//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
//  This source code is licensed under the BSD-style license found in the
//  LICENSE file in the root directory of this source tree. An additional grant
//  of patent rights can be found in the PATENTS file in the same directory.

#include <map>
#include <memory>
#include <string>
#include <vector>

#include "db/db_impl.h"
#include "db/dbformat.h"
#include "db/table_properties_collector.h"
#include "rocksdb/table.h"
#include "rocksdb/immutable_options.h"
#include "table/block_based_table_factory.h"
#include "table/meta_blocks.h"
#include "table/plain_table_factory.h"
#include "table/table_builder.h"
#include "util/coding.h"
#include "util/testharness.h"
#include "util/testutil.h"

namespace rocksdb {

class TablePropertiesTest : public testing::Test,
                            public testing::WithParamInterface<bool> {
 public:
  virtual void SetUp() override { backward_mode_ = GetParam(); }

  bool backward_mode_;
};

// TODO(kailiu) the following classes should be moved to some more general
// places, so that other tests can also make use of them.
// `FakeWritableFile` and `FakeRandomeAccessFile` bypass the real file system
// and therefore enable us to quickly setup the tests.
class FakeWritableFile : public WritableFile {
 public:
  ~FakeWritableFile() { }

  const std::string& contents() const { return contents_; }

  virtual Status Close() override { return Status::OK(); }
  virtual Status Flush() override { return Status::OK(); }
  virtual Status Sync() override { return Status::OK(); }

  virtual Status Append(const Slice& data) override {
    contents_.append(data.data(), data.size());
    return Status::OK();
  }

 private:
  std::string contents_;
};


class FakeRandomeAccessFile : public RandomAccessFile {
 public:
  explicit FakeRandomeAccessFile(const Slice& contents)
      : contents_(contents.data(), contents.size()) {
  }

  virtual ~FakeRandomeAccessFile() { }

  uint64_t Size() const { return contents_.size(); }

  virtual Status Read(uint64_t offset, size_t n, Slice* result,
                      char* scratch) const override {
    if (offset > contents_.size()) {
      return Status::InvalidArgument("invalid Read offset");
    }
    if (offset + n > contents_.size()) {
      n = contents_.size() - offset;
    }
    memcpy(scratch, &contents_[offset], n);
    *result = Slice(scratch, n);
    return Status::OK();
  }

 private:
  std::string contents_;
};


class DumbLogger : public Logger {
 public:
  using Logger::Logv;
  virtual void Logv(const char* format, va_list ap) override {}
  virtual size_t GetLogFileSize() const override { return 0; }
};

// Utilities test functions
namespace {
void MakeBuilder(const Options& options, const ImmutableCFOptions& ioptions,
                 const InternalKeyComparator& internal_comparator,
                 const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
                     int_tbl_prop_collector_factories,
                 std::unique_ptr<FakeWritableFile>* writable,
                 std::unique_ptr<TableBuilder>* builder) {
  writable->reset(new FakeWritableFile);
  builder->reset(NewTableBuilder(
      ioptions, internal_comparator, int_tbl_prop_collector_factories,
      writable->get(), options.compression, options.compression_opts));
}
}  // namespace

// Collects keys that starts with "A" in a table.
class RegularKeysStartWithA: public TablePropertiesCollector {
 public:
  const char* Name() const override { return "RegularKeysStartWithA"; }

  Status Finish(UserCollectedProperties* properties) override {
     std::string encoded;
     std::string encoded_num_puts;
     std::string encoded_num_deletes;
     std::string encoded_num_size_changes;
     PutVarint32(&encoded, count_);
     PutVarint32(&encoded_num_puts, num_puts_);
     PutVarint32(&encoded_num_deletes, num_deletes_);
     PutVarint32(&encoded_num_size_changes, num_size_changes_);
     *properties = UserCollectedProperties{
         {"TablePropertiesTest", message_},
         {"Count", encoded},
         {"NumPuts", encoded_num_puts},
         {"NumDeletes", encoded_num_deletes},
         {"NumSizeChanges", encoded_num_size_changes},
     };
     return Status::OK();
  }

  Status AddUserKey(const Slice& user_key, const Slice& value, EntryType type,
                    SequenceNumber seq, uint64_t file_size) override {
    // simply asssume all user keys are not empty.
    if (user_key.data()[0] == 'A') {
      ++count_;
    }
    if (type == kEntryPut) {
      num_puts_++;
    } else if (type == kEntryDelete) {
      num_deletes_++;
    }
    if (file_size < file_size_) {
      message_ = "File size should not decrease.";
    } else if (file_size != file_size_) {
      num_size_changes_++;
    }

    return Status::OK();
  }

  virtual UserCollectedProperties GetReadableProperties() const override {
    return UserCollectedProperties{};
  }

 private:
  std::string message_ = "Rocksdb";
  uint32_t count_ = 0;
  uint32_t num_puts_ = 0;
  uint32_t num_deletes_ = 0;
  uint32_t num_size_changes_ = 0;
  uint64_t file_size_ = 0;
};

