find_package(Git)

if(GIT_EXECUTABLE)
  # Generate a git-describe version string from Git repository tags
  execute_process(
    COMMAND ${GIT_EXECUTABLE} describe --tags --dirty --match "v*"
    WORKING_DIRECTORY .
    OUTPUT_VARIABLE GIT_DESCRIBE_VERSION
    RESULT_VARIABLE GIT_DESCRIBE_ERROR_CODE
    OUTPUT_STRIP_TRAILING_WHITESPACE
    )
  if(NOT GIT_DESCRIBE_ERROR_CODE)
    set(CURRENT_TAG ${GIT_DESCRIBE_VERSION})
  endif()
endif()

# Final fallback: Just use a bogus version string that is semantically older
# than anything else and spit out a warning to the developer.
if(NOT DEFINED CURRENT_TAG)
  set(CURRENT_TAG 0.0.0)
  message(WARNING "Failed to determine FOOBAR_VERSION from Git tags. Using default version \"${CURRENT_TAG}\".")
endif()

string(REGEX MATCH "[^v-]+[\\.][0-9]+[\\.][0-9]+" CURRENT_VERSION ${CURRENT_TAG})

message(STATUS "Version is set at ${CURRENT_VERSION}")