#include "c.h"

#include <rocksdb/db.h>
#include <rocksdb/utilities/checkpoint.h>
#include <rocksdb/utilities/transaction_db.h>

#include <vector>

using ROCKSDB_NAMESPACE::Checkpoint;
using ROCKSDB_NAMESPACE::ColumnFamilyDescriptor;
using ROCKSDB_NAMESPACE::ColumnFamilyHandle;
using ROCKSDB_NAMESPACE::ColumnFamilyOptions;
using ROCKSDB_NAMESPACE::CompactRangeOptions;
using ROCKSDB_NAMESPACE::DB;
using ROCKSDB_NAMESPACE::DBOptions;
using ROCKSDB_NAMESPACE::FlushOptions;
using ROCKSDB_NAMESPACE::IngestExternalFileOptions;
using ROCKSDB_NAMESPACE::Iterator;
using ROCKSDB_NAMESPACE::Options;
using ROCKSDB_NAMESPACE::PinnableSlice;
using ROCKSDB_NAMESPACE::ReadOptions;
using ROCKSDB_NAMESPACE::Slice;
using ROCKSDB_NAMESPACE::SstFileWriter;
using ROCKSDB_NAMESPACE::Status;
using ROCKSDB_NAMESPACE::Transaction;
using ROCKSDB_NAMESPACE::TransactionDB;
using ROCKSDB_NAMESPACE::TransactionDBOptions;
using ROCKSDB_NAMESPACE::WriteOptions;
using std::vector;

// From RocksDB
extern "C" {
struct rocksdb_t {
  DB* rep;
};

struct rocksdb_column_family_handle_t {
  ColumnFamilyHandle* rep;
};

struct rocksdb_compactoptions_t {
  CompactRangeOptions rep;
  Slice full_history_ts_low;
};

struct rocksdb_flushoptions_t {
  FlushOptions rep;
};

struct rocksdb_ingestexternalfileoptions_t {
  IngestExternalFileOptions rep;
};

struct rocksdb_iterator_t {
  Iterator* rep;
};

struct rocksdb_options_t {
  Options rep;
};

struct rocksdb_pinnableslice_t {
  PinnableSlice rep;
};

struct rocksdb_readoptions_t {
  ReadOptions rep;
  // stack variables to set pointers to in ReadOptions
  Slice upper_bound;
  Slice lower_bound;
  Slice timestamp;
  Slice iter_start_ts;
};

struct rocksdb_sstfilewriter_t {
  SstFileWriter* rep;
};

struct rocksdb_transaction_t {
  Transaction* rep;
};

struct rocksdb_transactiondb_t {
  TransactionDB* rep;
};

struct rocksdb_transactiondb_options_t {
  TransactionDBOptions rep;
};

struct rocksdb_writeoptions_t {
  WriteOptions rep;
};
}

static bool SaveStatus(rocksdb_status_t* target, const Status source) {
  target->code = static_cast<rocksdb_status_code_t>(source.code());
  target->subcode = static_cast<rocksdb_status_subcode_t>(source.subcode());
  target->severity = static_cast<rocksdb_status_severity_t>(source.severity());
  if (source.ok()) {
    target->string = nullptr;
  } else {
    std::string msg = source.ToString();
    char* string = new char[msg.size() + 1];  // we need extra char for NUL
    memcpy(string, msg.c_str(), msg.size() + 1);
    target->string = string;
  }
  return !source.ok();
}

extern "C" {

rocksdb_pinnableslice_t* rocksdb_get_pinned_cf_with_status(
    rocksdb_t* db, const rocksdb_readoptions_t* options,
    rocksdb_column_family_handle_t* column_family, const char* key,
    size_t keylen, rocksdb_status_t* statusptr) {
  rocksdb_pinnableslice_t* v = new (rocksdb_pinnableslice_t);
  Status s = db->rep->Get(options->rep, column_family->rep, Slice(key, keylen),
                          &v->rep);
  if (!s.ok()) {
    delete v;
    if (!s.IsNotFound()) {
      SaveStatus(statusptr, s);
    }
    return nullptr;
  }
  return v;
}

