//  ************************************************************************************************
//
//  BornAgain: simulate and fit reflection and scattering
//
//! @file      GUI/View/SampleDesigner/LayerForm.cpp
//! @brief     Implements class LayerForm
//!
//! @homepage  http://www.bornagainproject.org
//! @license   GNU General Public License v3 or higher (see COPYING)
//! @copyright Forschungszentrum Jülich GmbH 2021
//! @authors   Scientific Computing Group at MLZ (see CITATION, AUTHORS)
//
//  ************************************************************************************************

#include "GUI/View/SampleDesigner/LayerForm.h"
#include "GUI/Model/Sample/LayerItem.h"
#include "GUI/Model/Sample/MaterialItem.h"
#include "GUI/Model/Sample/MaterialModel.h"
#include "GUI/Model/Sample/SampleItem.h"
#include "GUI/Support/Util/ActionFactory.h"
#include "GUI/Support/Util/WidgetMoverButton.h"
#include "GUI/View/Numeric/NumWidgetUtils.h"
#include "GUI/View/SampleDesigner/FormLayouter.h"
#include "GUI/View/SampleDesigner/MaterialInplaceForm.h"
#include "GUI/View/SampleDesigner/ParticleLayoutForm.h"
#include "GUI/View/Tool/GroupBoxCollapser.h"
#include <QLineEdit>
#include <QMenu>
#include <QPushButton>
#include <memory>

LayerForm::LayerForm(QWidget* parent, LayerItem* layer, SampleEditorController* ec)
    : QGroupBox(parent)
    , m_layer(layer)
    , m_ec(ec)
{
    setTitle(m_layer->layerName());
    m_layouter = std::make_unique<FormLayouter>(this, ec);
    m_layouter->setContentsMargins(6, 6, 0, 6);
    m_collapser = GroupBoxCollapser::installIntoGroupBox(this, false);
    m_collapser->setExpanded(layer->isExpandLayer());
    connect(m_collapser, &GroupBoxCollapser::toggled, this,
            [layer](bool b) { layer->setExpandLayer(b); });

    m_removeAction =
        ActionFactory::createRemoveAction(this, "layer", [=] { ec->removeLayerItem(layer); });

    auto* chooseColorAction = new QAction(this);
    chooseColorAction->setText("Choose color");
    chooseColorAction->setIcon(QIcon(":/images/palette.svg"));
    chooseColorAction->setIconText("Choose color");
    chooseColorAction->setToolTip("Choose a color for this layer");
    auto* menu = new QMenu(this);
    chooseColorAction->setMenu(menu);

    for (const auto& col : LayerEditorUtils::predefinedLayerColors()) {
        QPixmap p(64, 64);
        p.fill(col);
        auto* ca = menu->addAction(QIcon(p), "");
        connect(ca, &QAction::triggered, [=]() {
            layer->setColor(col);
            updateColor();
        });
    }

    m_moveButton = new WidgetMoverButton(this, this, 1);
    m_moveButton->setToolTip("Move layer up/down");
    connect(m_moveButton, &WidgetMoverButton::startingToMove, ec,
            &SampleEditorController::onStartingToMoveLayer);
    connect(m_moveButton, &WidgetMoverButton::finishedMoving, ec,
            &SampleEditorController::onStoppedToMoveLayer);

    auto* showInRealspaceAction = ActionFactory::createShowInRealspaceAction(
        this, "layer", [=] { m_ec->requestViewInRealspace(layer); });

    m_collapser->addAction(showInRealspaceAction);
    m_collapser->addAction(chooseColorAction);
    m_collapser->addAction(m_removeAction);
    m_collapser->addWidget(m_moveButton);
    m_structureEditingWidgets << m_moveButton;

    QColor bckgroundCol = m_layer->color();
    setStyleSheet("QGroupBox {background-color: " + bckgroundCol.name(QColor::HexRgb) + "}");

    m_layouter->addRow("Material:", new MaterialInplaceForm(this, layer, ec));
    m_thicknessRow = m_layouter->addValue(m_layer->thickness());

    m_layouter->addRow("Number of slices:",
                       GUI::Util::createIntSpinbox([=] { return m_layer->numSlices(); },
                                                   [=](int v) {
                                                       m_layer->setNumSlices(v);
                                                       emit m_ec->modified();
                                                   },
                                                   RealLimits::lowerLimited(1),
                                                   "Number of horizontal slices.\n"
                                                   "Used for Average Layer Material calculations \n"
                                                   "when corresponding simulation option is set."));

    m_roughnessRow = m_layouter->addSelection(m_layer->roughnessSelection());

