/*
 * Copyright The OpenTelemetry Authors
 * SPDX-License-Identifier: Apache-2.0
 */

package io.opentelemetry.exporter.otlp.logs;

import static io.opentelemetry.api.internal.Utils.checkArgument;
import static java.util.Objects.requireNonNull;

import io.grpc.ManagedChannel;
import io.opentelemetry.api.GlobalOpenTelemetry;
import io.opentelemetry.api.metrics.MeterProvider;
import io.opentelemetry.exporter.internal.compression.Compressor;
import io.opentelemetry.exporter.internal.compression.CompressorProvider;
import io.opentelemetry.exporter.internal.compression.CompressorUtil;
import io.opentelemetry.exporter.internal.grpc.GrpcExporterBuilder;
import io.opentelemetry.exporter.internal.marshal.Marshaler;
import io.opentelemetry.exporter.otlp.internal.OtlpUserAgent;
import io.opentelemetry.sdk.common.export.MemoryMode;
import io.opentelemetry.sdk.common.export.RetryPolicy;
import java.net.URI;
import java.time.Duration;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;
import javax.annotation.Nullable;
import javax.net.ssl.SSLContext;
import javax.net.ssl.X509TrustManager;

/**
 * Builder for {@link OtlpGrpcLogRecordExporter}.
 *
 * @since 1.27.0
 */
public final class OtlpGrpcLogRecordExporterBuilder {

  private static final String GRPC_SERVICE_NAME =
      "opentelemetry.proto.collector.logs.v1.LogsService";
  // Visible for testing
  static final String GRPC_ENDPOINT_PATH = "/" + GRPC_SERVICE_NAME + "/Export";

  private static final String DEFAULT_ENDPOINT_URL = "http://localhost:4317";
  private static final URI DEFAULT_ENDPOINT = URI.create(DEFAULT_ENDPOINT_URL);
  private static final long DEFAULT_TIMEOUT_SECS = 10;
  private static final MemoryMode DEFAULT_MEMORY_MODE = MemoryMode.REUSABLE_DATA;

  // Visible for testing
  final GrpcExporterBuilder<Marshaler> delegate;
  private MemoryMode memoryMode;

  OtlpGrpcLogRecordExporterBuilder(GrpcExporterBuilder<Marshaler> delegate, MemoryMode memoryMode) {
    this.delegate = delegate;
    this.memoryMode = memoryMode;
    OtlpUserAgent.addUserAgentHeader(delegate::addConstantHeader);
  }

  OtlpGrpcLogRecordExporterBuilder() {
    this(
        new GrpcExporterBuilder<>(
            "otlp",
            "log",
            DEFAULT_TIMEOUT_SECS,
            DEFAULT_ENDPOINT,
            () -> MarshalerLogsServiceGrpc::newFutureStub,
            GRPC_ENDPOINT_PATH),
        DEFAULT_MEMORY_MODE);
  }

  /**
   * Sets the managed chanel to use when communicating with the backend. Takes precedence over
   * {@link #setEndpoint(String)} if both are called.
   *
   * <p>Note: calling this overrides the spec compliant {@code User-Agent} header. To ensure spec
   * compliance, set {@link io.grpc.ManagedChannelBuilder#userAgent(String)} to {@link
   * OtlpUserAgent#getUserAgent()} when building the channel.
   *
   * @param channel the channel to use
   * @return this builder's instance
   * @deprecated Use {@link #setEndpoint(String)}. If you have a use case not satisfied by the
   *     methods on this builder, please file an issue to let us know what it is.
   */
  @Deprecated
  public OtlpGrpcLogRecordExporterBuilder setChannel(ManagedChannel channel) {
    delegate.setChannel(channel);
    return this;
  }

  /**
   * Sets the maximum time to wait for the collector to process an exported batch of logs. If unset,
   * defaults to {@value DEFAULT_TIMEOUT_SECS}s.
   */
  public OtlpGrpcLogRecordExporterBuilder setTimeout(long timeout, TimeUnit unit) {
    requireNonNull(unit, "unit");
    checkArgument(timeout >= 0, "timeout must be non-negative");
    delegate.setTimeout(timeout, unit);
    return this;
  }

