## -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-

import re

import Params

import Configure

import Object

import Action

import os

import Task

import pproc as subprocess

from Params import fatal, warning

import shutil

## Adjust python path to look for our local copy of pybindgen

LOCAL_PYBINDGEN_PATH = os.path.join(os.getcwd(), "bindings", "python", "pybindgen")

#PYBINDGEN_BRANCH = 'lp:pybindgen'

PYBINDGEN_BRANCH = 'https://launchpad.net/pybindgen'

if os.environ.get('PYTHONPATH', ''):

    os.environ['PYTHONPATH'] = LOCAL_PYBINDGEN_PATH + os.pathsep + os.environ.get('PYTHONPATH')

else:

    os.environ['PYTHONPATH'] = LOCAL_PYBINDGEN_PATH

## https://launchpad.net/pybindgen/

REQUIRED_PYBINDGEN_VERSION = (0, 9, 0, 572)

REQUIRED_PYGCCXML_VERSION = (0, 9, 5)

def set_options(opt):

    opt.tool_options('python')

    opt.add_option('--python-disable',

                   help=("Don't build Python bindings."),

                   action="store_true", default=False,

                   dest='python_disable')

    opt.add_option('--python-scan',

                   help=("Rescan Python bindings.  Needs working GCCXML / pygccxml environment."),

                   action="store_true", default=False,

                   dest='python_scan')

    opt.add_option('--pybindgen-checkout',

                   help=("During configure, force checkout of pybingen inside ns-3, "

                         "instead of using the system installed version."),

                   action="store_true", default=False,

                   dest='pybindgen_checkout')

def fetch_pybindgen(conf):

    """

    Fetches pybindgen from launchpad as bindings/python/pybindgen.

    Returns True if successful, False it not.

    """

    bzr = conf.find_program("bzr")

    if not bzr:

        warning("the program 'bzr' is needed in order to fetch pybindgen")

        return False

    if len(REQUIRED_PYBINDGEN_VERSION) == 4:

        rev = "-rrevno:%i" % REQUIRED_PYBINDGEN_VERSION[3]

    else:

        rev = "-rtag:%s" % '.'.join([str(x) for x in REQUIRED_PYBINDGEN_VERSION])

    if os.path.exists(LOCAL_PYBINDGEN_PATH):

        print "Trying to update pybindgen; this will fail if no network connection is available."

        cmd = [bzr, "pull", rev, PYBINDGEN_BRANCH]

        print " => ", ' '.join(cmd)

        if subprocess.Popen(cmd, cwd=LOCAL_PYBINDGEN_PATH).wait():

            return False

        print "Update was successful."

    else:

        print "Trying to fetch pybindgen; this will fail if no network connection is available."

        cmd = [bzr, "checkout", rev, PYBINDGEN_BRANCH, LOCAL_PYBINDGEN_PATH]

        print " => ", ' '.join(cmd)

        if subprocess.Popen(cmd).wait():

            return False

        print "Fetch was successful."

    ## generate a fake version.py file in pybindgen it's safer this

    ## way, since the normal version generation process requires

    ## bazaar python bindings, which may not be available.

    vfile = open(os.path.join(LOCAL_PYBINDGEN_PATH, "pybindgen", "version.py"), "wt")

    vfile.write("""

# (fake version generated by ns-3)

__version__ = %r

""" % list(REQUIRED_PYBINDGEN_VERSION))

    vfile.close()

    return True

def configure(conf):

    conf.env['ENABLE_PYTHON_BINDINGS'] = False

    if Params.g_options.python_disable:

        return

    conf.check_tool('misc')

    ## Check for Python

    try:

        conf.check_tool('python')

        conf.check_python_version((2,3))

        conf.check_python_headers()

    except Configure.ConfigurationError:

        return

    ## Check for pybindgen

    if Params.g_options.pybindgen_checkout:

        fetch_pybindgen(conf)

    try:

        conf.check_python_module('pybindgen')

    except Configure.ConfigurationError:

        warning("pybindgen missing")

        if not fetch_pybindgen(conf):

            return

    else:

        out = subprocess.Popen([conf.env['PYTHON'], "-c",

                                "import pybindgen.version; "