rocksdb_t* rocksdb_open_for_read_only_column_families_with_status(
    const rocksdb_options_t* db_options, const char* name,
    int num_column_families, const char* const* column_family_names,
    const rocksdb_options_t* const* column_family_options,
    rocksdb_column_family_handle_t** column_family_handles,
    unsigned char error_if_wal_file_exists, rocksdb_status_t* statusptr) {
  vector<ColumnFamilyDescriptor> column_families;
  for (int i = 0; i < num_column_families; i++) {
    column_families.emplace_back(ColumnFamilyDescriptor(
        std::string(column_family_names[i]),
        ColumnFamilyOptions(column_family_options[i]->rep)));
  }

  DB* db;
  vector<ColumnFamilyHandle*> handles;
  if (SaveStatus(statusptr, DB::OpenForReadOnly(DBOptions(db_options->rep),
                                                std::string(name),
                                                column_families, &handles, &db,
                                                error_if_wal_file_exists))) {
    return nullptr;
  }

  for (size_t i = 0; i < handles.size(); i++) {
    rocksdb_column_family_handle_t* c_handle =
        new rocksdb_column_family_handle_t;
    c_handle->rep = handles[i];
    column_family_handles[i] = c_handle;
  }
  rocksdb_t* result = new rocksdb_t;
  result->rep = db;
  return result;
}

void rocksdb_try_catch_up_with_primary_with_status(
    rocksdb_t* db, rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, db->rep->TryCatchUpWithPrimary());
}

rocksdb_t* rocksdb_open_as_secondary_column_families_with_status(
    const rocksdb_options_t* db_options, const char* name,
    const char* secondary_path, int num_column_families,
    const char* const* column_family_names,
    const rocksdb_options_t* const* column_family_options,
    rocksdb_column_family_handle_t** column_family_handles,
    rocksdb_status_t* statusptr) {
  vector<ColumnFamilyDescriptor> column_families;
  for (int i = 0; i != num_column_families; ++i) {
    column_families.emplace_back(
        std::string(column_family_names[i]),
        ColumnFamilyOptions(column_family_options[i]->rep));
  }
  DB* db;
  vector<ColumnFamilyHandle*> handles;
  if (SaveStatus(statusptr, DB::OpenAsSecondary(
                                DBOptions(db_options->rep), std::string(name),
                                std::string(secondary_path), column_families,
                                &handles, &db))) {
    return nullptr;
  }
  for (size_t i = 0; i != handles.size(); ++i) {
    rocksdb_column_family_handle_t* c_handle =
        new rocksdb_column_family_handle_t;
    c_handle->rep = handles[i];
    column_family_handles[i] = c_handle;
  }
  rocksdb_t* result = new rocksdb_t;
  result->rep = db;
  return result;
}

void rocksdb_create_checkpoint_with_status(rocksdb_t* db,
                                           const char* checkpoint_dir,
                                           rocksdb_status_t* statusptr) {
  Checkpoint* checkpoint;
  Status s = Checkpoint::Create(db->rep, &checkpoint);
  if (!s.ok()) {
    SaveStatus(statusptr, s);
    return;
  }
  SaveStatus(statusptr,
             checkpoint->CreateCheckpoint(std::string(checkpoint_dir)));
  delete checkpoint;
}

rocksdb_transactiondb_t* rocksdb_transactiondb_open_column_families_with_status(
    const rocksdb_options_t* options,
    const rocksdb_transactiondb_options_t* txn_db_options, const char* name,
    int num_column_families, const char* const* column_family_names,
    const rocksdb_options_t* const* column_family_options,
    rocksdb_column_family_handle_t** column_family_handles,
    rocksdb_status_t* statusptr) {
  vector<ColumnFamilyDescriptor> column_families;
  for (int i = 0; i < num_column_families; i++) {
    column_families.emplace_back(ColumnFamilyDescriptor(
        std::string(column_family_names[i]),
        ColumnFamilyOptions(column_family_options[i]->rep)));
  }

