find_package(Gint 2.1 REQUIRED)

# Ask the fxSDK to find a library called libexample.a, and find its version in
# the macro EX_VERSION of the header file <example/config.h>.
#
# Store the path to libexample.a in EX_PATH and store the version number in
# EX_VERSION.
include(FindSimpleLibrary)
find_simple_library(libexample.a example/config.h "EX_VERSION"
  PATH_VAR EX_PATH
  VERSION_VAR EX_VERSION)

# The fxSDK looks for libexample.a in ${FXSDK_LIB}, then <example/config.h> in
# ${FXSDK_INCLUDE}, and extracts the version number from a macro like
#
#  #define EX_VERSION "..."
#
# See the source code for the FindSimpleLibrary module for more detail.

# We then use a CMake function to finish searching the library. We specify:
#  * REQUIRED_VARS ... which requires the variables to be non-empty, otherwise
#    find_library() says the library was not found.
#  * VERSION_VAR ... which provides the version number, so that find_library()
#    can compare with the version requested by the user (if any) and fail if
#    the version we found isn't compatible.
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(LibExample
  REQUIRED_VARS EX_PATH EX_VERSION
  VERSION_VAR EX_VERSION)

# We now have a LibExample_FOUND variable indicating if everything went well.
# If so we can now create an *imported target* that is not built in the project
# but can still be linked against with target_link_libraries().
if(LibExample_FOUND)
  # This is an imported target, we don't build it, we just claim it's here.
  add_library(LibExample::LibExample UNKNOWN IMPORTED)
  # Here we declare the compiler and linker flags that every user of LibExample
  # needs to use.
  set_target_properties(LibExample::LibExample PROPERTIES
    # If we specify where the library comes from, CMake will watch that file
    # and relink any user application when the library is updated!
    IMPORTED_LOCATION "${EX_PATH}"
    # Linking options
    INTERFACE_LINK_OPTIONS -lexample
    # Dependencies (for order on the command-line)
    INTERFACE_LINK_LIBRARIES Gint::Gint)
endif()