/******************************************************************************

 *

 * File:        blobs.h

 * Description: Blob definition

 * Author:      Mark Seaman, OCR Technology

 *

 * (c) Copyright 1989, Hewlett-Packard Company.

 ** Licensed under the Apache License, Version 2.0 (the "License");

 ** you may not use this file except in compliance with the License.

 ** You may obtain a copy of the License at

 ** http://www.apache.org/licenses/LICENSE-2.0

 ** Unless required by applicable law or agreed to in writing, software

 ** distributed under the License is distributed on an "AS IS" BASIS,

 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 ** See the License for the specific language governing permissions and

 ** limitations under the License.

 *

 *****************************************************************************/

#ifndef BLOBS_H

#define BLOBS_H

#include "clst.h"       // for CLIST_ITERATOR, CLISTIZEH

#include "normalis.h"   // for DENORM

#include "points.h"     // for FCOORD, ICOORD

#include "rect.h"       // for TBOX

#include "scrollview.h" // for ScrollView, ScrollView::Color

#include <tesseract/publictypes.h> // for OcrEngineMode

#include "tesstypes.h" // for TDimension

struct Pix;

namespace tesseract {

class BLOCK;

class C_BLOB;

class C_OUTLINE;

class LLSQ;

class ROW;

class WERD;

/*----------------------------------------------------------------------

              T y p e s

----------------------------------------------------------------------*/

struct TPOINT {

  TPOINT() = default;

  TPOINT(TDimension vx, TDimension vy) : x(vx), y(vy) {}

  TPOINT(const ICOORD &ic) : x(ic.x()), y(ic.y()) {}

  void operator+=(const TPOINT &other) {

    x += other.x;

    y += other.y;

  }

  void operator/=(int divisor) {

    x /= divisor;

    y /= divisor;

  }

  bool operator==(const TPOINT &other) const {

    return x == other.x && y == other.y;

  }

  // Returns true when the two line segments cross each other.

  // (Moved from outlines.cpp).

  static bool IsCrossed(const TPOINT &a0, const TPOINT &a1, const TPOINT &b0, const TPOINT &b1);

  // Assign the difference from point p1 to point p2.

  void diff(const TPOINT &p1, const TPOINT &p2) {

    x = p1.x - p2.x;

    y = p1.y - p2.y;

  }

  // Return cross product.

  int cross(const TPOINT &other) const {

    return x * other.y - y * other.x;

  }

  // Return scalar or dot product.

  int dot(const TPOINT &other) const {

    return x * other.x + y * other.y;

  }

  // Calculate square of vector length.

  int length2() const {

    return x * x + y * y;

  }

  TDimension x = 0; // absolute x coord.

  TDimension y = 0; // absolute y coord.

};

using VECTOR = TPOINT; // structure for coordinates.

struct EDGEPT {

  EDGEPT() = default;

  EDGEPT(const EDGEPT &src) : next(nullptr), prev(nullptr) {

    CopyFrom(src);

  }

  EDGEPT &operator=(const EDGEPT &src) {

    CopyFrom(src);

    return *this;

  }

  // Copies the data elements, but leaves the pointers untouched.

  void CopyFrom(const EDGEPT &src) {

    pos = src.pos;

    vec = src.vec;

    is_hidden = src.is_hidden;

    runlength = src.runlength;

    dir = src.dir;

    fixed = src.fixed;

    src_outline = src.src_outline;

    start_step = src.start_step;

    step_count = src.step_count;

  }

  // Returns the squared distance between the points, with the x-component

  // weighted by x_factor.

  int WeightedDistance(const EDGEPT &other, int x_factor) const {

    int x_dist = pos.x - other.pos.x;

    int y_dist = pos.y - other.pos.y;

    return x_dist * x_dist * x_factor + y_dist * y_dist;

  }

  // Returns true if the positions are equal.

  bool EqualPos(const EDGEPT &other) const {

    return pos == other.pos;

  }

  // Returns the bounding box of the outline segment from *this to *end.

  // Ignores hidden edge flags.