  TransactionDB* txn_db;
  vector<ColumnFamilyHandle*> handles;
  if (SaveStatus(statusptr,
                 TransactionDB::Open(options->rep, txn_db_options->rep,
                                     std::string(name), column_families,
                                     &handles, &txn_db))) {
    return nullptr;
  }

  for (size_t i = 0; i < handles.size(); i++) {
    rocksdb_column_family_handle_t* c_handle =
        new rocksdb_column_family_handle_t;
    c_handle->rep = handles[i];
    column_family_handles[i] = c_handle;
  }
  rocksdb_transactiondb_t* result = new rocksdb_transactiondb_t;
  result->rep = txn_db;
  return result;
}

rocksdb_pinnableslice_t* rocksdb_transactiondb_get_pinned_cf_with_status(
    rocksdb_transactiondb_t* db, const rocksdb_readoptions_t* options,
    rocksdb_column_family_handle_t* column_family, const char* key,
    size_t keylen, rocksdb_status_t* statusptr) {
  rocksdb_pinnableslice_t* v = new rocksdb_pinnableslice_t;
  Status s = db->rep->Get(options->rep, column_family->rep, Slice(key, keylen),
                          &v->rep);
  if (!s.ok()) {
    delete v;
    if (!s.IsNotFound()) {
      SaveStatus(statusptr, s);
    }
    return nullptr;
  }
  return v;
}

void rocksdb_transactiondb_put_cf_with_status(
    rocksdb_transactiondb_t* txn_db, const rocksdb_writeoptions_t* options,
    rocksdb_column_family_handle_t* column_family, const char* key,
    size_t keylen, const char* val, size_t vallen,
    rocksdb_status_t* statusptr) {
  SaveStatus(statusptr,
             txn_db->rep->Put(options->rep, column_family->rep,
                              Slice(key, keylen), Slice(val, vallen)));
}

void rocksdb_transactiondb_flush_cfs_with_status(
    rocksdb_transactiondb_t* db, const rocksdb_flushoptions_t* options,
    rocksdb_column_family_handle_t** column_families, int num_column_families,
    rocksdb_status_t* statusptr) {
  vector<ColumnFamilyHandle*> column_family_handles(num_column_families);
  for (int i = 0; i < num_column_families; i++) {
    column_family_handles[i] = column_families[i]->rep;
  }
  SaveStatus(statusptr, db->rep->Flush(options->rep, column_family_handles));
}

void rocksdb_transactiondb_compact_range_cf_opt_with_status(
    rocksdb_transactiondb_t* db, rocksdb_column_family_handle_t* column_family,
    rocksdb_compactoptions_t* opt, const char* start_key, size_t start_key_len,
    const char* limit_key, size_t limit_key_len, rocksdb_status_t* statusptr) {
  Slice a, b;
  SaveStatus(
      statusptr,
      db->rep->CompactRange(
          opt->rep, column_family->rep,
          // Pass nullptr Slice if corresponding "const char*" is nullptr
          (start_key ? (a = Slice(start_key, start_key_len), &a) : nullptr),
          (limit_key ? (b = Slice(limit_key, limit_key_len), &b) : nullptr)));
}

void rocksdb_transactiondb_ingest_external_files_with_status(
    rocksdb_transactiondb_t* db, const rocksdb_ingestexternalfilearg_t* list,
    const size_t list_len, rocksdb_status_t* statusptr) {
  vector<rocksdb::IngestExternalFileArg> args(list_len);
  for (size_t i = 0; i < list_len; ++i) {
    args[i].column_family = list[i].column_family->rep;
    vector<std::string> files(list[i].external_files_len);
    for (size_t j = 0; j < list[i].external_files_len; ++j) {
      files[j] = std::string(list[i].external_files[j]);
    }
    args[i].external_files = files;
    args[i].options = list[i].options->rep;
  }
  SaveStatus(statusptr, db->rep->IngestExternalFiles(args));
}

