#include "iterator/recursive_iterator.hpp"

#include <vector>

#include "xcode_gtest_helper.h"

TEST(RecursiveIteratorVecTest, PreIncrementAdvancesIterator) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator(vec);
  EXPECT_THAT(*rit, 1);
  EXPECT_THAT(*++rit, 2);
  EXPECT_THAT(*rit, 2);
}

TEST(RecursiveIteratorVecTest, PostIncrementReturnsCopyOfPrev) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator(vec);
  EXPECT_THAT(*rit, 1);
  EXPECT_THAT(*rit++, 1);
  EXPECT_THAT(*rit, 2);
}

TEST(RecursiveIteratorVecTest, IterDistanceIsSumOfInnerContainerSizes) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator(vec);
  decltype(rit) end{};

  // TODO: Actually perform the summation?
  EXPECT_THAT(std::distance(rit, end), 5);
}

TEST(RecursiveIteratorVecTest, FlattensVectorDataLikeJoinIterator) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  std::vector<int> const expected{1, 2, 3, 4, 5};
  auto rit = make_recursive_iterator(vec);
  decltype(expected) result(rit, decltype(rit)());
  EXPECT_THAT(result, expected);
}

TEST(RecursiveIteratorVecTest, CanMutatePointedToData) {
  std::vector<std::vector<std::vector<int>>> vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator(vec);
  *rit = 6;
  EXPECT_THAT(vec[0][0][0], 6);
}

TEST(BoundedRecursiveIteratorVecTest, PreIncrementAdvancesIterator) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator<2>(vec);
  EXPECT_THAT(*rit, vec[0][0]);
  EXPECT_THAT(*++rit, vec[1][0]);
  EXPECT_THAT(*rit, vec[1][0]);
}

TEST(BoundedRecursiveIteratorVecTest, PostIncrementReturnsCopyOfPrev) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator<2>(vec);
  EXPECT_THAT(*rit, vec[0][0]);
  EXPECT_THAT(*rit++, vec[0][0]);
  EXPECT_THAT(*rit, vec[1][0]);
}

TEST(BoundedRecursiveIteratorVecTest, IterDistanceSumOnNLayersSize) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator<2>(vec);
  decltype(rit) end{};

  EXPECT_THAT(std::distance(rit, end), 3);
}

TEST(BoundedRecursiveIteratorVecTest, ElementsAreUnwrappedAsATuple) {
  std::vector<std::vector<std::vector<int>>> const vec{{{1, 2}}, {{3}, {4, 5}}};
  std::vector<std::vector<int>> const expected{{1, 2}, {3}, {4, 5}};
  auto rit = make_recursive_iterator<2>(vec);
  decltype(expected) result(rit, decltype(rit)());
  EXPECT_THAT(result, expected);
}

TEST(BoundedRecursiveIteratorVecTest, CanMutatePointedToData) {
  std::vector<std::vector<std::vector<int>>> vec{{{1, 2}}, {{3}, {4, 5}}};
  auto rit = make_recursive_iterator<2>(vec);
  rit->clear();
  EXPECT_THAT(vec[0][0], testing::IsEmpty());
}