/*
 * Copyright (C) EdgeTX
 *
 * Based on code named
 *   opentx - https://github.com/opentx/opentx
 *   th9x - http://code.google.com/p/th9x
 *   er9x - http://code.google.com/p/er9x
 *   gruvin9x - http://code.google.com/p/gruvin9x
 *
 * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Based on
 *
    Elypson/qt-collapsible-section
    (c) 2016 Michael A. Voelkel - michael.alexander.voelkel@gmail.com

    This file is part of Elypson/qt-collapsible section.

    Elypson/qt-collapsible-section is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    Elypson/qt-collapsible-section is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Elypson/qt-collapsible-section. If not, see <http://www.gnu.org/licenses/>.
*/

#include "autocollapsiblesection.h"

#include <QPropertyAnimation>

AutoCollapsibleSection::AutoCollapsibleSection(QWidget * parent) :
  QWidget(parent),
  AutoWidget(parent),
  fnResize(nullptr)
{
  toggleButton = new QToolButton(this);
  headerLine = new QFrame(this);
  toggleAnimation = new QParallelAnimationGroup(this);
  contentArea = new QScrollArea(this);
  contentAreaLayout = new QGridLayout();
  mainLayout = new QGridLayout(this);

  toggleButton->setStyleSheet("QToolButton {border: none;}");
  toggleButton->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
  toggleButton->setArrowType(Qt::ArrowType::RightArrow);
  toggleButton->setText(title);
  toggleButton->setCheckable(true);
  toggleButton->setChecked(false);

  headerLine->setFrameShape(QFrame::HLine);
  headerLine->setFrameShadow(QFrame::Sunken);
  headerLine->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Maximum);

  contentArea->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
  contentArea->setFrameStyle(QFrame::NoFrame);

  // start out collapsed
  contentArea->setMaximumHeight(0);
  contentArea->setMinimumHeight(0);

  // let the entire widget grow and shrink with its content
  toggleAnimation->addAnimation(new QPropertyAnimation(this, "maximumHeight"));
  toggleAnimation->addAnimation(new QPropertyAnimation(this, "minimumHeight"));
  toggleAnimation->addAnimation(new QPropertyAnimation(contentArea, "maximumHeight"));

  mainLayout->setVerticalSpacing(0);
  mainLayout->setContentsMargins(0, 0, 0, 0);

  int row = 0;
  mainLayout->addWidget(toggleButton, row, 0, 1, 1, Qt::AlignLeft);
  mainLayout->addWidget(headerLine, row++, 2, 1, 1);
  mainLayout->addWidget(contentArea, row, 0, 1, 3);
  setLayout(mainLayout);

  connect(toggleButton, &QToolButton::toggled, this, &AutoCollapsibleSection::toggle);
  connect(toggleAnimation, &QParallelAnimationGroup::finished, [this] ()
  {
    if (fnResize) fnResize();
    emit resized();
  });
}

QGridLayout * AutoCollapsibleSection::start(const QString & title)
{
  setTitle(title);
  return contentAreaLayout;
}

void AutoCollapsibleSection::finish(int springRow, int springCol, std::function<void()> fnResize, bool expand)
{
  if (springRow >= 0 && springCol >= 0) {
    QSpacerItem * spacer = new QSpacerItem(0, 0, QSizePolicy::Expanding, QSizePolicy::Minimum );
    contentAreaLayout->addItem(spacer, springRow, springCol);
  }

  // attach after constructed for better sizing
  setContentLayout(*contentAreaLayout);
  setBindResize(fnResize);
  toggleButton->setChecked(expand);
}

void AutoCollapsibleSection::setAnimationDuration(const int duration)
{
  animationDuration = duration;
}

void AutoCollapsibleSection::setBindResize(std::function<void()> fn)
{
  fnResize = std::move(fn);
}

void AutoCollapsibleSection::setContentLayout(QLayout & contentLayout)
{
  delete contentArea->layout();
  contentArea->setLayout(&contentLayout);
  collapsedHeight = sizeHint().height() - contentArea->maximumHeight();
  updateHeights();
}

void AutoCollapsibleSection::setTitle(const QString & title)
{
  toggleButton->setText(title);
}

void AutoCollapsibleSection::toggle(bool expanded)
{
  toggleButton->setArrowType(expanded ? Qt::ArrowType::DownArrow :
                                        Qt::ArrowType::RightArrow);
  toggleAnimation->setDirection(expanded ? QAbstractAnimation::Forward :
                                           QAbstractAnimation::Backward);
  toggleAnimation->start();
  isExpanded = expanded;
}

void AutoCollapsibleSection::updateHeights()
{
  int contentHeight = contentArea->layout()->sizeHint().height();

  for (int i = 0; i < toggleAnimation->animationCount() - 1; ++i) {
    QPropertyAnimation* SectionAnimation = static_cast<QPropertyAnimation *>
      (toggleAnimation->animationAt(i));
    SectionAnimation->setDuration(animationDuration);
    SectionAnimation->setStartValue(collapsedHeight);
    SectionAnimation->setEndValue(collapsedHeight + contentHeight);
  }

  QPropertyAnimation* contentAnimation = static_cast<QPropertyAnimation *>
    (toggleAnimation->animationAt(toggleAnimation->animationCount() - 1));
  contentAnimation->setDuration(animationDuration);
  contentAnimation->setStartValue(0);
  contentAnimation->setEndValue(contentHeight);

  toggleAnimation->setDirection(isExpanded ? QAbstractAnimation::Forward :
                                             QAbstractAnimation::Backward);
  toggleAnimation->start();
}