                                "print '.'.join([str(x) for x in pybindgen.version.__version__])"],

                                stdout=subprocess.PIPE).communicate()[0]

        pybindgen_version_str = out.strip()

        pybindgen_version = tuple([int(x) for x in pybindgen_version_str.split('.')])

        conf.check_message('pybindgen', 'version',

                           (pybindgen_version >= REQUIRED_PYBINDGEN_VERSION),

                           pybindgen_version_str)

        if not (pybindgen_version >= REQUIRED_PYBINDGEN_VERSION):

            warning("pybindgen (found %s) is too old (need %s)" %

                    (pybindgen_version_str,

                     '.'.join([str(x) for x in REQUIRED_PYBINDGEN_VERSION])))

            if not fetch_pybindgen(conf):

                return

    ## If all has gone well, we finally enable the Python bindings

    conf.env['ENABLE_PYTHON_BINDINGS'] = True

    ## Check for pygccxml

    try:

        conf.check_python_module('pygccxml')

    except Configure.ConfigurationError:

        return

    out = subprocess.Popen([conf.env['PYTHON'], "-c",

                            "import pygccxml; print pygccxml.__version__"],

                            stdout=subprocess.PIPE).communicate()[0]

    pygccxml_version_str = out.strip()

    pygccxml_version = tuple([int(x) for x in pygccxml_version_str.split('.')])

    conf.check_message('pygccxml', 'version',

                       (pygccxml_version >= REQUIRED_PYGCCXML_VERSION),

                       pygccxml_version_str)

    if not (pygccxml_version >= REQUIRED_PYGCCXML_VERSION):

        warning("pygccxml (found %s) is too old (need %s) => "

                "automatic scanning of API definitions will not be possible" %

                (pygccxml_version_str,

                 '.'.join([str(x) for x in REQUIRED_PYGCCXML_VERSION])))

        return

    ## Check gccxml version

    gccxml = conf.find_program('gccxml', var='GCCXML')

    if not gccxml:

        warning("gccxml missing; automatic scanning of API definitions will not be possible")

        return

    gccxml_version_line = os.popen(gccxml + " --version").readline().strip()

    m = re.match( "^GCC-XML version (\d\.\d(\.\d)?)$", gccxml_version_line)

    gccxml_version = m.group(1)

    gccxml_version_ok = ([int(s) for s in gccxml_version.split('.')] >= [0, 9])

    conf.check_message('gccxml', 'version', True, gccxml_version)

    if not gccxml_version_ok:

        warning("gccxml too old, need version >= 0.9; automatic scanning of API definitions will not be possible")

        return

    ## If we reached

    conf.env['ENABLE_PYTHON_SCANNING'] = True

prio_headers = {

    -2: (

        "string.h", # work around http://www.gccxml.org/Bug/view.php?id=6682

        ),

    -1: (

        "propagation-delay-model.h",

        "propagation-loss-model.h",

        "net-device.h",

        )

     }

def get_header_prio(header):

    for prio, headers in prio_headers.iteritems():

        if header in headers:

            return prio

    return 1

def calc_header_include(path):

    (head, tail) = os.path.split (path)

    if tail == 'ns3':

        return ''

    else:

        return os.path.join (calc_header_include (head), tail)

def gen_ns3_metaheader(task):

    assert len(task.m_outputs) == 1

    header_files = [calc_header_include(node.abspath(task.m_env)) for node in task.m_inputs]

    outfile = file(task.m_outputs[0].bldpath(task.m_env), "w")

    def sort_func(h1, h2):

        return cmp((get_header_prio(h1), h1), (get_header_prio(h1), h2))

    header_files.sort(sort_func)

    for header in header_files:

        print >> outfile, "#include \"ns3/%s\"" % (header,)

    print >> outfile, """

namespace ns3 {

static inline Ptr<Object>

__dummy_function_to_force_template_instantiation (Ptr<Object> obj, TypeId typeId)

{

   return obj->GetObject<Object> (typeId);

}

}

"""

    outfile.close()

    return 0

class all_ns3_headers_taskgen(Object.task_gen):

    """Generates a 'everything.h' header file that includes some/all public ns3 headers.

