// Copyright 2017 Google Inc. All Rights Reserved.
//
// 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.
//

// Author: ericv@google.com (Eric Veach)

#include "s2/s2builderutil_testing.h"

#include <memory>
#include <vector>

#include <gtest/gtest.h>
#include "s2/third_party/absl/memory/memory.h"

using absl::make_unique;
using std::unique_ptr;
using std::vector;

using EdgeType = S2Builder::EdgeType;
using Graph = S2Builder::Graph;
using GraphOptions = S2Builder::GraphOptions;

using DegenerateEdges = GraphOptions::DegenerateEdges;
using DuplicateEdges = GraphOptions::DuplicateEdges;
using SiblingPairs = GraphOptions::SiblingPairs;

namespace s2builderutil {

TEST(GraphCloningLayer, MakeIndependentCopy) {
  // Also tests GraphClone.
  GraphClone gc;
  S2Builder builder{S2Builder::Options()};
  GraphOptions graph_options(EdgeType::DIRECTED, DegenerateEdges::DISCARD,
                             DuplicateEdges::MERGE, SiblingPairs::KEEP);
  builder.StartLayer(make_unique<GraphCloningLayer>(graph_options, &gc));
  S2Point v0(1, 0, 0), v1(0, 1, 0);
  builder.set_label(14);
  builder.AddEdge(v0, v1);
  S2Error error;
  EXPECT_TRUE(builder.Build(&error));
  const Graph& g = gc.graph();
  EXPECT_TRUE(graph_options == g.options());
  EXPECT_EQ((vector<S2Point>{v0, v1}), g.vertices());
  EXPECT_EQ((vector<Graph::Edge>{{0, 1}}), g.edges());
  EXPECT_EQ(1, g.input_edge_ids(0).size());
  EXPECT_EQ(0, *g.input_edge_ids(0).begin());
  Graph::LabelFetcher fetcher(g, g.options().edge_type());
  vector<S2Builder::Label> labels;
  fetcher.Fetch(0, &labels);
  EXPECT_EQ((vector<S2Builder::Label>{14}), labels);
  // S2Builder sets a default IsFullPolygonPredicate that returns an error.
  EXPECT_TRUE(g.is_full_polygon_predicate() != nullptr);
}

TEST(GraphAppendingLayer, AppendsTwoGraphs) {
  vector<Graph> graphs;
  vector<unique_ptr<GraphClone>> clones;
  S2Builder builder{S2Builder::Options()};
  builder.StartLayer(make_unique<GraphAppendingLayer>(
      GraphOptions(), &graphs, &clones));
  S2Point v0(1, 0, 0), v1(0, 1, 0);
  builder.AddEdge(v0, v1);
  builder.StartLayer(make_unique<GraphAppendingLayer>(
      GraphOptions(), &graphs, &clones));
  builder.AddEdge(v1, v0);
  S2Error error;
  EXPECT_TRUE(builder.Build(&error));
  EXPECT_EQ(2, graphs.size());
  EXPECT_EQ(2, clones.size());
  EXPECT_EQ(v0, graphs[0].vertex(graphs[0].edge(0).first));
  EXPECT_EQ(v1, graphs[1].vertex(graphs[1].edge(0).first));
}

}  // namespace s2builderutil