import os

import os.path

import Params

import Object

import sys

import pproc as subprocess

import shlex

import ccroot

# these are set from the main wscript file

APPNAME=None

VERSION=None

#

# The last part of the path name to use to find the regression traces tarball.

# path will be APPNAME + '-' + VERSION + REGRESSION_SUFFIX + TRACEBALL_SUFFIX,

# e.g., ns-3-dev-ref-traces.tar.bz2

#

TRACEBALL_SUFFIX = ".tar.bz2"

def get_command_template(*arguments):

    if Params.g_options.valgrind:

        if Params.g_options.command_template:

            Params.fatal("Options --command-template and --valgrind are conflicting")

        cmd = "valgrind --leak-check=full %s"

    else:

        cmd = Params.g_options.command_template or '%s'

    for arg in arguments:

        cmd = cmd + " " + arg

    return cmd

def find_program(program_name, env):

    launch_dir = os.path.abspath(Params.g_cwd_launch)

    found_programs = []

    for obj in Object.g_allobjs:

        if not getattr(obj, 'is_ns3_program', False):

            continue

        ## filter out programs not in the subtree starting at the launch dir

        if not (obj.path.abspath().startswith(launch_dir)

                or obj.path.abspath(env).startswith(launch_dir)):

            continue

        found_programs.append(obj.target)

        if obj.target == program_name:

            return obj

    raise ValueError("program '%s' not found; available programs are: %r"

                     % (program_name, found_programs))

def get_proc_env(os_env=None):

    env = Params.g_build.env_of_name('default')

    if sys.platform == 'linux2':

        pathvar = 'LD_LIBRARY_PATH'

    elif sys.platform == 'darwin':

        pathvar = 'DYLD_LIBRARY_PATH'

    elif sys.platform == 'win32':

        pathvar = 'PATH'

    elif sys.platform == 'cygwin':

        pathvar = 'PATH'

    elif sys.platform.startswith('freebsd'):

        pathvar = 'LD_LIBRARY_PATH'

    else:

        Params.warning(("Don't know how to configure "

                        "dynamic library path for the platform %r;"

                        " assuming it's LD_LIBRARY_PATH.") % (sys.platform,))

        pathvar = 'LD_LIBRARY_PATH'        

    proc_env = dict(os.environ)

    if os_env is not None:

        proc_env.update(os_env)

    if pathvar is not None:

        if pathvar in proc_env:

            proc_env[pathvar] = os.pathsep.join(list(env['NS3_MODULE_PATH']) + [proc_env[pathvar]])

        else:

            proc_env[pathvar] = os.pathsep.join(list(env['NS3_MODULE_PATH']))

    pymoddir = Params.g_build.m_curdirnode.find_dir('bindings/python').abspath(env)

    if 'PYTHONPATH' in proc_env:

        proc_env['PYTHONPATH'] = os.pathsep.join([pymoddir] + [proc_env['PYTHONPATH']])

    else:

        proc_env['PYTHONPATH'] = pymoddir

    return proc_env

def run_argv(argv, os_env=None):

    proc_env = get_proc_env(os_env)

    #env = Params.g_build.env_of_name('default')

    retval = subprocess.Popen(argv, env=proc_env).wait()

    if retval:

        Params.fatal("Command %s exited with code %i" % (argv, retval))

    return retval

def get_run_program(program_string, command_template=None):

    """

    Return the program name and argv of the process that would be executed by

    run_program(program_string, command_template).

    """

    #print "get_run_program_argv(program_string=%r, command_template=%r)" % (program_string, command_template)

    env = Params.g_build.env_of_name('default')

    if command_template in (None, '%s'):

        argv = shlex.split(program_string)

        program_name = argv[0]

        try:

            program_obj = find_program(program_name, env)

        except ValueError, ex:

            Params.fatal(str(ex))

        try:

            program_node = program_obj.path.find_build(ccroot.get_target_name(program_obj))

        except AttributeError:

            Params.fatal("%s does not appear to be a program" % (program_name,))

        execvec = [program_node.abspath(env)] + argv[1:]

    else:

        program_name = program_string

        try:

            program_obj = find_program(program_name, env)

        except ValueError, ex:

            Params.fatal(str(ex))

        try:

            program_node = program_obj.path.find_build(ccroot.get_target_name(program_obj))

        except AttributeError:

            Params.fatal("%s does not appear to be a program" % (program_name,))

        execvec = shlex.split(command_template % (program_node.abspath(env),))

    return program_name, execvec

def run_program(program_string, command_template=None):

    """

    if command_template is not None, then program_string == program

    name and argv is given by command_template with %s replaced by the

    full path to the program.  Else, program_string is interpreted as

    a shell command with first name being the program name.

    """

    dummy_program_name, execvec = get_run_program(program_string, command_template)

    former_cwd = os.getcwd()

    if (Params.g_options.cwd_launch):

        os.chdir(Params.g_options.cwd_launch)

    else:

        os.chdir(Params.g_cwd_launch)

    try:

        retval = run_argv(execvec)

    finally:

        os.chdir(former_cwd)

    return retval

def run_python_program(program_string):

    env = Params.g_build.env_of_name('default')

    execvec = shlex.split(program_string)

    former_cwd = os.getcwd()

    if (Params.g_options.cwd_launch):

        os.chdir(Params.g_options.cwd_launch)

    else:

        os.chdir(Params.g_cwd_launch)

    try:

        retval = run_argv([env['PYTHON']] + execvec)

    finally:

        os.chdir(former_cwd)

    return retval