// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Aspire.Hosting.ApplicationModel;
using Aspire.Hosting.Azure.AppContainers;
using Aspire.Hosting.Lifecycle;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
 
namespace Aspire.Hosting.Azure;
 
/// <summary>
/// Represents the infrastructure for Azure Container Apps within the Aspire Hosting environment.
/// Implements the <see cref="IDistributedApplicationLifecycleHook"/> interface to provide lifecycle hooks for distributed applications.
/// </summary>
internal sealed class AzureContainerAppsInfrastructure(
    ILogger<AzureContainerAppsInfrastructure> logger,
    IOptions<AzureProvisioningOptions> provisioningOptions,
    DistributedApplicationExecutionContext executionContext) : IDistributedApplicationLifecycleHook
{
    public async Task BeforeStartAsync(DistributedApplicationModel appModel, CancellationToken cancellationToken = default)
    {
        if (executionContext.IsRunMode)
        {
            return;
        }
 
        // TODO: We need to support direct association between a compute resource and the container app environment.
        // Right now we support a single container app environment as the one we want to use and we'll fall back to
        // azd based environment if we don't have one.
 
        var caes = appModel.Resources.OfType<AzureContainerAppEnvironmentResource>().ToArray();
 
        if (caes.Length > 1)
        {
            throw new NotSupportedException("Multiple container app environments are not supported.");
        }
 
        var environment = caes.FirstOrDefault() as IAzureContainerAppEnvironment ?? new AzdAzureContainerAppEnvironment();
 
        var containerAppEnvironmentContext = new ContainerAppEnvironmentContext(
            logger,
            environment);
 
        foreach (var r in appModel.Resources)
        {
            if (r.TryGetLastAnnotation<ManifestPublishingCallbackAnnotation>(out var lastAnnotation) && lastAnnotation == ManifestPublishingCallbackAnnotation.Ignore)
            {
                continue;
            }
 
            if (!r.IsContainer() && r is not ProjectResource)
            {
                continue;
            }
 
            var containerApp = await containerAppEnvironmentContext.CreateContainerAppAsync(r, provisioningOptions.Value, executionContext, cancellationToken).ConfigureAwait(false);
 
            // Capture information about the container registry used by the
            // container app environment in the deployment target information
            // associated with each compute resource that needs an image
#pragma warning disable ASPIRECOMPUTE001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
            r.Annotations.Add(new DeploymentTargetAnnotation(containerApp)
            {
                ContainerRegistryInfo = caes.FirstOrDefault(),
                ComputeEnvironment = environment as IComputeEnvironmentResource // will be null if azd
            });
#pragma warning restore ASPIRECOMPUTE001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
        }
 
        static void SetKnownParameterValue(AzureBicepResource r, string key, Func<AzureBicepResource, object> factory)
        {
            if (r.Parameters.TryGetValue(key, out var existingValue) && existingValue is null)
            {
                var value = factory(r);
 
                r.Parameters[key] = value;
            }
        }
 
        if (environment is AzdAzureContainerAppEnvironment)
        {
            // We avoid setting known values if azd is used, it will be resolved by azd at publish time.
            return;
        }
 
        // Resolve the known parameters for the container app environment
        foreach (var r in appModel.Resources.OfType<AzureBicepResource>())
        {
            // HACK: This forces parameters to be resolved for any AzureProvisioningResource
            r.GetBicepTemplateFile();
 
            // This will throw an exception if there's no value specified, in this new mode, we don't no longer support
            // automagic secret key vault references.
            SetKnownParameterValue(r, AzureBicepResource.KnownParameters.KeyVaultName, environment.GetSecretOutputKeyVault);
 
            // Set the known parameters for the container app environment
            SetKnownParameterValue(r, AzureBicepResource.KnownParameters.PrincipalId, _ => environment.PrincipalId);
            SetKnownParameterValue(r, AzureBicepResource.KnownParameters.PrincipalType, _ => "ServicePrincipal");
            SetKnownParameterValue(r, AzureBicepResource.KnownParameters.PrincipalName, _ => environment.PrincipalName);
            SetKnownParameterValue(r, AzureBicepResource.KnownParameters.LogAnalyticsWorkspaceId, _ => environment.LogAnalyticsWorkspaceId);
 
            SetKnownParameterValue(r, "containerAppEnvironmentId", _ => environment.ContainerAppEnvironmentId);
            SetKnownParameterValue(r, "containerAppEnvironmentName", _ => environment.ContainerAppEnvironmentName);
        }
    }
}