#include <poll.h>
#include <unistd.h>

#include <iostream>

#include "aos/aos_cli_utils.h"
#include "aos/configuration.h"
#include "aos/init.h"
#include "aos/json_to_flatbuffer.h"
#include "gflags/gflags.h"
#include "glog/logging.h"

DEFINE_double(rate, -1, "Rate at which to send the message (-1 to send once).");

int main(int argc, char **argv) {
  gflags::SetUsageMessage(
      "Sends messages on arbitrary channels.\n"
      "Typical Usage: aos_send [--config path_to_config.json]"
      " channel_name message_type '{\"foo\": \"bar\"}'\n"
      "Example usage: aos_send /test aos.examples.Ping "
      "'{\"value\": 1}'\n"
      "Pipe usage: cat ping.json | aos_send /test/ aos.examples.Ping -");
  aos::InitGoogle(&argc, &argv);

  aos::CliUtilInfo cli_info;
  if (cli_info.Initialize(
          &argc, &argv,
          [&cli_info](const aos::Channel *channel) {
            return aos::configuration::ChannelIsSendableOnNode(
                channel, cli_info.event_loop->node());
          },
          "channel is sendable on node", false)) {
    return 0;
  }
  if (cli_info.found_channels.size() > 1) {
    LOG(FATAL) << "Matched multiple channels, but may only send on 1";
  }

  if (argc == 1) {
    LOG(FATAL) << "Must specify a message to send";
  }

  // Check if the user wants to use stdin (denoted by '-') or the argument
  // present in argv for the message to send. CliUtilInfo will ensure the
  // message data will be in argv[1]
  std::string_view message_to_send{argv[1]};
  std::string stdin_data;
  if (message_to_send == "-") {
    // Read in everything from stdin, blocks when there's no data on stdin
    stdin_data = std::string(std::istreambuf_iterator(std::cin), {});
    message_to_send = stdin_data;
  }

  const aos::Channel *const channel = cli_info.found_channels[0];
  const std::unique_ptr<aos::RawSender> sender =
      cli_info.event_loop->MakeRawSender(channel);
  flatbuffers::FlatBufferBuilder fbb(sender->fbb_allocator()->size(),
                                     sender->fbb_allocator());
  fbb.ForceDefaults(true);
  fbb.Finish(aos::JsonToFlatbuffer(message_to_send, channel->schema(), &fbb));

  if (FLAGS_rate < 0) {
    sender->CheckOk(sender->Send(fbb.GetSize()));
  } else {
    cli_info.event_loop
        ->AddTimer([&fbb, &sender]() {
          sender->CheckOk(sender->Send(fbb.GetBufferPointer(), fbb.GetSize()));
        })
        ->Setup(cli_info.event_loop->monotonic_now(),
                std::chrono::duration_cast<std::chrono::nanoseconds>(
                    std::chrono::duration<double>(1.0 / FLAGS_rate)));
    cli_info.event_loop->Run();
  }

  return 0;
}