// SPDX-FileCopyrightText: 2019-2022 Connor McLaughlin <stenzek@gmail.com>
// SPDX-License-Identifier: (GPL-3.0 OR CC-BY-NC-ND-4.0)

#include "inputbindingdialog.h"
#include "common/bitutils.h"
#include "inputbindingwidgets.h"
#include "qthost.h"
#include "qtutils.h"
#include <QtCore/QTimer>
#include <QtGui/QKeyEvent>
#include <QtGui/QMouseEvent>
#include <QtGui/QWheelEvent>

InputBindingDialog::InputBindingDialog(SettingsInterface* sif, InputBindingInfo::Type bind_type,
                                       std::string section_name, std::string key_name,
                                       std::vector<std::string> bindings, QWidget* parent)
  : QDialog(parent), m_sif(sif), m_bind_type(bind_type), m_section_name(std::move(section_name)),
    m_key_name(std::move(key_name)), m_bindings(std::move(bindings))
{
  m_ui.setupUi(this);
  m_ui.title->setText(
    tr("Bindings for %1 %2").arg(QString::fromStdString(m_section_name)).arg(QString::fromStdString(m_key_name)));
  m_ui.buttonBox->button(QDialogButtonBox::Close)->setText(tr("Close"));

  connect(m_ui.addBinding, &QPushButton::clicked, this, &InputBindingDialog::onAddBindingButtonClicked);
  connect(m_ui.removeBinding, &QPushButton::clicked, this, &InputBindingDialog::onRemoveBindingButtonClicked);
  connect(m_ui.clearBindings, &QPushButton::clicked, this, &InputBindingDialog::onClearBindingsButtonClicked);
  connect(m_ui.buttonBox, &QDialogButtonBox::rejected, [this]() { done(0); });
  updateList();
}

InputBindingDialog::~InputBindingDialog()
{
  Q_ASSERT(!isListeningForInput());
}

bool InputBindingDialog::eventFilter(QObject* watched, QEvent* event)
{
  const QEvent::Type event_type = event->type();

  // if the key is being released, set the input
  if (event_type == QEvent::KeyRelease || event_type == QEvent::MouseButtonRelease)
  {
    addNewBinding();
    stopListeningForInput();
    return true;
  }
  else if (event_type == QEvent::KeyPress)
  {
    const QKeyEvent* key_event = static_cast<const QKeyEvent*>(event);
    m_new_bindings.push_back(InputManager::MakeHostKeyboardKey(QtUtils::KeyEventToCode(key_event)));
    return true;
  }
  else if (event_type == QEvent::MouseButtonPress || event_type == QEvent::MouseButtonDblClick)
  {
    // double clicks get triggered if we click bind, then click again quickly.
    unsigned button_index = CountTrailingZeros(static_cast<u32>(static_cast<const QMouseEvent*>(event)->button()));
    m_new_bindings.push_back(InputManager::MakePointerButtonKey(0, button_index));
    return true;
  }
  else if (event_type == QEvent::Wheel)
  {
    const QPoint delta_angle(static_cast<QWheelEvent*>(event)->angleDelta());
    const float dx = std::clamp(static_cast<float>(delta_angle.x()) / QtUtils::MOUSE_WHEEL_DELTA, -1.0f, 1.0f);
    if (dx != 0.0f)
    {
      InputBindingKey key(InputManager::MakePointerAxisKey(0, InputPointerAxis::WheelX));
      key.modifier = dx < 0.0f ? InputModifier::Negate : InputModifier::None;
      m_new_bindings.push_back(key);
    }

    const float dy = std::clamp(static_cast<float>(delta_angle.y()) / QtUtils::MOUSE_WHEEL_DELTA, -1.0f, 1.0f);
    if (dy != 0.0f)
    {
      InputBindingKey key(InputManager::MakePointerAxisKey(0, InputPointerAxis::WheelY));
      key.modifier = dy < 0.0f ? InputModifier::Negate : InputModifier::None;
      m_new_bindings.push_back(key);
    }

