//----------------------------------------------------------------------
// Includes
//----------------------------------------------------------------------
#include "MantidAPI/FunctionValues.h"
#include <algorithm>

namespace Mantid {
namespace API {

/**
 * Constructs a set of output values based on the given domain.
 * @param domain :: A reference to the domain over which the function is
 * calculated
 */
FunctionValues::FunctionValues(const FunctionDomain &domain) { reset(domain); }

/** Copy constructor.
 *  @param values :: Values to copy from.
 */
FunctionValues::FunctionValues(const FunctionValues &values)
    : m_calculated(values.m_calculated), m_data(values.m_data),
      m_weights(values.m_weights) {}

/// Destructor
FunctionValues::~FunctionValues() {}

/// Reset the values to match a new domain.
void FunctionValues::reset(const FunctionDomain &domain) {
  if (domain.size() == 0) {
    throw std::invalid_argument("FunctionValues cannot have zero size.");
  }
  m_calculated.resize(domain.size());
}

/**
 * Expand to a new size. Preserve old values. Do not contract.
 * @param n :: A new size, must be greater than the current size.
 */
void FunctionValues::expand(size_t n) {
  if (n < size()) {
    throw std::invalid_argument("Cannot make FunctionValues smaller");
  }
  m_calculated.resize(n);
  if (!m_data.empty()) {
    m_data.resize(n);
  }
  if (!m_weights.empty()) {
    m_weights.resize(n);
  }
}

/** Set all calculated values to same number.
 * @param value :: A new value.
 */
void FunctionValues::setCalculated(double value) {
  std::fill(m_calculated.begin(), m_calculated.end(), value);
}

/**
 * Get a pointer to calculated data at index i
 * @param i :: Index.
 */
double *FunctionValues::getPointerToCalculated(size_t i) {
  if (i < size()) {
    return &m_calculated[i];
  }
  throw std::out_of_range("FunctionValue index out of range.");
}

/// Set all calculated values to zero
void FunctionValues::zeroCalculated() { setCalculated(0.0); }

/**
 * Copy calculated values to a buffer
 * @param to :: Pointer to the buffer
 */
void FunctionValues::copyTo(double *to) const {
  std::copy(m_calculated.begin(), m_calculated.end(), to);
}

/** Add calculated values to values in a buffer and save result to the buffer
 * @param to :: Pointer to the buffer, it must be large enough
 */
void FunctionValues::add(double *to) const {
  std::transform(m_calculated.begin(), m_calculated.end(), to, to,
                 std::plus<double>());
}

/** Multiply calculated values by values in a buffer and save result to the
 * buffer
 * @param to :: Pointer to the buffer, it must be large enough
 */
void FunctionValues::multiply(double *to) const {
  std::transform(m_calculated.begin(), m_calculated.end(), to, to,
                 std::multiplies<double>());
}

/**
 * Add other calculated values to this.
 * @param values :: An instance of FunctionValues to be added to this. Must have
 * the same size to this.
 * @return A reference to this values.
 */
FunctionValues &FunctionValues::operator+=(const FunctionValues &values) {
  if (size() != values.size()) {
    throw std::runtime_error("Cannot add values: sizes do not match");
  }
  values.add(getPointerToCalculated(0));
  return *this;
}

/**
 * Multiply by other calculated values.
 * @param values :: An instance of FunctionValues to multiply to this. Must have
 * the same size to this.
 * @return A reference to this values.
 */
FunctionValues &FunctionValues::operator*=(const FunctionValues &values) {
  if (size() != values.size()) {
    throw std::runtime_error("Cannot multiply values: sizes do not match");
  }
  values.multiply(getPointerToCalculated(0));
  return *this;
}

/**
 * Add other calculated values to these values starting from some index.
 * @param start :: A starting index for addition
 * @param values :: An instance of FunctionValues to be added to this. The size
 * mustn't exceed the number of
 *   values in this from start to the end.
 * @return A reference to this values.
 */
void FunctionValues::addToCalculated(size_t start,
                                     const FunctionValues &values) {
  if (start + size() < values.size()) {
    throw std::runtime_error("Cannot add values: sizes do not match");
  }
  values.add(getPointerToCalculated(start));
}

/**
 * Set a fitting data value.
 * @param i :: A value index
 * @param value :: A new value to set.
 */
void FunctionValues::setFitData(size_t i, double value) {
  if (m_data.size() != m_calculated.size()) {
    m_data.resize(m_calculated.size());
  }
  m_data[i] = value;
}

/**
 * Set all fitting data values.
 * @param values :: A vector of values for fitting. Must have the same size as
 * this.
 */
void FunctionValues::setFitData(const std::vector<double> &values) {
  if (values.size() != this->size()) {
    throw std::invalid_argument("Setting data of a wrong size");
  }
  m_data.assign(values.begin(), values.end());
}

/**
 * Get a fitting data value
 * @param i :: A value index
 */
double FunctionValues::getFitData(size_t i) const {
  if (m_data.size() != m_calculated.size()) {
    throw std::runtime_error("Fitting data was not set");
  }
  return m_data[i];
}

/**
 * Set a fitting weight
 * @param i :: A value index
 * @param value :: A new value for the weight.
 */
void FunctionValues::setFitWeight(size_t i, double value) {
  if (m_weights.size() != m_calculated.size()) {
    m_weights.resize(m_calculated.size());
  }
  m_weights[i] = value;
}

/**
 * Set all fitting weights.
 * @param values :: A vector of fitting weights. Must have the same size as
 * this.
 */
void FunctionValues::setFitWeights(const std::vector<double> &values) {
  if (values.size() != this->size()) {
    throw std::invalid_argument("Setting data of a wrong size");
  }
  m_weights.assign(values.begin(), values.end());
}

/**
 * Set all weights to the same value.
 * @param value :: The value to set.
 */
void FunctionValues::setFitWeights(const double &value) {
  m_weights.resize(m_calculated.size(), value);
}

/**
 * Get a fitting weight.
 * @param i :: A value index.
 */
double FunctionValues::getFitWeight(size_t i) const {
  if (m_weights.size() != m_calculated.size()) {
    throw std::runtime_error("Fitting weights was not set");
  }
  return m_weights[i];
}

/**
 * Set fitting data copied from other FunctionValues' calculated values.
 * @param values :: An instance of FunctionValues to copy the data from.
 */
void FunctionValues::setFitDataFromCalculated(const FunctionValues &values) {
  m_data.assign(values.m_calculated.begin(), values.m_calculated.end());
}

} // namespace API
} // namespace Mantid