Split //frc971/zeroing into multiple files

It's still a single target, and one massive header file. We should
actually split that up in a future refactoring. However, this does make
it easier to find the relevant parts within each file.

Change-Id: I7abc26f2e3d88da4558f54d56e6db4233cc4c30f
diff --git a/frc971/zeroing/zeroing.h b/frc971/zeroing/zeroing.h
index fe1b461..4d0c1cc 100644
--- a/frc971/zeroing/zeroing.h
+++ b/frc971/zeroing/zeroing.h
@@ -58,169 +58,6 @@
       flatbuffers::FlatBufferBuilder *fbb) const = 0;
 };
 
-// Estimates the position with an incremental encoder with an index pulse and a
-// potentiometer.
-class PotAndIndexPulseZeroingEstimator
-    : public ZeroingEstimator<PotAndIndexPosition,
-                              constants::PotAndIndexPulseZeroingConstants,
-                              EstimatorState> {
- public:
-  explicit PotAndIndexPulseZeroingEstimator(
-      const constants::PotAndIndexPulseZeroingConstants &constants);
-
-  // Update the internal logic with the next sensor values.
-  void UpdateEstimate(const PotAndIndexPosition &info) override;
-
-  // Reset the internal logic so it needs to be re-zeroed.
-  void Reset() override;
-
-  // Manually trigger an internal error. This is used for testing the error
-  // logic.
-  void TriggerError() override;
-
-  bool error() const override { return error_; }
-
-  bool zeroed() const override { return zeroed_; }
-
-  double offset() const override { return offset_; }
-
-  // Returns a number between 0 and 1 that represents the percentage of the
-  // samples being used in the moving average filter. A value of 0.0 means that
-  // no samples are being used. A value of 1.0 means that the filter is using
-  // as many samples as it has room for. For example, after a Reset() this
-  // value returns 0.0. As more samples get added with UpdateEstimate(...) the
-  // return value starts increasing to 1.0.
-  double offset_ratio_ready() const {
-    return start_pos_samples_.size() /
-           static_cast<double>(constants_.average_filter_size);
-  }
-
-  // Returns true if the sample buffer is full.
-  bool offset_ready() const override {
-    return start_pos_samples_.size() == constants_.average_filter_size;
-  }
-
-  // Returns information about our current state.
-  virtual flatbuffers::Offset<State> GetEstimatorState(
-      flatbuffers::FlatBufferBuilder *fbb) const override;
-
- private:
-  // This function calculates the start position given the internal state and
-  // the provided `latched_encoder' value.
-  double CalculateStartPosition(double start_average,
-                                double latched_encoder) const;
-
-  // The zeroing constants used to describe the configuration of the system.
-  const constants::PotAndIndexPulseZeroingConstants constants_;
-
-  // The estimated position.
-  double position_;
-  // The unzeroed filtered position.
-  double filtered_position_ = 0.0;
-  // The next position in 'start_pos_samples_' to be used to store the next
-  // sample.
-  int samples_idx_;
-  // Last 'max_sample_count_' samples for start positions.
-  std::vector<double> start_pos_samples_;
-  // The estimated starting position of the mechanism. We also call this the
-  // 'offset' in some contexts.
-  double offset_;
-  // Flag for triggering logic that takes note of the current index pulse count
-  // after a reset. See `last_used_index_pulse_count_'.
-  bool wait_for_index_pulse_;
-  // After a reset we keep track of the index pulse count with this. Only after
-  // the index pulse count changes (i.e. increments at least once or wraps
-  // around) will we consider the mechanism zeroed. We also use this to store
-  // the most recent `PotAndIndexPosition::index_pulses' value when the start
-  // position was calculated. It helps us calculate the start position only on
-  // index pulses to reject corrupted intermediate data.
-  uint32_t last_used_index_pulse_count_;
-  // Marker to track whether we're fully zeroed yet or not.
-  bool zeroed_;
-  // Marker to track whether an error has occurred. This gets reset to false
-  // whenever Reset() is called.
-  bool error_;
-  // Stores the position "start_pos" variable the first time the program
-  // is zeroed.
