// 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 Azure.Provisioning.ApplicationInsights;
using Azure.Provisioning.Primitives;
 
namespace Aspire.Hosting.Azure;
 
/// <summary>
/// A resource that represents an Azure Application Insights resource.
/// </summary>
/// <param name="name">The resource name.</param>
/// <param name="configureInfrastructure">Callback to configure the Azure Application Insights resource.</param>
public class AzureApplicationInsightsResource(string name, Action<AzureResourceInfrastructure> configureInfrastructure)
    : AzureProvisioningResource(name, configureInfrastructure),
    IResourceWithConnectionString
{
    /// <summary>
    /// Gets the "name" output reference for the resource.
    /// </summary>
    public BicepOutputReference NameOutputReference => new("name", this);
 
    /// <summary>
    /// Gets the "appInsightsConnectionString" output reference for the Azure Application Insights resource.
    /// </summary>
    public BicepOutputReference ConnectionString => new("appInsightsConnectionString", this);
 
    /// <summary>
    /// Gets the connection string template for the manifest for the Azure Application Insights resource.
    /// </summary>
    public ReferenceExpression ConnectionStringExpression =>
        ReferenceExpression.Create($"{ConnectionString}");
 
    // UseAzureMonitor is looks for this specific environment variable name.
    string IResourceWithConnectionString.ConnectionStringEnvironmentVariable => "APPLICATIONINSIGHTS_CONNECTION_STRING";
 
    /// <inheritdoc/>
    public override ProvisionableResource AddAsExistingResource(AzureResourceInfrastructure infra)
    {
        var bicepIdentifier = this.GetBicepIdentifier();
        var resources = infra.GetProvisionableResources();
 
        // Check if a ApplicationInsightsComponent with the same identifier already exists
        var existingStore = resources.OfType<ApplicationInsightsComponent>().SingleOrDefault(store => store.BicepIdentifier == bicepIdentifier);
 
        if (existingStore is not null)
        {
            return existingStore;
        }
 
        // Create and add new resource if it doesn't exist
        var store = ApplicationInsightsComponent.FromExisting(bicepIdentifier);
 
        if (!TryApplyExistingResourceAnnotation(
            this,
            infra,
            store))
        {
            store.Name = NameOutputReference.AsProvisioningParameter(infra);
        }
 
        infra.Add(store);
        return store;
    }
}