// 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;
using Azure.Provisioning;
using Azure.Provisioning.AppConfiguration;
 
namespace Aspire.Hosting;
 
/// <summary>
/// Provides extension methods for adding the Azure AppConfiguration resources to the application model.
/// </summary>
public static class AzureAppConfigurationExtensions
{
    /// <summary>
    /// Adds an Azure App Configuration resource to the application model.
    /// </summary>
    /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/>.</param>
    /// <param name="name">The name of the resource. This name will be used as the connection string name when referenced in a dependency.</param>
    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
    /// <remarks>
    /// By default references to the Azure App Configuration resource will be assigned the following roles:
    /// 
    /// - <see cref="AppConfigurationBuiltInRole.AppConfigurationDataOwner"/>
    ///
    /// These can be replaced by calling <see cref="WithRoleAssignments{T}(IResourceBuilder{T}, IResourceBuilder{AzureAppConfigurationResource}, AppConfigurationBuiltInRole[])"/>.
    /// </remarks>
    public static IResourceBuilder<AzureAppConfigurationResource> AddAzureAppConfiguration(this IDistributedApplicationBuilder builder, [ResourceName] string name)
    {
        ArgumentNullException.ThrowIfNull(builder);
        ArgumentException.ThrowIfNullOrEmpty(name);
 
        builder.AddAzureProvisioning();
 
        var configureInfrastructure = (AzureResourceInfrastructure infrastructure) =>
        {
            var store = AzureProvisioningResource.CreateExistingOrNewProvisionableResource(infrastructure,
                (identifier, name) =>
                {
                    var resource = AppConfigurationStore.FromExisting(identifier);
                    resource.Name = name;
                    return resource;
                },
                (infrastructure) => new AppConfigurationStore(infrastructure.AspireResource.GetBicepIdentifier())
                {
                    SkuName = "standard",
                    DisableLocalAuth = true,
                    Tags = { { "aspire-resource-name", infrastructure.AspireResource.Name } }
                });
 
            infrastructure.Add(new ProvisioningOutput("appConfigEndpoint", typeof(string)) { Value = store.Endpoint });
 
            // We need to output name to externalize role assignments.
            infrastructure.Add(new ProvisioningOutput("name", typeof(string)) { Value = store.Name });
        };
 
        var resource = new AzureAppConfigurationResource(name, configureInfrastructure);
        return builder.AddResource(resource)
            .WithDefaultRoleAssignments(AppConfigurationBuiltInRole.GetBuiltInRoleName,
                AppConfigurationBuiltInRole.AppConfigurationDataOwner);
    }
 
    /// <summary>
    /// Assigns the specified roles to the given resource, granting it the necessary permissions
    /// on the target Azure App Configuration resource. This replaces the default role assignments for the resource.
    /// </summary>
    /// <param name="builder">The resource to which the specified roles will be assigned.</param>
    /// <param name="target">The target Azure App Configuration resource.</param>
    /// <param name="roles">The built-in App Configuration roles to be assigned.</param>
    /// <returns>The updated <see cref="IResourceBuilder{T}"/> with the applied role assignments.</returns>
    /// <example>
    /// Assigns the AppConfigurationDataReader role to the 'Projects.Api' project.
    /// <code lang="csharp">
    /// var builder = DistributedApplication.CreateBuilder(args);
    ///
    /// var appStore = builder.AddAzureAppConfiguration("appStore");
    /// 
    /// var api = builder.AddProject&lt;Projects.Api&gt;("api")
    ///   .WithRoleAssignments(appStore, AppConfigurationBuiltInRole.AppConfigurationDataReader)
    ///   .WithReference(appStore);
    /// </code>
    /// </example>
    public static IResourceBuilder<T> WithRoleAssignments<T>(
        this IResourceBuilder<T> builder,
        IResourceBuilder<AzureAppConfigurationResource> target,
        params AppConfigurationBuiltInRole[] roles)
        where T : IResource
    {
        return builder.WithRoleAssignments(target, AppConfigurationBuiltInRole.GetBuiltInRoleName, roles);
    }
}