  TBOX SegmentBox(const EDGEPT *end) const {

    TBOX box(pos.x, pos.y, pos.x, pos.y);

    const EDGEPT *pt = this;

    do {

      pt = pt->next;

      if (pt->pos.x < box.left()) {

        box.set_left(pt->pos.x);

      }

      if (pt->pos.x > box.right()) {

        box.set_right(pt->pos.x);

      }

      if (pt->pos.y < box.bottom()) {

        box.set_bottom(pt->pos.y);

      }

      if (pt->pos.y > box.top()) {

        box.set_top(pt->pos.y);

      }

    } while (pt != end && pt != this);

    return box;

  }

  // Returns the area of the outline segment from *this to *end.

  // Ignores hidden edge flags.

  int SegmentArea(const EDGEPT *end) const {

    int area = 0;

    const EDGEPT *pt = this->next;

    do {

      TPOINT origin_vec(pt->pos.x - pos.x, pt->pos.y - pos.y);

      area += origin_vec.cross(pt->vec);

      pt = pt->next;

    } while (pt != end && pt != this);

    return area;

  }

  // Returns true if the number of points in the outline segment from *this to

  // *end is less that min_points and false if we get back to *this first.

  // Ignores hidden edge flags.

  bool ShortNonCircularSegment(int min_points, const EDGEPT *end) const {

    int count = 0;

    const EDGEPT *pt = this;

    do {

      if (pt == end) {

        return true;

      }

      pt = pt->next;

      ++count;

    } while (pt != this && count <= min_points);

    return false;

  }

  // Accessors to hide or reveal a cut edge from feature extractors.

  void Hide() {

    is_hidden = true;

  }

  void Reveal() {

    is_hidden = false;

  }

  bool IsHidden() const {

    return is_hidden;

  }

  void MarkChop() {

    dir = 1;

  }

  bool IsChopPt() const {

    return dir != 0;

  }

  TPOINT pos; // position

  VECTOR vec; // vector to next point

  bool is_hidden = false;

  uint8_t runlength = 0;

  int8_t dir = 0;

  bool fixed = false;

  EDGEPT *next = nullptr;           // anticlockwise element

  EDGEPT *prev = nullptr;           // clockwise element

  C_OUTLINE *src_outline = nullptr; // Outline it came from.

  // The following fields are not used if src_outline is nullptr.

  int start_step = 0; // Location of pos in src_outline.

  int step_count = 0; // Number of steps used (may wrap around).

};

// For use in chop and findseam to keep a list of which EDGEPTs were inserted.

CLISTIZEH(EDGEPT)

struct TESSLINE {

  TESSLINE() : is_hole(false), loop(nullptr), next(nullptr) {}

  TESSLINE(const TESSLINE &src) : loop(nullptr), next(nullptr) {

    CopyFrom(src);

  }

  ~TESSLINE() {

    Clear();

  }

  TESSLINE &operator=(const TESSLINE &src) {

    CopyFrom(src);

    return *this;

  }

  // Consume the circular list of EDGEPTs to make a TESSLINE.

  static TESSLINE *BuildFromOutlineList(EDGEPT *outline);

  // Copies the data and the outline, but leaves next untouched.

  void CopyFrom(const TESSLINE &src);

  // Deletes owned data.

  void Clear();

  // Normalize in-place using the DENORM.

  void Normalize(const DENORM &denorm);

  // Rotates by the given rotation in place.

  void Rotate(const FCOORD rotation);

  // Moves by the given vec in place.

  void Move(const ICOORD vec);

  // Scales by the given factor in place.

  void Scale(float factor);

  // Sets up the start and vec members of the loop from the pos members.

  void SetupFromPos();

  // Recomputes the bounding box from the points in the loop.

  void ComputeBoundingBox();

  // Computes the min and max cross product of the outline points with the

  // given vec and returns the results in min_xp and max_xp. Geometrically

  // this is the left and right edge of the outline perpendicular to the

  // given direction, but to get the distance units correct, you would

  // have to divide by the modulus of vec.

  void MinMaxCrossProduct(const TPOINT vec, int *min_xp, int *max_xp) const;

  TBOX bounding_box() const;

  // Returns true if *this and other have equal bounding boxes.

  bool SameBox(const TESSLINE &other) const {

    return topleft == other.topleft && botright == other.botright;

  }

  // Returns true if the given line segment crosses any outline of this blob.

  bool SegmentCrosses(const TPOINT &pt1, const TPOINT &pt2) const {

    if (Contains(pt1) && Contains(pt2)) {

      EDGEPT *pt = loop;

      do {

        if (TPOINT::IsCrossed(pt1, pt2, pt->pos, pt->next->pos)) {

          return true;

        }

        pt = pt->next;

      } while (pt != loop);

    }

    return false;

  }

  // Returns true if the point is contained within the outline box.

  bool Contains(const TPOINT &pt) const {

    return topleft.x <= pt.x && pt.x <= botright.x && botright.y <= pt.y && pt.y <= topleft.y;

  }

#ifndef GRAPHICS_DISABLED

  void plot(ScrollView *window, ScrollView::Color color, ScrollView::Color child_color);

#endif // !GRAPHICS_DISABLED

  // Returns the first outline point that has a different src_outline to its

  // predecessor, or, if all the same, the lowest indexed point.

