#include "ImageApplyAutoCrop.h"
#include "ImageProcess_Public.h"

CImageApplyAutoCrop::CImageApplyAutoCrop()
	: m_isCrop(false)
	, m_isDesaskew(false)
	, m_isFillBlank(false)
	, m_isConvexHull(true)
	, m_isFillColor(false)
	, m_threshold(40)
	, m_noise(2)
	, m_indent(5)
{
}

CImageApplyAutoCrop::CImageApplyAutoCrop(bool isCrop, bool isDesaskew, bool isFillBlank, const cv::Size& fixedSize, bool isConvex, bool isFillColor, double threshold, int noise, int indent)
	: m_isCrop(isCrop)
	, m_isDesaskew(isDesaskew)
	, m_isFillBlank(isFillBlank)
	, m_isConvexHull(isConvex)
	, m_isFillColor(isFillColor)
	, m_threshold(threshold)
	, m_noise(noise)
	, m_indent(indent)
	, m_fixedSize(fixedSize)
{
}

CImageApplyAutoCrop::~CImageApplyAutoCrop()
{
}

void CImageApplyAutoCrop::apply(cv::Mat& pDib, int side)
{
	(void)side;
	if (pDib.empty()) return;
	if (!m_isCrop && !m_isDesaskew && !m_isFillBlank && m_fixedSize.empty()) return;

	cv::Mat src = pDib;
	cv::Mat thre;
	cv::Mat dst;
	hg::threshold_Mat(src, thre, m_threshold);

	if (m_noise > 0)
	{
		cv::Mat element = getStructuringElement(cv::MORPH_RECT, cv::Size(m_noise, m_noise));
		cv::morphologyEx(thre, thre, cv::MORPH_OPEN, element);
	}
	std::vector<cv::Vec4i> hierarchy;
	std::vector<std::vector<cv::Point>> contours;

	hg::findContours(thre, contours, hierarchy, cv::RETR_EXTERNAL);
	m_maxContour = hg::getMaxContour(contours, hierarchy);

	if (m_maxContour.size() == 0)
	{
		thre.release();
		return;
	}
	thre.release();
	dst.release();

	cv::RotatedRect rect = hg::getBoundingRect(m_maxContour);
	cv::Rect boudingRect = cv::boundingRect(m_maxContour);
	boudingRect.x -= 1;
	boudingRect.y -= 1;
	boudingRect.width += 2;
	boudingRect.height += 2;

	if (m_isDesaskew && rect.angle != 0)
	{
		cv::Point2f srcTri[4];
		cv::Point2f dstTri[3];
		rect.points(srcTri);

		dstTri[0] = cv::Point2f(0, rect.size.height - 1);
		dstTri[1] = cv::Point2f(0, 0);
		dstTri[2] = cv::Point2f(rect.size.width - 1, 0);
		cv::Mat warp_mat;
		warp_mat = cv::getAffineTransform(srcTri, dstTri);
		cv::warpAffine(src, dst, warp_mat, rect.size);
	}
	else
		dst = src(boudingRect & cv::Rect(0, 0, src.cols, src.rows));

	m_maxContour.clear();
	m_maxContour.push_back(cv::Point(-1, dst.rows));
	m_maxContour.push_back(cv::Point(-1, -1));
	m_maxContour.push_back(cv::Point(dst.cols, -1));
	m_maxContour.push_back(cv::Point(dst.cols, dst.rows));

	if (m_isFillBlank)
	{
		cv::Mat thre_dst;
		hg::threshold_Mat(dst, thre_dst, m_threshold);

		if (m_indent > 0)
		{
			std::vector<cv::Point> rectEdge{ cv::Point(0, 0) ,cv::Point(thre_dst.cols - 1, 0),
				cv::Point(thre_dst.cols - 1, thre_dst.rows - 1), cv::Point(0, thre_dst.rows - 1) };
			std::vector<std::vector<cv::Point>> rectEdges{ rectEdge };
			cv::drawContours(thre_dst, rectEdges, 0, cv::Scalar::all(0));
			cv::Mat element = cv::getStructuringElement(cv::MorphShapes::MORPH_RECT, cv::Size(m_indent*2, m_indent*2));
			cv::erode(thre_dst, thre_dst, element, cv::Point(-1, -1), 1);
		}
		hierarchy.clear();
		contours.clear();
		m_maxContour.clear();

