#include "pageindicator.h"
#include <QPainter>
#include <QMouseEvent>

PageIndicator::PageIndicator(int pageCount, QWidget *parent)
    : QWidget(parent), m_pageCount(pageCount), m_currentPage(0), m_dotSize(8), m_selectedDotSize(10), m_dotSpacing(14), m_dotColor(QColor(255, 255, 255, 120)), m_selectedColor(QColor(255, 255, 255, 255))
{
  setCursor(Qt::PointingHandCursor);
  setAttribute(Qt::WA_TranslucentBackground);
}

PageIndicator::~PageIndicator()
{
}

void PageIndicator::setPageCount(int count)
{
  if (count != m_pageCount)
  {
    m_pageCount = count;
    if (m_currentPage >= m_pageCount)
    {
      m_currentPage = m_pageCount - 1;
    }
    update();
  }
}

void PageIndicator::setCurrentPage(int page)
{
  if (page >= 0 && page < m_pageCount && page != m_currentPage)
  {
    m_currentPage = page;
    update();
  }
}

void PageIndicator::paintEvent(QPaintEvent *event)
{
  Q_UNUSED(event)

  QPainter painter(this);
  painter.setRenderHint(QPainter::Antialiasing);

  // 计算总宽度
  int totalWidth = 0;
  for (int i = 0; i < m_pageCount; ++i)
  {
    int dotSize = (i == m_currentPage) ? m_selectedDotSize : m_dotSize;
    totalWidth += dotSize;
    if (i < m_pageCount - 1)
    {
      totalWidth += m_dotSpacing;
    }
  }

  // 计算起始位置（居中）
  int startX = (width() - totalWidth) / 2;
  int centerY = height() / 2;

  // 绘制指示点
  int x = startX;
  for (int i = 0; i < m_pageCount; ++i)
  {
    bool isSelected = (i == m_currentPage);
    int dotSize = isSelected ? m_selectedDotSize : m_dotSize;
    QColor color = isSelected ? m_selectedColor : m_dotColor;

    painter.setPen(Qt::NoPen);
    painter.setBrush(color);

    int y = centerY - dotSize / 2;
    painter.drawEllipse(x, y, dotSize, dotSize);

    x += dotSize + m_dotSpacing;
  }
}

void PageIndicator::mousePressEvent(QMouseEvent *event)
{
  // 计算点击位置对应的页面
  int totalWidth = 0;
  for (int i = 0; i < m_pageCount; ++i)
  {
    int dotSize = (i == m_currentPage) ? m_selectedDotSize : m_dotSize;
    totalWidth += dotSize;
    if (i < m_pageCount - 1)
    {
      totalWidth += m_dotSpacing;
    }
  }

  int startX = (width() - totalWidth) / 2;
  int x = startX;

  for (int i = 0; i < m_pageCount; ++i)
  {
    int dotSize = (i == m_currentPage) ? m_selectedDotSize : m_dotSize;

    // 扩大点击区域
    QRect hitRect(x - 8, 0, dotSize + 16, height());

    if (hitRect.contains(event->pos()))
    {
      if (i != m_currentPage)
      {
        emit pageClicked(i);
      }
      break;
    }

    x += dotSize + m_dotSpacing;
  }

  QWidget::mousePressEvent(event);
}