// SPDX-License-Identifier: GPL-2.0-or-later
/** @file
 * TODO: insert short description here
 *//*
 * Authors: see git history
 *
 * Copyright (C) 2018 Authors
 * Released under GNU GPL v2+, read the file 'COPYING' for more information.
 */
#include <glibmm.h>

#include "attributes.h"
#include "display/cairo-utils.h"

#include "sp-mesh-gradient.h"

/*
 * Mesh Gradient
 */
//#define MESH_DEBUG
//#define OBJECT_TRACE

SPMeshGradient::SPMeshGradient() : SPGradient(), type( SP_MESH_TYPE_COONS ), type_set(false) {
#ifdef OBJECT_TRACE
  objectTrace( "SPMeshGradient::SPMeshGradient" );
#endif

    // Start coordinate of mesh
    this->x.unset(SVGLength::NONE, 0.0, 0.0);
    this->y.unset(SVGLength::NONE, 0.0, 0.0);

#ifdef OBJECT_TRACE
  objectTrace( "SPMeshGradient::SPMeshGradient", false );
#endif
}

SPMeshGradient::~SPMeshGradient() {
#ifdef OBJECT_TRACE
  objectTrace( "SPMeshGradient::~SPMeshGradient (empty function)" );
  objectTrace( "SPMeshGradient::~SPMeshGradient", false );
#endif
}

void SPMeshGradient::build(SPDocument *document, Inkscape::XML::Node *repr) {
#ifdef OBJECT_TRACE
  objectTrace( "SPMeshGradient::build" );
#endif

    SPGradient::build(document, repr);

    // Start coordinate of meshgradient
    this->readAttr(SPAttr::X);
    this->readAttr(SPAttr::Y);

    this->readAttr(SPAttr::TYPE);

#ifdef OBJECT_TRACE
    objectTrace( "SPMeshGradient::build", false );
#endif
}


void SPMeshGradient::set(SPAttr key, gchar const *value) {
#ifdef OBJECT_TRACE
  objectTrace( "SPMeshGradient::set" );
#endif

    switch (key) {
        case SPAttr::X:
            if (!this->x.read(value)) {
                this->x.unset(SVGLength::NONE, 0.0, 0.0);
            }

            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
            break;

        case SPAttr::Y:
            if (!this->y.read(value)) {
                this->y.unset(SVGLength::NONE, 0.0, 0.0);
            }

            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
            break;

        case SPAttr::TYPE:
	    if (value) {
	      if (!strcmp(value, "coons")) {
		this->type = SP_MESH_TYPE_COONS;
	      } else if (!strcmp(value, "bicubic")) {
		this->type = SP_MESH_TYPE_BICUBIC;
	      } else {
		std::cerr << "SPMeshGradient::set(): invalid value " << value << std::endl;
	      }
	      this->type_set = TRUE;
	    } else {
	      // std::cout << "SPMeshGradient::set() No value " << std::endl;
	      this->type = SP_MESH_TYPE_COONS;
	      this->type_set = FALSE;
	    }

            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
            break;

        default:
            SPGradient::set(key, value);
            break;
    }

#ifdef OBJECT_TRACE
    objectTrace( "SPMeshGradient::set", false );
#endif
}

/**
 * Write mesh gradient attributes to associated repr.
 */
Inkscape::XML::Node* SPMeshGradient::write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags) {
#ifdef OBJECT_TRACE
    objectTrace( "SPMeshGradient::write", false );
#endif

    if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
        repr = xml_doc->createElement("svg:meshgradient");
    }

    if ((flags & SP_OBJECT_WRITE_ALL) || this->x._set) {
    	repr->setAttributeSvgDouble("x", this->x.computed);
    }

    if ((flags & SP_OBJECT_WRITE_ALL) || this->y._set) {
    	repr->setAttributeSvgDouble("y", this->y.computed);
    }

    if ((flags & SP_OBJECT_WRITE_ALL) || this->type_set) {
        switch (this->type) {
	    case SP_MESH_TYPE_COONS:
	      repr->setAttribute("type", "coons");
	      break;
	    case SP_MESH_TYPE_BICUBIC:
	      repr->setAttribute("type", "bicubic");
	      break;
	    default:
	      // Do nothing
	      break;
	}
    }

    SPGradient::write(xml_doc, repr, flags);