// Collects keys that starts with "A" in a table. Backward compatible mode
// It is also used to test internal key table property collector
class RegularKeysStartWithABackwardCompatible
    : public TablePropertiesCollector {
 public:
  const char* Name() const override { return "RegularKeysStartWithA"; }

  Status Finish(UserCollectedProperties* properties) override {
    std::string encoded;
    PutVarint32(&encoded, count_);
    *properties = UserCollectedProperties{{"TablePropertiesTest", "Rocksdb"},
                                          {"Count", encoded}};
    return Status::OK();
  }

  Status Add(const Slice& user_key, const Slice& value) override {
    // simply asssume all user keys are not empty.
    if (user_key.data()[0] == 'A') {
      ++count_;
    }
    return Status::OK();
  }

  virtual UserCollectedProperties GetReadableProperties() const override {
    return UserCollectedProperties{};
  }

 private:
  uint32_t count_ = 0;
};

class RegularKeysStartWithAInternal : public IntTblPropCollector {
 public:
  const char* Name() const override { return "RegularKeysStartWithA"; }

  Status Finish(UserCollectedProperties* properties) override {
    std::string encoded;
    PutVarint32(&encoded, count_);
    *properties = UserCollectedProperties{{"TablePropertiesTest", "Rocksdb"},
                                          {"Count", encoded}};
    return Status::OK();
  }

  Status InternalAdd(const Slice& user_key, const Slice& value,
                     uint64_t file_size) override {
    // simply asssume all user keys are not empty.
    if (user_key.data()[0] == 'A') {
      ++count_;
    }
    return Status::OK();
  }

  virtual UserCollectedProperties GetReadableProperties() const override {
    return UserCollectedProperties{};
  }

 private:
  uint32_t count_ = 0;
};

class RegularKeysStartWithAFactory : public IntTblPropCollectorFactory,
                                     public TablePropertiesCollectorFactory {
 public:
  explicit RegularKeysStartWithAFactory(bool backward_mode)
      : backward_mode_(backward_mode) {}
  virtual TablePropertiesCollector* CreateTablePropertiesCollector() override {
    if (!backward_mode_) {
      return new RegularKeysStartWithA();
    } else {
      return new RegularKeysStartWithABackwardCompatible();
    }
  }
  virtual IntTblPropCollector* CreateIntTblPropCollector() override {
    return new RegularKeysStartWithAInternal();
  }
  const char* Name() const override { return "RegularKeysStartWithA"; }

  bool backward_mode_;
};

class FlushBlockEveryThreePolicy : public FlushBlockPolicy {
 public:
  virtual bool Update(const Slice& key, const Slice& value) override {
    return (++count_ % 3U == 0);
  }

 private:
  uint64_t count_ = 0;
};

class FlushBlockEveryThreePolicyFactory : public FlushBlockPolicyFactory {
 public:
  explicit FlushBlockEveryThreePolicyFactory() {}

  const char* Name() const override {
    return "FlushBlockEveryThreePolicyFactory";
  }

  FlushBlockPolicy* NewFlushBlockPolicy(
      const BlockBasedTableOptions& table_options,
      const BlockBuilder& data_block_builder) const override {
    return new FlushBlockEveryThreePolicy;
  }
};

extern uint64_t kBlockBasedTableMagicNumber;
extern uint64_t kPlainTableMagicNumber;
namespace {
void TestCustomizedTablePropertiesCollector(
    bool backward_mode, uint64_t magic_number, bool test_int_tbl_prop_collector,
    const Options& options, const InternalKeyComparator& internal_comparator) {
  const std::string kDeleteFlag = "D";
  // make sure the entries will be inserted with order.
  std::map<std::string, std::string> kvs = {
      {"About   ", "val5"},  // starts with 'A'
      {"Abstract", "val2"},  // starts with 'A'
      {"Around  ", "val7"},  // starts with 'A'
      {"Beyond  ", "val3"},
      {"Builder ", "val1"},
      {"Love    ", kDeleteFlag},
      {"Cancel  ", "val4"},
      {"Find    ", "val6"},
      {"Rocks   ", kDeleteFlag},
  };

