/*

 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/*
  A command line tool to talk to a grpc server.
  Example of talking to grpc interop server:
  grpc_cli call localhost:50051 UnaryCall src/proto/grpc/testing/test.proto \
    "response_size:10"  --enable_ssl=false

  Options:
    1. --proto_path, if your proto file is not under current working directory,
       use this flag to provide a search root. It should work similar to the
       counterpart in protoc.
    2. --metadata specifies metadata to be sent to the server, such as:
       --metadata="MyHeaderKey1:Value1:MyHeaderKey2:Value2"
    3. --enable_ssl, whether to use tls.
    4. --use_auth, if set to true, attach a GoogleDefaultCredentials to the call
    3. --input_binary_file, a file containing the serialized request. The file
       can be generated by calling something like:
       protoc --proto_path=src/proto/grpc/testing/ \
         --encode=grpc.testing.SimpleRequest \
         src/proto/grpc/testing/messages.proto \
         < input.txt > input.bin
       If this is used and no proto file is provided in the argument list, the
       method string has to be exact in the form of /package.service/method.
    4. --output_binary_file, a file to write binary format response into, it can
       be later decoded using protoc:
       protoc --proto_path=src/proto/grpc/testing/ \
       --decode=grpc.testing.SimpleResponse \
       src/proto/grpc/testing/messages.proto \
       < output.bin > output.txt
*/

#include <fstream>
#include <iostream>
#include <sstream>

#include <gflags/gflags.h>
#include <grpc++/channel.h>
#include <grpc++/create_channel.h>
#include <grpc++/security/credentials.h>
#include <grpc++/support/string_ref.h>
#include <grpc/grpc.h>

#include "test/cpp/util/cli_call.h"
#include "test/cpp/util/proto_file_parser.h"
#include "test/cpp/util/string_ref_helper.h"
#include "test/cpp/util/test_config.h"

DEFINE_bool(enable_ssl, true, "Whether to use ssl/tls.");
DEFINE_bool(use_auth, false, "Whether to create default google credentials.");
DEFINE_string(input_binary_file, "",
              "Path to input file containing serialized request.");
DEFINE_string(output_binary_file, "",
              "Path to output file to write serialized response.");
DEFINE_string(metadata, "",
              "Metadata to send to server, in the form of key1:val1:key2:val2");
DEFINE_string(proto_path, ".", "Path to look for the proto file.");

void ParseMetadataFlag(
    std::multimap<grpc::string, grpc::string>* client_metadata) {
  if (FLAGS_metadata.empty()) {
    return;
  }
  std::vector<grpc::string> fields;
  const char* delim = ":";
  size_t cur, next = -1;
  do {
    cur = next + 1;
    next = FLAGS_metadata.find_first_of(delim, cur);
    fields.push_back(FLAGS_metadata.substr(cur, next - cur));
  } while (next != grpc::string::npos);
  if (fields.size() % 2) {
    std::cout << "Failed to parse metadata flag" << std::endl;
    exit(1);
  }
  for (size_t i = 0; i < fields.size(); i += 2) {
    client_metadata->insert(
        std::pair<grpc::string, grpc::string>(fields[i], fields[i + 1]));
  }
}

template <typename T>
void PrintMetadata(const T& m, const grpc::string& message) {
  if (m.empty()) {
    return;
  }
  std::cout << message << std::endl;
  grpc::string pair;
  for (typename T::const_iterator iter = m.begin(); iter != m.end(); ++iter) {
    pair.clear();
    pair.append(iter->first.data(), iter->first.size());
    pair.append(" : ");
    pair.append(iter->second.data(), iter->second.size());
    std::cout << pair << std::endl;
  }
}

int main(int argc, char** argv) {
  grpc::testing::InitTest(&argc, &argv, true);

  if (argc < 4 || argc == 5 || grpc::string(argv[1]) != "call") {
    std::cout << "Usage: grpc_cli call server_host:port method_name "
              << "[proto file] [text format request] [<options>]" << std::endl;
  }

  grpc::string file_name;
  grpc::string request_text;
  grpc::string server_address(argv[2]);
  grpc::string method_name(argv[3]);
  std::unique_ptr<grpc::testing::ProtoFileParser> parser;
  grpc::string serialized_request_proto;

  if (argc == 6) {
    file_name = argv[4];
    // TODO(yangg) read from stdin as well?
    request_text = argv[5];
  }

  if (request_text.empty() && FLAGS_input_binary_file.empty()) {
    std::cout << "Missing input. Use text format input or "
              << "--input_binary_file for serialized request" << std::endl;
    return 1;
  } else if (!request_text.empty()) {
    parser.reset(new grpc::testing::ProtoFileParser(FLAGS_proto_path, file_name,
                                                    method_name));
    method_name = parser->GetFullMethodName();
    if (parser->HasError()) {
      return 1;
    }
  }

  if (parser) {
    serialized_request_proto =
        parser->GetSerializedProto(request_text, true /* is_request */);
    if (parser->HasError()) {
      return 1;
    }
  } else if (!FLAGS_input_binary_file.empty()) {
    std::ifstream input_file(FLAGS_input_binary_file,
                             std::ios::in | std::ios::binary);
    std::stringstream input_stream;
    input_stream << input_file.rdbuf();
    serialized_request_proto = input_stream.str();
  }
  std::cout << "connecting to " << server_address << std::endl;

  std::shared_ptr<grpc::ChannelCredentials> creds;
  if (!FLAGS_enable_ssl) {
    creds = grpc::InsecureChannelCredentials();
  } else {
    if (FLAGS_use_auth) {
      creds = grpc::GoogleDefaultCredentials();
    } else {
      creds = grpc::SslCredentials(grpc::SslCredentialsOptions());
    }
  }
  std::shared_ptr<grpc::Channel> channel =
      grpc::CreateChannel(server_address, creds);

  grpc::string serialized_response_proto;
  std::multimap<grpc::string, grpc::string> client_metadata;
  std::multimap<grpc::string_ref, grpc::string_ref> server_initial_metadata,
      server_trailing_metadata;
  ParseMetadataFlag(&client_metadata);
  PrintMetadata(client_metadata, "Sending client initial metadata:");
  grpc::Status s = grpc::testing::CliCall::Call(
      channel, method_name, serialized_request_proto,
      &serialized_response_proto, client_metadata, &server_initial_metadata,
      &server_trailing_metadata);
  PrintMetadata(server_initial_metadata,
                "Received initial metadata from server:");
  PrintMetadata(server_trailing_metadata,
                "Received trailing metadata from server:");
  if (s.ok()) {
    std::cout << "Rpc succeeded with OK status" << std::endl;
    if (parser) {
      grpc::string response_text = parser->GetTextFormat(
          serialized_response_proto, false /* is_request */);
      if (parser->HasError()) {
        return 1;
      }
      std::cout << "Response: \n " << response_text << std::endl;
    }
    if (!FLAGS_output_binary_file.empty()) {
      std::ofstream output_file(FLAGS_output_binary_file,
                                std::ios::trunc | std::ios::binary);
      output_file << serialized_response_proto;
    }
  } else {
    std::cout << "Rpc failed with status code " << s.error_code()
              << " error message " << s.error_message() << std::endl;
  }

  return 0;
}