/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "hci/address.h"

#include <packet_runtime.h>

#include <algorithm>
#include <array>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iterator>
#include <optional>
#include <sstream>
#include <string>
#include <utility>

namespace bluetooth::hci {

const Address Address::kAny{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
const Address Address::kEmpty{0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

// Address cannot initialize member variables as it is a POD type
// NOLINTNEXTLINE(cppcoreguidelines-pro-type-member-init)
constexpr Address::Address(std::array<uint8_t, kLength> const& address) : address(address) {}

Address::Address(const uint8_t (&address)[kLength]) {
  std::copy(address, address + kLength, this->address.begin());
}

Address::Address(std::initializer_list<uint8_t> l) {
  std::copy(l.begin(), std::min(l.begin() + kLength, l.end()), data());
}

bool Address::Parse(pdl::packet::slice& input, Address* output) {
  if (input.size() < kLength) {
    return false;
  }

  std::array<uint8_t, kLength> address{
          input.read_le<uint8_t>(), input.read_le<uint8_t>(), input.read_le<uint8_t>(),
          input.read_le<uint8_t>(), input.read_le<uint8_t>(), input.read_le<uint8_t>(),
  };
  *output = Address(address);
  return true;
}

std::string Address::ToString() const {
  std::stringstream ss;
  for (auto it = address.rbegin(); it != address.rend(); it++) {
    ss << std::nouppercase << std::hex << std::setw(2) << std::setfill('0') << +*it;
    if (std::next(it) != address.rend()) {
      ss << ':';
    }
  }
  return ss.str();
}

std::optional<Address> Address::FromString(const std::string& from) {
  if (from.length() != 17) {
    return std::nullopt;
  }

  Address addr{};
  std::istringstream stream(from);
  std::string token;
  int index = 0;
  while (getline(stream, token, ':')) {
    if (index >= 6) {
      return std::nullopt;
    }

    if (token.length() != 2) {
      return std::nullopt;
    }

    char* temp = nullptr;
    addr.address.at(5 - index) = std::strtol(token.c_str(), &temp, 16);
    if (temp == token.c_str()) {
      // string token is empty or has wrong format
      return std::nullopt;
    }
    if (temp != (token.c_str() + token.size())) {
      // cannot parse whole string
      return std::nullopt;
    }

    index++;
  }

  if (index != 6) {
    return std::nullopt;
  }

  return addr;
}

bool Address::FromString(const std::string& from, Address& to) {
  auto addr = FromString(from);
  if (!addr) {
    to = {};
    return false;
  }
  to = std::move(*addr);
  return true;
}

size_t Address::FromOctets(const uint8_t* from) {
  std::copy(from, from + kLength, data());
  return kLength;
}

bool Address::IsValidAddress(const std::string& address) {
  return Address::FromString(address).has_value();
}

}  // namespace bluetooth::hci