package me.bill.fakePlayerPlugin.util;

import com.google.gson.JsonObject;
import me.bill.fakePlayerPlugin.FakePlayerPlugin;
import me.bill.fakePlayerPlugin.config.Config;
import me.bill.fakePlayerPlugin.fakeplayer.FakePlayerManager;
import org.bukkit.Bukkit;
import org.bukkit.plugin.Plugin;

import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URI;
import java.nio.charset.StandardCharsets;

public final class HeartbeatSender {

  private static final String ENDPOINT =
      "https://fpp.wtf/api/heartbeat";
  private static final long INTERVAL_TICKS = 20L * 30L; // 30 seconds

  private final Plugin plugin;
  private final FakePlayerManager fakePlayerManager;
  private int taskId = -1;

  public HeartbeatSender(FakePlayerPlugin plugin, FakePlayerManager fakePlayerManager) {
    this.plugin = plugin;
    this.fakePlayerManager = fakePlayerManager;
  }

  public void start() {
    if (!Config.heartbeatEnabled()) {
      Config.debug("Heartbeat: disabled in config.");
      return;
    }
    if (taskId != -1) {
      return;
    }
    taskId =
        FppScheduler.runSyncRepeatingWithId(
            plugin, this::send, INTERVAL_TICKS, INTERVAL_TICKS);
    Config.debug("Heartbeat: started (every " + (INTERVAL_TICKS / 20) + "s).");
  }

  public void stop() {
    if (taskId != -1) {
      FppScheduler.cancelTask(taskId);
      taskId = -1;
      Config.debug("Heartbeat: stopped.");
    }
  }

  private void send() {
    if (!Config.heartbeatEnabled()) return;
    FppScheduler.runAsync(plugin, this::sendBlocking);
  }

  private void sendBlocking() {
    try {
      String configuredId = Config.serverId();
      int totalOnline = Bukkit.getOnlinePlayers().size();
      int botCount = fakePlayerManager == null ? 0 : fakePlayerManager.getCount();
      // Bots are real ServerPlayer entities and appear in getOnlinePlayers(),
      // so subtract them so the web dashboard shows *real* human players.
      int playerCount = Math.max(0, totalOnline - botCount);
      String version = plugin.getPluginMeta().getVersion();

      // If server_id is the generic "default", make it unique per JVM
      // by appending IP:port. This prevents multiple backend servers from
      // overwriting each other in the web dashboard.
      String serverId = configuredId;
      if ("default".equalsIgnoreCase(configuredId) || configuredId.isBlank()) {
        String ip = Bukkit.getServer().getIp();
        int port = Bukkit.getServer().getPort();
        serverId = "default@" + (ip.isEmpty() ? "0.0.0.0" : ip) + ":" + port;
      }

      JsonObject payload = new JsonObject();
      payload.addProperty("server_id", serverId);
      payload.addProperty("player_count", playerCount);
      payload.addProperty("bot_count", botCount);
      payload.addProperty("version", version);

      byte[] body = payload.toString().getBytes(StandardCharsets.UTF_8);

      HttpURLConnection conn =
          (HttpURLConnection) URI.create(ENDPOINT).toURL().openConnection();
      conn.setRequestMethod("POST");
      conn.setConnectTimeout(5_000);
      conn.setReadTimeout(5_000);
      conn.setDoOutput(true);
      conn.setRequestProperty("Content-Type", "application/json");
      conn.setRequestProperty("Content-Length", String.valueOf(body.length));
      conn.setRequestProperty(
          "User-Agent",
          "FakePlayerPlugin-Heartbeat/" + version + " (https://fpp.wtf)");

      try (OutputStream out = conn.getOutputStream()) {
        out.write(body);
      }

      int code = conn.getResponseCode();
      Config.debug(
          "Heartbeat: sent (players="
              + playerCount
              + ", bots="
              + botCount
              + ", server="
              + serverId
              + ") → HTTP "
              + code);
    } catch (Exception e) {
      Config.debug("Heartbeat: failed - " + e.getClass().getSimpleName() + ": " + e.getMessage());
    }
  }
}