#include "verifycodewidget.h"

#include <QPainter>
#include <QPen>
#include <QFont>
#include <QChar>
#include <QPaintEvent>
#include <QMouseEvent>
#include <QColor>
#include <QString>

#include "model/data.h"

VerifyCodeWidget::VerifyCodeWidget(QWidget *parent)
	: QWidget(parent),
    randomGenerator(model::getTime())
{
	verifyCode = generateVerifyCode();
}

QString VerifyCodeWidget::generateVerifyCode()
{
	QString code;
	for (int i = 0; i < 4; i++) {
		//每次循环生成一个字符
		int init = 'A';
		init += randomGenerator.generate() % 26;
		code += static_cast<QChar>(init);
	}
	return code;
}

void VerifyCodeWidget::refreshVerifyCode()
{
    verifyCode = generateVerifyCode();
    // 通过 update 就可以起到 "刷新界面" , 本身就是触发 paintEvent
    this->update();
}

bool VerifyCodeWidget::checkVerifyCode(const QString& verifyCode)
{
    //此处比较验证码需要忽略大小写
    return this->verifyCode.compare(verifyCode, Qt::CaseInsensitive) == 0;
}

void VerifyCodeWidget::paintEvent(QPaintEvent* event)
{
    (void)event;
    const int width = 180;
    const int height = 80;

    QPainter painter(this);
    QPen pen;
    QFont font("楷体", 25, QFont::Bold, true);
    painter.setFont(font);

    // 画点: 添加随机噪点
    for (int i = 0; i < 100; i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 256, randomGenerator.generate() % 256, randomGenerator.generate() % 256));
        painter.setPen(pen);
        painter.drawPoint(randomGenerator.generate() % width, randomGenerator.generate() % height);
    }

    // 画线: 添加随机干扰线
    for (int i = 0; i < 5; i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 256, randomGenerator.generate() % 256, randomGenerator.generate() % 256));
        painter.setPen(pen);
        painter.drawLine(randomGenerator.generate() % width, randomGenerator.generate() % height,
            randomGenerator.generate() % width, randomGenerator.generate() % height);
    }

    // 绘制验证码
    for (int i = 0; i < verifyCode.size(); i++)
    {
        // 随机字体大小
        int fontSize = 13 + randomGenerator.generate() % 16; // 20~35
        QFont font("楷体", fontSize, QFont::Bold, true);
        painter.setFont(font);

        // 随机旋转角度（-30~30度）
        int angle = (randomGenerator.generate() % 61) - 30;

        // 随机颜色
        pen = QPen(QColor(randomGenerator.generate() % 255, randomGenerator.generate() % 255, randomGenerator.generate() % 255));
        painter.setPen(pen);

        // 保存当前状态
        painter.save();

        // 计算字符中心点
        int x = 5 + 22 * i;
        int y = 10;
        int w = 30, h = 30;
        QPoint center(x + w / 2, y + h / 2);

        // 平移到中心，旋转，再平移回去
        painter.translate(center);
        painter.rotate(angle);
        painter.translate(-center);

        // 绘制字符
        painter.drawText(x, y, w, h, Qt::AlignCenter, QString(verifyCode[i]));

        // 恢复状态
        painter.restore();
    }

    // 绘制验证码
    /*for (int i = 0; i < verifyCode.size(); i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 255, randomGenerator.generate() % 255, randomGenerator.generate() % 255));
        painter.setPen(pen);
        painter.drawText(5 + 22 * i, randomGenerator.generate() % 10, 30, 30, Qt::AlignCenter, QString(verifyCode[i]));
    }*/

}

void VerifyCodeWidget::mousePressEvent(QMouseEvent* event)
{
    (void)event;
    this->refreshVerifyCode();
}