package org.saturnclient.client;

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.util.UUID;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

/**
 * Mojang's session server "join" call, the same one vanilla makes when joining
 * an online-mode server. The access token is only ever sent to Mojang; the
 * Saturn server then confirms the join with {@code hasJoined}.
 */
public final class MojangSession {
    private static final URI JOIN_URI = URI.create("https://sessionserver.mojang.com/session/minecraft/join");
    private static final ObjectMapper MAPPER = new ObjectMapper();

    public enum JoinResult {
        JOINED,
        /** Mojang refused the access token; retrying won't help. */
        REJECTED,
        /** Network or server error; worth retrying. */
        FAILED
    }

    private MojangSession() {
    }

    public static JoinResult join(HttpClient http, String accessToken, UUID profile, String serverId) {
        ObjectNode body = MAPPER.createObjectNode()
                .put("accessToken", accessToken)
                .put("selectedProfile", profile.toString().replace("-", ""))
                .put("serverId", serverId);

        HttpRequest request = HttpRequest.newBuilder(JOIN_URI)
                .timeout(Duration.ofSeconds(10))
                .header("Content-Type", "application/json")
                .POST(HttpRequest.BodyPublishers.ofString(body.toString()))
                .build();

        try {
            int status = http.send(request, HttpResponse.BodyHandlers.discarding()).statusCode();

            if (status == 204 || status == 200) {
                return JoinResult.JOINED;
            }

            return status == 401 || status == 403 ? JoinResult.REJECTED : JoinResult.FAILED;
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            return JoinResult.FAILED;
        } catch (Exception e) {
            return JoinResult.FAILED;
        }
    }
}