  // -- Step 1: build table
  std::unique_ptr<TableBuilder> builder;
  std::unique_ptr<FakeWritableFile> writable;
  const ImmutableCFOptions ioptions(options);
  std::vector<std::unique_ptr<IntTblPropCollectorFactory>>
      int_tbl_prop_collector_factories;
  if (test_int_tbl_prop_collector) {
    int_tbl_prop_collector_factories.emplace_back(
        new RegularKeysStartWithAFactory(backward_mode));
  } else {
    GetIntTblPropCollectorFactory(options, &int_tbl_prop_collector_factories);
  }
  MakeBuilder(options, ioptions, internal_comparator,
              &int_tbl_prop_collector_factories, &writable, &builder);

  SequenceNumber seqNum = 0U;
  for (const auto& kv : kvs) {
    InternalKey ikey(kv.first, seqNum++, (kv.second != kDeleteFlag)
                                             ? ValueType::kTypeValue
                                             : ValueType::kTypeDeletion);
    builder->Add(ikey.Encode(), kv.second);
  }
  ASSERT_OK(builder->Finish());

  // -- Step 2: Read properties
  FakeRandomeAccessFile readable(writable->contents());
  TableProperties* props;
  Status s = ReadTableProperties(
      &readable,
      writable->contents().size(),
      magic_number,
      Env::Default(),
      nullptr,
      &props
  );
  std::unique_ptr<TableProperties> props_guard(props);
  ASSERT_OK(s);

  auto user_collected = props->user_collected_properties;

  ASSERT_TRUE(user_collected.find("TablePropertiesTest") !=
              user_collected.end());
  ASSERT_EQ("Rocksdb", user_collected.at("TablePropertiesTest"));

  uint32_t starts_with_A = 0;
  ASSERT_TRUE(user_collected.find("Count") != user_collected.end());
  Slice key(user_collected.at("Count"));
  ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
  ASSERT_EQ(3u, starts_with_A);

  if (!backward_mode && !test_int_tbl_prop_collector) {
    uint32_t num_deletes;
    ASSERT_TRUE(user_collected.find("NumDeletes") != user_collected.end());
    Slice key_deletes(user_collected.at("NumDeletes"));
    ASSERT_TRUE(GetVarint32(&key_deletes, &num_deletes));
    ASSERT_EQ(2u, num_deletes);

    uint32_t num_puts;
    ASSERT_TRUE(user_collected.find("NumPuts") != user_collected.end());
    Slice key_puts(user_collected.at("NumPuts"));
    ASSERT_TRUE(GetVarint32(&key_puts, &num_puts));
    ASSERT_EQ(7u, num_puts);

    uint32_t num_size_changes;
    ASSERT_TRUE(user_collected.find("NumSizeChanges") != user_collected.end());
    Slice key_size_changes(user_collected.at("NumSizeChanges"));
    ASSERT_TRUE(GetVarint32(&key_size_changes, &num_size_changes));
    ASSERT_GE(num_size_changes, 2u);
  }
}
}  // namespace

TEST_P(TablePropertiesTest, CustomizedTablePropertiesCollector) {
  // Test properties collectors with internal keys or regular keys
  // for block based table
  for (bool encode_as_internal : { true, false }) {
    if (!backward_mode_ && !encode_as_internal) {
      continue;
    }

    Options options;
    BlockBasedTableOptions table_options;
    table_options.flush_block_policy_factory =
        std::make_shared<FlushBlockEveryThreePolicyFactory>();
    options.table_factory.reset(NewBlockBasedTableFactory(table_options));

    test::PlainInternalKeyComparator ikc(options.comparator);
    std::shared_ptr<TablePropertiesCollectorFactory> collector_factory(
        new RegularKeysStartWithAFactory(backward_mode_));
    options.table_properties_collector_factories.resize(1);
    options.table_properties_collector_factories[0] = collector_factory;

    TestCustomizedTablePropertiesCollector(backward_mode_,
                                           kBlockBasedTableMagicNumber,
                                           encode_as_internal, options, ikc);

    // test plain table
    PlainTableOptions plain_table_options;
    plain_table_options.user_key_len = 8;
    plain_table_options.bloom_bits_per_key = 8;
    plain_table_options.hash_table_ratio = 0;

    options.table_factory =
        std::make_shared<PlainTableFactory>(plain_table_options);
    TestCustomizedTablePropertiesCollector(backward_mode_,
                                           kPlainTableMagicNumber,
                                           encode_as_internal, options, ikc);
  }
}

