#Designed by Wang Bin(Lucas Wang). 2013 <wbsecg1@gmail.com>

#cache mkspecs. compare mkspec with cached one. if not equal, remove old cache to run new compile tests
#TODO: Qt5 does not have QMAKE_MKSPECS, use QMAKE_SPEC, QMAKE_XSPEC
mkspecs_build = $$[QMAKE_MKSPECS]
mkspecs_build ~= s,\\\\,/,g #avoid warning for '\'. qmake knows how to deal with '/'
!isEmpty(mkspecs_cached) {
    !isEqual(mkspecs_cached, $$mkspecs_build):CONFIG += recheck
} else {
    CONFIG += recheck
}

##TODO: BUILD_DIR=>BUILD_ROOT
#if not empty, it means the parent project may already set it
isEmpty(out_dir):out_dir = $$OUT_PWD
out_dir ~= s,\\\\,/,g #avoid warning for '\'. qmake knows how to deal with '/'
isEmpty(SOURCE_ROOT):SOURCE_ROOT = $$PWD
SOURCE_ROOT ~= s,\\\\,/,g #avoid warning for '\'. qmake knows how to deal with '/'
isEmpty(BUILD_DIR):BUILD_DIR=$$out_dir
message("BUILD_DIR=$$BUILD_DIR")

greaterThan(QT_MAJOR_VERSION, 4) {
    #recheck:write_file($$BUILD_DIR/.qmake.cache) #FIXME: empty_file result in no qtCompileTest result in cache
    load(configure)
} else {
    _QMAKE_CACHE_QT4_ = $$_QMAKE_CACHE_
    #_QMAKE_CACHE_QT4_ is built in and always not empty
    isEmpty(_QMAKE_CACHE_QT4_)|isEqual(_QMAKE_CACHE_QT4_,) {
        _QMAKE_CACHE_QT4_=$$BUILD_DIR/.qmake.cache
    }
    include(common.pri)
    #recheck:write_file($$BUILD_DIR/.qmake.cache) #FIXME: empty_file result in no qtCompileTest result in cache
    #use the following lines when building as a sub-project, write cache to this project src dir.
    #if build this project alone and do not have sub-project depends on this lib, those lines are not necessary
    ####ASSUME compile tests and .qmake.cache is in project out root dir
    #vars in .qmake.cache will affect all projects in subdirs, even if qmake's working dir is not in .qmake.cache dir
    #write_file($$BUILD_DIR/.qmake.cache) ##TODO: erase the existing lines!!
    include(configure.pri)
#clear config.log iff reconfigure is required
    write_file($$QMAKE_CONFIG_LOG)
    #cache() is available after include configure.pri
    #load(configure.pri) #what's the difference?
    message("cache: $$_QMAKE_CACHE_QT4_")
}
cache(BUILD_DIR, set, BUILD_DIR)
#cache(BUILD_ROOT, set, BUILD_DIR)
cache(SOURCE_ROOT, set, SOURCE_ROOT)
cache(mkspecs_cached, set, mkspecs_build)

#config.tests
!isEmpty(EssentialDepends) {
    for(d, EssentialDepends) {
       !config_$$d {
            CONFIG *= recheck
       }
       qtCompileTest($$d)|error("$$d is required, but compiler can not find it")
    #   CONFIG -= recheck
    }
}
!isEmpty(OptionalDepends) {
    message("checking for optional features...")
    for(d, OptionalDepends) {
        qtCompileTest($$d)
    }
}

!isEmpty(EssentialDepends)|!isEmpty(OptionalDepends) {
    message("To recheck the dependencies, delete .qmake.cache or run qmake with argument 'CONFIG+=recheck'")
}