-  double first_start_pos_;
-};
-
-// Estimates the position with an incremental encoder and a hall effect sensor.
-class HallEffectAndPositionZeroingEstimator
-    : public ZeroingEstimator<HallEffectAndPosition,
-                              constants::HallEffectZeroingConstants,
-                              HallEffectAndPositionEstimatorState> {
- public:
-  explicit HallEffectAndPositionZeroingEstimator(
-      const ZeroingConstants &constants);
-
-  // Update the internal logic with the next sensor values.
-  void UpdateEstimate(const Position &info) override;
-
-  // Reset the internal logic so it needs to be re-zeroed.
-  void Reset() override;
-
-  // Manually trigger an internal error. This is used for testing the error
-  // logic.
-  void TriggerError() override;
-
-  bool error() const override { return error_; }
-
-  bool zeroed() const override { return zeroed_; }
-
-  double offset() const override { return offset_; }
-
-  bool offset_ready() const override { return zeroed_; }
-
-  // Returns information about our current state.
-  virtual flatbuffers::Offset<State> GetEstimatorState(
-      flatbuffers::FlatBufferBuilder *fbb) const override;
-
- private:
-  // Sets the minimum and maximum posedge position values.
-  void StoreEncoderMaxAndMin(const HallEffectAndPosition &info);
-
-  // The zeroing constants used to describe the configuration of the system.
-  const ZeroingConstants constants_;
-
-  // The estimated state of the hall effect.
-  double current_ = 0.0;
-  // The estimated position.
-  double position_ = 0.0;
-  // The smallest and largest positions of the last set of encoder positions
-  // while the hall effect was low.
-  double min_low_position_;
-  double max_low_position_;
-  // If we've seen the hall effect high for enough times without going low, then
-  // we can be sure it isn't a false positive.
-  bool high_long_enough_;
-  size_t cycles_high_;
-
-  bool last_hall_ = false;
-
-  // The estimated starting position of the mechanism. We also call this the
-  // 'offset' in some contexts.
-  double offset_;
-  // Flag for triggering logic that takes note of the current posedge count
-  // after a reset. See `last_used_posedge_count_'.
-  bool initialized_;
-  // After a reset we keep track of the posedge count with this. Only after the
-  // posedge count changes (i.e. increments at least once or wraps around) will
-  // we consider the mechanism zeroed. We also use this to store the most recent
-  // `HallEffectAndPosition::posedge_count' value when the start position
-  // was calculated. It helps us calculate the start position only on posedges
-  // to reject corrupted intermediate data.
-  int32_t last_used_posedge_count_;
-  // Marker to track whether we're fully zeroed yet or not.
-  bool zeroed_;
-  // Marker to track whether an error has occurred. This gets reset to false
-  // whenever Reset() is called.
-  bool error_ = false;
-  // Stores the position "start_pos" variable the first time the program
-  // is zeroed.
-  double first_start_pos_;
-};
-
 // Class to encapsulate the logic to decide when we are moving and which samples
 // are safe to use.
 template <typename Position, typename PositionBuffer>
@@ -287,237 +124,7 @@
   size_t buffered_samples_idx_;
 };
 
-// Estimates the position with an absolute encoder which also reports
-// incremental counts, and a potentiometer.
-class PotAndAbsoluteEncoderZeroingEstimator
-    : public ZeroingEstimator<PotAndAbsolutePosition,
-                              constants::PotAndAbsoluteEncoderZeroingConstants,
-                              PotAndAbsoluteEncoderEstimatorState> {
- public:
-  explicit PotAndAbsoluteEncoderZeroingEstimator(
-      const constants::PotAndAbsoluteEncoderZeroingConstants &constants);
-
-  // Resets the internal logic so it needs to be re-zeroed.
-  void Reset() override;
-
-  // Updates the sensor values for the zeroing logic.
-  void UpdateEstimate(const PotAndAbsolutePosition &info) override;
-
-  void TriggerError() override { error_ = true; }
-
-  bool zeroed() const override { return zeroed_; }
-
-  double offset() const override { return offset_; }
-
-  bool error() const override { return error_; }
-
-  // Returns true if the sample buffer is full.
