using OTSSignsOrchestrator.Server.Clients;
using OTSSignsOrchestrator.Server.Data.Entities;

namespace OTSSignsOrchestrator.Server.Health.Checks;

/// <summary>
/// Verifies the OAuth2 app in <see cref="OauthAppRegistry"/> can still authenticate
/// by testing a <c>client_credentials</c> flow against the Xibo CMS instance.
/// AutoRemediate=false — credential rotation requires a separate job.
/// </summary>
public sealed class OauthAppHealthCheck : IHealthCheck
{
    private readonly XiboClientFactory _clientFactory;
    private readonly IServiceProvider _services;
    private readonly ILogger<OauthAppHealthCheck> _logger;

    public string CheckName => "OauthApp";
    public bool AutoRemediate => false;

    public OauthAppHealthCheck(
        XiboClientFactory clientFactory,
        IServiceProvider services,
        ILogger<OauthAppHealthCheck> logger)
    {
        _clientFactory = clientFactory;
        _services = services;
        _logger = logger;
    }

    public async Task<HealthCheckResult> RunAsync(Instance instance, CancellationToken ct)
    {
        var oauthApp = instance.OauthAppRegistries.FirstOrDefault();
        if (oauthApp is null)
            return new HealthCheckResult(HealthStatus.Critical, "No OAuth app registered");

        var abbrev = instance.Customer.Abbreviation;
        var settings = _services.GetRequiredService<Core.Services.SettingsService>();
        var secret = await settings.GetAsync(Core.Services.SettingsService.InstanceOAuthSecretId(abbrev));

        if (string.IsNullOrEmpty(secret))
            return new HealthCheckResult(HealthStatus.Critical,
                "OAuth client secret not found in Bitwarden — cannot authenticate");

        try
        {
            // Attempt to create a client (which fetches a token via client_credentials)
            var client = await _clientFactory.CreateAsync(instance.XiboUrl, oauthApp.ClientId, secret);

            // If we got here, the token was obtained successfully
            return new HealthCheckResult(HealthStatus.Healthy, "OAuth2 client_credentials flow successful");
        }
        catch (Exception ex)
        {
            return new HealthCheckResult(HealthStatus.Critical,
                $"OAuth2 authentication failed: {ex.Message}",
                "Credential rotation job may be required");
        }
    }
}