#ifdef OBJECT_TRACE
    objectTrace( "SPMeshGradient::write", false );
#endif
    return repr;
}

cairo_pattern_t* SPMeshGradient::pattern_new(cairo_t * /*ct*/,
  Geom::OptRect const &bbox,
	double opacity)
{
  using Geom::X;
  using Geom::Y;

#ifdef MESH_DEBUG
  std::cout << "sp_meshgradient_create_pattern: " << (*bbox) << " " << opacity << std::endl;
#endif

  this->ensureArray();

  cairo_pattern_t *cp = nullptr;

  SPMeshNodeArray* my_array = &array;

  if( type_set ) {
    switch (type) {
    case SP_MESH_TYPE_COONS:
      // std::cout << "SPMeshGradient::pattern_new: Coons" << std::endl;
      break;
    case SP_MESH_TYPE_BICUBIC:
      array.bicubic( &array_smoothed, type );
      my_array = &array_smoothed;
      break;
    }
  }

  cp = cairo_pattern_create_mesh();

  for( unsigned int i = 0; i < my_array->patch_rows(); ++i ) {
    for( unsigned int j = 0; j < my_array->patch_columns(); ++j ) {

      SPMeshPatchI patch( &(my_array->nodes), i, j );

      cairo_mesh_pattern_begin_patch( cp );
      cairo_mesh_pattern_move_to( cp, patch.getPoint( 0, 0 )[X], patch.getPoint( 0, 0 )[Y] );

      for( unsigned int k = 0; k < 4; ++k ) {
#ifdef DEBUG_MESH
	std::cout << i << " " << j << " "
		  << patch.getPathType( k ) << "  (";
	for( int p = 0; p < 4; ++p ) {
	  std::cout << patch.getPoint( k, p );
	}
	std::cout << ") "
		  << patch.getColor( k ).toString() << std::endl;
#endif

	switch ( patch.getPathType( k ) ) {
	case 'l':
	case 'L':
	case 'z':
	case 'Z':
	  cairo_mesh_pattern_line_to( cp,
				      patch.getPoint( k, 3 )[X],
				      patch.getPoint( k, 3 )[Y] );
	  break;
	case 'c':
	case 'C':
	  {
	    std::vector< Geom::Point > pts = patch.getPointsForSide( k );
	    cairo_mesh_pattern_curve_to( cp,
					 pts[1][X], pts[1][Y],
					 pts[2][X], pts[2][Y],
					 pts[3][X], pts[3][Y] );
	    break;
	  }
	default:
	  // Shouldn't happen
	  std::cout << "sp_mesh_create_pattern: path error" << std::endl;
	}

	if( patch.tensorIsSet(k) ) {
	  // Tensor point defined relative to corner.
	  Geom::Point t = patch.getTensorPoint(k);
	  cairo_mesh_pattern_set_control_point( cp, k, t[X], t[Y] );
	  //std::cout << "  sp_mesh_create_pattern: tensor " << k
	  //          << " set to " << t << "." << std::endl;
	} else {
	  // Geom::Point t = patch.coonsTensorPoint(k);
	  //std::cout << "  sp_mesh_create_pattern: tensor " << k
	  //          << " calculated as " << t << "." <<std::endl;
	}

	cairo_mesh_pattern_set_corner_color_rgba(
						 cp, k,
						 patch.getColor( k ).v.c[0],
						 patch.getColor( k ).v.c[1],
						 patch.getColor( k ).v.c[2],
						 patch.getOpacity( k ) * opacity );
      }

      cairo_mesh_pattern_end_patch( cp );
    }
  }

  // set pattern matrix
  Geom::Affine gs2user = this->gradientTransform;
  if (this->getUnits() == SP_GRADIENT_UNITS_OBJECTBOUNDINGBOX) {
    Geom::Affine bbox2user(bbox->width(), 0, 0, bbox->height(), bbox->left(), bbox->top());
    gs2user *= bbox2user;
  }
  ink_cairo_pattern_set_matrix(cp, gs2user.inverse());

  /*
    cairo_pattern_t *cp = cairo_pattern_create_radial(
    rg->fx.computed, rg->fy.computed, 0,
    rg->cx.computed, rg->cy.computed, rg->r.computed);
    sp_gradient_pattern_common_setup(cp, gr, bbox, opacity);
  */

  return cp;
}
