#include "citylist.h"
#include "settings.h"
#include "pixmaploader.h"
#include <QPainter>
#include <cmath>
#include <QParallelAnimationGroup>
#include <QPropertyAnimation>

#define LIST_TOP_PIXMAP             (PixmapLoader::getPic("list_top"))

#define ITEM_BACKGROUND             (PixmapLoader::getPic("list_item_bg"))
#define SELECTED_ITEM_BACKGROUND    (PixmapLoader::getPic("list_item_selected_bg"))

#define ITEM_BUTTON_PIXMAP          (PixmapLoader::getPic("button_list_delete"))
#define ITEM_BUTTON_LEFT            (Settings::scaleWidth(406.0))

#define ITEM_CHECK_PIXMAP           (PixmapLoader::getPic("list_check"))
#define ITEM_CHECK_LEFT             (Settings::scaleWidth(10.0))

#define TEXT_LEFT                   (2 * ITEM_CHECK_LEFT + ITEM_CHECK_PIXMAP.width())

#define CITY_NAME_FONT_SIZE         (Settings::scaleHeight(50.0))

static const int maxVisibleItems = 6;
static const int minListCount = 3;

static inline qreal getCenterVerticalPos(QGraphicsItem *parent, QGraphicsItem *item)
{
    const qreal top = (parent->boundingRect().height() - item->boundingRect().height()) / 2;
    return top - parent->boundingRect().top() - item->boundingRect().top();
}

static inline qreal getCenterVerticalPos(QGraphicsItem *item)
{
    return getCenterVerticalPos(item->parentItem(), item);
}

// CityListScrollBox

#ifdef QT_ARCH_ARM
static const int acceleration_factor = 12;
#else
static const int acceleration_factor = 64;
#endif


static const int max_gesture_time_ms = 500;
static const qreal degrees = 30.0;
static const qreal limit_angle_tg = tan(degrees * 3.141592 / 180.0);
static const qreal min_gesture_length = 100.0;

CityListScrollBox::CityListScrollBox(QGraphicsItem *content, QGraphicsItem *parent)
    : GestureBox(parent)
    , m_content(content)
    , m_scroll(new ScrollBar(this))
{
    setFlag(QGraphicsItem::ItemClipsChildrenToShape, true);
    if (m_content)
        m_content->setParentItem(this);

    m_scroll->setPos(Settings::scaleWidth(460.0), Settings::scaleHeight(32.5));

    m_content->setZValue(0.0);
    m_scroll->setZValue(1.0);
}

void CityListScrollBox::gestureMousePress(QPointF pos, bool &startGesture, bool &acceptClick)
{
    Q_UNUSED(pos);
    startGesture = true;
    acceptClick = !m_ticker.isActive();
    if (m_ticker.isActive()) {
        m_ticker.stop();
        m_speed = 0.0;
    }
}

void CityListScrollBox::gestureStart(QPointF pos)
{
    m_startPoint = pos;
}

void CityListScrollBox::contentPositionUpdated()
{
    qreal height = boundingRect().height();
    qreal content = m_content->boundingRect().height();

    if (height < content) {
        qreal pos = content - height;
        pos = -m_content->pos().y() / pos;
        m_scroll->setValue(pos < 0.0 ? 0.0 : pos);
    } else
        if (m_content->pos().y() != 0.0) {
            m_content->setPos(0.0, 0.0);
            m_scroll->setValue(0.0);
        }

}

bool CityListScrollBox::move(QPointF movement)
{
    if (m_content && m_content->boundingRect().height() > boundingRect().height()) {

        qreal dist = movement.y();


        if (dist > 0 && m_content->pos().y() < 0) {
            qreal top = m_content->pos().y() + dist;
            m_content->setPos(m_content->pos().x(), top > 0 ? 0 : top);
            contentPositionUpdated();
            return true;
        }

        if (dist < 0) {
            qreal top = m_content->pos().y() + dist;
            if (top + m_content->boundingRect().height() >= boundingRect().height()) {
                m_content->setPos(m_content->pos().x(), top);
                contentPositionUpdated();
                return true;
            }
        }