		hg::findContours(thre_dst, contours, hierarchy, cv::RETR_EXTERNAL);
		if (m_isConvexHull)
		{
			m_maxContour = hg::getMaxContour(contours, hierarchy);
			hg::convexHull(m_maxContour, m_maxContour);
			contours.clear();
			contours.push_back(m_maxContour);
		}

		contours.push_back(std::vector<cv::Point>());
		contours[contours.size() - 1].push_back(cv::Point(-1, dst.rows - 1));
		contours[contours.size() - 1].push_back(cv::Point(-1, -1));
		contours[contours.size() - 1].push_back(cv::Point(dst.cols, -1));
		contours[contours.size() - 1].push_back(cv::Point(dst.cols, dst.rows));

		hg::fillPolys(dst, contours, m_isFillColor ? getBackGroudColor(pDib, rect.size.area()) : cv::Scalar(255, 255, 255));
	}

	pDib.release();
	if (/*(m_isCrop && side == 0) || (side == 1 && m_fixedSize.width * m_fixedSize.height == 0)*/ m_isCrop)
		pDib = dst.clone();
	else
	{
		pDib = cv::Mat(m_fixedSize, dst.type(), m_isFillBlank ? cv::Scalar(255, 255, 255) : cv::Scalar(0, 0, 0));

		cv::Rect roi;
		roi.x = dst.cols > pDib.cols ? (dst.cols - pDib.cols) / 2 : 0;
		roi.width = cv::min(pDib.cols, dst.cols);
		roi.y = dst.rows > pDib.rows ? (dst.rows - pDib.rows) / 2 : 0;
		roi.height = cv::min(pDib.rows, dst.rows);
		cv::Rect rect((pDib.cols - roi.width) / 2, (pDib.rows - roi.height) / 2, roi.width, roi.height);

		for (cv::Point& p : m_maxContour)
			p += roi.tl();
		dst(roi).copyTo(pDib(rect));
	}
}

void CImageApplyAutoCrop::apply(std::vector<cv::Mat>& mats, bool isTwoSide)
{
	if (mats.empty()) return;
	if (!mats[0].empty()) {
		apply(mats[0], 0);
	}

	if (isTwoSide && mats.size() > 1)
	{
		cv::Size dSize = m_fixedSize;
		if (!mats[0].empty())
			m_fixedSize = mats[0].size();
		if (!mats[1].empty()) {
			apply(mats[1], 1);
		}

		if (!mats[0].empty())
			m_fixedSize = dSize;
	}
}

cv::Scalar CImageApplyAutoCrop::getBackGroudColor(const cv::Mat& image, int total)
{
	if (image.channels() == 3)
	{
		cv::Mat image_bgr[3];
		cv::split(image, image_bgr);

		uchar bgr[3];
		for (size_t i = 0; i < 3; i++)
			bgr[i] = getBackGroudChannelMean(image_bgr[i], total);
		return cv::Scalar(bgr[0], bgr[1], bgr[2]);
	}
	else
		return cv::Scalar::all(getBackGroudChannelMean(image, total));
}

uchar CImageApplyAutoCrop::getBackGroudChannelMean(const cv::Mat& gray, int total)
{
	cv::Mat image_clone;
	cv::resize(gray, image_clone, cv::Size(), 0.25, 0.25);

	int threnshold = total / 32;
	int channels[] = { 0 };
	int nHistSize[] = { 256 };
	float range[] = { 0, 256 };
	const float* fHistRanges[] = { range };
	cv::Mat hist;
	cv::calcHist(&image_clone, 1, channels, cv::Mat(), hist, 1, nHistSize, fHistRanges, true, false);

	int hist_array[256];
	for (int i = 0; i < 256; i++)
		hist_array[i] = hist.at<float>(i, 0);

	int length = 1;
	const int length_max = 255 - m_threshold;
	while (length < length_max)
	{
		for (size_t i = m_threshold + 1; i < 256 - length; i++)
		{
			int count = 0;
			uint pixSum = 0;
			for (size_t j = 0; j < length; j++)
			{
				count += hist_array[j + i];
				pixSum += hist_array[j + i] * (i + j);
			}

			if (count >= threnshold)
				return pixSum / count;
		}
		length++;
	}
	return 255;
}