#include "calculation_graph_controller.h"
#include "../app.h"

using namespace Shared;
using namespace Poincare;

namespace Graph {

CalculationGraphController::CalculationGraphController(Responder * parentResponder, GraphView * graphView, BannerView * bannerView, Shared::InteractiveCurveViewRange * curveViewRange, CurveViewCursor * cursor, I18n::Message defaultMessage) :
  ViewController(parentResponder),
  m_graphView(graphView),
  m_bannerView(bannerView),
  m_graphRange(curveViewRange),
  m_cursor(cursor),
  m_function(nullptr),
  m_defaultBannerView(KDText::FontSize::Small, defaultMessage, 0.5f, 0.5f, KDColorBlack, Palette::GreyMiddle),
  m_isActive(false)
{
}

View * CalculationGraphController::view() {
  return m_graphView;
}

void CalculationGraphController::viewWillAppear() {
  assert(m_function != nullptr);
  Expression::Coordinate2D pointOfInterest = computeNewPointOfInteresetFromAbscissa(m_graphRange->xMin(), 1);
  if (std::isnan(pointOfInterest.abscissa)) {
    m_isActive = false;
    m_graphView->setCursorView(nullptr);
    m_graphView->setBannerView(&m_defaultBannerView);
  } else {
    m_isActive = true;
    m_cursor->moveTo(pointOfInterest.abscissa, pointOfInterest.value);
    m_graphRange->panToMakePointVisible(m_cursor->x(), m_cursor->y(), k_cursorTopMarginRatio, SimpleInteractiveCurveViewController::k_cursorRightMarginRatio, k_cursorBottomMarginRatio, SimpleInteractiveCurveViewController::k_cursorLeftMarginRatio);
    reloadBannerView();
  }
  m_graphView->setOkView(nullptr);
  m_graphView->reload();
}

bool CalculationGraphController::handleEvent(Ion::Events::Event event) {
  if (event == Ion::Events::EXE || event == Ion::Events::OK) {
    StackViewController * stack = static_cast<StackViewController *>(parentResponder());
    stack->pop();
    return true;
  }
  if (m_isActive && (event == Ion::Events::Right || event == Ion::Events::Left)) {
    int direction = event == Ion::Events::Right ? 1 : -1;
    if (moveCursor(direction)) {
      reloadBannerView();
      m_graphView->reload();
      return true;
    }
  }
  return false;
}

void CalculationGraphController::setFunction(CartesianFunction * function) {
  m_graphView->selectFunction(function);
  m_function = function;
}

void CalculationGraphController::reloadBannerView() {
  m_bannerView->setNumberOfSubviews(2);
  reloadBannerViewForCursorOnFunction(m_cursor, m_function, 'x');
}

bool CalculationGraphController::moveCursor(int direction) {
  Expression::Coordinate2D newPointOfInterest = computeNewPointOfInteresetFromAbscissa(m_cursor->x(), direction);
  if (std::isnan(newPointOfInterest.abscissa)) {
    return false;
  }
  m_cursor->moveTo(newPointOfInterest.abscissa, newPointOfInterest.value);
  m_graphRange->panToMakePointVisible(m_cursor->x(), m_cursor->y(), k_cursorTopMarginRatio, SimpleInteractiveCurveViewController::k_cursorRightMarginRatio, k_cursorBottomMarginRatio, SimpleInteractiveCurveViewController::k_cursorLeftMarginRatio);
  return true;
}

Expression::Coordinate2D CalculationGraphController::computeNewPointOfInteresetFromAbscissa(double start, int direction) {
  TextFieldDelegateApp * myApp = (TextFieldDelegateApp *)app();
  double step = m_graphRange->xGridUnit()/10.0;
  step = direction < 0 ? -step : step;
  double max = direction > 0 ? m_graphRange->xMax() : m_graphRange->xMin();
  return computeNewPointOfInterest(start, step, max, myApp->localContext());
}

}