    This single header file is to be parsed only once by gccxml, for greater efficiency.

    """

    def __init__(self, *features):

        Object.task_gen.__init__(self, *features)

        self.inst_var = 0#'INCLUDEDIR'

        #self.inst_dir = 'ns3'

    def apply(self):

        ## get all of the ns3 headers

        ns3_dir_node = Params.g_build.m_srcnode.find_dir("ns3")

        all_headers_inputs = []

        for filename in self.to_list(self.source):

            src_node = ns3_dir_node.find_build(filename)

            if src_node is None:

                Params.fatal("source ns3 header file %s not found" % (filename,))

            all_headers_inputs.append(src_node)

        ## if self.source was empty, include all ns3 headers in enabled modules

        if not all_headers_inputs:

            for ns3headers in Object.g_allobjs:

                if type(ns3headers).__name__ == 'ns3header_taskgen': # XXX: find less hackish way to compare

                    ## skip headers not part of enabled modules

                    if self.env['NS3_ENABLED_MODULES']:

                        if ("ns3-%s" % ns3headers.module) not in self.env['NS3_ENABLED_MODULES']:

                            continue

                    for source in ns3headers.to_list(ns3headers.source):

                        #source = os.path.basename(source)

                        node = ns3_dir_node.find_build(source)

                        if node is None:

                            fatal("missing header file %s" % (source,))

                        all_headers_inputs.append(node)

        assert all_headers_inputs

        all_headers_outputs = [self.path.find_build("everything.h")]

        task = self.create_task('gen-ns3-metaheader', self.env, 4)

        task.set_inputs(all_headers_inputs)

        task.set_outputs(all_headers_outputs)

    def install(self):

        pass

def get_modules_and_headers():

    """

    Gets a dict of

       module_name => ([module_dep1, module_dep2, ...], [module_header1, module_header2, ...])

    tuples, one for each module.

    """

    retval = {}

    for module in Object.g_allobjs:

        if not module.name.startswith('ns3-'):

            continue

        module_name = module.name[4:] # strip the ns3- prefix

        ## find the headers object for this module

        headers = []

        for ns3headers in Object.g_allobjs:

            if type(ns3headers).__name__ != 'ns3header_taskgen': # XXX: find less hackish way to compare

                continue

            if ns3headers.module != module_name:

                continue

            for source in ns3headers.to_list(ns3headers.source):

                headers.append(source)

        retval[module_name] = (list(module.module_deps), headers)

    return retval

class PythonScanTask(Task.TaskBase):

    """Uses gccxml to scan the file 'everything.h' and extract API definitions.

    """

    def __init__(self, curdirnode, env):

        self.m_display = 'python-scan'

        self.prio = 5 # everything.h has prio 4

        super(PythonScanTask, self).__init__()

        self.curdirnode = curdirnode

        self.env = env

    def run(self):

        #print "Rescanning the python bindings..."

        argv = [

            self.env['PYTHON'],

            os.path.join(self.curdirnode.abspath(), 'ns3modulescan.py'), # scanning script

            self.curdirnode.find_dir('../..').abspath(self.env), # include path (where the ns3 include dir is)

            self.curdirnode.find_build('everything.h').abspath(self.env),

            os.path.join(self.curdirnode.abspath(), 'ns3modulegen_generated.py'), # output file

            ]

        scan = subprocess.Popen(argv, stdin=subprocess.PIPE)

        scan.stdin.write(repr(get_modules_and_headers()))

        scan.stdin.close()

        if scan.wait():

            raise SystemExit(1)

def build(bld):

    if Params.g_options.python_disable:

        return

    env = bld.env_of_name('default')

    curdir = bld.m_curdirnode.abspath()