  EDGEPT *FindBestStartPt() const;

  int BBArea() const {

    return (botright.x - topleft.x) * (topleft.y - botright.y);

  }

  TPOINT topleft;  // Top left of loop.

  TPOINT botright; // Bottom right of loop.

  TPOINT start;    // Start of loop.

  bool is_hole;    // True if this is a hole/child outline.

  EDGEPT *loop;    // Edgeloop.

  TESSLINE *next;  // Next outline in blob.

};                 // Outline structure.

struct TBLOB {

  TBLOB() : outlines(nullptr) {}

  TBLOB(const TBLOB &src) : outlines(nullptr) {

    CopyFrom(src);

  }

  ~TBLOB() {

    Clear();

  }

  TBLOB &operator=(const TBLOB &src) {

    CopyFrom(src);

    return *this;

  }

  // Factory to build a TBLOB from a C_BLOB with polygonal approximation along

  // the way. If allow_detailed_fx is true, the EDGEPTs in the returned TBLOB

  // contain pointers to the input C_OUTLINEs that enable higher-resolution

  // feature extraction that does not use the polygonal approximation.

  static TBLOB *PolygonalCopy(bool allow_detailed_fx, C_BLOB *src);

  // Factory builds a blob with no outlines, but copies the other member data.

  static TBLOB *ShallowCopy(const TBLOB &src);

  // Normalizes the blob for classification only if needed.

  // (Normally this means a non-zero classify rotation.)

  // If no Normalization is needed, then nullptr is returned, and the input blob

  // can be used directly. Otherwise a new TBLOB is returned which must be

  // deleted after use.

  TBLOB *ClassifyNormalizeIfNeeded() const;

  // Copies the data and the outlines, but leaves next untouched.

  void CopyFrom(const TBLOB &src);

  // Deletes owned data.

  void Clear();

  // Sets up the built-in DENORM and normalizes the blob in-place.

  // For parameters see DENORM::SetupNormalization, plus the inverse flag for

  // this blob and the Pix for the full image.

  void Normalize(const BLOCK *block, const FCOORD *rotation, const DENORM *predecessor,

                 float x_origin, float y_origin, float x_scale, float y_scale, float final_xshift,

                 float final_yshift, bool inverse, Image pix);

  // Rotates by the given rotation in place.

  void Rotate(const FCOORD rotation);

  // Moves by the given vec in place.

  void Move(const ICOORD vec);

  // Scales by the given factor in place.

  void Scale(float factor);

  // Recomputes the bounding boxes of the outlines.

  void ComputeBoundingBoxes();

  // Returns the number of outlines.

  int NumOutlines() const;

  TBOX bounding_box() const;

  // Returns true if the given line segment crosses any outline of this blob.

  bool SegmentCrossesOutline(const TPOINT &pt1, const TPOINT &pt2) const {

    for (const TESSLINE *outline = outlines; outline != nullptr; outline = outline->next) {

      if (outline->SegmentCrosses(pt1, pt2)) {

        return true;

      }

    }

    return false;

  }

  // Returns true if the point is contained within any of the outline boxes.

  bool Contains(const TPOINT &pt) const {

    for (const TESSLINE *outline = outlines; outline != nullptr; outline = outline->next) {

      if (outline->Contains(pt)) {

        return true;

      }

    }

    return false;

  }

  // Finds and deletes any duplicate outlines in this blob, without deleting

  // their EDGEPTs.

  void EliminateDuplicateOutlines();

  // Swaps the outlines of *this and next if needed to keep the centers in

  // increasing x.

  void CorrectBlobOrder(TBLOB *next);

  const DENORM &denorm() const {

    return denorm_;

  }

#ifndef GRAPHICS_DISABLED

  void plot(ScrollView *window, ScrollView::Color color, ScrollView::Color child_color);

#endif // !GRAPHICS_DISABLED

  int BBArea() const {

    int total_area = 0;

    for (TESSLINE *outline = outlines; outline != nullptr; outline = outline->next) {

      total_area += outline->BBArea();

    }

    return total_area;

  }

  // Computes the center of mass and second moments for the old baseline and

  // 2nd moment normalizations. Returns the outline length.

