// Copyright (c) 2014-2020, The Monero Project
//
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// permitted provided that the following conditions are met:
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// 2. Redistributions in binary form must reproduce the above copyright notice, this list
//    of conditions and the following disclaimer in the documentation and/or other
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// 3. Neither the name of the copyright holder nor the names of its contributors may be
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// 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
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// THE COPYRIGHT HOLDER 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
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// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers

#include "checkpoints.h"

#include "common/dns_utils.h"
#include "string_tools.h"
#include "storages/portable_storage_template_helper.h" // epee json include
#include "serialization/keyvalue_serialization.h"
#include <functional>
#include <vector>

using namespace epee;

#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "checkpoints"

namespace cryptonote
{
  /**
   * @brief struct for loading a checkpoint from json
   */
  struct t_hashline
  {
    uint64_t height; //!< the height of the checkpoint
    std::string hash; //!< the hash for the checkpoint
        BEGIN_KV_SERIALIZE_MAP()
          KV_SERIALIZE(height)
          KV_SERIALIZE(hash)
        END_KV_SERIALIZE_MAP()
  };

  /**
   * @brief struct for loading many checkpoints from json
   */
  struct t_hash_json {
    std::vector<t_hashline> hashlines; //!< the checkpoint lines from the file
        BEGIN_KV_SERIALIZE_MAP()
          KV_SERIALIZE(hashlines)
        END_KV_SERIALIZE_MAP()
  };

  //---------------------------------------------------------------------------
  checkpoints::checkpoints()
  {
  }
  //---------------------------------------------------------------------------
  bool checkpoints::add_checkpoint(uint64_t height, const std::string& hash_str, const std::string& difficulty_str)
  {
    crypto::hash h = crypto::null_hash;
    bool r = epee::string_tools::hex_to_pod(hash_str, h);
    CHECK_AND_ASSERT_MES(r, false, "Failed to parse checkpoint hash string into binary representation!");

    // return false if adding at a height we already have AND the hash is different
    if (m_points.count(height))
    {
      CHECK_AND_ASSERT_MES(h == m_points[height], false, "Checkpoint at given height already exists, and hash for new checkpoint was different!");
    }
    m_points[height] = h;
    if (!difficulty_str.empty())
    {
      try
      {
        difficulty_type difficulty(difficulty_str);
        if (m_difficulty_points.count(height))
        {
          CHECK_AND_ASSERT_MES(difficulty == m_difficulty_points[height], false, "Difficulty checkpoint at given height already exists, and difficulty for new checkpoint was different!");
        }
        m_difficulty_points[height] = difficulty;
      }
      catch (...)
      {
        LOG_ERROR("Failed to parse difficulty checkpoint: " << difficulty_str);
        return false;
      }
    }
    return true;
  }
  //---------------------------------------------------------------------------
  bool checkpoints::is_in_checkpoint_zone(uint64_t height) const
  {
    return !m_points.empty() && (height <= (--m_points.end())->first);
  }
  //---------------------------------------------------------------------------
  bool checkpoints::check_block(uint64_t height, const crypto::hash& h, bool& is_a_checkpoint) const
  {
    auto it = m_points.find(height);
    is_a_checkpoint = it != m_points.end();
    if(!is_a_checkpoint)
      return true;

    if(it->second == h)
    {
      MINFO("CHECKPOINT PASSED FOR HEIGHT " << height << " " << h);
      return true;
    }else
    {
      MWARNING("CHECKPOINT FAILED FOR HEIGHT " << height << ". EXPECTED HASH: " << it->second << ", FETCHED HASH: " << h);
      return false;
    }
  }
  //---------------------------------------------------------------------------
  bool checkpoints::check_block(uint64_t height, const crypto::hash& h) const
  {
    bool ignored;
    return check_block(height, h, ignored);
  }
  //---------------------------------------------------------------------------
  //FIXME: is this the desired behavior?
  bool checkpoints::is_alternative_block_allowed(uint64_t blockchain_height, uint64_t block_height) const
  {
    if (0 == block_height)
      return false;

    auto it = m_points.upper_bound(blockchain_height);
    // Is blockchain_height before the first checkpoint?
    if (it == m_points.begin())
      return true;

