// Copyright (c) Microsoft. All rights reserved.

using System.ComponentModel;
using AGUIServer;
using Azure.AI.OpenAI;
using Azure.Identity;
using Microsoft.Agents.AI.Hosting;
using Microsoft.Agents.AI.Hosting.AGUI.AspNetCore;
using Microsoft.Extensions.AI;
using OpenAI.Chat;

WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
builder.Services.AddHttpClient().AddLogging();
builder.Services.ConfigureHttpJsonOptions(options => options.SerializerOptions.TypeInfoResolverChain.Add(AGUIServerSerializerContext.Default));
builder.Services.AddAGUIServer();

string endpoint = builder.Configuration["AZURE_OPENAI_ENDPOINT"] ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");
string deploymentName = builder.Configuration["AZURE_OPENAI_DEPLOYMENT_NAME"] ?? throw new InvalidOperationException("AZURE_OPENAI_DEPLOYMENT_NAME is not set.");

const string AgentName = "AGUIAssistant";

// Create the AI agent with tools
// WARNING: DefaultAzureCredential is convenient for development but requires careful consideration in production.
// In production, consider using a specific credential (e.g., ManagedIdentityCredential) to avoid
// latency issues, unintended credential probing, and potential security risks from fallback mechanisms.
var agent = new AzureOpenAIClient(
        new Uri(endpoint),
        new DefaultAzureCredential())
    .GetChatClient(deploymentName)
    .AsAIAgent(
        name: AgentName,
        tools: [
            AIFunctionFactory.Create(
                () => DateTimeOffset.UtcNow,
                name: "get_current_time",
                description: "Get the current UTC time."
            ),
            AIFunctionFactory.Create(
                ([Description("The weather forecast request")]ServerWeatherForecastRequest request) => {
                    return new ServerWeatherForecastResponse()
                    {
                        Summary = "Sunny",
                        TemperatureC = 25,
                        Date = request.Date
                    };
                },
                name: "get_server_weather_forecast",
                description: "Gets the forecast for a specific location and date",
                AGUIServerSerializerContext.Default.Options)
        ]);

// WARNING: When adding session persistence (e.g., WithInMemorySessionStore), or running in production,
// make sure to also register a SessionIsolationKeyProvider to scope sessions by principal in multi-user
// deployments, e.g.:
// builder.Services.UseClaimsBasedSessionIsolation(new() { ClaimType = ClaimTypes.NameIdentifier });

// Register the agent with the host and configure it to use an in-memory session store
// so that conversation state is maintained across requests. In production, you may want to use a persistent session store.
builder
    .AddAIAgent(AgentName, (_, _) => agent)
    .WithInMemorySessionStore();

WebApplication app = builder.Build();

// Map the AG-UI agent endpoint
app.MapAGUIServer(AgentName, "/");

await app.RunAsync();