using System.Data;
using System.Text.Json;
using Confluent.Kafka;
using Dapper;
using GeoPulse_Pipeline;
using Microsoft.AspNetCore.Mvc;
using Npgsql;

var builder = WebApplication.CreateBuilder(args);
var kafkaHost = builder.Configuration.GetValue<string>("KafkaHost");
var producerConfig = new ProducerConfig()
{
	BootstrapServers = kafkaHost,
	Acks = Acks.Leader
};

var connString = builder.Configuration.GetConnectionString("DefaultConnection");
var kafkaProducer = new ProducerBuilder<Null, string>(producerConfig).Build();
builder.Services.AddSingleton(kafkaProducer);
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddHostedService<KafkaConsumer>();
builder.Services.AddNpgsqlDataSource(connString);
builder.Services.AddScoped<IDbConnection>(sp => sp.GetRequiredService<NpgsqlDataSource>().CreateConnection());

var app = builder.Build();

if (app.Environment.IsDevelopment())
{
	app.UseSwagger();
	app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.MapPost("/api/telemetry", async (
	[FromBody] TelemetryRequest request,
	[FromQuery] bool useKafka,
	IProducer<Null, string> producer,
	IDbConnection dbConnection) =>
{
	if (string.IsNullOrWhiteSpace(request.DeviceId))
		return Results.BadRequest("Device ID is required.");

	if (useKafka)
	{
		var message = JsonSerializer.Serialize(request);
		try
		{
			await producer.ProduceAsync("telemetry-events", new Message<Null, string> { Value = message });
			return Results.Ok(new { Status = "Success", Route = "Kafka", Message = "已推入消息佇列" });
		}
		catch (ProduceException<Null, string> ex)
		{
			Console.WriteLine($"Kafka Delivery failed: {ex.Error.Reason}");
			return Results.Problem("Kafka 寫入失敗");
		}
	}
	else
	{
		try
		{
			string sql =
				@"INSERT INTO telemetry_history (id, device_id, geom, timestamp) VALUES (gen_random_uuid(), @DeviceId, @Lng, @Lat, @Timestamp";
			await dbConnection.ExecuteAsync(sql, request);

			return Results.Ok(new { Status = "Success", Route = "Direct-DB", Message = "已直接寫入資料庫" });
		}
		catch (Exception ex)
		{
			Console.WriteLine($"DB Insert failed: {ex.Message}");
			return Results.Problem("資料庫寫入失敗");
		}
	}
});

app.Lifetime.ApplicationStopping.Register(() =>
{
	kafkaProducer.Flush(TimeSpan.FromSeconds(10));
	kafkaProducer.Dispose();
});

app.Run();

record TelemetryRequest(string DeviceId, double Lng, double Lat, DateTimeOffset Timestamp);