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

#ifndef CHROMIUMOS_WIDE_PROFILING_TEST_PERF_DATA_H_
#define CHROMIUMOS_WIDE_PROFILING_TEST_PERF_DATA_H_

#include <ostream>  // NOLINT
#include <vector>

#include "chromiumos-wide-profiling/kernel/perf_internals.h"

namespace quipper {
namespace testing {

class StreamWriteable {
 public:
  virtual void WriteTo(std::ostream* out) const = 0;
};

// Normal mode header
class ExamplePerfDataFileHeader : public StreamWriteable {
 public:
  explicit ExamplePerfDataFileHeader(const size_t attr_count,
                                     const unsigned long features);  // NOLINT

  const perf_file_header &header() const { return header_; }
  const ssize_t data_end() const {
    return static_cast<ssize_t>(header_.data.offset + header_.data.size); }

  void WriteTo(std::ostream* out) const override;

 private:
  perf_file_header header_;
};

// Produces a struct perf_file_attr with a perf_event_attr describing a
// tracepoint event.
class ExamplePerfFileAttr_Tracepoint : public StreamWriteable {
 public:
  explicit ExamplePerfFileAttr_Tracepoint(const u64 tracepoint_event_id)
      : tracepoint_event_id_(tracepoint_event_id) {}
  void WriteTo(std::ostream* out) const override;
 private:
  const u64 tracepoint_event_id_;
};

// Produces a struct sample_event matching ExamplePerfFileAttr_Tracepoint.
class ExamplePerfSampleEvent_Tracepoint : public StreamWriteable {
 public:
  ExamplePerfSampleEvent_Tracepoint() {}
  void WriteTo(std::ostream* out) const override;
};

// Produces a struct perf_file_section suitable for use in the metadata index.
class MetadataIndexEntry : public StreamWriteable {
 public:
  MetadataIndexEntry(u64 offset, u64 size)
    : index_entry_{.offset = offset, .size = size} {}
  void WriteTo(std::ostream* out) const override {
    out->write(reinterpret_cast<const char*>(&index_entry_),
               sizeof(index_entry_));
  }
 public:
  const perf_file_section index_entry_;
};

// Produces sample tracing metadata, and corresponding metadata index entry.
class ExampleTracingMetadata {
 public:
  class Data : public StreamWriteable {
   public:
    static const std::vector<char> kTraceMetadata;

    explicit Data(ExampleTracingMetadata* parent) : parent_(parent) {}

    const std::vector<char> value() const { return kTraceMetadata; }

    void WriteTo(std::ostream* out) const override;

   private:
    ExampleTracingMetadata* parent_;
  };

  explicit ExampleTracingMetadata(size_t offset)
      : data_(this), index_entry_(offset, data_.value().size()) {}

  const Data &data() { return data_; }
  const MetadataIndexEntry &index_entry() { return index_entry_; }

 private:
  friend class Data;
  Data data_;
  MetadataIndexEntry index_entry_;
};

}  // namespace testing
}  // namespace quipper

#endif  // CHROMIUMOS_WIDE_PROFILING_TEST_PERF_DATA_H_