Umbraco-CMS/src/Umbraco.Core/Routing/DefaultMediaUrlProvider.cs

using Umbraco.Cms.Core.Models.PublishedContent;
using Umbraco.Cms.Core.PropertyEditors;

namespace Umbraco.Cms.Core.Routing;

/// <summary>
///     Default media URL provider.
/// </summary>
public class DefaultMediaUrlProvider : IMediaUrlProvider
{
    private readonly MediaUrlGeneratorCollection _mediaPathGenerators;
    private readonly UriUtility _uriUtility;

    public DefaultMediaUrlProvider(MediaUrlGeneratorCollection mediaPathGenerators, UriUtility uriUtility)
    {
        _mediaPathGenerators = mediaPathGenerators ?? throw new ArgumentNullException(nameof(mediaPathGenerators));
        _uriUtility = uriUtility;
    }

    /// <inheritdoc />
    public virtual UrlInfo? GetMediaUrl(
        IPublishedContent content,
        string propertyAlias,
        UrlMode mode,
        string? culture,
        Uri current)
    {
        IPublishedProperty? prop = content.GetProperty(propertyAlias);

        // get the raw source value since this is what is used by IDataEditorWithMediaPath for processing
        var value = prop?.GetSourceValue(culture);
        if (value == null)
        {
            return null;
        }

        IPublishedPropertyType? propType = prop?.PropertyType;

        if (_mediaPathGenerators.TryGetMediaPath(propType?.EditorAlias, value, out var path))
        {
            Uri url = AssembleUrl(path!, current, mode);
            return UrlInfo.Url(url.ToString(), culture);
        }

        return null;
    }

    private Uri AssembleUrl(string path, Uri current, UrlMode mode)
    {
        if (string.IsNullOrWhiteSpace(path))
        {
            throw new ArgumentException($"{nameof(path)} cannot be null or whitespace", nameof(path));
        }

        // the stored path is absolute so we just return it as is
        if (Uri.IsWellFormedUriString(path, UriKind.Absolute))
        {
            return new Uri(path);
        }

        Uri uri;

        if (current == null)
        {
            mode = UrlMode.Relative; // best we can do
        }

        switch (mode)
        {
            case UrlMode.Absolute:
                uri = new Uri(current?.GetLeftPart(UriPartial.Authority) + path);
                break;
            case UrlMode.Relative:
            case UrlMode.Auto:
                uri = new Uri(path, UriKind.Relative);
                break;
            default:
                throw new ArgumentOutOfRangeException(nameof(mode));
        }

        return _uriUtility.MediaUriFromUmbraco(uri);
    }
}