#include <catch2/catch.hpp>
#include "../src/fol/Lexer.hpp"

using namespace sp::fol;

class LexerTest
{
public:
  explicit LexerTest() {}
  virtual ~LexerTest() {}

  void test_next(Lexer& lexer, std::string const& oracle)
  {
    auto token = lexer.next();
    REQUIRE(nullptr != token);
    REQUIRE(oracle == token->string());
  }

  void test_end(Lexer& lexer)
  {
    auto token = lexer.next();
    REQUIRE(nullptr == token);
  }

protected:
};

TEST_CASE_METHOD(LexerTest, "Lexer_var")
{
  Lexer lexer;
  lexer.scan("hello");

  test_next(lexer, "VAR[hello]");
  test_end(lexer);
}

TEST_CASE_METHOD(LexerTest, "Lexer_operators")
{
  Lexer lexer;
  lexer.scan("&!salut|(monde)->hello");

  test_next(lexer, "AND");
  test_next(lexer, "NOT");
  test_next(lexer, "VAR[salut]");
  test_next(lexer, "OR");
  test_next(lexer, "OPAR");
  test_next(lexer, "VAR[monde]");
  test_next(lexer, "CPAR");
  test_next(lexer, "IMP");
  test_next(lexer, "VAR[hello]");
  test_end(lexer);
}

TEST_CASE_METHOD(LexerTest, "Lexer_pred")
{
  Lexer lexer;
  lexer.scan("Hello");

  test_next(lexer, "PRED[Hello]");
  test_end(lexer);
}

TEST_CASE_METHOD(LexerTest, "Lexer_const")
{
  Lexer lexer;
  lexer.scan("HELLO");

  test_next(lexer, "CONST[HELLO]");
  test_end(lexer);
}