#include "Geometry/GEMGeometry/interface/ME0Chamber.h"
#include "Geometry/GEMGeometry/interface/ME0Layer.h"
#include "Geometry/GEMGeometry/interface/ME0EtaPartition.h"
#include <iostream>

ME0Chamber::ME0Chamber(ME0DetId id, const ReferenceCountingPointer<BoundPlane>& plane) : GeomDet(plane), detId_(id) {
  setDetId(id);
}

ME0Chamber::~ME0Chamber() {}

ME0DetId ME0Chamber::id() const { return detId_; }

bool ME0Chamber::operator==(const ME0Chamber& ch) const { return this->id() == ch.id(); }

void ME0Chamber::add(ME0Layer* rl) { layers_.emplace_back(rl); }

std::vector<const GeomDet*> ME0Chamber::components() const {
  return std::vector<const GeomDet*>(layers_.begin(), layers_.end());
}

const GeomDet* ME0Chamber::component(DetId id) const { return layer(ME0DetId(id.rawId())); }

const std::vector<const ME0Layer*>& ME0Chamber::layers() const { return layers_; }

int ME0Chamber::nLayers() const { return layers_.size(); }

const ME0Layer* ME0Chamber::layer(ME0DetId id) const {
  if (id.chamberId() != detId_)
    return nullptr;  // not in this layer!
  return layer(id.layer());
}

const ME0Layer* ME0Chamber::layer(int isl) const {
  for (auto layer : layers_) {
    if (layer->id().layer() == isl)
      return layer;
  }
  return nullptr;
}

// For the old ME0 Geometry (with one eta partition)
// we need to maintain this for a while
void ME0Chamber::add(ME0EtaPartition* rl) { etaPartitions_.emplace_back(rl); }

const std::vector<const ME0EtaPartition*>& ME0Chamber::etaPartitions() const { return etaPartitions_; }

int ME0Chamber::nEtaPartitions() const { return etaPartitions_.size(); }

const ME0EtaPartition* ME0Chamber::etaPartition(ME0DetId id) const {
  if (id.chamberId() != detId_)
    return nullptr;  // not in this eta partition!
  return etaPartition(id.roll());
}

const ME0EtaPartition* ME0Chamber::etaPartition(int isl) const {
  for (auto roll : etaPartitions_) {
    if (roll->id().roll() == isl)
      return roll;
  }
  return nullptr;
}

float ME0Chamber::computeDeltaPhi(const LocalPoint& position, const LocalVector& direction) const {
  auto extrap = [](const LocalPoint& point, const LocalVector& dir, double extZ) -> LocalPoint {
    double extX = point.x() + extZ * dir.x() / dir.z();
    double extY = point.y() + extZ * dir.y() / dir.z();
    return LocalPoint(extX, extY, extZ);
  };
  if (nLayers() < 2) {
    return 0;
  }

  const float beginOfChamber = layer(1)->position().z();
  const float centerOfChamber = this->position().z();
  const float endOfChamber = layer(nLayers())->position().z();

  LocalPoint projHigh =
      extrap(position, direction, (centerOfChamber < 0 ? -1.0 : 1.0) * (endOfChamber - centerOfChamber));
  LocalPoint projLow =
      extrap(position, direction, (centerOfChamber < 0 ? -1.0 : 1.0) * (beginOfChamber - centerOfChamber));
  auto globLow = toGlobal(projLow);
  auto globHigh = toGlobal(projHigh);
  return globHigh.phi() - globLow.phi();  //Geom::phi automatically normalizes to [-pi, pi]
}