    --it;
    uint64_t checkpoint_height = it->first;
    return checkpoint_height < block_height;
  }
  //---------------------------------------------------------------------------
  uint64_t checkpoints::get_max_height() const
  {
    if (m_points.empty())
      return 0;
    return m_points.rbegin()->first;
  }
  //---------------------------------------------------------------------------
  const std::map<uint64_t, crypto::hash>& checkpoints::get_points() const
  {
    return m_points;
  }
  //---------------------------------------------------------------------------
  const std::map<uint64_t, difficulty_type>& checkpoints::get_difficulty_points() const
  {
    return m_difficulty_points;
  }

  bool checkpoints::check_for_conflicts(const checkpoints& other) const
  {
    for (auto& pt : other.get_points())
    {
      if (m_points.count(pt.first))
      {
        CHECK_AND_ASSERT_MES(pt.second == m_points.at(pt.first), false, "Checkpoint at given height already exists, and hash for new checkpoint was different!");
      }
    }
    return true;
  }

  bool checkpoints::init_default_checkpoints(network_type nettype)
  {
    if (nettype == TESTNET)
    {
    ADD_CHECKPOINT2(1,   "c47b8effcc84e22ddd1b876d059c8fbd3e26e4bdffb6bed8b8f4fe283104a7af", "0x2");
    ADD_CHECKPOINT2(5,   "292add330f6cf5f3845dc4cd2f28ce8d211dd487ddcfe1b5d1d545d7b90ff7d1", "0x5df");  //Hard fork to v8
    ADD_CHECKPOINT2(10,  "fbdf7d812aa6dd4c5915aadcbf023e722eab1d8ad47c24a230634e688d314798", "0xfa3");  //Hard fork to v9
    ADD_CHECKPOINT2(15,  "9b86e40b959d7cfe75366686dfd2657699e85b8c658aa8c20b23f7bc01b38af0", "0x1967"); //Hard fork to v10
    ADD_CHECKPOINT2(20,  "8f65c309ba3ed2bf25df2b7d91e1db40c864230aa3caaf823db81bc19e0bd6a3", "0x232b"); //Hard fork to v11
    ADD_CHECKPOINT2(25,  "35f2957fdba45d5421561ba2f126a61ec0101b5c2eb79b9e296310acbbdbbe58", "0x2cef"); //Hard fork to v12
    ADD_CHECKPOINT2(30,  "32cc5aacce8bea10ae869313e194ba51a30720810f3665433ffeea2818938429", "0x36b3"); //Hard fork to v13
    ADD_CHECKPOINT2(35,  "7f1cdd2c4a6002772343ad9de6c5dba743a0be1d326a6f63924511f08b15863a", "0x4077"); //Hard fork to v14
    ADD_CHECKPOINT2(40,  "63cf4f703489a881baf63bacd6a3af2b5bde79b558ce123e97313890be6f747f", "0x4a3b"); //Hard fork to v15
    ADD_CHECKPOINT2(45,  "65da4c966ae02983c6c8b7ab9b959df612863c379c5e48669061cbbb1e02a3ab", "0x53ff"); //Hard fork to v16
    ADD_CHECKPOINT2(50,  "8c68a444b6743a14152f130357be9751e42e82a84f69f25320eda532a830c7b0", "0x5dc3"); //Hard fork to v17
      return true;
    }
    if (nettype == STAGENET)
    {
      return true;
    }
    // make RPC call to daemon
    // curl http://127.0.0.1:34568/json_rpc -d '{"jsonrpc":"2.0","id":"0","method":"get_block","params":{"height":247600}}' -H 'Content-Type: application/json'
    // "wide_cumulative_difficulty": "0x14eb4d0131fe8",
    ADD_CHECKPOINT2(1,       "97f4ce4d7879b3bea54dcec738cd2ebb7952b4e9bb9743262310cd5fec749340", "0x2");
    ADD_CHECKPOINT2(6969,    "aa7b66e8c461065139b55c29538a39c33ceda93e587f84d490ed573d80511c87", "0x118eef693fd");  //Hard fork to v8
    ADD_CHECKPOINT2(53666,   "3f43f56f66ef0c43cf2fd14d0d28fa2aae0ef8f40716773511345750770f1255", "0xb677d6405ae");  //Hard fork to v9
    ADD_CHECKPOINT2(63469,   "4e33a9343fc5b86661ec0affaeb5b5a065290602c02d817337e4a979fe5747d8", "0xe7cd9819062");  //Hard fork to v10
    ADD_CHECKPOINT2(81769,   "41db9fef8d0ccfa78b570ee9525d4f55de77b510c3ae4b08a1d51b9aec9ade1d", "0x150066455b88"); //Hard fork to v11
    ADD_CHECKPOINT2(82069,   "fdea800d23d0b2eea19dec8af31e453e883e8315c97e25c8bb3e88ca164f8369", "0x15079b5fdaa8"); //Hard fork to v12
    ADD_CHECKPOINT2(114969,  "b48245956b87f243048fd61021f4b3e5443e57eee7ff8ba4762d18926e80b80c", "0x1ca552b3ec68"); //Hard fork to v13
    ADD_CHECKPOINT2(115257,  "338e056551087fe23d6c4b4280244bc5362b004716d85ec799a775f190f9fea9", "0x1cb25f5d4628"); //Hard fork to v14
    ADD_CHECKPOINT2(160777,  "9496690579af21f38f00e67e11c2e85a15912fe4f412aad33d1162be1579e755", "0x5376eaa196a8"); //Hard fork to v15
    ADD_CHECKPOINT2(247600,  "f5ecf7b9d2376d7b1d4ca7843c7d39c5854b8f94c968bf9bc2072fa2e0c92ef7", "0x14eb4d0131fe8");
    ADD_CHECKPOINT2(251200,  "e2df45d2d9a176417a0731215420e775b4f445d888c8ec4d6bbeaabead751f52", "0x163e0e5f70068");

