using LmxFakeProxy;
using LmxFakeProxy.Bridge;
using LmxFakeProxy.Services;
using LmxFakeProxy.Sessions;

var builder = WebApplication.CreateBuilder(args);

// Configuration: env vars take precedence over CLI args
var port = Environment.GetEnvironmentVariable("PORT") ?? GetArg(args, "--port") ?? "50051";
var opcEndpoint = Environment.GetEnvironmentVariable("OPC_ENDPOINT") ?? GetArg(args, "--opc-endpoint") ?? "opc.tcp://localhost:50000";
var opcPrefix = Environment.GetEnvironmentVariable("OPC_PREFIX") ?? GetArg(args, "--opc-prefix") ?? "ns=3;s=";
var apiKey = Environment.GetEnvironmentVariable("API_KEY") ?? GetArg(args, "--api-key");

builder.WebHost.ConfigureKestrel(options =>
{
    options.ListenAnyIP(int.Parse(port), listenOptions =>
    {
        listenOptions.Protocols = Microsoft.AspNetCore.Server.Kestrel.Core.HttpProtocols.Http2;
    });
});

// Register services
builder.Services.AddSingleton(new SessionManager(apiKey));
builder.Services.AddSingleton(new TagMapper(opcPrefix));
builder.Services.AddSingleton<IOpcUaBridge>(sp =>
    new OpcUaBridge(opcEndpoint, sp.GetRequiredService<ILogger<OpcUaBridge>>()));
builder.Services.AddGrpc();

var app = builder.Build();

app.MapGrpcService<ScadaServiceImpl>();
app.MapGet("/", () => "LmxFakeProxy is running");

// Connect to OPC UA backend
var logger = app.Services.GetRequiredService<ILogger<Program>>();
logger.LogInformation("LmxFakeProxy starting on port {Port}", port);
logger.LogInformation("OPC UA endpoint: {Endpoint}, prefix: {Prefix}", opcEndpoint, opcPrefix);
logger.LogInformation("API key enforcement: {Enforced}", apiKey != null ? "enabled" : "disabled (accept all)");

var bridge = app.Services.GetRequiredService<IOpcUaBridge>();
try
{
    await ((OpcUaBridge)bridge).ConnectAsync();
    logger.LogInformation("OPC UA bridge connected");
}
catch (Exception ex)
{
    logger.LogWarning(ex, "Initial OPC UA connection failed — will retry when first request arrives");
}

await app.RunAsync();

static string? GetArg(string[] args, string name)
{
    var idx = Array.IndexOf(args, name);
    return idx >= 0 && idx + 1 < args.Length ? args[idx + 1] : null;
}