# Copyright 2006 Vladimir Prus
# Distributed under the Boost Software License, Version 1.0.
# (See accompanying file LICENSE.txt or https://www.bfgroup.xyz/b2/LICENSE.txt)

# Support for the Qt GUI library version 3
# (http://www.trolltech.com/products/qt3/index.html).
# For new developments, it is recommended to use Qt4 via the qt4 B2
# module.

import modules ;
import feature ;
import errors ;
import type ;
import "class" : new ;
import generators ;
import project ;
import toolset : flags ;

# Convert this module into a project, so that we can declare targets here.
project.initialize $(__name__) ;
project qt3 ;


# Initialized the QT support module. The 'prefix' parameter tells where QT is
# installed. When not given, environmental variable QTDIR should be set.
#
rule init ( prefix ? )
{
    if ! $(prefix)
    {
        prefix = [ modules.peek : QTDIR ] ;
        if ! $(prefix)
        {
            errors.error
              "QT installation prefix not given and QTDIR variable is empty" ;
        }
    }

    if $(.initialized)
    {
        if $(prefix) != $(.prefix)
        {
            errors.error
              "Attempt the reinitialize QT with different installation prefix" ;
        }
    }
    else
    {
        .initialized = true ;
        .prefix = $(prefix) ;

        generators.register-standard qt3.moc : H : CPP(moc_%) : <allow>qt3 ;
        # Note: the OBJ target type here is fake, take a look at
        # qt4.jam/uic-h-generator for explanations that apply in this case as
        # well.
        generators.register [ new moc-h-generator-qt3
            qt3.moc.cpp : MOCCABLE_CPP : OBJ : <allow>qt3 ] ;

        # The UI type is defined in types/qt.jam, and UIC_H is only used in
        # qt.jam, but not in qt4.jam, so define it here.
        type.register UIC_H : : H ;

        generators.register-standard qt3.uic-h : UI : UIC_H : <allow>qt3 ;

        # The following generator is used to convert UI files to CPP. It creates
        # UIC_H from UI, and constructs CPP from UI/UIC_H. In addition, it also
        # returns UIC_H target, so that it can be mocced.
        class "qt::uic-cpp-generator" : generator
        {
            rule __init__ ( )
            {
                generator.__init__ qt3.uic-cpp : UI UIC_H : CPP : <allow>qt3 ;
            }

            rule run ( project name ? : properties * : sources + )
            {
                # Consider this:
                #    obj test : test_a.cpp : <optimization>off ;
                #
                # This generator will somehow be called in this case, and,
                # will fail -- which is okay. However, if there are <library>
                # properties they will be converted to sources, so the size of
                # 'sources' will be more than 1. In this case, the base generator
                # will just crash -- and that's not good. Just use a quick test
                # here.

                local result ;
                if ! $(sources[2])
                {
                    # Construct CPP as usual
                    result = [ generator.run $(project) $(name)
                      : $(properties) : $(sources) ] ;

                    # If OK, process UIC_H with moc. It's pretty clear that
                    # the object generated with UIC will have Q_OBJECT macro.
                    if $(result)
                    {
                        local action = [ $(result[1]).action ] ;
                        local sources = [ $(action).sources ] ;
                        local mocced = [ generators.construct $(project) $(name)
                          : CPP : $(properties) : $(sources[2]) ] ;
                        result += $(mocced[2-]) ;
                    }
                }

                return $(result) ;
            }
        }

        generators.register [ new "qt::uic-cpp-generator" ] ;

        # Finally, declare prebuilt target for QT library.
        local usage-requirements =
             <include>$(.prefix)/include
             <dll-path>$(.prefix)/lib
             <library-path>$(.prefix)/lib
             <allow>qt3
             ;
        lib qt : : <name>qt-mt <threading>multi : : $(usage-requirements) ;
        lib qt : : <name>qt <threading>single : : $(usage-requirements) ;
    }
}

class moc-h-generator-qt3 : generator
{
    rule __init__ ( * : * )
    {
        generator.__init__ $(1) : $(2) : $(3) : $(4) : $(5) : $(6) : $(7) : $(8) : $(9) ;
    }

    rule run ( project name ? : property-set : sources * )
    {
        if ! $(sources[2]) && [ $(sources[1]).type ] = MOCCABLE_CPP
        {
            name = [ $(sources[1]).name ] ;
            name = $(name:B) ;

            local a = [ new action $(sources[1]) : qt3.moc.cpp :
              $(property-set) ] ;

            local target = [
              new file-target $(name) : MOC : $(project) : $(a) ] ;

            local r = [ virtual-target.register $(target) ] ;

            # Since this generator will return a H target, the linking generator
            # won't use it at all, and won't set any dependency on it. However,
            # we need the target to be seen by bjam, so that the dependency from
            # sources to this generated header is detected -- if Jam does not
            # know about this target, it won't do anything.
            DEPENDS all : [ $(r).actualize ] ;

            return $(r) ;
        }
    }
}


# Query the installation directory. This is needed in at least two scenarios.
# First, when re-using sources from the Qt-Tree. Second, to "install" custom Qt
# plugins to the Qt-Tree.
#
rule directory
{
    return $(.prefix) ;
}

# -f forces moc to include the processed source file. Without it, it would think
# that .qpp is not a header and would not include it from the generated file.
#
actions moc
{
    $(.prefix)/bin/moc -f $(>) -o $(<)
}

# When moccing .cpp files, we don't need -f, otherwise generated code will
# include .cpp and we'll get duplicated symbols.
#
actions moc.cpp
{
    $(.prefix)/bin/moc $(>) -o $(<)
}


space = " " ;

# Sometimes it's required to make 'plugins' available during uic invocation. To
# help with this we add paths to all dependency libraries to uic commane line.
# The intention is that it's possible to write
#
#     exe a : ... a.ui ... : <uses>some_plugin ;
#
# and have everything work. We'd add quite a bunch of unrelated paths but it
# won't hurt.
#
flags qt3.uic-h LIBRARY_PATH <xdll-path> ;
actions uic-h
{
    $(.prefix)/bin/uic $(>) -o $(<) -L$(space)$(LIBRARY_PATH)
}


flags qt3.uic-cpp LIBRARY_PATH <xdll-path> ;
# The second target is uic-generated header name. It's placed in build dir, but
# we want to include it using only basename.
actions uic-cpp
{
    $(.prefix)/bin/uic $(>[1]) -i $(>[2]:D=) -o $(<) -L$(space)$(LIBRARY_PATH)
}