  /**
   * Sets the maximum time to wait for the collector to process an exported batch of logs. If unset,
   * defaults to {@value DEFAULT_TIMEOUT_SECS}s.
   */
  public OtlpGrpcLogRecordExporterBuilder setTimeout(Duration timeout) {
    requireNonNull(timeout, "timeout");
    delegate.setTimeout(timeout);
    return this;
  }

  /**
   * Sets the maximum time to wait for new connections to be established. If unset, defaults to
   * {@value GrpcExporterBuilder#DEFAULT_CONNECT_TIMEOUT_SECS}s.
   *
   * @since 1.36.0
   */
  public OtlpGrpcLogRecordExporterBuilder setConnectTimeout(long timeout, TimeUnit unit) {
    requireNonNull(unit, "unit");
    checkArgument(timeout >= 0, "timeout must be non-negative");
    delegate.setConnectTimeout(timeout, unit);
    return this;
  }

  /**
   * Sets the maximum time to wait for new connections to be established. If unset, defaults to
   * {@value GrpcExporterBuilder#DEFAULT_CONNECT_TIMEOUT_SECS}s.
   *
   * @since 1.36.0
   */
  public OtlpGrpcLogRecordExporterBuilder setConnectTimeout(Duration timeout) {
    requireNonNull(timeout, "timeout");
    return setConnectTimeout(timeout.toNanos(), TimeUnit.NANOSECONDS);
  }

  /**
   * Sets the OTLP endpoint to connect to. If unset, defaults to {@value DEFAULT_ENDPOINT_URL}. The
   * endpoint must start with either http:// or https://.
   */
  public OtlpGrpcLogRecordExporterBuilder setEndpoint(String endpoint) {
    requireNonNull(endpoint, "endpoint");
    delegate.setEndpoint(endpoint);
    return this;
  }

  /**
   * Sets the method used to compress payloads. If unset, compression is disabled. Compression
   * method "gzip" and "none" are supported out of the box. Support for additional compression
   * methods is available by implementing {@link Compressor} and {@link CompressorProvider}.
   */
  public OtlpGrpcLogRecordExporterBuilder setCompression(String compressionMethod) {
    requireNonNull(compressionMethod, "compressionMethod");
    Compressor compressor = CompressorUtil.validateAndResolveCompressor(compressionMethod);
    delegate.setCompression(compressor);
    return this;
  }

  /**
   * Sets the certificate chain to use for verifying servers when TLS is enabled. The {@code byte[]}
   * should contain an X.509 certificate collection in PEM format. If not set, TLS connections will
   * use the system default trusted certificates.
   */
  public OtlpGrpcLogRecordExporterBuilder setTrustedCertificates(byte[] trustedCertificatesPem) {
    delegate.setTrustManagerFromCerts(trustedCertificatesPem);
    return this;
  }

  /**
   * Sets ths client key and the certificate chain to use for verifying client when TLS is enabled.
   * The key must be PKCS8, and both must be in PEM format.
   */
  public OtlpGrpcLogRecordExporterBuilder setClientTls(
      byte[] privateKeyPem, byte[] certificatePem) {
    delegate.setKeyManagerFromCerts(privateKeyPem, certificatePem);
    return this;
  }

  /**
   * Sets the "bring-your-own" SSLContext for use with TLS. Users should call this _or_ set raw
   * certificate bytes, but not both.
   */
  public OtlpGrpcLogRecordExporterBuilder setSslContext(
      SSLContext sslContext, X509TrustManager trustManager) {
    delegate.setSslContext(sslContext, trustManager);
    return this;
  }

