if(NOT DEFINED INPUT)
  message(FATAL_ERROR "write_json_header.cmake: INPUT not defined")
endif()
if(NOT DEFINED OUTPUT)
  message(FATAL_ERROR "write_json_header.cmake: OUTPUT not defined")
endif()

find_package(Python3 COMPONENTS Interpreter REQUIRED)

execute_process(
  COMMAND ${Python3_EXECUTABLE} -c "import json,sys;print(json.dumps(json.load(open(sys.argv[1])),separators=(', ',':')) )" ${INPUT}
  OUTPUT_VARIABLE MINIFIED_JSON
  OUTPUT_STRIP_TRAILING_WHITESPACE
)

if(NOT MINIFIED_JSON)
  message(FATAL_ERROR "write_json_header.cmake: failed to minify ${INPUT}")
endif()

file(WRITE ${OUTPUT} "#pragma once\nstatic const char MTR_LINE_STATION_JSON[] = R\"json(${MINIFIED_JSON})json\";\n")