption("gutter"));



            if (Options.GetSingleValue("smart-tabs").ToLowerInvariant() == "false")

                sb.AppendLine(GetOption("smart-tabs"));



            if (Options.GetSingleValue("auto-links").ToLowerInvariant() == "false")

                sb.AppendLine(GetOption("auto-links"));



            if (Options.GetSingleValue("collapse").ToLowerInvariant() == "true")

                sb.AppendLine(GetOption("collapse"));

            

            if (Options.GetSingleValue("toolbar").ToLowerInvariant() == "false")

                sb.AppendLine(GetOption("toolbar"));



            if (Options.GetSingleValue("tab-size") != "4")

                sb.AppendLine(GetOption("tab-size"));



            // depricated in latest version

            //sb.AppendLine(GetOption("light"));

            //sb.AppendLine(GetOption("wrap-lines"));

        }  

        

        sb.AppendLine("\tSyntaxHighlighter.all();");

        sb.AppendLine("</script>");

        page.ClientScript.RegisterStartupScript(page.GetType(), "SyntaxHighlighter", sb.ToString(), false);

    }



    private static string GetUrl(string folder, string url)

    {

        string s = HttpContext.Current.Server.UrlPathEncode(string.Format("{0}{1}", folder, url));

        if (!folder.ToLowerInvariant().Contains("http:") && !folder.ToLowerInvariant().Contains("https://"))

            s = Utils.ApplicationRelativeWebRoot + s;

        return s;

    }

    

    #endregion



    #region Private methods



    private static void InitSettings()

    {

        // call Options getter so default settings are loaded on application start.

        var s = Options;

    }



    static string OptionsHelp()

    {

        StringBuilder sb = new StringBuilder();

        sb.AppendLine("<p>This extension implements excellent Alex Gorbatchev's syntax highlighter JS library for source code formatting. Please refer to <a target=\"_new\" href=\"http://alexgorbatchev.com/wiki/SyntaxHighlighter:Usage\">this site</a> for usage.</p>");

        sb.AppendLine("<p><b>cdnScriptsPath</b>: Allows you to load the SyntaxHighlighter script from a CDN. Leave empty for local files</p>");

        sb.AppendLine("<p><b>cdnStylesPath</b>: Allows you to load the SyntaxHighlighter styles from a CDN. Leave empty for local files</p>");

        sb.AppendLine("<p><b>auto-links</b>: Allows you to turn detection of links in the highlighted element on and off. If the option is turned off, URLs won't be clickable.</p>");

        sb.AppendLine("<p><b>collapse</b>: Allows you to force highlighted elements on the page to be collapsed by default.</p>");

        sb.AppendLine("<p><b>gutter</b>:	Allows you to turn gutter with line numbers on and off.</p>");

        sb.AppendLine("<p><b>smart-tabs</b>:	Allows you to turn smart tabs feature on and off.</p>");

        sb.AppendLine("<p><b>tab-size</b>: Allows you to adjust tab size.</p>");

        sb.AppendLine("<p><b>toolbar</b>: Toggles toolbar on/off.</p>");

        sb.AppendLine("<p><a target=\"_new\" href=\"http://alexgorbatchev.com/wiki/SyntaxHighlighter:Configuration\">more...</a></p>");

        return sb.ToString();

    }



    static string GetOption(string opt)

    {

        if (Options != null)

        {

            string pattern = "\tSyntaxHighlighter.defaults['{0}'] = {1};";

            string val = Options.GetSingleValue(opt).ToLowerInvariant();

            return string.Format(pattern, opt, val);

        }

        return "";

    }



    static string ScriptsFolder()

    {

        if (Options != null)

        {

            if (!String.IsNullOrEmpty(Options.GetSingleValue("cdnScriptsPath")))

                return Options.GetSingleValue("cdnScriptsPath");

            else

                return "Scripts/syntaxhighlighter/";

        }

        return "";

    }



    static string StylesFolder()

    {

        if (Options != null)

        {

            if (!String.IsNullOrEmpty(Options.GetSingleValue("cdnStylesPath")))

                return Options.GetSingleValue("cdnStylesPath");

            else

                return "Styles/syntaxhighlighter/";

        }

        return "";

    }



    #endregion

}