    }
    return false;
}

void CityListScrollBox::gestureMove(QPointF pos, QPointF movement, QPointF speed)
{
    Q_UNUSED(pos);
    Q_UNUSED(speed);
    move(movement);
}

void CityListScrollBox::gestureEnd(QPointF pos, QPointF speed)
{
    qreal x = pos.x() - m_startPoint.x();
    qreal y = pos.y() - m_startPoint.y();
    if (fabs(x / y) > limit_angle_tg || fabs(y) < min_gesture_length)
        return;

    qreal topSpeed = Settings::scaleHeight(1500.0);
    m_acceleration = topSpeed / acceleration_factor;
    m_speed = qBound(-topSpeed, speed.y(), topSpeed);
    if (m_speed != 0) {
        m_time = QTime::currentTime();
        m_ticker.start(20, this);
    }
}

void CityListScrollBox::timerEvent(QTimerEvent *event)
{
    bool stopTimer = true;
    if (m_speed != 0.0) {
        QTime now(QTime::currentTime());
        qreal movement = m_speed * (qreal)m_time.msecsTo(now) / 1000.0;
        m_time = now;
        stopTimer = !move(QPointF(0, movement));
        if (!stopTimer) {
            m_speed = m_speed > 0.0 ? qMax(qreal(0.0), m_speed - m_acceleration)
                                    : qMin(qreal(0.0), m_speed + m_acceleration);
            stopTimer = m_speed == 0.0;
        }
    }
    if (stopTimer)
        m_ticker.stop();
    QObject::timerEvent(event);
}

// CityListText

CityListText::CityListText(const QString &text, QGraphicsItem *parent)
    : QGraphicsItem(parent)
    , m_painter(CITY_NAME_FONT_SIZE, Qt::white, text)
{
    setCacheMode(ItemCoordinateCache);
    m_painter.setPos(0.0, 0.0);
    m_painter.setMaxWidth(ITEM_BUTTON_LEFT - TEXT_LEFT);
}

QRectF CityListText::boundingRect() const
{
    return QRectF(0.0, 0.0, m_painter.width(), m_painter.height());
}

void CityListText::paint(QPainter *painter, const QStyleOptionGraphicsItem *opt, QWidget *widget)
{
    Q_UNUSED(opt);
    Q_UNUSED(widget);
    m_painter.paint(painter);
}

//  CityListItem

CityListItem::CityListItem(const ForecastData &data, CityContentList *list, bool deleteVisible)
    : ContentListItem(0)
    , m_height(ITEM_BACKGROUND.height())
    , m_data(data)
    , m_list(list)
    , m_background(new QGraphicsPixmapItem(ITEM_BACKGROUND, this))
    , m_check(new QGraphicsPixmapItem(ITEM_CHECK_PIXMAP, m_background))
    , m_delete(new PixmapButton(80.0, ITEM_BUTTON_PIXMAP, m_background))
    , m_text(new CityListText(m_data.cityName(), this))
{
    m_delete->setPos(ITEM_BUTTON_LEFT, getCenterVerticalPos(m_delete));
    m_delete->setVisible(deleteVisible);
    m_delete->setOpacity(deleteVisible ? 1.0 : 0.0);
    m_check->setPos(ITEM_CHECK_LEFT, getCenterVerticalPos(m_check));
    m_check->hide();
    m_text->setPos(TEXT_LEFT, getCenterVerticalPos(m_text));
    m_text->setCacheMode(ItemCoordinateCache);

    connect(m_delete, SIGNAL(clicked()), this, SLOT(removeFromList()));
}

void CityListItem::select(bool selected)
{
    m_background->setPixmap(selected ? SELECTED_ITEM_BACKGROUND : ITEM_BACKGROUND);
    m_check->setVisible(selected);
}

void CityListItem::removeFromList()
{
    if (!m_list->busy())
        m_list->removeItem(this);
}

qreal CityListItem::contentHeight() const
{
    return m_height;
}

QAbstractAnimation *CityListItem::getButtonAnimation(bool hide)
{
    return getFadeAnimation(m_delete, hide, 150);
}