  /**
   * Add a constant header to requests. If the {@code key} collides with another constant header
   * name or a one from {@link #setHeaders(Supplier)}, the values from both are included. Applicable
   * only if {@link OtlpGrpcLogRecordExporterBuilder#setChannel(ManagedChannel)} is not used to set
   * channel.
   *
   * @param key header key
   * @param value header value
   * @return this builder's instance
   */
  public OtlpGrpcLogRecordExporterBuilder addHeader(String key, String value) {
    delegate.addConstantHeader(key, value);
    return this;
  }

  /**
   * Set the supplier of headers to add to requests. If a key from the map collides with a constant
   * from {@link #addHeader(String, String)}, the values from both are included. Applicable only if
   * {@link OtlpGrpcLogRecordExporterBuilder#setChannel(ManagedChannel)} is not used to set channel.
   *
   * @since 1.33.0
   */
  public OtlpGrpcLogRecordExporterBuilder setHeaders(Supplier<Map<String, String>> headerSupplier) {
    delegate.setHeadersSupplier(headerSupplier);
    return this;
  }

  /**
   * Set the retry policy, or {@code null} to disable retry. Retry policy is {@link
   * RetryPolicy#getDefault()} by default
   *
   * @since 1.28.0
   */
  public OtlpGrpcLogRecordExporterBuilder setRetryPolicy(@Nullable RetryPolicy retryPolicy) {
    delegate.setRetryPolicy(retryPolicy);
    return this;
  }

  /**
   * Sets the {@link MeterProvider} to use to collect metrics related to export. If not set, uses
   * {@link GlobalOpenTelemetry#getMeterProvider()}.
   */
  public OtlpGrpcLogRecordExporterBuilder setMeterProvider(MeterProvider meterProvider) {
    requireNonNull(meterProvider, "meterProvider");
    setMeterProvider(() -> meterProvider);
    return this;
  }

  /**
   * Sets the {@link MeterProvider} supplier used to collect metrics related to export. If not set,
   * uses {@link GlobalOpenTelemetry#getMeterProvider()}.
   *
   * @since 1.32.0
   */
  public OtlpGrpcLogRecordExporterBuilder setMeterProvider(
      Supplier<MeterProvider> meterProviderSupplier) {
    requireNonNull(meterProviderSupplier, "meterProviderSupplier");
    delegate.setMeterProvider(meterProviderSupplier);
    return this;
  }

  /**
   * Set the {@link MemoryMode}. If unset, defaults to {@link #DEFAULT_MEMORY_MODE}.
   *
   * <p>When memory mode is {@link MemoryMode#REUSABLE_DATA}, serialization is optimized to reduce
   * memory allocation.
   *
   * @since 1.39.0
   */
  public OtlpGrpcLogRecordExporterBuilder setMemoryMode(MemoryMode memoryMode) {
    requireNonNull(memoryMode, "memoryMode");
    this.memoryMode = memoryMode;
    return this;
  }

  /**
   * Set the {@link ClassLoader} used to load the sender API.
   *
   * @since 1.48.0
   */
  public OtlpGrpcLogRecordExporterBuilder setServiceClassLoader(ClassLoader serviceClassLoader) {
    requireNonNull(serviceClassLoader, "serviceClassLoader");
    delegate.setServiceClassLoader(serviceClassLoader);
    return this;
  }

  /**
   * Set the {@link ExecutorService} used to execute requests.
   *
   * <p>NOTE: By calling this method, you are opting into managing the lifecycle of the {@code
   * executorService}. {@link ExecutorService#shutdown()} will NOT be called when this exporter is
   * shutdown.
   */
  public OtlpGrpcLogRecordExporterBuilder setExecutorService(ExecutorService executorService) {
    requireNonNull(executorService, "executorService");
    delegate.setExecutorService(executorService);
    return this;
  }

  /**
   * Constructs a new instance of the exporter based on the builder's values.
   *
   * @return a new exporter's instance
   */
  public OtlpGrpcLogRecordExporter build() {
    return new OtlpGrpcLogRecordExporter(delegate, delegate.build(), memoryMode);
  }
}
