"""
Tools for building F2PY generated extension modules.

-----
Permission to use, modify, and distribute this software is given under the
terms of the NumPy License. See http://scipy.org.

NO WARRANTY IS EXPRESSED OR IMPLIED.  USE AT YOUR OWN RISK.
Author: Pearu Peterson <pearu@cens.ioc.ee>
Created: Oct 2006
-----
"""

import os
import re
import sys
import tempfile

try:
    from numpy import __version__ as numpy_version
except ImportError:
    numpy_version = 'N/A'

__all__ = ['main']

__usage__ = """
F2PY G3 --- The third generation of Fortran to Python Interface Generator
=========================================================================

Description
-----------

f2py program generates a Python C/API file (<modulename>module.c) that
contains wrappers for given Fortran functions and data so that they
can be accessed from Python. With the -c option the corresponding
extension modules are built.

Options
-------

  --3g-numpy       Use numpy.f2py.lib tool, the 3rd generation of F2PY,
                   with NumPy support.
  --2d-numpy       Use numpy.f2py tool with NumPy support. [DEFAULT]
  --2d-numeric     Use f2py2e tool with Numeric support.
  --2d-numarray    Use f2py2e tool with Numarray support.

"""

import re
import shutil
from parser.api import parse, PythonModule, EndStatement, Module, Subroutine, Function

def get_values(sys_argv, prefix='', suffix='', strip_prefix=False, strip_suffix=False):
    """
    Return a list of values with pattern
      <prefix><value><suffix>.
    The corresponding items will be removed from sys_argv.
    """
    match = re.compile(prefix + r'.*' + suffix + '\Z').match
    ret = [item for item in sys_argv if match(item)]
    [sys_argv.remove(item) for item in ret]
    if strip_prefix and prefix:
        i = len(prefix)
        ret = [item[i:] for item in ret]
    if strip_suffix and suffix:
        i = len(suffix)
        ret = [item[:-i] for item in ret]
    return ret

def get_option(sys_argv, option, default_return = None):
    """
    Return True if sys_argv has <option>.
    If <option> is not in sys_argv, return default_return.
    <option> (when present) will be removed from sys_argv.
    """
    try:
        i = sys_argv.index(option)
    except ValueError:
        return default_return
    del sys_argv[i]
    return True

def get_option_value(sys_argv, option, default_value = None, default_return = None):
    """
    Return <value> from
      sys_argv = [...,<option>,<value>,...]
    list.
    If <option> is the last element, return default_value.
    If <option> is not in sys_argv, return default_return.
    Both <option> and <value> (when present) will be removed from sys_argv.
    """
    try:
        i = sys_argv.index(option)
    except ValueError:
        return default_return
    if len(sys_argv)-1==i:
        del sys_argv[i]
        return default_value
    value = sys_argv[i+1]
    del sys_argv[i+1]
    del sys_argv[i]
    return value

def get_signature_output(sys_argv):
    return get_option_value(sys_argv,'-h','stdout')

def dump_signature(sys_argv):
    """ Read Fortran files and dump the signatures to file or stdout.
    XXX: Not well tested.
    """
    signature_output = get_signature_output(sys_argv)

    # initialize output stream
    if signature_output in ['stdout','stderr']:
        output_stream = getattr(sys, signature_output)
        modulename = get_option_value(sys_argv,'-m','untitled','unknown')
    else:
        name,ext = os.path.splitext(signature_output)
        if ext != '.pyf':
            signature_output += '.pyf'
        if os.path.isfile(signature_output):
            overwrite = get_option(sys_argv, '--overwrite-signature', False)
            if not overwrite:
                print >> sys.stderr, 'Signature file %r exists. Use --overwrite-signature to overwrite.' % (signature_output)
                sys.exit()
        modulename = get_option_value(sys_argv,'-m',os.path.basename(name),os.path.basename(name))
        output_stream = open(signature_output,'w')

    flag = 'file'
    file_names = [] 
    only_names = []
    skip_names = []
    options = []
    for word in sys_argv[1:]:
        if word=='': pass
        elif word=='only:': flag = 'only'
        elif word=='skip:': flag = 'skip'
        elif word==':': flag = 'file'
        elif word.startswith('--'): options.append(word)
        else:
            {'file': file_names,'only': only_names, 'skip': skip_names}[flag].append(word)

    if options:
        sys.stderr.write('Unused options: %s\n' % (', '.join(options)))

    output_stream.write('''!    -*- f90 -*-
! Note: the context of this file is case sensitive.
''')
    output_stream.write('PYTHON MODULE %s\n' % (module_name))
    output_stream.write('  INTERFACE\n\n')
    for filename in file_names:
        if not os.path.isfile(filename):
            sys.stderr.write('No or not a file %r. Skipping.\n' % (filename))
            continue
        sys.stderr.write('Parsing %r..\n' % (filename))
        block = parse(filename)
        output_stream.write('! File: %s, source mode = %r\n' % (filename, block.reader.mode))
        if block.content and isinstance(block.content[0],PythonModule):
            for subblock in block.content[0].content[0].content:
                if isinstance(subblock, EndStatement):
                    break
                output_stream.write(subblock.topyf('    ')+'\n')
        else:
            output_stream.write(block.topyf('    ')+'\n')
    output_stream.write('  END INTERFACE\n')
    output_stream.write('END PYTHON MODULE %s\n' % (module_name))
    
    if signature_output not in ['stdout','stderr']:
        output_stream.close()
    return

def build_extension(sys_argv):
    """
    Build wrappers to Fortran 90 modules and external subprograms.
    """
    modulename = get_option_value(sys_argv,'-m','untitled','unknown')