    return true;
  }

  bool checkpoints::load_checkpoints_from_json(const std::string &json_hashfile_fullpath)
  {
    boost::system::error_code errcode;
    if (! (boost::filesystem::exists(json_hashfile_fullpath, errcode)))
    {
      LOG_PRINT_L1("Blockchain checkpoints file not found");
      return true;
    }

    LOG_PRINT_L1("Adding checkpoints from blockchain hashfile");

    uint64_t prev_max_height = get_max_height();
    LOG_PRINT_L1("Hard-coded max checkpoint height is " << prev_max_height);
    t_hash_json hashes;
    if (!epee::serialization::load_t_from_json_file(hashes, json_hashfile_fullpath))
    {
      MERROR("Error loading checkpoints from " << json_hashfile_fullpath);
      return false;
    }
    for (std::vector<t_hashline>::const_iterator it = hashes.hashlines.begin(); it != hashes.hashlines.end(); )
    {
      uint64_t height;
      height = it->height;
      if (height <= prev_max_height) {
	LOG_PRINT_L1("ignoring checkpoint height " << height);
      } else {
	std::string blockhash = it->hash;
	LOG_PRINT_L1("Adding checkpoint height " << height << ", hash=" << blockhash);
	ADD_CHECKPOINT(height, blockhash);
      }
      ++it;
    }

    return true;
  }

  bool checkpoints::load_checkpoints_from_dns(network_type nettype)
  {
    std::vector<std::string> records;

    // All four MoneroPulse domains have DNSSEC on and valid
    static const std::vector<std::string> dns_urls = { 
    };

    static const std::vector<std::string> testnet_dns_urls = { 
    };

    static const std::vector<std::string> stagenet_dns_urls = { 
    };

    if (!tools::dns_utils::load_txt_records_from_dns(records, nettype == TESTNET ? testnet_dns_urls : nettype == STAGENET ? stagenet_dns_urls : dns_urls))
      return true; // why true ?

    for (const auto& record : records)
    {
      auto pos = record.find(":");
      if (pos != std::string::npos)
      {
        uint64_t height;
        crypto::hash hash;

        // parse the first part as uint64_t,
        // if this fails move on to the next record
        std::stringstream ss(record.substr(0, pos));
        if (!(ss >> height))
        {
    continue;
        }

        // parse the second part as crypto::hash,
        // if this fails move on to the next record
        std::string hashStr = record.substr(pos + 1);
        if (!epee::string_tools::hex_to_pod(hashStr, hash))
        {
    continue;
        }

        ADD_CHECKPOINT(height, hashStr);
      }
    }
    return true;
  }

  bool checkpoints::load_new_checkpoints(const std::string &json_hashfile_fullpath, network_type nettype, bool dns)
  {
    bool result;

    result = load_checkpoints_from_json(json_hashfile_fullpath);
    if (dns)
    {
      result &= load_checkpoints_from_dns(nettype);
    }

    return result;
  }
}