ShareX/ShareX.UploadersLib/CustomUploader/Functions/CustomUploaderFunctionRegex.cs

#region License Information (GPL v3)

/*
    ShareX - A program that allows you to take screenshots and share any file type
    Copyright (c) 2007-2023 ShareX Team

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

    Optionally you can also view the license at <http://www.gnu.org/licenses/>.
*/

#endregion License Information (GPL v3)

using System.Text.RegularExpressions;

namespace ShareX.UploadersLib
{
    // Example: {regex:(?<=href=").+(?=")}
    // Example: {regex:href="(.+)"|1}
    // Example: {regex:href="(?<url>.+)"|url}
    // Example: {regex:{response}|href="(.+)"|1}
    internal class CustomUploaderFunctionRegex : CustomUploaderFunction
    {
        public override string Name { get; } = "regex";

        public override int MinParameterCount { get; } = 1;

        public override string Call(ShareXCustomUploaderSyntaxParser parser, string[] parameters)
        {
            string input, pattern, group = "";

            if (parameters.Length > 2)
            {
                // {regex:input|pattern|group}
                input = parameters[0];
                pattern = parameters[1];
                group = parameters[2];
            }
            else
            {
                // {regex:pattern}
                input = parser.ResponseInfo.ResponseText;
                pattern = parameters[0];

                if (parameters.Length > 1)
                {
                    // {regex:pattern|group}
                    group = parameters[1];
                }
            }

            if (!string.IsNullOrEmpty(input) && !string.IsNullOrEmpty(pattern))
            {
                Match match = Regex.Match(input, pattern);

                if (match.Success)
                {
                    if (!string.IsNullOrEmpty(group))
                    {
                        if (int.TryParse(group, out int groupNumber))
                        {
                            return match.Groups[groupNumber].Value;
                        }
                        else
                        {
                            return match.Groups[group].Value;
                        }
                    }

                    return match.Value;
                }
            }

            return null;
        }
    }
}