/*

  KLayout Layout Viewer
  Copyright (C) 2006-2023 Matthias Koefferlein

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/


#include "dbTriangles.h"
#include "tlUnitTest.h"

#include <set>
#include <vector>
#include <cstdlib>
#include <cmath>

TEST(Triangle_basic)
{
  db::Triangles tris;
  tris.init_box (db::DBox (1, 0, 5, 4));

  EXPECT_EQ (tris.bbox ().to_string (), "(1,0;5,4)");
  EXPECT_EQ (tris.to_string (), "((1, 0), (1, 4), (5, 0)), ((1, 4), (5, 4), (5, 0))");

  EXPECT_EQ (tris.check (), true);
}

TEST(Triangle_flip)
{
  db::Triangles tris;
  tris.init_box (db::DBox (0, 0, 1, 1));
  EXPECT_EQ (tris.to_string (), "((0, 0), (0, 1), (1, 0)), ((0, 1), (1, 1), (1, 0))");

  EXPECT_EQ (tris.num_triangles (), size_t (2));

  const db::Triangle &t1 = *tris.begin ();
  db::TriangleEdge *diag_segment;
  for (int i = 0; i < 3; ++i) {
    diag_segment = t1.edge (i);
    if (diag_segment->side_of (db::DPoint (0.5, 0.5)) == 0) {
      break;
    }
  }
  tris.flip (diag_segment);
  EXPECT_EQ (tris.to_string (), "((1, 1), (0, 0), (0, 1)), ((1, 1), (1, 0), (0, 0))");
  EXPECT_EQ (tris.check (), true);
}

TEST(Triangle_insert)
{
  db::Triangles tris;
  tris.init_box (db::DBox (0, 0, 1, 1));

  tris.insert_point (0.2, 0.2);
  EXPECT_EQ (tris.to_string (), "((0, 0), (0, 1), (0.2, 0.2)), ((1, 0), (0, 0), (0.2, 0.2)), ((1, 1), (0.2, 0.2), (0, 1)), ((1, 1), (1, 0), (0.2, 0.2))");
  EXPECT_EQ (tris.check (), true);
}

TEST(Triangle_split_segment)
{
  db::Triangles tris;
  tris.init_box (db::DBox (0, 0, 1, 1));

  tris.insert_point (0.5, 0.5);
  EXPECT_EQ (tris.to_string (), "((1, 1), (1, 0), (0.5, 0.5)), ((1, 1), (0.5, 0.5), (0, 1)), ((0, 0), (0, 1), (0.5, 0.5)), ((0, 0), (0.5, 0.5), (1, 0))");
  EXPECT_EQ (tris.check(), true);
}

TEST(Triangle_insert_vertex_twice)
{
  db::Triangles tris;
  tris.init_box (db::DBox (0, 0, 1, 1));

  tris.insert_point (0.5, 0.5);
  //  inserted a vertex twice does not change anything
  tris.insert_point (0.5, 0.5);
  EXPECT_EQ (tris.to_string (), "((1, 1), (1, 0), (0.5, 0.5)), ((1, 1), (0.5, 0.5), (0, 1)), ((0, 0), (0, 1), (0.5, 0.5)), ((0, 0), (0.5, 0.5), (1, 0))");
  EXPECT_EQ (tris.check(), true);
}

TEST(Triangle_insert_vertex_convex)
{
  db::Triangles tris;
  tris.insert_point (0.2, 0.2);
  tris.insert_point (0.2, 0.8);
  tris.insert_point (0.6, 0.5);
  tris.insert_point (0.7, 0.5);
  tris.insert_point (0.6, 0.4);
  EXPECT_EQ (tris.to_string (), "((0.2, 0.2), (0.2, 0.8), (0.6, 0.5)), ((0.7, 0.5), (0.6, 0.5), (0.2, 0.8)), ((0.6, 0.5), (0.6, 0.4), (0.2, 0.2)), ((0.6, 0.5), (0.7, 0.5), (0.6, 0.4))");
  EXPECT_EQ (tris.check(), true);
}

TEST(Triangle_insert_vertex_convex2)
{
  db::Triangles tris;
  tris.insert_point (0.25, 0.1);
  tris.insert_point (0.1, 0.4);
  tris.insert_point (0.4, 0.15);
  tris.insert_point (1, 0.7);
  EXPECT_EQ (tris.to_string (), "((0.25, 0.1), (0.1, 0.4), (0.4, 0.15)), ((1, 0.7), (0.4, 0.15), (0.1, 0.4))");
  EXPECT_EQ (tris.check(), true);
}

TEST(Triangle_insert_vertex_convex3)
{
  db::Triangles tris;
  tris.insert_point (0.25, 0.5);
  tris.insert_point (0.25, 0.55);
  tris.insert_point (0.15, 0.8);
  tris.insert_point (1, 0.4);
  EXPECT_EQ (tris.to_string (), "((0.25, 0.5), (0.15, 0.8), (0.25, 0.55)), ((1, 0.4), (0.25, 0.5), (0.25, 0.55)), ((0.15, 0.8), (1, 0.4), (0.25, 0.55))");
  EXPECT_EQ (tris.check(), true);
}