QAbstractAnimation *CityListItem::getShowAnimation()
{
    return getFadeAnimation(this, false, 150);
}

QAbstractAnimation *CityListItem::getHideAnimation()
{
    return getFadeAnimation(this, true, 150);
}

template<class T>QAbstractAnimation *CityListItem::getFadeAnimation(T *target, bool hide, int msecs)
{
    target->setOpacity(hide ? 1.0 : 0.0);
    target->show();
    QPropertyAnimation* lResult = new QPropertyAnimation(target, "opacity");
    lResult->setEasingCurve(QEasingCurve::OutExpo);
    lResult->setStartValue(hide ? 1.0 : 0.0);
    lResult->setEndValue(hide ? 0.0 : 1.0);
    lResult->setDuration(msecs);
    if (hide)
        connect(lResult, SIGNAL(finished()), target, SLOT(doHide()));
    return lResult;
}

// CityContentList

CityContentList::CityContentList(QList<ForecastData> &contentList, QObject *holder)
    : ContentList(0)
    , m_holder(holder)
    , m_contentList(contentList)
{
    QList<ContentListItem*> items;
    foreach (const ForecastData &data, m_contentList)
        items.append(new CityListItem(data, this, m_contentList.count() > minListCount));
    appendItems(items);
}

void CityContentList::addForecast(const ForecastData &data)
{
    m_contentList.append(data);
    addItem(new CityListItem(data, this, m_contentList.count() > minListCount));
}

void CityContentList::select(const QString &selected)
{
    for (int i = 0; i < itemCount(); ++i) {
        CityListItem *item = static_cast<CityListItem*>(getItem(i));
        if (item)
            item->select(item->data().key() == selected);
    }
}

QAbstractAnimation *CityContentList::getInsertAnimation(int idx, qreal height)
{
    if (idx < 0 || idx > itemCount())
        return 0;

    QList<QAbstractAnimation*> list;

    if (m_holder && itemCount() < maxVisibleItems)
        list.append(getMoveAnimation(m_holder, -height));

    if (idx < itemCount()) {
        for (int i = idx; i < itemCount(); ++i)
            list.append(getItemMoveAnimation(i, height));
    }

    if (parentItem() && itemCount() >= maxVisibleItems) {
        qreal top = parentItem()->boundingRect().height() - boundingRect().height() - height;
        list.append(getMoveAnimation(this, top - pos().y()));

    }

    if (itemCount() == minListCount) {
        for (int i = 0; i < minListCount; ++i) {
            CityListItem *item = static_cast<CityListItem*>(getItem(i));
            if (item)
                list.append(item->getButtonAnimation(false));
        }
    }

    return createCompoundAnimation(list);
}

QAbstractAnimation *CityContentList::getRemoveAnimation(int idx)
{
    if (idx < 0 || idx >= itemCount())
        return 0;

    qreal offset = -getItem(idx)->contentHeight();
    QList<QAbstractAnimation*> list;

    if (m_holder && itemCount() <= maxVisibleItems)
        list.append(getMoveAnimation(m_holder, -offset));

    for (int i = idx + 1; i < itemCount(); ++i)
        list.append(getItemMoveAnimation(i, offset));

    qreal newHeight = boundingRect().height() - getItem(idx)->contentHeight();

    if (parentItem()) {
        if (newHeight < parentItem()->boundingRect().height()) {
            if (pos().y() != 0)
                list.append(getMoveAnimation(this, -pos().y()));
        } else {
            if (pos().y() + newHeight < parentItem()->boundingRect().bottom()) {
                qreal offset = parentItem()->boundingRect().bottom() - pos().y() - newHeight;
                list.append(getMoveAnimation(this, offset));
            }
        }
    }

    if (itemCount() == minListCount + 1) {
        for (int i = 0; i <= minListCount; ++i) {
            if (i != idx) {
                CityListItem *item = static_cast<CityListItem*>(getItem(i));
                if (item)
                    list.append(item->getButtonAnimation(true));