void rocksdb_transactiondb_create_checkpoint_with_status(
    rocksdb_transactiondb_t* db, const char* checkpoint_dir,
    rocksdb_status_t* statusptr) {
  Checkpoint* checkpoint;
  Status s = Checkpoint::Create(db->rep, &checkpoint);
  if (!s.ok()) {
    SaveStatus(statusptr, s);
    return;
  }
  SaveStatus(statusptr,
             checkpoint->CreateCheckpoint(std::string(checkpoint_dir)));
  delete checkpoint;
}

void rocksdb_transaction_commit_with_status(rocksdb_transaction_t* txn,
                                            rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, txn->rep->Commit());
}

void rocksdb_transaction_rollback_with_status(rocksdb_transaction_t* txn,
                                              rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, txn->rep->Rollback());
}

rocksdb_pinnableslice_t* rocksdb_transaction_get_pinned_cf_with_status(
    rocksdb_transaction_t* txn, const rocksdb_readoptions_t* options,
    rocksdb_column_family_handle_t* column_family, const char* key,
    size_t keylen, rocksdb_status_t* statusptr) {
  rocksdb_pinnableslice_t* v = new rocksdb_pinnableslice_t;
  Status s = txn->rep->Get(options->rep, column_family->rep, Slice(key, keylen),
                           &v->rep);
  if (!s.ok()) {
    delete v;
    if (!s.IsNotFound()) {
      SaveStatus(statusptr, s);
    }
    return nullptr;
  }
  return v;
}

rocksdb_pinnableslice_t*
rocksdb_transaction_get_for_update_pinned_cf_with_status(
    rocksdb_transaction_t* txn, const rocksdb_readoptions_t* options,
    rocksdb_column_family_handle_t* column_family, const char* key,
    size_t keylen, rocksdb_status_t* statusptr) {
  rocksdb_pinnableslice_t* v = new rocksdb_pinnableslice_t;
  Status s = txn->rep->GetForUpdate(options->rep, column_family->rep,
                                    Slice(key, keylen), &v->rep);
  if (!s.ok()) {
    delete v;
    if (!s.IsNotFound()) {
      SaveStatus(statusptr, s);
    }
    return nullptr;
  }
  return v;
}

void rocksdb_transaction_put_cf_with_status(
    rocksdb_transaction_t* txn, rocksdb_column_family_handle_t* column_family,
    const char* key, size_t klen, const char* val, size_t vlen,
    rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, txn->rep->Put(column_family->rep, Slice(key, klen),
                                      Slice(val, vlen)));
}

void rocksdb_transaction_delete_cf_with_status(
    rocksdb_transaction_t* txn, rocksdb_column_family_handle_t* column_family,
    const char* key, size_t klen, rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, txn->rep->Delete(column_family->rep, Slice(key, klen)));
}

void rocksdb_sstfilewriter_open_with_status(rocksdb_sstfilewriter_t* writer,
                                            const char* name,
                                            rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, writer->rep->Open(std::string(name)));
}

void rocksdb_sstfilewriter_put_with_status(rocksdb_sstfilewriter_t* writer,
                                           const char* key, size_t keylen,
                                           const char* val, size_t vallen,
                                           rocksdb_status_t* statusptr) {
  SaveStatus(statusptr,
             writer->rep->Put(Slice(key, keylen), Slice(val, vallen)));
}

void rocksdb_sstfilewriter_finish_with_status(rocksdb_sstfilewriter_t* writer,
                                              rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, writer->rep->Finish(nullptr));
}

void rocksdb_iter_get_status(const rocksdb_iterator_t* iter,
                             rocksdb_status_t* statusptr) {
  SaveStatus(statusptr, iter->rep->status());
}

rocksdb_readoptions_t* rocksdb_readoptions_create_copy(
    rocksdb_readoptions_t* options) {
  return new rocksdb_readoptions_t(*options);
}
}