TEST(Triangle_search_edges_crossing)
{
  db::Triangles tris;
  db::Vertex *v1 = tris.insert_point (0.2, 0.2);
  db::Vertex *v2 = tris.insert_point (0.2, 0.8);
  db::Vertex *v3 = tris.insert_point (0.6, 0.5);
  /*db::Vertex *v4 =*/ tris.insert_point (0.7, 0.5);
  db::Vertex *v5 = tris.insert_point (0.6, 0.4);
  db::Vertex *v6 = tris.insert_point (0.7, 0.2);
  EXPECT_EQ (tris.check(), true);

  auto xedges = tris.search_edges_crossing (v2, v6);

  EXPECT_EQ (xedges.size (), size_t (2));
  auto s1 = tris.find_edge_for_points (*v1, *v3);
  auto s2 = tris.find_edge_for_points (*v1, *v5);
  EXPECT_EQ (std::find (xedges.begin (), xedges.end (), s1) != xedges.end (), true);
  EXPECT_EQ (std::find (xedges.begin (), xedges.end (), s2) != xedges.end (), true);
}

//  Returns a random float number between 0.0 and 1.0
inline double flt_rand ()
{
  return rand () * (1.0 / double (RAND_MAX));
}

namespace {
  struct PointLessOp
  {
    bool operator() (const db::DPoint &a, const db::DPoint &b) const
    {
      return a.less (b);
    }
  };
}

TEST(Triangle_test_heavy_insert)
{
  tl::info << "Running test_heavy_insert " << tl::noendl;

  for (unsigned int l = 0; l < 100; ++l) {

    srand (l);
    tl::info << "." << tl::noendl;

    db::Triangles tris;
    double res = 128.0;

    unsigned int n = rand () % 190 + 10;

    db::DBox bbox;
    std::map<db::DPoint, bool, PointLessOp> vmap;

    for (unsigned int i = 0; i < n; ++i) {
      double x = round (flt_rand () * res) * (1.0 / res);
      double y = round (flt_rand () * res) * (1.0 / res);
      db::Vertex *v = tris.insert_point (x, y);
      bbox += db::DPoint (x, y);
      vmap.insert (std::make_pair (*v, false));
    }

    //  not strictly true, but very likely with at least 10 vertexes:
    EXPECT_EQ (tris.num_triangles () > 0, true);
    EXPECT_EQ (tris.bbox ().to_string (), bbox.to_string ());

    bool ok = true;
    for (auto t = tris.begin (); t != tris.end (); ++t) {
      for (int i = 0; i < 3; ++i) {
        auto f = vmap.find (*t->vertex (i));
        if (f == vmap.end ()) {
          tl::error << "Could not identify triangle vertex " << t->vertex (i)->to_string () << " as inserted vertex";
          ok = false;
        } else {
          f->second = true;
        }
      }
    }
    for (auto m = vmap.begin (); m != vmap.end (); ++m) {
      if (!m->second) {
        tl::error << "Could not identify vertex " << m->first.to_string () << " with a triangle";
        ok = false;
      }
    }
    EXPECT_EQ (ok, true);

    EXPECT_EQ (tris.check(), true);

  }

  tl::info << tl::endl << "done.";
}

TEST(Triangle_test_heavy_remove)
{
  tl::info << "Running test_heavy_remove " << tl::noendl;

  for (unsigned int l = 0; l < 100; ++l) {

    srand (l);
    tl::info << "." << tl::noendl;

    db::Triangles tris;
    double res = 128.0;

    unsigned int n = rand () % 190 + 10;

    for (unsigned int i = 0; i < n; ++i) {
      double x = round (flt_rand () * res) * (1.0 / res);
      double y = round (flt_rand () * res) * (1.0 / res);
      tris.insert_point (x, y);
    }

    EXPECT_EQ (tris.check(), true);

    std::set<db::Vertex *> vset;
    std::vector<db::Vertex *> vertexes;
    for (auto t = tris.begin (); t != tris.end (); ++t) {
      for (int i = 0; i < 3; ++i) {
        db::Vertex *v = t->vertex (i);
        if (vset.insert (v).second) {
          vertexes.push_back (v);
        }
      }
    }

    int loop = 0; // @@@
    while (! vertexes.empty ()) {
      ++loop; printf("@@@ %d\n", loop); fflush(stdout);
      if (loop == 38) {
        printf("@@@BANG!\n"); // @@@
      }

      unsigned int n = rand () % (unsigned int) vertexes.size ();
      db::Vertex *v = vertexes [n];
      tris.remove (v);
      vertexes.erase (vertexes.begin () + n);

      EXPECT_EQ (tris.check (), true);

    }

    EXPECT_EQ (tris.num_triangles (), size_t (0));

  }

  tl::info << tl::endl << "done.";
}