            }
        }
    }

    m_contentList.removeAt(idx);


    return createCompoundAnimation(list);
}

QAbstractAnimation *CityContentList::createCompoundAnimation(QList<QAbstractAnimation*> list)
{
    if (list.count() == 0)
        return 0;
    if (list.count() == 1)
        return list[0];
    QParallelAnimationGroup *result = new QParallelAnimationGroup();
    for (int i = 0; i < list.count(); ++i)
        result->addAnimation(list[i]);
    return result;

}

QAbstractAnimation *CityContentList::getMoveAnimation(QObject *object, qreal offset)
{
    if (!object)
        return 0;
    qreal itemTop = object->property(ITEM_TOP_PROPERTY_NAME).toReal();
    QPropertyAnimation* lResult = new QPropertyAnimation(object, ITEM_TOP_PROPERTY_NAME);

    lResult->setEasingCurve(QEasingCurve::OutExpo);
    lResult->setStartValue(itemTop);
    lResult->setEndValue(itemTop + offset);
    lResult->setDuration(150);
    return lResult;
}

QAbstractAnimation *CityContentList::getItemMoveAnimation(int idx, qreal offset)
{
    return getMoveAnimation(getItem(idx), offset);
}

// CityList

CityList::CityList(QList<ForecastData> &contentList, QGraphicsItem *parent)
    : QGraphicsItem(parent)
    , m_itemHeight(ITEM_BACKGROUND.height())
    , m_topHeight(LIST_TOP_PIXMAP.height())
    , m_boundingRect(getBoundingRect())
    , m_paintRect(getPaintRect())
    , m_top(new QGraphicsPixmapItem(LIST_TOP_PIXMAP, this))
    , m_list(new CityContentList(contentList, this))
    , m_scrollBox(new CityListScrollBox(m_list, this))
{
    m_top->setPos(-m_top->boundingRect().left(), -m_top->boundingRect().top());
    m_scrollBox->setRect(m_paintRect);
    m_list->setWidth(m_paintRect.width());
}

qreal CityList::initialTop() const
{
    int count = maxVisibleItems - m_list->itemCount();
    if (count <= 0)
        return 0;
    return count * m_itemHeight;
}

QRectF CityList::getBoundingRect()
{
    QRectF result(QPointF(0.0, 0.0), Settings::windowSize());
    result.setHeight(m_topHeight + maxVisibleItems * m_itemHeight);
    result.moveTo(0.0, 0.0);
    return result;
}

QRectF CityList::getPaintRect()
{
    QRectF result(QPointF(0.0, 0.0), Settings::windowSize());
    result.setHeight(maxVisibleItems * m_itemHeight);
    result.moveTo(0.0, m_topHeight);
    return result;
}

int CityList::loadImages()
{
    PixmapLoader::load("list_top");
    PixmapLoader::load("list_item_bg");
    PixmapLoader::load("list_item_selected_bg");
    PixmapLoader::load("button_list_delete");
    PixmapLoader::load("list_check");
    return 5;
}

void CityList::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
    Q_UNUSED(event);
}

QRectF CityList::boundingRect () const
{
    return m_boundingRect;
}

void CityList::paint(QPainter *painter,
                               const QStyleOptionGraphicsItem *opt, QWidget *widget)
{
    Q_UNUSED(opt);
    Q_UNUSED(widget);
    painter->fillRect(m_paintRect, QColor(7, 18, 23, 255));
}