    if (dx != 0.0f || dy != 0.0f)
    {
      addNewBinding();
      stopListeningForInput();
    }

    return true;
  }
  else if (event_type == QEvent::MouseMove && m_mouse_mapping_enabled)
  {
    // if we've moved more than a decent distance from the center of the widget, bind it.
    // this is so we don't accidentally bind to the mouse if you bump it while reaching for your pad.
    static constexpr const s32 THRESHOLD = 50;
    const QPoint diff(static_cast<QMouseEvent*>(event)->globalPosition().toPoint() - m_input_listen_start_position);
    bool has_one = false;

    if (std::abs(diff.x()) >= THRESHOLD)
    {
      InputBindingKey key(InputManager::MakePointerAxisKey(0, InputPointerAxis::X));
      key.modifier = diff.x() < 0 ? InputModifier::Negate : InputModifier::None;
      m_new_bindings.push_back(key);
      has_one = true;
    }
    if (std::abs(diff.y()) >= THRESHOLD)
    {
      InputBindingKey key(InputManager::MakePointerAxisKey(0, InputPointerAxis::Y));
      key.modifier = diff.y() < 0 ? InputModifier::Negate : InputModifier::None;
      m_new_bindings.push_back(key);
      has_one = true;
    }

    if (has_one)
    {
      addNewBinding();
      stopListeningForInput();
      return true;
    }
  }

  return false;
}

void InputBindingDialog::onInputListenTimerTimeout()
{
  m_input_listen_remaining_seconds--;
  if (m_input_listen_remaining_seconds == 0)
  {
    stopListeningForInput();
    return;
  }

  m_ui.status->setText(tr("Push Button/Axis... [%1]").arg(m_input_listen_remaining_seconds));
}

void InputBindingDialog::startListeningForInput(u32 timeout_in_seconds)
{
  m_value_ranges.clear();
  m_new_bindings.clear();
  m_mouse_mapping_enabled = InputBindingWidget::isMouseMappingEnabled(m_sif);
  m_input_listen_start_position = QCursor::pos();
  m_input_listen_timer = new QTimer(this);
  m_input_listen_timer->setSingleShot(false);
  m_input_listen_timer->start(1000);

  m_input_listen_timer->connect(m_input_listen_timer, &QTimer::timeout, this,
                                &InputBindingDialog::onInputListenTimerTimeout);
  m_input_listen_remaining_seconds = timeout_in_seconds;
  m_ui.status->setText(tr("Push Button/Axis... [%1]").arg(m_input_listen_remaining_seconds));
  m_ui.addBinding->setEnabled(false);
  m_ui.removeBinding->setEnabled(false);
  m_ui.clearBindings->setEnabled(false);
  m_ui.buttonBox->setEnabled(false);

  installEventFilter(this);
  grabKeyboard();
  grabMouse();
  setMouseTracking(true);
  hookInputManager();
}

void InputBindingDialog::stopListeningForInput()
{
  m_ui.status->clear();
  m_ui.addBinding->setEnabled(true);
  m_ui.removeBinding->setEnabled(true);
  m_ui.clearBindings->setEnabled(true);
  m_ui.buttonBox->setEnabled(true);

  delete m_input_listen_timer;
  m_input_listen_timer = nullptr;

  unhookInputManager();
  releaseMouse();
  releaseKeyboard();
  setMouseTracking(false);
  removeEventFilter(this);
}

void InputBindingDialog::addNewBinding()
{
  if (m_new_bindings.empty())
    return;

  const std::string new_binding(
    InputManager::ConvertInputBindingKeysToString(m_bind_type, m_new_bindings.data(), m_new_bindings.size()));
  if (!new_binding.empty())
  {
    if (std::find(m_bindings.begin(), m_bindings.end(), new_binding) != m_bindings.end())
      return;

    m_ui.bindingList->addItem(QString::fromStdString(new_binding));
    m_bindings.push_back(std::move(new_binding));
    saveListToSettings();
  }
}

void InputBindingDialog::onAddBindingButtonClicked()
{
  if (isListeningForInput())
    stopListeningForInput();

