# EGL powers the surfaceless headless context the GL tests assert pixels
# against. It is a *test-only* dependency: plot_core never links or includes it,
# so a machine without EGL can still build the library (-DPLOT_BUILD_TESTS=OFF).
# Prefer CMake's own module, fall back to pkg-config, and fail loudly if neither
# can supply EGL rather than silently dropping the GL tests.
find_package(EGL QUIET)
if(NOT EGL_FOUND)
  find_package(PkgConfig QUIET)
  if(PkgConfig_FOUND)
    pkg_check_modules(EGL_PC QUIET IMPORTED_TARGET egl)
  endif()
endif()

if(TARGET EGL::EGL)
  set(plot_egl_library EGL::EGL)
elseif(TARGET PkgConfig::EGL_PC)
  set(plot_egl_library PkgConfig::EGL_PC)
else()
  message(FATAL_ERROR
    "plot: PLOT_BUILD_TESTS=ON requires EGL (EGL/egl.h plus libEGL) for the headless "
    "OpenGL context used by the GL tests. Install it (e.g. libegl-dev, libegl1-mesa-dev "
    "or mesa-libEGL-devel) or configure with -DPLOT_BUILD_TESTS=OFF.")
endif()

add_executable(plot_tests
  main.cpp
  test_transform.cpp
  test_gl_context.cpp
  egl_headless.cpp
)
target_link_libraries(plot_tests PRIVATE plot::core ${plot_egl_library})
plot_apply_warnings(plot_tests)

add_test(NAME plot_tests COMMAND plot_tests)