#include "kernel/filesystem/open_file_description.hpp"

#include "kernel/test_support/filesystem/inode.hpp"

#include <kstd/memory>
#include <kstd/print>
#include <kstd/vector>

#include <catch2/catch_test_macros.hpp>

SCENARIO("Open file description construction", "[filesystem][open_file_description]")
{
  GIVEN("an inode and an open file description for that inode")
  {
    auto inode = kstd::make_shared<kernel::tests::filesystem::inode>();
    auto file_description = kernel::filesystem::open_file_description{inode};

    THEN("the initial offset is zero")
    {
      REQUIRE(file_description.offset() == 0);
    }
  }
}

SCENARIO("Open file description read/write offset management", "[filesystem][open_file_description]")
{
  GIVEN("an inode that tracks read/write calls and an open file description for that inode")
  {
    auto inode = kstd::make_shared<kernel::tests::filesystem::inode>();
    auto file_description = kernel::filesystem::open_file_description{inode};

    THEN("the offset is updated correctly after reads")
    {
      REQUIRE(file_description.read(nullptr, 100) == 100);
      REQUIRE(file_description.offset() == 100);
      REQUIRE(file_description.read(nullptr, 50) == 50);
      REQUIRE(file_description.offset() == 150);
    }

    THEN("the offset is updated correctly after writes")
    {
      REQUIRE(file_description.write(nullptr, 200) == 200);
      REQUIRE(file_description.offset() == 200);
      REQUIRE(file_description.write(nullptr, 25) == 25);
      REQUIRE(file_description.offset() == 225);
    }

    THEN("reads and writes both update the same offset")
    {
      REQUIRE(file_description.read(nullptr, 10) == 10);
      REQUIRE(file_description.offset() == 10);
      REQUIRE(file_description.write(nullptr, 20) == 20);
      REQUIRE(file_description.offset() == 30);
      REQUIRE(file_description.read(nullptr, 5) == 5);
      REQUIRE(file_description.offset() == 35);
      REQUIRE(file_description.write(nullptr, 15) == 15);
      REQUIRE(file_description.offset() == 50);
    }
  }
}