  startListeningForInput(TIMEOUT_FOR_BINDING);
}

void InputBindingDialog::onRemoveBindingButtonClicked()
{
  const int row = m_ui.bindingList->currentRow();
  if (row < 0 || static_cast<size_t>(row) >= m_bindings.size())
    return;

  m_bindings.erase(m_bindings.begin() + row);
  delete m_ui.bindingList->takeItem(row);
  saveListToSettings();
}

void InputBindingDialog::onClearBindingsButtonClicked()
{
  m_bindings.clear();
  m_ui.bindingList->clear();
  saveListToSettings();
}

void InputBindingDialog::updateList()
{
  m_ui.bindingList->clear();
  for (const std::string& binding : m_bindings)
    m_ui.bindingList->addItem(QString::fromStdString(binding));
}

void InputBindingDialog::saveListToSettings()
{
  if (m_sif)
  {
    if (!m_bindings.empty())
      m_sif->SetStringList(m_section_name.c_str(), m_key_name.c_str(), m_bindings);
    else
      m_sif->DeleteValue(m_section_name.c_str(), m_key_name.c_str());
    m_sif->Save();
    g_emu_thread->reloadGameSettings();
  }
  else
  {
    if (!m_bindings.empty())
      Host::SetBaseStringListSettingValue(m_section_name.c_str(), m_key_name.c_str(), m_bindings);
    else
      Host::DeleteBaseSettingValue(m_section_name.c_str(), m_key_name.c_str());
    Host::CommitBaseSettingChanges();
    g_emu_thread->reloadInputBindings();
  }
}

void InputBindingDialog::inputManagerHookCallback(InputBindingKey key, float value)
{
  if (!isListeningForInput())
    return;

  float initial_value = value;
  float min_value = value;
  auto it = std::find_if(m_value_ranges.begin(), m_value_ranges.end(),
                         [key](const auto& it) { return it.first.bits == key.bits; });
  if (it != m_value_ranges.end())
  {
    initial_value = it->second.first;
    min_value = it->second.second = std::min(it->second.second, value);
  }
  else
  {
    m_value_ranges.emplace_back(key, std::make_pair(initial_value, min_value));
  }

  const float abs_value = std::abs(value);
  const bool reverse_threshold = (key.source_subtype == InputSubclass::ControllerAxis && initial_value > 0.5f);

  for (InputBindingKey& other_key : m_new_bindings)
  {
    if (other_key.MaskDirection() == key.MaskDirection())
    {
      // for pedals, we wait for it to go back to near its starting point to commit the binding
      if ((reverse_threshold ? ((initial_value - value) <= 0.25f) : (abs_value < 0.5f)))
      {
        // did we go the full range?
        if (reverse_threshold && initial_value > 0.5f && min_value <= -0.5f)
          other_key.modifier = InputModifier::FullAxis;

        // if this key is in our new binding list, it's a "release", and we're done
        addNewBinding();
        stopListeningForInput();
        return;
      }

      // otherwise, keep waiting
      return;
    }
  }

  // new binding, add it to the list, but wait for a decent distance first, and then wait for release
  if ((reverse_threshold ? (abs_value < 0.5f) : (abs_value >= 0.5f)))
  {
    InputBindingKey key_to_add = key;
    key_to_add.modifier = (value < 0.0f && !reverse_threshold) ? InputModifier::Negate : InputModifier::None;
    key_to_add.invert = reverse_threshold;
    m_new_bindings.push_back(key_to_add);
  }
}

void InputBindingDialog::hookInputManager()
{
  InputManager::SetHook([this](InputBindingKey key, float value) {
    QMetaObject::invokeMethod(this, "inputManagerHookCallback", Qt::QueuedConnection, Q_ARG(InputBindingKey, key),
                              Q_ARG(float, value));
    return InputInterceptHook::CallbackResult::StopProcessingEvent;
  });
}

void InputBindingDialog::unhookInputManager()
{
  InputManager::RemoveHook();
}