package org.stellar.sdk;

import com.google.gson.reflect.TypeToken;
import okhttp3.*;
import okhttp3.Response;
import org.stellar.sdk.requests.*;
import org.stellar.sdk.responses.*;

import java.io.IOException;
import java.net.SocketTimeoutException;
import java.util.concurrent.TimeUnit;

/**
 * Main class used to connect to Horizon server.
 */
public class Server {
    private HttpUrl serverURI;
    private OkHttpClient httpClient;
    /**
     * submitHttpClient is used only for submitting transactions. The read timeout is longer.
     */
    private OkHttpClient submitHttpClient;

    /**
     * HORIZON_SUBMIT_TIMEOUT is a time in seconds after Horizon sends a timeout response
     * after internal txsub timeout.
     */
    private static final int HORIZON_SUBMIT_TIMEOUT = 60;

    public Server(String uri) {
        serverURI = HttpUrl.parse(uri);
        httpClient = new OkHttpClient.Builder()
                .connectTimeout(10, TimeUnit.SECONDS)
                .readTimeout(30, TimeUnit.SECONDS)
                .retryOnConnectionFailure(true)
                .build();

        submitHttpClient = new OkHttpClient.Builder()
                .connectTimeout(10, TimeUnit.SECONDS)
                .readTimeout(HORIZON_SUBMIT_TIMEOUT + 5, TimeUnit.SECONDS)
                .retryOnConnectionFailure(true)
                .build();
    }


    public OkHttpClient getHttpClient() {
        return httpClient;
    }

    public OkHttpClient getSubmitHttpClient() {
        return submitHttpClient;
    }

    public void setHttpClient(OkHttpClient httpClient) {
        this.httpClient = httpClient;
    }

    public void setSubmitHttpClient(OkHttpClient submitHttpClient) {
        this.submitHttpClient = submitHttpClient;
    }

    /**
     * Returns {@link RootResponse}.
     */
    public RootResponse root() throws IOException {
        TypeToken type = new TypeToken<RootResponse>() {};
        ResponseHandler<RootResponse> responseHandler = new ResponseHandler<RootResponse>(type);

        Request request = new Request.Builder().get().url(serverURI).build();
        Response response = httpClient.newCall(request).execute();

        return responseHandler.handleResponse(response);
    }

    /**
     * Returns {@link AccountsRequestBuilder} instance.
     */
    public AccountsRequestBuilder accounts() {
        return new AccountsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link AssetsRequestBuilder} instance.
     */
    public AssetsRequestBuilder assets() {
        return new AssetsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link EffectsRequestBuilder} instance.
     */
    public EffectsRequestBuilder effects() {
        return new EffectsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link LedgersRequestBuilder} instance.
     */
    public LedgersRequestBuilder ledgers() {
        return new LedgersRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link OffersRequestBuilder} instance.
     */
    public OffersRequestBuilder offers() {
        return new OffersRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link OperationsRequestBuilder} instance.
     */
    public OperationsRequestBuilder operations() {
        return new OperationsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link OperationFeeStatsResponse} instance.
     */
    public OperationFeeStatsRequestBuilder operationFeeStats() {
        return new OperationFeeStatsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link OrderBookRequestBuilder} instance.
     */
    public OrderBookRequestBuilder orderBook() {
        return new OrderBookRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link TradesRequestBuilder} instance.
     */
    public TradesRequestBuilder trades() {
        return new TradesRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link TradeAggregationsRequestBuilder} instance.
     */
    public TradeAggregationsRequestBuilder tradeAggregations(Asset baseAsset, Asset counterAsset, long startTime, long endTime, long resolution, long offset) {
        return new TradeAggregationsRequestBuilder(httpClient, serverURI, baseAsset, counterAsset, startTime, endTime, resolution, offset);
    }

    /**
     * Returns {@link PathsRequestBuilder} instance.
     */
    public PathsRequestBuilder paths() {
        return new PathsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link PaymentsRequestBuilder} instance.
     */
    public PaymentsRequestBuilder payments() {
        return new PaymentsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Returns {@link TransactionsRequestBuilder} instance.
     */
    public TransactionsRequestBuilder transactions() {
        return new TransactionsRequestBuilder(httpClient, serverURI);
    }

    /**
     * Submits transaction to the network.
     * @param transaction transaction to submit to the network.
     * @return {@link SubmitTransactionResponse}
     * @throws SubmitTransactionTimeoutResponseException When Horizon returns a <code>Timeout</code> or connection timeout occured.
     * @throws SubmitTransactionUnknownResponseException When unknown Horizon response is returned.
     * @throws IOException
     */
    public SubmitTransactionResponse submitTransaction(Transaction transaction) throws IOException {
        HttpUrl transactionsURI = serverURI.newBuilder().addPathSegment("transactions").build();
        RequestBody requestBody = new FormBody.Builder().add("tx", transaction.toEnvelopeXdrBase64()).build();
        Request submitTransactionRequest = new Request.Builder().url(transactionsURI).post(requestBody).build();

        Response response = null;
        SubmitTransactionResponse submitTransactionResponse = null;
        try {
            response = this.submitHttpClient.newCall(submitTransactionRequest).execute();
            switch (response.code()) {
                case 200:
                case 400:
                    submitTransactionResponse = GsonSingleton.getInstance().fromJson(response.body().string(), SubmitTransactionResponse.class);
                    break;
                case 504:
                    throw new SubmitTransactionTimeoutResponseException();
                default:
                    throw new SubmitTransactionUnknownResponseException(response.code(), response.body().string());
            }
        } catch (SocketTimeoutException e) {
            throw new SubmitTransactionTimeoutResponseException();
        } finally {
            if (response != null) {
                response.close();
            }
        }

        return submitTransactionResponse;
    }
}