-  bool offset_ready() const override {
-    return relative_to_absolute_offset_samples_.size() ==
-               constants_.average_filter_size &&
-           offset_samples_.size() == constants_.average_filter_size;
-  }
-
-  // Returns information about our current state.
-  virtual flatbuffers::Offset<State> GetEstimatorState(
-      flatbuffers::FlatBufferBuilder *fbb) const override;
-
- private:
-  struct PositionStruct {
-    PositionStruct(const PotAndAbsolutePosition &position_buffer)
-        : absolute_encoder(position_buffer.absolute_encoder()),
-          encoder(position_buffer.encoder()),
-          pot(position_buffer.pot()) {}
-    double absolute_encoder;
-    double encoder;
-    double pot;
-  };
-
-  // The zeroing constants used to describe the configuration of the system.
-  const constants::PotAndAbsoluteEncoderZeroingConstants constants_;
-
-  // True if the mechanism is zeroed.
-  bool zeroed_;
-  // Marker to track whether an error has occurred.
-  bool error_;
-  // The first valid offset we recorded. This is only set after zeroed_ first
-  // changes to true.
-  double first_offset_;
-
-  // The filtered absolute encoder.  This is used in the status for calibration.
-  double filtered_absolute_encoder_ = 0.0;
-
-  // Samples of the offset needed to line the relative encoder up with the
-  // absolute encoder.
-  ::std::vector<double> relative_to_absolute_offset_samples_;
-  // Offset between the Pot and Relative encoder position.
-  ::std::vector<double> offset_samples_;
-
-  MoveDetector<PositionStruct, PotAndAbsolutePosition> move_detector_;
-
-  // Estimated offset between the pot and relative encoder.
-  double pot_relative_encoder_offset_ = 0;
-  // Estimated start position of the mechanism
-  double offset_ = 0;
-  // The next position in 'relative_to_absolute_offset_samples_' and
-  // 'encoder_samples_' to be used to store the next sample.
-  int samples_idx_ = 0;
-
-  size_t nan_samples_ = 0;
-
-  // The unzeroed filtered position.
-  double filtered_position_ = 0.0;
-  // The filtered position.
-  double position_ = 0.0;
-};
-
-// Zeros by seeing all the index pulses in the range of motion of the mechanism
-// and using that to figure out which index pulse is which.
-class PulseIndexZeroingEstimator
-    : public ZeroingEstimator<IndexPosition,
-                              constants::EncoderPlusIndexZeroingConstants,
-                              IndexEstimatorState> {
- public:
-  explicit PulseIndexZeroingEstimator(const ZeroingConstants &constants)
-      : constants_(constants) {
-    Reset();
-  }
-
-  // Resets the internal logic so it needs to be re-zeroed.
-  void Reset() override;
-
-  bool zeroed() const override { return zeroed_; }
-
-  // It's as ready as it'll ever be...
-  bool offset_ready() const override { return true; }
-
-  double offset() const override { return offset_; }
-
-  bool error() const override { return error_; }
-
-  // Updates the internal logic with the next sensor values.
-  void UpdateEstimate(const IndexPosition &info) override;
-
-  // Returns information about our current state.
-  virtual flatbuffers::Offset<State> GetEstimatorState(
-      flatbuffers::FlatBufferBuilder *fbb) const override;
-
-  void TriggerError() override { error_ = true; }
-
- private:
-  // Returns the current real position using the relative encoder offset.
-  double CalculateCurrentPosition(const IndexPosition &info);
-
-  // Sets the minimum and maximum index pulse position values.
-  void StoreIndexPulseMaxAndMin(const IndexPosition &info);
-
-  // Returns the number of index pulses we should have seen so far.
-  int IndexPulseCount() const;
-
-  // Contains the physical constants describing the system.
-  const ZeroingConstants constants_;
-
-  // The smallest position of all the index pulses.
-  double min_index_position_;
-  // The largest position of all the index pulses.
-  double max_index_position_;
-
-  // The estimated starting position of the mechanism.
