#include "RecipeLineRow.h"

#include <QHBoxLayout>
#include <QLabel>
#include <QLayoutItem>
#include <QPixmap>

#include "BuildingIconCache.h"
#include "ItemIconCache.h"

namespace
{

// Size the items' colored squares and the building's chip are drawn at on a line, in
// device-independent pixels. Larger than the artwork they carry, which the square
// insets (REQ-UI-ITEM-ICON).
const int kIconSizePx = 18;

// Adds a freshly built label to the line and shows it.
//
// The show is what makes it count: a widget created under an already-visible parent
// starts hidden, and a layout treats a hidden item as empty, so an unshown label would
// add nothing to the size hint the surrounding widget measures itself against as soon
// as this returns.
void addAndShow(QHBoxLayout* layout, QLabel* label)
{
    layout->addWidget(label);
    label->show();
}

}  // namespace


RecipeLineRow::RecipeLineRow(ItemIconCache* itemIcons, BuildingIconCache* buildingIcons,
                             QWidget* parent)
    : QWidget(parent)
    , m_itemIcons(itemIcons)
    , m_buildingIcons(buildingIcons)
{
    m_layout = new QHBoxLayout(this);
    m_layout->setContentsMargins(0, 0, 0, 0);
    m_layout->setSpacing(4);

    hide();
}

void RecipeLineRow::setLine(const Spec& spec)
{
    if (spec.isEmpty())
    {
        // Forgotten as well as hidden, so re-selecting the same recipe later is seen as
        // a change and shows the row again.
        m_spec = Spec();
        hide();
        return;
    }
    if (spec == m_spec)
    {
        return;
    }

    m_spec = spec;
    rebuild(spec);
    show();
}

void RecipeLineRow::rebuild(const Spec& spec)
{
    while (QLayoutItem* item = m_layout->takeAt(0))
    {
        if (item->widget())
        {
            item->widget()->deleteLater();
        }
        delete item;
    }

    // The building the recipe runs in, where the line has to distinguish one producer
    // from another (REQ-UI-ITEM-TOOLTIP). A building with no chip file leaves the icon
    // off, as everywhere else (REQ-UI-BUILD-ICON).
    if (spec.building.has_value() && m_buildingIcons != nullptr)
    {
        const QPixmap chip =
            m_buildingIcons->getChip(buildingTypeId(*spec.building), kIconSizePx);
        if (!chip.isNull())
        {
            QLabel* chipLabel = new QLabel(this);
            chipLabel->setPixmap(chip);
            addAndShow(m_layout, chipLabel);
        }
    }
    if (!spec.name.isEmpty())
    {
        addAndShow(m_layout, new QLabel(spec.name, this));
    }

    addAmounts(spec.inputs);
    if (!spec.inputs.empty() && !spec.outputs.empty())
    {
        const QChar rightArrow(0x2192);  // U+2192 RIGHTWARDS ARROW
        addAndShow(m_layout, new QLabel(QString(rightArrow), this));
    }
    addAmounts(spec.outputs);

    if (spec.durationSeconds.has_value() && *spec.durationSeconds > 0.0)
    {
        const QChar middleDot(0x00B7);  // U+00B7 MIDDLE DOT
        const QString time = spec.durationIsAddition
            ? tr("+%1 s").arg(*spec.durationSeconds, 0, 'f', 1)
            : tr("%1 s").arg(*spec.durationSeconds, 0, 'f', 1);
        addAndShow(m_layout, new QLabel(
            QStringLiteral("%1 %2").arg(middleDot).arg(time), this));
    }
    m_layout->addStretch(1);
}

void RecipeLineRow::addAmounts(const std::vector<Amount>& amounts)
{
    for (const Amount& entry : amounts)
    {
        // The item's icon on its colored square (REQ-UI-ITEM-ICON). A missing icon file
        // is not an error: the square stands alone then, and only an item with no square
        // either falls back to its id in text.
        const QPixmap icon = (m_itemIcons != nullptr)
            ? m_itemIcons->getSquarePixmap(entry.itemId, kIconSizePx)
            : QPixmap();
        if (!icon.isNull())
        {
            QLabel* iconLabel = new QLabel(this);
            iconLabel->setPixmap(icon);
            addAndShow(m_layout, iconLabel);
        }
        else
        {
            addAndShow(m_layout,
                       new QLabel(QString::fromStdString(entry.itemId), this));
        }
        addAndShow(m_layout, new QLabel(QString::number(entry.amount), this));
    }
}