using Docker.DotNet;
using Docker.DotNet.Models;
using MoonCore.Attributes;
using MoonlightServers.Daemon.Configuration;

namespace MoonlightServers.Daemon.Services;

[Singleton]
public class DockerImageService
{
    private readonly DockerClient DockerClient;
    private readonly AppConfiguration Configuration;
    private readonly ILogger<DockerImageService> Logger;

    public DockerImageService(
        DockerClient dockerClient,
        ILogger<DockerImageService> logger,
        AppConfiguration configuration
    )
    {
        Configuration = configuration;
        DockerClient = dockerClient;
        Logger = logger;
    }

    public async Task Ensure(string name, Action<string>? onProgressUpdated)
    {
        // Figure out if and which credentials to use by checking for the domain
        AuthConfig credentials = new();

        var domain = GetDomainFromDockerImageName(name);

        var configuredCredentials = Configuration.Docker.Credentials
            .FirstOrDefault(x => x.Domain.Equals(domain, StringComparison.InvariantCultureIgnoreCase));

        if (configuredCredentials != null)
        {
            credentials.Username = configuredCredentials.Username;
            credentials.Password = configuredCredentials.Password;
            credentials.Email = configuredCredentials.Email;
        }
        
        // Now we want to pull the image
        await DockerClient.Images.CreateImageAsync(new()
            {
                FromImage = name
            },
            credentials,
            new Progress<JSONMessage>(async message =>
            {
                if (message.Progress == null)
                    return;

                var line = $"[{message.ID}] {message.ProgressMessage}";

                Logger.LogInformation("{line}", line);

                if (onProgressUpdated != null)
                    onProgressUpdated.Invoke(line);
            })
        );
    }

    private string GetDomainFromDockerImageName(string name) // Method names are my passion ;)
    {
        var nameParts = name.Split("/");
        
        // If it has 1 part -> just the image name (e.g., "ubuntu")
        // If it has 2 parts -> usually "user/image" (e.g., "library/ubuntu")
        // If it has 3 or more -> assume first part is the registry domain

        if (nameParts.Length >= 3 || (nameParts.Length >= 2 && nameParts[0].Contains('.') || nameParts[0].Contains(':')))
            return nameParts[0]; // Registry domain is explicitly specified
        
        return "docker.io"; // Default Docker registry
    }
}