namespace {
void TestInternalKeyPropertiesCollector(
    bool backward_mode, uint64_t magic_number, bool sanitized,
    std::shared_ptr<TableFactory> table_factory) {
  InternalKey keys[] = {
      InternalKey("A       ", 0, ValueType::kTypeValue),
      InternalKey("B       ", 1, ValueType::kTypeValue),
      InternalKey("C       ", 2, ValueType::kTypeValue),
      InternalKey("W       ", 3, ValueType::kTypeDeletion),
      InternalKey("X       ", 4, ValueType::kTypeDeletion),
      InternalKey("Y       ", 5, ValueType::kTypeDeletion),
      InternalKey("Z       ", 6, ValueType::kTypeDeletion),
  };

  std::unique_ptr<TableBuilder> builder;
  std::unique_ptr<FakeWritableFile> writable;
  Options options;
  test::PlainInternalKeyComparator pikc(options.comparator);

  std::vector<std::unique_ptr<IntTblPropCollectorFactory>>
      int_tbl_prop_collector_factories;
  options.table_factory = table_factory;
  if (sanitized) {
    options.table_properties_collector_factories.emplace_back(
        new RegularKeysStartWithAFactory(backward_mode));
    // with sanitization, even regular properties collector will be able to
    // handle internal keys.
    auto comparator = options.comparator;
    // HACK: Set options.info_log to avoid writing log in
    // SanitizeOptions().
    options.info_log = std::make_shared<DumbLogger>();
    options = SanitizeOptions("db",            // just a place holder
                              &pikc,
                              options);
    GetIntTblPropCollectorFactory(options, &int_tbl_prop_collector_factories);
    options.comparator = comparator;
  } else {
    int_tbl_prop_collector_factories.emplace_back(
        new InternalKeyPropertiesCollectorFactory);
  }
  const ImmutableCFOptions ioptions(options);

  for (int iter = 0; iter < 2; ++iter) {
    MakeBuilder(options, ioptions, pikc, &int_tbl_prop_collector_factories,
                &writable, &builder);
    for (const auto& k : keys) {
      builder->Add(k.Encode(), "val");
    }

    ASSERT_OK(builder->Finish());

    FakeRandomeAccessFile readable(writable->contents());
    TableProperties* props;
    Status s =
        ReadTableProperties(&readable, writable->contents().size(),
                            magic_number, Env::Default(), nullptr, &props);
    ASSERT_OK(s);

    std::unique_ptr<TableProperties> props_guard(props);
    auto user_collected = props->user_collected_properties;
    uint64_t deleted = GetDeletedKeys(user_collected);
    ASSERT_EQ(4u, deleted);

    if (sanitized) {
      uint32_t starts_with_A = 0;
      ASSERT_TRUE(user_collected.find("Count") != user_collected.end());
      Slice key(user_collected.at("Count"));
      ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
      ASSERT_EQ(1u, starts_with_A);

      if (!backward_mode) {
        uint32_t num_deletes;
        ASSERT_TRUE(user_collected.find("NumDeletes") != user_collected.end());
        Slice key_deletes(user_collected.at("NumDeletes"));
        ASSERT_TRUE(GetVarint32(&key_deletes, &num_deletes));
        ASSERT_EQ(4u, num_deletes);

        uint32_t num_puts;
        ASSERT_TRUE(user_collected.find("NumPuts") != user_collected.end());
        Slice key_puts(user_collected.at("NumPuts"));
        ASSERT_TRUE(GetVarint32(&key_puts, &num_puts));
        ASSERT_EQ(3u, num_puts);
      }
    }
  }
}
}  // namespace

TEST_P(TablePropertiesTest, InternalKeyPropertiesCollector) {
  TestInternalKeyPropertiesCollector(
      backward_mode_, kBlockBasedTableMagicNumber, true /* sanitize */,
      std::make_shared<BlockBasedTableFactory>());
  if (backward_mode_) {
    TestInternalKeyPropertiesCollector(
        backward_mode_, kBlockBasedTableMagicNumber, false /* not sanitize */,
        std::make_shared<BlockBasedTableFactory>());
  }

  PlainTableOptions plain_table_options;
  plain_table_options.user_key_len = 8;
  plain_table_options.bloom_bits_per_key = 8;
  plain_table_options.hash_table_ratio = 0;

  TestInternalKeyPropertiesCollector(
      backward_mode_, kPlainTableMagicNumber, false /* not sanitize */,
      std::make_shared<PlainTableFactory>(plain_table_options));
}

INSTANTIATE_TEST_CASE_P(InternalKeyPropertiesCollector, TablePropertiesTest,
                        ::testing::Bool());

INSTANTIATE_TEST_CASE_P(CustomizedTablePropertiesCollector, TablePropertiesTest,
                        ::testing::Bool());

}  // namespace rocksdb

int main(int argc, char** argv) {
  ::testing::InitGoogleTest(&argc, argv);
  return RUN_ALL_TESTS();
}