    // -- layouts
    for (auto* layout : layer->layoutItems())
        m_layouter->addRow(new ParticleLayoutForm(this, layout, ec));

    // -- Button for adding a new layout
    auto* btn = new QPushButton("Add particle layout", this);
    connect(btn, &QPushButton::clicked, [=] { ec->addLayoutItem(this); });
    m_structureEditingWidgets << btn;
    m_layouter->addStructureEditingRow(btn);

    // listen to changes in materials to update the title (contains the material name). Necessary
    // to reflect e.g. a name change done in the material editor.
    connect(ec->materialModel(), &MaterialModel::materialChanged, this, &LayerForm::updateTitle);

    updateLayerPositionDependentElements();
}

void LayerForm::enableStructureEditing(bool b)
{
    m_removeAction->setVisible(b);

    for (auto* w : m_structureEditingWidgets)
        w->setVisible(b);

    if (b && m_ec->sampleItem()->layerItems().size() < 2)
        m_moveButton->setVisible(false);
}

void LayerForm::updateColor()
{
    QColor bckgroundCol = m_layer->color();
    setStyleSheet("QGroupBox {background-color: " + bckgroundCol.name(QColor::HexRgb) + "}");
}

void LayerForm::updateTitle()
{
    int i = m_ec->sampleItem()->layerItems().indexOf(m_layer);
    m_collapser->setTitle("Layer " + QString::number(i)
                          + "     Material: " + m_layer->materialName());
}

void LayerForm::expand()
{
    m_collapser->setExpanded(true);
}

void LayerForm::updateLayerPositionDependentElements()
{
    if (m_roughnessRow == -1)
        return;

    updateTitle();

    const auto* sample = m_ec->sampleItem();
    const bool isFirstLayer = sample->layerItems().first() == m_layer;
    const bool isLastLayer = sample->layerItems().last() == m_layer;
    const bool thicknessIsSemiInfinite =
        (isFirstLayer || isLastLayer) && (sample->layerItems().size() != 1);
    const bool thicknessIsInfinite = sample->layerItems().size() == 1;

    m_layouter->setRowVisible(m_roughnessRow, !isFirstLayer);

    if (m_thicknessRow == -1)
        return;
    QWidget* w = m_layouter->layout()->itemAt(m_thicknessRow, QFormLayout::FieldRole)->widget();
    if (thicknessIsSemiInfinite || thicknessIsInfinite) {
        auto* info = qobject_cast<QLineEdit*>(w);
        if (info == nullptr) {
            m_layouter->removeRow(m_thicknessRow);
            info = new QLineEdit(this);
            info->setEnabled(false);
            info->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
            m_layouter->insertRow(m_thicknessRow, m_layer->thickness().label(), info);
        }
        info->setText(thicknessIsSemiInfinite ? "Semi-infinite" : "Infinite");
    } else if (!thicknessIsSemiInfinite && !thicknessIsInfinite
               && (qobject_cast<QLineEdit*>(w) != nullptr)) {
        m_layouter->removeRow(m_thicknessRow);
        m_layouter->insertValue(m_thicknessRow, m_layer->thickness());
    }

    if (m_ec->sampleItem()->layerItems().size() < 2)
        m_moveButton->setVisible(false);
}

void LayerForm::onLayoutAdded(ParticleLayoutItem* newLayoutItem)
{
    int index = m_layer->layoutItems().indexOf(newLayoutItem);
    const int rowInLayout =
        m_layouter->layout()->rowCount() - m_layer->layoutItems().size() + index;

    m_layouter->insertRow(rowInLayout, new ParticleLayoutForm(this, newLayoutItem, m_ec));
}

void LayerForm::onAboutToRemoveLayout(ParticleLayoutItem* layoutItem)
{
    int index = m_layer->layoutItems().indexOf(layoutItem);
    const int rowInLayout =
        m_layouter->layout()->rowCount() - m_layer->layoutItems().size() - 1 + index; // -1: btn

    m_layouter->removeRow(rowInLayout);
}

LayerItem* LayerForm::layerItem() const
{
    return m_layer;
}