-  double offset_;
-  // After a reset we keep track of the index pulse count with this. Only after
-  // the index pulse count changes (i.e. increments at least once or wraps
-  // around) will we consider the mechanism zeroed. We also use this to store
-  // the most recent `PotAndIndexPosition::index_pulses' value when the start
-  // position was calculated. It helps us calculate the start position only on
-  // index pulses to reject corrupted intermediate data.
-  uint32_t last_used_index_pulse_count_;
-
-  // True if we are fully zeroed.
-  bool zeroed_;
-  // Marker to track whether an error has occurred.
-  bool error_;
-
-  // The estimated position.
-  double position_;
-};
-
-// Estimates the position with an absolute encoder which also reports
-// incremental counts.  The absolute encoder can't spin more than one
-// revolution.
-class AbsoluteEncoderZeroingEstimator
-    : public ZeroingEstimator<AbsolutePosition,
-                              constants::AbsoluteEncoderZeroingConstants,
-                              AbsoluteEncoderEstimatorState> {
- public:
-  explicit AbsoluteEncoderZeroingEstimator(
-      const constants::AbsoluteEncoderZeroingConstants &constants);
-
-  // Resets the internal logic so it needs to be re-zeroed.
-  void Reset() override;
-
-  // Updates the sensor values for the zeroing logic.
-  void UpdateEstimate(const AbsolutePosition &info) override;
-
-  void TriggerError() override { error_ = true; }
-
-  bool zeroed() const override { return zeroed_; }
-
-  double offset() const override { return offset_; }
-
-  bool error() const override { return error_; }
-
-  // Returns true if the sample buffer is full.
-  bool offset_ready() const override {
-    return relative_to_absolute_offset_samples_.size() ==
-           constants_.average_filter_size;
-  }
-
-  // Returns information about our current state.
-  virtual flatbuffers::Offset<State> GetEstimatorState(
-      flatbuffers::FlatBufferBuilder *fbb) const override;
-
- private:
-  struct PositionStruct {
-    PositionStruct(const AbsolutePosition &position_buffer)
-        : absolute_encoder(position_buffer.absolute_encoder()),
-          encoder(position_buffer.encoder()) {}
-    double absolute_encoder;
-    double encoder;
-  };
-
-  // The zeroing constants used to describe the configuration of the system.
-  const constants::AbsoluteEncoderZeroingConstants constants_;
-
-  // True if the mechanism is zeroed.
-  bool zeroed_;
-  // Marker to track whether an error has occurred.
-  bool error_;
-  // The first valid offset we recorded. This is only set after zeroed_ first
-  // changes to true.
-  double first_offset_;
-
-  // The filtered absolute encoder.  This is used in the status for calibration.
-  double filtered_absolute_encoder_ = 0.0;
-
-  // Samples of the offset needed to line the relative encoder up with the
-  // absolute encoder.
-  ::std::vector<double> relative_to_absolute_offset_samples_;
-
-  MoveDetector<PositionStruct, AbsolutePosition> move_detector_;
-
-  // Estimated start position of the mechanism
-  double offset_ = 0;
-  // The next position in 'relative_to_absolute_offset_samples_' and
-  // 'encoder_samples_' to be used to store the next sample.
-  int samples_idx_ = 0;
-
-  // Number of NANs we've seen in a row.
-  size_t nan_samples_ = 0;
-
-  // The filtered position.
-  double position_ = 0.0;
-};
-
+// A trivial ZeroingEstimator which just passes the position straight through.
 class RelativeEncoderZeroingEstimator
     : public ZeroingEstimator<RelativePosition, void,
                               RelativeEncoderEstimatorState> {
@@ -562,4 +169,12 @@
 }  // namespace zeroing
 }  // namespace frc971
 
+// TODO(Brian): Actually split these targets apart. Need to convert all the
+// reverse dependencies to #include what they actually need...
+#include "frc971/zeroing/absolute_encoder.h"
+#include "frc971/zeroing/hall_effect_and_position.h"
+#include "frc971/zeroing/pot_and_absolute_encoder.h"
+#include "frc971/zeroing/pot_and_index.h"
+#include "frc971/zeroing/pulse_index.h"
+
 #endif  // FRC971_ZEROING_ZEROING_H_