    #Object.register('all-ns3-headers', AllNs3Headers)

    Action.Action('gen-ns3-metaheader', func=gen_ns3_metaheader, color='BLUE')

    if env['ENABLE_PYTHON_BINDINGS']:

        obj = bld.create_obj('all_ns3_headers')

    if Params.g_options.python_scan:

        if not env['ENABLE_PYTHON_SCANNING']:

            Params.fatal("Cannot re-scan python bindings: (py)gccxml not available")

        PythonScanTask(bld.m_curdirnode, env)

    ## Get a list of scanned modules; the set of scanned modules

    ## may be smaller than the set of all modules, in case a new

    ## ns3 module is being developed which wasn't scanned yet.

    scanned_modules = []

    for filename in os.listdir(curdir):

        m = re.match(r"^ns3_module_(.+)\.py$", filename)

        if m is None:

            continue

        name = m.group(1)

        if name.endswith("__local"):

            continue

        scanned_modules.append(name)

    if env['ENABLE_PYTHON_BINDINGS']:

        bindgen = bld.create_obj('command-output')

        bindgen.name = 'pybindgen'

        bindgen.command = env['PYTHON']

        bindgen.command_is_external = True

        bindgen.stderr = 'ns3modulegen.log'

        bindgen.argv = [

            bindgen.input_file("ns3modulegen.py"),

            bindgen.output_file("ns3module.cc"),

            ]

        bindgen.argv.extend(get_modules_and_headers().iterkeys())

        bindgen.hidden_inputs = ['everything.h',

                                 'ns3modulegen_generated.py',

                                 'ns3modulegen_core_customizations.py']

        for module in scanned_modules:

            bindgen.hidden_inputs.append("ns3_module_%s.py" % module)

            local = "ns3_module_%s__local.py" % module

            if os.path.exists(os.path.join(curdir, local)):

                bindgen.hidden_inputs.append(local)

        bindgen.hidden_outputs = ['ns3module.h']

        for module in scanned_modules:

            bindgen.hidden_outputs.append("ns3_module_%s.cc" % module)

        bindgen.prio = 50

        bindgen.os_env = dict(os.environ)

        if not env['ENABLE_GTK_CONFIG_STORE']:

            bindgen.os_env['DISABLE_GTK_CONFIG_STORE'] = "1"

        if not env['SQLITE_STATS']:

            bindgen.os_env['SQLITE_STATS'] = "1"

    ## we build python bindings if either we have the tools to

    ## generate them or if the pregenerated source file is already

    ## present in the source dir.

    if env['ENABLE_PYTHON_BINDINGS'] \

            or os.path.exists(os.path.join(bld.m_curdirnode.abspath(), 'ns3module.cc')):

        pymod = bld.create_obj('cpp', 'shlib', 'pyext')

        pymod.source = ['ns3module.cc', 'ns3module_helpers.cc']

        pymod.includes = '.'

        for module in scanned_modules:

            pymod.source.append("ns3_module_%s.cc" % module)

        pymod.target = 'ns3/_ns3'

        pymod.name = 'ns3module'

        pymod.uselib_local = "ns3"

        pymod.env.append_value('CXXDEFINES', ['NS_DEPRECATED=""', 'NS3_DEPRECATED_H'])

        # copy the __init__.py file to the build dir waf can't handle

        # this, it's against waf's principles to have build dir files

        # with the same name as source dir files, apparently.

        dirnode = bld.m_curdirnode.find_dir('ns3')

        src = os.path.join(dirnode.abspath(), '__init__.py')

        dst = os.path.join(dirnode.abspath(env), '__init__.py')

        try:

            need_copy = os.stat(src).st_mtime > os.stat(dst).st_mtime

        except OSError:

            need_copy = True

        if need_copy:

            try:

                os.mkdir(os.path.dirname(dst))

            except OSError:

                pass

            print "%r -> %r" % (src, dst)

            shutil.copy2(src, dst)