# -*- mode: python; coding: utf-8; -*-

#  Codezero -- a microkernel for embedded systems.
#
#  Copyright © 2009  B Labs Ltd
#
#  This program is free software: you can redistribute it and/or modify it under the terms of the GNU
#  General Public License as published by the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
#  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
#  License for more details.
#
#  You should have received a copy of the GNU General Public License along with this program.  If not, see
#  <http://www.gnu.org/licenses/>.
#
#  Author: Russel Winder

Import('environment', 'startAxf')

posixServicesDirectory = 'posix'

compilationProducts = []

##########  Build the task libraries ########################

taskSupportLibraryEnvironment = environment.Clone()
taskSupportLibraryEnvironment.Append(CPPPATH = ['#' + environment['buildDirectory'], '#' + environment['buildDirectory'] + '/l4', '#' + environment['includeDirectory']])

taskSupportLibraryEnvironment['posixServicesDirectory'] = 'containers/' + posixServicesDirectory

taskLibraryNames = [f.name for f in Glob(posixServicesDirectory + '/lib*')]

taskLibraries = []
for library in taskLibraryNames:
    taskLibraries.append(SConscript(posixServicesDirectory + '/' + library + '/SConscript', exports = {'environment': taskSupportLibraryEnvironment}))

Alias ('tasklibs', taskLibraries)
environment['targetHelpEntries']['tasklibs'] = 'build the support libraries for the tasks in the containers.'

##########  Build the tasks ########################

def buildTask(programName, sources, environment, previousImage, extraCppPath=None):
    e = environment.Clone()
    e.Append(LINKFLAGS=['-T' + e['posixServicesDirectory'] + '/' + programName + '/linker.lds'])
    e.Append(LIBPATH=['#' + e['buildDirectory'] + '/' + e['posixServicesDirectory'] + '/' + programName])
    if extraCppPath: e.Append(CPPPATH=extraCppPath)
    objects = e.StaticObject(sources)
    Depends(objects, e['configFiles'])
    program = e.Program(programName, objects)
    environment['physicalBaseLinkerScript'] = Command('physical_base.lds', previousImage, 'tools/pyelf/readelf.py --first-free-page ' + previousImage[0].path + ' >> $TARGET')
    Depends(program, environment['physicalBaseLinkerScript'])
    return program

tasksEnvironment = environment.Clone()
tasksEnvironment.Append(LIBS =  taskLibraries + ['gcc'] + taskLibraries)
tasksEnvironment.Append(CPPDEFINES = ['__USERSPACE__'])
tasksEnvironment.Append(CPPPATH = ['#' + environment['buildDirectory'], '#' + environment['buildDirectory'] + '/l4', '#' + environment['includeDirectory'], 'include', \
                                   '#containers/' +posixServicesDirectory + '/libl4/include', '#containers/' + posixServicesDirectory + '/libc/include', \
                                   '#containers/' + posixServicesDirectory + '/libmem', '#containers/' + posixServicesDirectory + '/libposix/include'])
tasksEnvironment.Append(buildTask = buildTask)
tasksEnvironment['posixServicesDirectory'] = 'containers/' + posixServicesDirectory

####
####  TODO: Why does the linker require crt0.o to be in the current directory and named as such.  Is it
####  because of the text in the linker script?
####

## If the ordering of tasks is not important then we should just be able to pull in all non-library
## directories that are not bootdesc.  If there needs to be a policy then either the directory names need to
## provide an order or a policy file presenting an order is needed.  For now we have a policy file.  Since
## we need to guarantee the ordering across many containers and many builds.

## taskNameList = [ f.name for f in Glob(posixServicesDirectory + '*') if f.name not in taskLibraryNames + ['bootdesc'] ]
## imageOrderData = [(taskName, []) for taskName in taskNameList]

#  To get the policy file, we have to know the build is being executed in the build/containers directory,
#  and that we can't use '#' as this is Python not SCons.

####
####  TODO: Task order (mm0, fs0, test0) works, but no other order does.  This implies a bug in the SCons
####  code.
####

execfile('../../containers/' + posixServicesDirectory + '/taskOrder.py')

imageOrderData = [(taskName, []) for taskName in taskOrder]
imageOrderData[0][1].append(startAxf)
tasks = []
for i in range(len(imageOrderData)):
    taskName = imageOrderData[i][0]
    dependency = imageOrderData[i][1]
    program = SConscript(posixServicesDirectory + '/' + taskName + '/SConscript', exports = {'environment': tasksEnvironment, 'previousImage': dependency[0]})
    tasks.append(program)
    if i < len(imageOrderData) - 1:
        imageOrderData[i+1][1].append(program)
        
Alias ('tasks', tasks)
environment['targetHelpEntries']['tasks'] = 'build the tasks for the containers.'

##########  Create the boot description ########################

bootdescEnvironment = environment.Clone()

bootdescEnvironment['posixServicesDirectory'] = 'containers/' + posixServicesDirectory

bootdesc = SConscript(posixServicesDirectory + '/bootdesc/SConscript', exports = {'environment': bootdescEnvironment, 'images': [startAxf] + tasks})

Alias('bootdesc', bootdesc)
environment['targetHelpEntries']['bootdesc'] = 'build the boot descriptions of the tasks for the containers.'

compilationProducts = tasks + [bootdesc]

Return('compilationProducts')