  // The input denorm should be the normalizations that have been applied from

  // the image to the current state of this TBLOB.

  int ComputeMoments(FCOORD *center, FCOORD *second_moments) const;

  // Computes the precise bounding box of the coords that are generated by

  // GetEdgeCoords. This may be different from the bounding box of the polygon.

  void GetPreciseBoundingBox(TBOX *precise_box) const;

  // Adds edges to the given vectors.

  // For all the edge steps in all the outlines, or polygonal approximation

  // where there are no edge steps, collects the steps into x_coords/y_coords.

  // x_coords is a collection of the x-coords of vertical edges for each

  // y-coord starting at box.bottom().

  // y_coords is a collection of the y-coords of horizontal edges for each

  // x-coord starting at box.left().

  // Eg x_coords[0] is a collection of the x-coords of edges at y=bottom.

  // Eg x_coords[1] is a collection of the x-coords of edges at y=bottom + 1.

  void GetEdgeCoords(const TBOX &box, std::vector<std::vector<int>> &x_coords,

                     std::vector<std::vector<int>> &y_coords) const;

  TESSLINE *outlines; // List of outlines in blob.

private: // TODO(rays) Someday the data members will be private too.

  // For all the edge steps in all the outlines, or polygonal approximation

  // where there are no edge steps, collects the steps into the bounding_box,

  // llsq and/or the x_coords/y_coords. Both are used in different kinds of

  // normalization.

  // For a description of x_coords, y_coords, see GetEdgeCoords above.

  void CollectEdges(const TBOX &box, TBOX *bounding_box, LLSQ *llsq,

                    std::vector<std::vector<int>> *x_coords,

                    std::vector<std::vector<int>> *y_coords) const;

private:

  // DENORM indicating the transformations that this blob has undergone so far.

  DENORM denorm_;

}; // Blob structure.

struct TWERD {

  TWERD() : latin_script(false) {}

  TWERD(const TWERD &src) {

    CopyFrom(src);

  }

  ~TWERD() {

    Clear();

  }

  TWERD &operator=(const TWERD &src) {

    CopyFrom(src);

    return *this;

  }

  // Factory to build a TWERD from a (C_BLOB) WERD, with polygonal

  // approximation along the way.

  static TWERD *PolygonalCopy(bool allow_detailed_fx, WERD *src);

  // Baseline normalizes the blobs in-place, recording the normalization in the

  // DENORMs in the blobs.

  void BLNormalize(const BLOCK *block, const ROW *row, Image pix, bool inverse, float x_height,

                   float baseline_shift, bool numeric_mode, tesseract::OcrEngineMode hint,

                   const TBOX *norm_box, DENORM *word_denorm);

  // Copies the data and the blobs, but leaves next untouched.

  void CopyFrom(const TWERD &src);

  // Deletes owned data.

  void Clear();

  // Recomputes the bounding boxes of the blobs.

  void ComputeBoundingBoxes();

  // Returns the number of blobs in the word.

  unsigned NumBlobs() const {

    return blobs.size();

  }

  TBOX bounding_box() const;

  // Merges the blobs from start to end, not including end, and deletes

  // the blobs between start and end.

  void MergeBlobs(unsigned start, unsigned end);

#ifndef GRAPHICS_DISABLED

  void plot(ScrollView *window);

#endif // !GRAPHICS_DISABLED

  std::vector<TBLOB *> blobs; // Blobs in word.

  bool latin_script;          // This word is in a latin-based script.

};

/*----------------------------------------------------------------------

              F u n c t i o n s

----------------------------------------------------------------------*/

// TODO(rays) Make divisible_blob and divide_blobs members of TBLOB.

bool divisible_blob(TBLOB *blob, bool italic_blob, TPOINT *location);

void divide_blobs(TBLOB *blob, TBLOB *other_blob, bool italic_blob, const TPOINT &location);

} // namespace tesseract

#endif