#include <stan/math/prim/mat.hpp>
#include <gtest/gtest.h>

TEST(ErrorHandlingMatrix, checkSymmetric) {
  Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> y;
  
  y.resize(2,2);
  y << 1, 3, 3, 1;
  EXPECT_TRUE(stan::math::check_symmetric("checkSymmetric",
                                                    "y", y));

  y(0,1) = 3.5;
  EXPECT_THROW(stan::math::check_symmetric("checkSymmetric", "y", y),
               std::domain_error);
}

TEST(ErrorHandlingMatrix, checkSymmetric_one_indexed_message) {
  Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> y;
  std::string message;
  
  y.resize(2,2);
  y << 1, 0, 3, 1;
  try {
    stan::math::check_symmetric("checkSymmetric", "y", y);
    FAIL() << "should have thrown";
  } catch (std::domain_error& e) {
    message = e.what();
  } catch (...) {
    FAIL() << "threw the wrong error";
  }

  EXPECT_NE(std::string::npos, message.find("[1,2]"))
    << message;
  EXPECT_NE(std::string::npos, message.find("[2,1]"))
    << message;
}

TEST(ErrorHandlingMatrix, checkSymmetric_nan) {
  Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> y;
  double nan = std::numeric_limits<double>::quiet_NaN();

  y.resize(2,2);
  y << 1, nan, 3, 1;
  EXPECT_THROW(stan::math::check_symmetric("checkSymmetric",
                                                     "y", y),
               std::domain_error);
  y << nan, 3, 3, 1;
  EXPECT_TRUE(stan::math::check_symmetric("checkSymmetric",
                                                    "y", y));

  y.resize(1,1);
  y << nan;
  EXPECT_TRUE(stan::math::check_symmetric("checkSymmetric",
                                                    "y", y));
}

TEST(ErrorHandlingMatrix, checkSymmetric_non_square) {
  Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> y;
  
  y.resize(2,3);
  EXPECT_THROW(stan::math::check_symmetric("checkSymmetric",
                                                     "y", y),
               std::invalid_argument);

}
