package ai.nomyo;

import ai.nomyo.errors.*;
import lombok.Getter;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.ExecutionException;

/**
 * High-level OpenAI-compatible entrypoint with automatic hybrid encryption (AES-256-GCM + RSA-4096).
 */
@Getter
public class SecureChatCompletion {

    private final SecureCompletionClient client;
    private final String apiKey;
    private final String keyDir;

    /**
     * Default settings: {@code https://api.nomyo.ai}, HTTPS-only, secure memory, ephemeral keys, 2 retries.
     */
    public SecureChatCompletion() {
        this(Constants.DEFAULT_BASE_URL, false, null, true, null, Constants.DEFAULT_MAX_RETRIES);
    }

    public SecureChatCompletion(String baseUrl, String apiKey) {
        this(baseUrl, false, apiKey, true, null, Constants.DEFAULT_MAX_RETRIES);
    }

    public SecureChatCompletion(String baseUrl, String apiKey, boolean allowHttp) {
        this(baseUrl, allowHttp, apiKey, true, null, Constants.DEFAULT_MAX_RETRIES);
    }

    public SecureChatCompletion(String baseUrl) {
        this(baseUrl, false, null, true, null, Constants.DEFAULT_MAX_RETRIES);
    }

    /**
     * @param baseUrl      NOMYO Router base URL (HTTPS enforced unless {@code allowHttp})
     * @param allowHttp    permit {@code http://} URLs (development only)
     * @param apiKey       Bearer token (can also be passed per-call via {@link #create})
     * @param secureMemory enable memory locking/zeroing
     * @param keyDir       RSA key directory; {@code null} = ephemeral
     * @param maxRetries   retries on 429/500/502/503/504 + network errors (exponential backoff)
     */
    public SecureChatCompletion(String baseUrl, boolean allowHttp, String apiKey, boolean secureMemory, String keyDir, int maxRetries) {
        this.client = new SecureCompletionClient(baseUrl, allowHttp, secureMemory, maxRetries);
        this.apiKey = apiKey;
        this.keyDir = keyDir;
    }

    /**
     * Main entrypoint — same signature as {@code openai.ChatCompletion.create()}.
     * All kwargs are passed through to the OpenAI-compatible API.
     * <p>Streaming is <b>not supported</b> (server rejects with HTTP 400).
     * Security tiers: "standard", "high", "maximum".
     *
     * @param model    model identifier (required)
     * @param messages OpenAI-format message list (required)
     * @param kwargs   additional OpenAI-compatible params (temperature, maxTokens, etc.)
     * @return decrypted response map
     * @throws SecurityError           encryption/decryption failure
     * @throws APIConnectionError      network error
     * @throws InvalidRequestError     HTTP 400
     * @throws AuthenticationError     HTTP 401
     * @throws ForbiddenError          HTTP 403
     * @throws RateLimitError          HTTP 429
     * @throws ServerError             HTTP 500
     * @throws ServiceUnavailableError HTTP 503
     * @throws APIError                other errors
     */
    @SuppressWarnings({"JavadocDeclaration"})
    public Map<String, Object> create(String model, List<Map<String, Object>> messages, Map<String, Object> kwargs) {
        // Validate required parameters
        if (model == null || model.isEmpty()) {
            throw new IllegalArgumentException("model is required");
        }
        if (messages == null || messages.isEmpty()) {
            throw new IllegalArgumentException("messages is required and cannot be empty");
        }

        // Build payload
        Map<String, Object> payload = new HashMap<>();
        payload.put("model", model);
        payload.put("messages", messages);

        // Add kwargs
        if (kwargs != null) {
            // Check for stream parameter
            if (kwargs.containsKey("stream")) {
                Object streamValue = kwargs.get("stream");
                boolean stream = streamValue instanceof Boolean ? (Boolean) streamValue : Boolean.parseBoolean(streamValue.toString());
                if (stream) {
                    throw new IllegalArgumentException("Streaming is not supported");
                }
            }

            // Check for security_tier
            if (kwargs.containsKey("security_tier")) {
                Object tier = kwargs.get("security_tier");
                if (tier != null && !Constants.VALID_SECURITY_TIERS.contains(tier.toString())) {
                    throw new IllegalArgumentException(
                        "Invalid security_tier: '" + tier + "'. Must be one of: " + Constants.VALID_SECURITY_TIERS);
                }
            }

            payload.putAll(kwargs);
        }

        // Determine API key (per-call override or instance key)
        String apiKey = this.apiKey;
        if (kwargs != null && kwargs.containsKey("api_key")) {
            Object key = kwargs.get("api_key");
            if (key != null) {
                apiKey = key.toString();
            }
        }

        // Determine security tier
        String securityTier = null;
        if (kwargs != null && kwargs.containsKey("security_tier")) {
            securityTier = kwargs.get("security_tier").toString();
        }

        // Generate payload ID
        String payloadId = UUID.randomUUID().toString();

        // Send secure request
        try {
            return client.sendSecureRequest(payload, payloadId, apiKey, securityTier).get();
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            throw new RuntimeException("Request interrupted", e);
        } catch (ExecutionException e) {
            Throwable cause = e.getCause();
            if (cause instanceof SecureCompletionClient.ValueError) {
                throw new IllegalArgumentException(cause);
            }
            throw new RuntimeException(cause);
        }
    }

    /**
     * Convenience variant with no additional parameters.
     */
    @SuppressWarnings("UnusedReturnValue")
    public Map<String, Object> create(String model, List<Map<String, Object>> messages) {
        return create(model, messages, null);
    }

    /**
     * Delegates to {@link SecureCompletionClient#close()}.
     */
    public void close() {
        client.close();
    }
}