#include "fesa/app/fesa_application.h"

#include <gtest/gtest.h>
#include <hdf5.h>

#include <atomic>
#include <chrono>
#include <filesystem>
#include <fstream>
#include <stdexcept>
#include <string>
#include <vector>

namespace {

class TempDirectory {
 public:
  explicit TempDirectory(const std::string& label) {
    static std::atomic<unsigned long long> sequence{0U};
    const auto tick =
        std::chrono::steady_clock::now().time_since_epoch().count();
    path_ = std::filesystem::temp_directory_path() /
            ("fesa-step10-nonlinear-" + label + "-" +
             std::to_string(tick) + "-" +
             std::to_string(sequence.fetch_add(1U)));
    std::error_code error;
    if (!std::filesystem::create_directory(path_, error) || error) {
      throw std::runtime_error{"Unable to create nonlinear procedure fixture."};
    }
  }

  TempDirectory(const TempDirectory&) = delete;
  TempDirectory& operator=(const TempDirectory&) = delete;

  ~TempDirectory() {
    std::error_code ignored;
    std::filesystem::remove_all(path_, ignored);
  }

  const std::filesystem::path& Path() const noexcept { return path_; }

 private:
  std::filesystem::path path_;
};

void WriteText(const std::filesystem::path& path, const std::string& text) {
  std::ofstream stream{path, std::ios::binary | std::ios::trunc};
  stream.write(text.data(), static_cast<std::streamsize>(text.size()));
  if (!stream) {
    throw std::runtime_error{"Unable to write nonlinear procedure input."};
  }
}

std::string AllConstrainedNonlinearShellDeck() {
  return R"inp(*Part, name=ShellPart
*Node
1, 0., 0., 0.
2, 1., 0., 0.
3, 1., 1., 0.
4, 0., 1., 0.
*Element, type=S4
1, 1, 2, 3, 4
*Elset, elset=ShellSet
1
*Shell Section, elset=ShellSet, material=Steel
0.1
*End Part
*Assembly, name=Assembly
*Instance, name=Shell-1, part=ShellPart
*End Instance
*Nset, nset=All, instance=Shell-1
1, 2, 3, 4
*End Assembly
*Material, name=Steel
*Elastic
1000., 0.25
*Boundary
All, 1, 6
*Step, name=Step-1, nlgeom=YES
*Static
0.1, 1., 0.001, 0.1
*End Step
)inp";
}

class Hdf5File {
 public:
  explicit Hdf5File(const std::filesystem::path& path)
      : handle_{H5Fopen(path.string().c_str(), H5F_ACC_RDONLY, H5P_DEFAULT)} {
    if (handle_ < 0) {
      throw std::runtime_error{"Unable to open nonlinear results HDF5."};
    }
  }

  Hdf5File(const Hdf5File&) = delete;
  Hdf5File& operator=(const Hdf5File&) = delete;

  ~Hdf5File() { (void)H5Fclose(handle_); }

  hid_t Get() const noexcept { return handle_; }

 private:
  hid_t handle_;
};

std::string ReadStringAttribute(const hid_t object, const char* name) {
  const hid_t attribute = H5Aopen(object, name, H5P_DEFAULT);
  const hid_t type = attribute < 0 ? -1 : H5Aget_type(attribute);
  if (attribute < 0 || type < 0) {
    if (type >= 0) {
      (void)H5Tclose(type);
    }
    if (attribute >= 0) {
      (void)H5Aclose(attribute);
    }
    throw std::runtime_error{"Unable to read nonlinear metadata attribute."};
  }
  char* value = nullptr;
  const herr_t read = H5Aread(attribute, type, &value);
  const std::string result = read >= 0 && value != nullptr ? value : "";
  if (value != nullptr) {
    (void)H5free_memory(value);
  }
  (void)H5Tclose(type);
  (void)H5Aclose(attribute);
  if (read < 0) {
    throw std::runtime_error{"Unable to read nonlinear metadata text."};
  }
  return result;
}

// NSNR-PROC-004, NSNR-PROC-007, and NSNR-PROC-010.
TEST(NonlinearStaticProcedure,
     AllConstrainedNlgeomRunWritesSchemaV1AfterAcceptedFrames) {
  TempDirectory directory{"schema-v1"};
  const auto input = directory.Path() / "shellnl.inp";
  const auto output = directory.Path() / "shellnl_results.h5";
  WriteText(input, AllConstrainedNonlinearShellDeck());

  testing::internal::CaptureStderr();
  const int exit_code = fesa::FesaApplication{}.Run({input.string()});
  const std::string standard_error = testing::internal::GetCapturedStderr();

  ASSERT_EQ(exit_code, 0) << standard_error;
  ASSERT_TRUE(std::filesystem::exists(output));
  ASSERT_GT(H5Fis_hdf5(output.string().c_str()), 0);
  const Hdf5File file{output};
  const hid_t metadata = H5Gopen2(file.Get(), "/metadata", H5P_DEFAULT);
  ASSERT_GE(metadata, 0);
  EXPECT_EQ(ReadStringAttribute(metadata, "feature_id"),
            "nonlinear-static-newton-raphson");
  (void)H5Gclose(metadata);
  EXPECT_GT(H5Lexists(file.Get(), "/steps/Step-1/accepted_frames", H5P_DEFAULT),
            0);
}

}  // namespace