using Microsoft.Extensions.Logging;

namespace zero.Routing;

public class Links : ILinks
{
  protected IZeroStore Store { get; set; }
  protected ILogger<Links> Logger { get; set; }
  protected IEnumerable<ILinkProvider> Providers { get; set; }

  public Links(IZeroStore store, ILogger<Links> logger, IEnumerable<ILinkProvider> providers)
  {
    Store = store;
    Logger = logger;
    Providers = providers;
  }


  /// <inheritdoc />
  public T GetProvider<T>() where T : class, ILinkProvider
  {
    Type type = typeof(T);
    return Providers.FirstOrDefault(x => x.GetType().IsAssignableFrom(type)) as T;
  }


  /// <inheritdoc />
  public async Task<string> GetUrl(Link link)
  {
    ILinkProvider provider = Providers.LastOrDefault(x => x.CanProcess(link));

    if (provider == null)
    {
      Logger.LogWarning("Could not find provider for link with area {area}", link.Area);
      return null;
    }

    return await provider.Resolve(link);
  }


  /// <inheritdoc />
  public async Task<Dictionary<Link, string>> GetUrls(params Link[] links)
  {
    Dictionary<Link, string> result = new();

    foreach (Link link in links)
    {
      result.Add(link, await GetUrl(link));
    }

    return result;
  }


  /// <inheritdoc />
  public ILinkProvider GetProvider(Link link)
  {
    return Providers.LastOrDefault(x => x.CanProcess(link));
  }
}

public interface ILinks
{
  /// <summary>
  /// Get URL from a link object by finding a provider which can resolve the link
  /// </summary>
  Task<string> GetUrl(Link link);

  /// <summary>
  /// Get URLs from link objects by finding matching providers
  /// </summary>
  Task<Dictionary<Link, string>> GetUrls(params Link[] links);

  /// <summary>
  /// Get the provider for a specific link
  /// </summary>
  ILinkProvider GetProvider(Link link);

  /// <summary>
  /// Find a provider by a specific type
  /// </summary>
  T GetProvider<T>() where T : class, ILinkProvider;
}