DocSpace-client/common/ASC.Common/Utils/VelocityFormatter.cs

/*
 *
 * (c) Copyright Ascensio System Limited 2010-2018
 *
 * This program is freeware. You can redistribute it and/or modify it under the terms of the GNU 
 * General Public License (GPL) version 3 as published by the Free Software Foundation (https://www.gnu.org/copyleft/gpl.html). 
 * In accordance with Section 7(a) of the GNU GPL its Section 15 shall be amended to the effect that 
 * Ascensio System SIA expressly excludes the warranty of non-infringement of any third-party rights.
 *
 * THIS PROGRAM IS DISTRIBUTED WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. For more details, see GNU GPL at https://www.gnu.org/copyleft/gpl.html
 *
 * You can contact Ascensio System SIA by email at sales@onlyoffice.com
 *
 * The interactive user interfaces in modified source and object code versions of ONLYOFFICE must display 
 * Appropriate Legal Notices, as required under Section 5 of the GNU GPL version 3.
 *
 * Pursuant to Section 7 § 3(b) of the GNU GPL you must retain the original ONLYOFFICE logo which contains 
 * relevant author attributions when distributing the software. If the display of the logo in its graphic 
 * form is not reasonably feasible for technical reasons, you must include the words "Powered by ONLYOFFICE" 
 * in every copy of the program you distribute. 
 * Pursuant to Section 7 § 3(e) we decline to grant you any rights under trademark law for use of our trademarks.
 *
*/

namespace ASC.Common.Utils;

public class TextLoader : ResourceLoader
{
    public override void Init(Commons.Collections.ExtendedProperties configuration)
    {
        //nothing to configure
    }

    public override Stream GetResourceStream(string source)
    {
        return new MemoryStream(Encoding.UTF8.GetBytes(source));
    }

    public override long GetLastModified(NVelocity.Runtime.Resource.Resource resource)
    {
        return 1;
    }

    public override bool IsSourceModified(NVelocity.Runtime.Resource.Resource resource)
    {
        return false;
    }
}

public static class VelocityFormatter
{
    private static bool _initialized;
    private static readonly ConcurrentDictionary<string, Template> _patterns = new ConcurrentDictionary<string, Template>();

    public static string FormatText(string templateText, IDictionary<string, object> values)
    {
        var nvelocityContext = new VelocityContext();

        foreach (var tagValue in values)
        {
            nvelocityContext.Put(tagValue.Key, tagValue.Value);
        }

        return FormatText(templateText, nvelocityContext);
    }

    public static string FormatText(string templateText, VelocityContext context)
    {
        if (!_initialized)
        {
            var properties = new Commons.Collections.ExtendedProperties();
            properties.AddProperty("resource.loader", "custom");
            properties.AddProperty("custom.resource.loader.class", "ASC.Common.Utils.TextLoader; ASC.Common");
            properties.AddProperty("input.encoding", Encoding.UTF8.WebName);
            properties.AddProperty("output.encoding", Encoding.UTF8.WebName);
            Velocity.Init(properties);
            _initialized = true;
        }

        using var writer = new StringWriter();
        var key = templateText.GetHashCode().ToString();

        if (!_patterns.TryGetValue(key, out var template))
        {
            template = Velocity.GetTemplate(templateText);
            _patterns.TryAdd(key, template);
        }

        template.Merge(context, writer);

        return writer.GetStringBuilder().ToString();
    }
}