//========================================================================

//

// SplashXPathScanner.h

//

//========================================================================

//========================================================================

//

// Modified under the Poppler project - http://poppler.freedesktop.org

//

// All changes made under the Poppler project to this file are licensed

// under GPL version 2 or later

//

// Copyright (C) 2013, 2014, 2021 Thomas Freitag <Thomas.Freitag@alfa.de>

// Copyright (C) 2018, 2021, 2025 Albert Astals Cid <aacid@kde.org>

// Copyright (C) 2018, 2025 Stefan Brüns <stefan.bruens@rwth-aachen.de>

//

// To see a description of the changes please see the Changelog file that

// came with your tarball or type make ChangeLog if you are building from git

//

//========================================================================

#ifndef SPLASHXPATHSCANNER_H

#define SPLASHXPATHSCANNER_H

#include <poppler-config.h>

#if USE_BOOST_HEADERS

#    include <boost/container/small_vector.hpp>

#endif

#include <vector>

class SplashXPath;

class SplashBitmap;

struct SplashIntersect

{

    int x0, x1; // intersection of segment with [y, y+1)

    int count; // EO/NZWN counter increment

};

//------------------------------------------------------------------------

// SplashXPathScanner

//------------------------------------------------------------------------

class SplashXPathScanner

{

public:

    // Create a new SplashXPathScanner object.  <xPathA> must be sorted.

    SplashXPathScanner(const SplashXPath &xPath, bool eoA, int clipYMin, int clipYMax);

    ~SplashXPathScanner();

    SplashXPathScanner(const SplashXPathScanner &) = delete;

    SplashXPathScanner &operator=(const SplashXPathScanner &) = delete;

    // Return the path's bounding box.

    void getBBox(int *xMinA, int *yMinA, int *xMaxA, int *yMaxA) const

    {

        *xMinA = xMin;

        *yMinA = yMin;

        *xMaxA = xMax;

        *yMaxA = yMax;

    }

    // Return the path's bounding box.

    void getBBoxAA(int *xMinA, int *yMinA, int *xMaxA, int *yMaxA) const;

    // Returns true if (<x>,<y>) is inside the path.

    bool test(int x, int y) const;

    // Returns true if the entire span ([<x0>,<x1>], <y>) is inside the

    // path.

    bool testSpan(int x0, int x1, int y) const;

    // Renders one anti-aliased line into <aaBuf>.  Returns the min and

    // max x coordinates with non-zero pixels in <x0> and <x1>.

    void renderAALine(SplashBitmap *aaBuf, int *x0, int *x1, int y, bool adjustVertLine = false) const;

    // Clips an anti-aliased line by setting pixels to zero.  On entry,

    // all non-zero pixels are between <x0> and <x1>.  This function

    // will update <x0> and <x1>.

    void clipAALine(SplashBitmap *aaBuf, const int *x0, const int *x1, int y) const;

private:

    void computeIntersections(const SplashXPath &xPath);

    void addIntersection(double segYMin, int y, int x0, int x1, int count);

    const bool eo;

    int xMin = 1, yMin = 1, xMax = 0, yMax = 0;

#if USE_BOOST_HEADERS

    using IntersectionLine = boost::container::small_vector<SplashIntersect, 4>;

#else

    using IntersectionLine = std::vector<SplashIntersect>;

#endif

    std::vector<IntersectionLine> allIntersections;

    friend class SplashXPathScanIterator;

};

class SplashXPathScanIterator

{

public:

    SplashXPathScanIterator(const SplashXPathScanner &scanner, int y);

    // Returns the next span inside the path at the current y position

    // Returns false if there are no more spans.

    bool getNextSpan(int *x0, int *x1);

private:

#if USE_BOOST_HEADERS

    using IntersectionLine = boost::container::small_vector<SplashIntersect, 4>;

#else

    using IntersectionLine = std::vector<SplashIntersect>;

#endif

    const IntersectionLine &line;

    size_t interIdx = 0; // current index into <line>

    int interCount = 0; // current EO/NZWN counter

    const bool eo;

};

#endif