// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/metrics/serialization/metric_sample.h"

#include <string>
#include <vector>

#include "base/check_op.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_piece.h"
#include "base/strings/string_split.h"
#include "base/strings/stringprintf.h"

namespace metrics {

MetricSample::MetricSample(MetricSample::SampleType sample_type,
                           const std::string& metric_name,
                           int sample,
                           int min,
                           int max,
                           int bucket_count,
                           int num_samples)
    : type_(sample_type),
      name_(metric_name),
      sample_(sample),
      min_(min),
      max_(max),
      bucket_count_(bucket_count),
      num_samples_(num_samples) {}

MetricSample::~MetricSample() {
}

bool MetricSample::IsValid() const {
  return name().find(' ') == std::string::npos &&
         name().find('\0') == std::string::npos && !name().empty();
}

std::string MetricSample::ToString() const {
  std::string samples =
      (num_samples_ == 1) ? "" : base::StringPrintf(" %d", num_samples_);
  if (type_ == CRASH) {
    return base::StringPrintf("crash%c%s%s%c", '\0', name().c_str(),
                              samples.c_str(), '\0');
  }
  if (type_ == SPARSE_HISTOGRAM) {
    return base::StringPrintf("sparsehistogram%c%s %d%s%c", '\0',
                              name().c_str(), sample_, samples.c_str(), '\0');
  }
  if (type_ == LINEAR_HISTOGRAM) {
    return base::StringPrintf("linearhistogram%c%s %d %d%s%c", '\0',
                              name().c_str(), sample_, max_, samples.c_str(),
                              '\0');
  }
  if (type_ == HISTOGRAM) {
    return base::StringPrintf("histogram%c%s %d %d %d %d%s%c", '\0',
                              name().c_str(), sample_, min_, max_,
                              bucket_count_, samples.c_str(), '\0');
  }
  // The type can only be USER_ACTION.
  CHECK_EQ(type_, USER_ACTION);
  return base::StringPrintf("useraction%c%s%s%c", '\0', name().c_str(),
                            samples.c_str(), '\0');
}

int MetricSample::sample() const {
  CHECK_NE(type_, USER_ACTION);
  CHECK_NE(type_, CRASH);
  return sample_;
}

int MetricSample::min() const {
  CHECK_EQ(type_, HISTOGRAM);
  return min_;
}

int MetricSample::max() const {
  CHECK_NE(type_, CRASH);
  CHECK_NE(type_, USER_ACTION);
  CHECK_NE(type_, SPARSE_HISTOGRAM);
  return max_;
}

int MetricSample::bucket_count() const {
  CHECK_EQ(type_, HISTOGRAM);
  return bucket_count_;
}

// static
std::unique_ptr<MetricSample> MetricSample::CrashSample(
    const std::string& crash_name,
    int num_samples) {
  return std::make_unique<MetricSample>(CRASH, crash_name, 0, 0, 0, 0,
                                        num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::ParseCrash(
    const std::string& serialized) {
  std::vector<base::StringPiece> parts = base::SplitStringPiece(
      serialized, " ", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);

  if (parts.size() != 1 && parts.size() != 2) {
    return nullptr;
  }
  if (parts[0].empty()) {
    return nullptr;
  }
  int num_samples = 1;
  if (parts.size() == 2) {
    if (!base::StringToInt(parts[1], &num_samples) || num_samples <= 0) {
      return nullptr;
    }
  }

  return CrashSample(std::string(parts[0]), num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::HistogramSample(
    const std::string& histogram_name,
    int sample,
    int min,
    int max,
    int bucket_count,
    int num_samples) {
  return std::make_unique<MetricSample>(HISTOGRAM, histogram_name, sample, min,
                                        max, bucket_count, num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::ParseHistogram(
    const std::string& serialized_histogram) {
  std::vector<base::StringPiece> parts = base::SplitStringPiece(
      serialized_histogram, " ", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);

  if (parts.size() != 5 && parts.size() != 6) {
    return nullptr;
  }
  int sample, min, max, bucket_count;
  if (parts[0].empty() || !base::StringToInt(parts[1], &sample) ||
      !base::StringToInt(parts[2], &min) ||
      !base::StringToInt(parts[3], &max) ||
      !base::StringToInt(parts[4], &bucket_count)) {
    return nullptr;
  }
  int num_samples = 1;
  if (parts.size() == 6) {
    if (!base::StringToInt(parts[5], &num_samples) || num_samples <= 0) {
      return nullptr;
    }
  }

  return HistogramSample(std::string(parts[0]), sample, min, max, bucket_count,
                         num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::SparseHistogramSample(
    const std::string& histogram_name,
    int sample,
    int num_samples) {
  return std::make_unique<MetricSample>(SPARSE_HISTOGRAM, histogram_name,
                                        sample, 0, 0, 0, num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::ParseSparseHistogram(
    const std::string& serialized_histogram) {
  std::vector<base::StringPiece> parts = base::SplitStringPiece(
      serialized_histogram, " ", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
  if (parts.size() != 2 && parts.size() != 3) {
    return nullptr;
  }
  int sample;
  if (parts[0].empty() || !base::StringToInt(parts[1], &sample))
    return nullptr;

  int num_samples = 1;
  if (parts.size() == 3) {
    if (!base::StringToInt(parts[2], &num_samples) || num_samples <= 0) {
      return nullptr;
    }
  }

  return SparseHistogramSample(std::string(parts[0]), sample, num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::LinearHistogramSample(
    const std::string& histogram_name,
    int sample,
    int max,
    int num_samples) {
  return std::make_unique<MetricSample>(LINEAR_HISTOGRAM, histogram_name,
                                        sample, 0, max, 0, num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::ParseLinearHistogram(
    const std::string& serialized_histogram) {
  std::vector<base::StringPiece> parts = base::SplitStringPiece(
      serialized_histogram, " ", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
  int sample, max;
  if (parts.size() != 3 && parts.size() != 4) {
    return nullptr;
  }
  if (parts[0].empty() || !base::StringToInt(parts[1], &sample) ||
      !base::StringToInt(parts[2], &max)) {
    return nullptr;
  }

  int num_samples = 1;
  if (parts.size() == 4) {
    if (!base::StringToInt(parts[3], &num_samples) || num_samples <= 0) {
      return nullptr;
    }
  }

  return LinearHistogramSample(std::string(parts[0]), sample, max, num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::UserActionSample(
    const std::string& action_name,
    int num_samples) {
  return std::make_unique<MetricSample>(USER_ACTION, action_name, 0, 0, 0, 0,
                                        num_samples);
}

// static
std::unique_ptr<MetricSample> MetricSample::ParseUserAction(
    const std::string& serialized) {
  std::vector<base::StringPiece> parts = base::SplitStringPiece(
      serialized, " ", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);

  if (parts.size() != 1 && parts.size() != 2) {
    return nullptr;
  }
  if (parts[0].empty()) {
    return nullptr;
  }
  int num_samples = 1;
  if (parts.size() == 2) {
    if (!base::StringToInt(parts[1], &num_samples) || num_samples <= 0) {
      return nullptr;
    }
  }

  return UserActionSample(std::string(parts[0]), num_samples);
}

bool MetricSample::IsEqual(const MetricSample& metric) {
  return type_ == metric.type_ && name_ == metric.name_ &&
         sample_ == metric.sample_ && min_ == metric.min_ &&
         max_ == metric.max_ && bucket_count_ == metric.bucket_count_ &&
         num_samples_ == metric.num_samples_;
}

}  // namespace metrics