#include "common/bigint.hpp"
#include "common/refint.h"
#include "block/block.h"
#include "td/utils/benchmark.h"
#include "td/utils/filesystem.h"
#include "vm/boc.h"
#include "openssl/digest.hpp"
#include <openssl/sha.h>
#include <iostream>
#include <thread>
#include <cstdlib>
#include <getopt.h>

#include "Miner.h"

const char* progname;

int usage() {
  std::cerr
      << "usage: " << progname
      << " [-v][-B][-w<threads>] [-t<timeout>] <my-address> <pow-seed> <pow-complexity> <iterations> [<miner-addr> "
         "<output-ext-msg-boc>]\n"
         "Outputs a valid <rdata> value for proof-of-work testgiver after computing at most <iterations> hashes "
         "or terminates with non-zero exit code\n";
  std::exit(2);
}

td::RefInt256 parse_bigint(std::string str, int bits) {
  int len = (int)str.size();
  auto num = td::make_refint();
  auto& x = num.write();
  if (len >= 3 && str[0] == '0' && str[1] == 'x') {
    if (x.parse_hex(str.data() + 2, len - 2) != len - 2) {
      return {};
    }
  } else if (!len || x.parse_dec(str.data(), len) != len) {
    return {};
  }
  return x.unsigned_fits_bits(bits) ? std::move(num) : td::RefInt256{};
}

td::RefInt256 parse_bigint_chk(std::string str, int bits) {
  auto x = parse_bigint(std::move(str), bits);
  if (x.is_null()) {
    std::cerr << "fatal: `" << str << "` is not an integer" << std::endl;
    usage();
  }
  return x;
}

void parse_addr(std::string str, block::StdAddress& addr) {
  if (!addr.parse_addr(str) || (addr.workchain != -1 && addr.workchain != 0)) {
    std::cerr << "fatal: `" << str.c_str() << "` is not a valid blockchain address" << std::endl;
    usage();
  }
}

bool make_boc = false;
std::string boc_filename;
block::StdAddress miner_address;

int verbosity = 0;
std::atomic<td::uint64> hashes_computed{0};
td::Timestamp start_at;

void print_stats() {
  auto passed = td::Timestamp::now().at() - start_at.at();
  if (passed < 1e-9) {
    passed = 1;
  }
  std::cerr << "[ hashes computed: " << hashes_computed << " ]" << std::endl;
  std::cerr << "[ speed: " << static_cast<double>(hashes_computed) / passed << " hps ]" << std::endl;
}

int found(td::Slice data) {
  for (unsigned i = 0; i < data.size(); i++) {
    printf("%02X", data.ubegin()[i]);
  }
  printf("\n");
  if (make_boc) {
    vm::CellBuilder cb;
    td::Ref<vm::Cell> ext_msg, body;
    CHECK(cb.store_bytes_bool(data)                              // body
          && cb.finalize_to(body)                                // -> body
          && cb.store_long_bool(0x44, 7)                         // ext_message_in$10 ...
          && cb.store_long_bool(miner_address.workchain, 8)      // workchain
          && cb.store_bytes_bool(miner_address.addr.as_slice())  // miner addr
          && cb.store_long_bool(1, 6)                            // amount:Grams ...
          && cb.store_ref_bool(std::move(body))                  // body:^Cell
          && cb.finalize_to(ext_msg));
    auto boc = vm::std_boc_serialize(std::move(ext_msg), 2).move_as_ok();
    std::cerr << "Saving " << boc.size() << " bytes of serialized external message into file `" << boc_filename << "`"
              << std::endl;
    td::write_file(boc_filename, boc).ensure();
  }
  if (verbosity > 0) {
    print_stats();
  }
  std::exit(0);
  return 0;
}

void miner(const ton::Miner::Options& options) {
  auto res = ton::Miner::run(options);
  if (res) {
    found(res.value());
  }
}

class MinerBench : public td::Benchmark {
 public:
  std::string get_description() const override {
    return "Miner";
  }

  void run(int n) override {
    ton::Miner::Options options;
    options.my_address.parse_addr("EQDU86V5wyPrLd4nQ0RHPcCLPZq_y1O5wFWyTsMw63vjXTOv");
    std::fill(options.seed.begin(), options.seed.end(), 0xa7);
    std::fill(options.complexity.begin(), options.complexity.end(), 0);
    options.max_iterations = n;
    CHECK(!ton::Miner::run(options));
  }
};

int main(int argc, char* const argv[]) {
  ton::Miner::Options options;

  progname = argv[0];
  int i, threads = 0;
  bool bounce = false, benchmark = false;
  while ((i = getopt(argc, argv, "bnvw:t:Bh")) != -1) {
    switch (i) {
      case 'v':
        ++verbosity;
        break;
      case 'w':
        threads = atoi(optarg);
        CHECK(threads > 0 && threads <= 128);
        break;
      case 't': {
        int timeout = atoi(optarg);
        CHECK(timeout > 0);
        options.expire_at = td::Timestamp::in(timeout);
        break;
      }
      case 'B':
        benchmark = true;
        break;
      case 'b':
        bounce = true;
        break;
      case 'n':
        bounce = false;
        break;
      case 'h':
        return usage();
      default:
        std::cerr << "unknown option" << std::endl;
        return usage();
    }
  }
  if (benchmark && argc == optind) {
    td::bench(MinerBench());
    return 0;
  }

  if (argc != optind + 4 && argc != optind + 6) {
    return usage();
  }

  parse_addr(argv[optind], options.my_address);
  options.my_address.bounceable = bounce;
  CHECK(parse_bigint_chk(argv[optind + 1], 128)->export_bytes(options.seed.data(), 16, false));

  auto cmplx = parse_bigint_chk(argv[optind + 2], 256);
  CHECK(cmplx->export_bytes(options.complexity.data(), 32, false));
  CHECK(!cmplx->unsigned_fits_bits(256 - 62));
  td::BigInt256 bigpower, hrate;
  bigpower.set_pow2(256).mod_div(*cmplx, hrate);
  long long hash_rate = hrate.to_long();
  options.max_iterations = parse_bigint_chk(argv[optind + 3], 50)->to_long();
  if (argc == optind + 6) {
    make_boc = true;
    parse_addr(argv[optind + 4], miner_address);
    boc_filename = argv[optind + 5];
  }

  if (verbosity >= 2) {
    std::cerr << "[ expected required hashes for success: " << hash_rate << " ]" << std::endl;
  }
  if (benchmark) {
    td::bench(MinerBench());
  }

  start_at = td::Timestamp::now();

  options.hashes_computed = &hashes_computed;
  // may invoke several miner threads
  if (threads <= 0) {
    miner(options);
  } else {
    std::vector<std::thread> T;
    for (int i = 0; i < threads; i++) {
      T.emplace_back(miner, options);
    }
    for (auto& thr : T) {
      thr.join();
    }
  }
  if (verbosity > 0) {
    print_stats();
  }
}