    build_dir = get_option_value('--build-dir','.',None)
    if build_dir is None:
        build_dir = tempfile.mktemp()
        clean_build_dir = True
    else:
        clean_build_dir = False
    if not os.path.exists(build_dir): os.makedirs(build_dir)

    include_dirs = get_values(sys_argv,'-I',strip_prefix=True)
    library_dirs = get_values(sys_argv,'-L',strip_prefix=True)
    libraries = get_values(sys_argv,'-l',strip_prefix=True)
    _define_macros = get_values(sys_argv,'-D',strip_prefix=True)
    undef_macros = get_values(sys_argv,'-U',strip_prefix=True)
    extra_objects = get_values(sys_argv,'','[.](o|a|so|dll|dynlib|sl)')

    define_macros = []
    for item in _define_macros:
        name_value = item.split('=',1)
        if len(name_value)==1:
            name_value.append(None)
        if len(name_value)==2:
            define_macros.append(tuple(name_value))
        else:
            print 'Invalid use of -D:',name_value

    pyf_files = get_values(sys_argv,'','[.]pyf')
    fortran_files = get_values(sys_argv,'','[.](f|f90|F90|F)')
    c_files = get_values(sys_argv,'','[.](c|cpp|C|CPP|c[+][+])')

    fc_flags = get_values(sys_argv,'--fcompiler=')

    options = get_values(sys_argv,'-')
    if options:
        sys.stderr.write('Unused options: %s\n' % (', '.join(options)))

    if pyf_files:
        parse_files = pyf_files
    else:
        parse_files = fortran_files + c_files

    f90_modules = []
    external_subprograms = []

    for filename in parse_files:
        if not os.path.isfile(filename):
            sys.stderr.write('No or not a file %r. Skipping.\n' % (filename))
            continue
        sys.stderr.write('Parsing %r..\n' % (filename))
        for block in parse(filename, include_dirs=include_dirs).content:
            if isinstance(block, Module):
                f90_modules.append(block)
            elif isinstance(block, (Subroutine, Function)):
                external_subprograms.append(block)
            else:
                sys.stderr.write("Unhandled structure: %r\n" % (block.__class__))

    from py_wrap import PythonWrapperModule
    def configuration(parent_package='', top_path=None):
        from numpy.distutils.misc_util import Configuration
        config = Configuration('',parent_package,top_path)
        flibname = modulename + '_fortran_f2py'
        if fortran_files:
            config.add_library(flibname,
                               sources = fortran_files)
            libraries.insert(0,flibname)

        for block in f90_modules:
            wrapper = PythonWrapperModule(block.name)
            wrapper.add(block)
            c_code = wrapper.c_code()
            f_code = wrapper.fortran_code()
            c_fn = os.path.join(build_dir,'%smodule.c' % (block.name))
            f_fn = os.path.join(build_dir,'%s_f_wrappers_f2py.f' % (block.name))
            f = open(c_fn,'w')
            f.write(c_code)
            f.close()
            f = open(f_fn,'w')
            f.write(f_code)
            f.close()
            f_lib = '%s_f_wrappers_f2py' % (block.name)
            config.add_library(f_lib,
                               sources = [f_fn])
            config.add_extension(block.name,
                                 sources=[c_fn] + c_files,
                                 libraries = [f_lib] + libraries,
                                 define_macros = define_macros,
                                 undef_macros = undef_macros,
                                 include_dirs = include_dirs,
                                 extra_objects = extra_objects,
                                 )
        if external_subprograms:
            wrapper = PythonWrapperModule(modulename)
            for block in external_subprograms:
                wrapper.add(block)
            c_code = wrapper.c_code()
            f_code = wrapper.fortran_code()
            c_fn = os.path.join(temp_dir,'%smodule.c' % (modulename))
            f_fn = os.path.join(temp_dir,'%s_f_wrappers_f2py.f' % (modulename))
            f = open(c_fn,'w')
            f.write(c_code)
            f.close()
            f = open(f_fn,'w')
            f.write(f_code)
            f.close()
            f_lib = '%s_f_wrappers_f2py' % (modulename)
            config.add_library(f_lib,
                               sources = [f_fn])
            config.add_extension(modulename,
                                 sources=[c_fn] + c_files,
                                 libraries = [f_lib] + libraries,
                                 define_macros = define_macros,
                                 undef_macros = undef_macros,
                                 include_dirs = include_dirs,
                                 extra_objects = extra_objects,
                                 )
        return config

    old_sys_argv = sys.argv[:]
    new_sys_argv = [sys.argv[0]] + ['build',
                                   '--build-temp',build_dir,
                                   '--build-base',build_dir,
                                   '--build-platlib','.']
    if fc_flags:
        new_sys_argv += ['config_fc'] + fc_flags
    sys.argv[:] = new_sys_argv

    sys.stderr.write('setup arguments: %r\n' % (' '.join(sys.argv)))

    from numpy.distutils.core import setup
    setup(configuration=configuration)

    sys.argv[:] = old_sys_argv

    if clean_build_dir and os.path.exists(build_dir):
        sys.stderr.write('Removing build directory %s\n'%(build_dir))
        shutil.rmtree(build_dir)
    return

def main(sys_argv = None):
    """ Main function of f2py script.
    """
    if sys_argv is None:
        sys_argv = sys.argv[1:]
    if '--help-link' in sys_argv:
        sys_argv.remove('--help-link')
        from numpy.distutils.system_info import show_all
        show_all()
        return
    if '-c' in sys_argv:
        sys_argv.remove('-c')
        build_extension(sys_argv)
        return
    if '-h' in sys_argv:
        dump_signature(sys_argv)
        return
    print >> sys.stdout, __usage__