#include <gtest/gtest.h>

#include <memory>
#include <sstream>
#include <vector>

#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>

#include "mocks/mock_data_array.h"
#include "mocks/mock_suffix_array.h"
#include "precomputation.h"

using namespace std;
using namespace ::testing;
namespace ar = boost::archive;

namespace extractor {
namespace {

class PrecomputationTest : public Test {
 protected:
  virtual void SetUp() {
    data = {4, 2, 3, 5, 7, 2, 3, 5, 2, 3, 4, 2, 1};
    data_array = make_shared<MockDataArray>();
    EXPECT_CALL(*data_array, GetData()).WillRepeatedly(ReturnRef(data));

    vector<int> suffixes{12, 8, 5, 1, 9, 6, 2, 0, 10, 7, 3, 4, 13};
    vector<int> lcp{-1, 0, 2, 3, 1, 0, 1, 2, 0, 2, 0, 1, 0, 0};
    suffix_array = make_shared<MockSuffixArray>();
    EXPECT_CALL(*suffix_array, GetData()).WillRepeatedly(Return(data_array));
    for (size_t i = 0; i < suffixes.size(); ++i) {
      EXPECT_CALL(*suffix_array,
                  GetSuffix(i)).WillRepeatedly(Return(suffixes[i]));
    }
    EXPECT_CALL(*suffix_array, BuildLCPArray()).WillRepeatedly(Return(lcp));

    precomputation = Precomputation(suffix_array, 3, 3, 10, 5, 1, 4, 2);
  }

  void CheckCollocation(const Collocations& collocations,
                        const vector<int>& collocation,
                        const vector<vector<int>>& locations) {
    for (auto location: locations) {
      auto item = make_pair(collocation, location);
      EXPECT_FALSE(find(collocations.begin(), collocations.end(), item) ==
                   collocations.end());
    }
  }

  void CheckIllegalCollocation(const Collocations& collocations,
                               const vector<int>& collocation) {
    for (auto item: collocations) {
      EXPECT_FALSE(collocation == item.first);
    }
  }

  vector<int> data;
  shared_ptr<MockDataArray> data_array;
  shared_ptr<MockSuffixArray> suffix_array;
  Precomputation precomputation;
};

TEST_F(PrecomputationTest, TestCollocations) {
  Collocations collocations = precomputation.GetCollocations();

  EXPECT_EQ(50, collocations.size());

  vector<int> collocation = {2, 3, -1, 2};
  vector<vector<int>> locations = {{1, 5}, {1, 8}, {5, 8}, {5, 11}, {8, 11}};
  CheckCollocation(collocations, collocation, locations);

  collocation = {2, 3, -1, 2, 3};
  locations = {{1, 5}, {1, 8}, {5, 8}};
  CheckCollocation(collocations, collocation, locations);

  collocation = {2, 3, -1, 3};
  locations = {{1, 6}, {1, 9}, {5, 9}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 2};
  locations = {{2, 5}, {2, 8}, {2, 11}, {6, 8}, {6, 11}, {9, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 3};
  locations = {{2, 6}, {2, 9}, {6, 9}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 2, 3};
  locations = {{2, 5}, {2, 8}, {6, 8}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 2};
  locations = {{1, 5}, {1, 8}, {5, 8}, {5, 11}, {8, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 2, 3};
  locations = {{1, 5}, {1, 8}, {5, 8}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 3};
  locations = {{1, 6}, {1, 9}, {5, 9}};
  CheckCollocation(collocations, collocation, locations);

  collocation = {2, -1, 2, -2, 2};
  locations = {{1, 5, 8}, {5, 8, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 2, -2, 3};
  locations = {{1, 5, 9}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 3, -2, 2};
  locations = {{1, 6, 8}, {5, 9, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {2, -1, 3, -2, 3};
  locations = {{1, 6, 9}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 2, -2, 2};
  locations = {{2, 5, 8}, {2, 5, 11}, {2, 8, 11}, {6, 8, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 2, -2, 3};
  locations = {{2, 5, 9}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 3, -2, 2};
  locations = {{2, 6, 8}, {2, 6, 11}, {2, 9, 11}, {6, 9, 11}};
  CheckCollocation(collocations, collocation, locations);
  collocation = {3, -1, 3, -2, 3};
  locations = {{2, 6, 9}};
  CheckCollocation(collocations, collocation, locations);

  // Collocation exceeds max_rule_symbols.
  collocation = {2, -1, 2, -2, 2, 3};
  CheckIllegalCollocation(collocations, collocation);
  // Collocation contains non frequent pattern.
  collocation = {2, -1, 5};
  CheckIllegalCollocation(collocations, collocation);
}

TEST_F(PrecomputationTest, TestSerialization) {
  stringstream stream(ios_base::out | ios_base::in);
  ar::text_oarchive output_stream(stream, ar::no_header);
  output_stream << precomputation;

  Precomputation precomputation_copy;
  ar::text_iarchive input_stream(stream, ar::no_header);
  input_stream >> precomputation_copy;

  EXPECT_EQ(precomputation, precomputation_copy);
}

} // namespace
} // namespace extractor