""" Build swig and f2py sources.
"""
import os
import re
import sys
import shlex
import copy

from distutils.command import build_ext
from distutils.dep_util import newer_group, newer
from distutils.util import get_platform
from distutils.errors import DistutilsError, DistutilsSetupError


# this import can't be done here, as it uses numpy stuff only available
# after it's installed
#import numpy.f2py
from numpy.distutils import log
from numpy.distutils.misc_util import (
    fortran_ext_match, appendpath, is_string, is_sequence, get_cmd
    )
from numpy.distutils.from_template import process_file as process_f_file
from numpy.distutils.conv_template import process_file as process_c_file

def subst_vars(target, source, d):
    """Substitute any occurrence of @foo@ by d['foo'] from source file into
    target."""
    var = re.compile('@([a-zA-Z_]+)@')
    with open(source, 'r') as fs:
        with open(target, 'w') as ft:
            for l in fs:
                m = var.search(l)
                if m:
                    ft.write(l.replace('@%s@' % m.group(1), d[m.group(1)]))
                else:
                    ft.write(l)

class build_src(build_ext.build_ext):

    description = "build sources from SWIG, F2PY files or a function"

    user_options = [
        ('build-src=', 'd', "directory to \"build\" sources to"),
        ('f2py-opts=', None, "list of f2py command line options"),
        ('swig=', None, "path to the SWIG executable"),
        ('swig-opts=', None, "list of SWIG command line options"),
        ('swig-cpp', None, "make SWIG create C++ files (default is autodetected from sources)"),
        ('f2pyflags=', None, "additional flags to f2py (use --f2py-opts= instead)"), # obsolete
        ('swigflags=', None, "additional flags to swig (use --swig-opts= instead)"), # obsolete
        ('force', 'f', "forcibly build everything (ignore file timestamps)"),
        ('inplace', 'i',
         "ignore build-lib and put compiled extensions into the source " +
         "directory alongside your pure Python modules"),
        ('verbose-cfg', None,
         "change logging level from WARN to INFO which will show all " +
         "compiler output")
        ]

    boolean_options = ['force', 'inplace', 'verbose-cfg']

    help_options = []

    def initialize_options(self):
        self.extensions = None
        self.package = None
        self.py_modules = None
        self.py_modules_dict = None
        self.build_src = None
        self.build_lib = None
        self.build_base = None
        self.force = None
        self.inplace = None
        self.package_dir = None
        self.f2pyflags = None # obsolete
        self.f2py_opts = None
        self.swigflags = None # obsolete
        self.swig_opts = None
        self.swig_cpp = None
        self.swig = None
        self.verbose_cfg = None

    def finalize_options(self):
        self.set_undefined_options('build',
                                   ('build_base', 'build_base'),
                                   ('build_lib', 'build_lib'),
                                   ('force', 'force'))
        if self.package is None:
            self.package = self.distribution.ext_package
        self.extensions = self.distribution.ext_modules
        self.libraries = self.distribution.libraries or []
        self.py_modules = self.distribution.py_modules or []
        self.data_files = self.distribution.data_files or []

        if self.build_src is None:
            plat_specifier = ".{}-{}.{}".format(get_platform(), *sys.version_info[:2])
            self.build_src = os.path.join(self.build_base, 'src'+plat_specifier)

        # py_modules_dict is used in build_py.find_package_modules
        self.py_modules_dict = {}

        if self.f2pyflags:
            if self.f2py_opts:
                log.warn('ignoring --f2pyflags as --f2py-opts already used')
            else:
                self.f2py_opts = self.f2pyflags
            self.f2pyflags = None
        if self.f2py_opts is None:
            self.f2py_opts = []
        else:
            self.f2py_opts = shlex.split(self.f2py_opts)

        if self.swigflags:
            if self.swig_opts:
                log.warn('ignoring --swigflags as --swig-opts already used')
            else:
                self.swig_opts = self.swigflags
            self.swigflags = None

        if self.swig_opts is None:
            self.swig_opts = []
        else:
            self.swig_opts = shlex.split(self.swig_opts)

        # use options from build_ext command
        build_ext = self.get_finalized_command('build_ext')
        if self.inplace is None:
            self.inplace = build_ext.inplace
        if self.swig_cpp is None:
            self.swig_cpp = build_ext.swig_cpp
        for c in ['swig', 'swig_opt']:
            o = '--'+c.replace('_', '-')
            v = getattr(build_ext, c, None)
            if v:
                if getattr(self, c):
                    log.warn('both build_src and build_ext define %s option' % (o))
                else:
                    log.info('using "%s=%s" option from build_ext command' % (o, v))
                    setattr(self, c, v)

    def run(self):
        log.info("build_src")
        if not (self.extensions or self.libraries):
            return
        self.build_sources()

    def build_sources(self):

        if self.inplace:
            self.get_package_dir = \
                     self.get_finalized_command('build_py').get_package_dir

        self.build_py_modules_sources()

        for libname_info in self.libraries:
            self.build_library_sources(*libname_info)

        if self.extensions:
            self.check_extensions_list(self.extensions)

            for ext in self.extensions:
                self.build_extension_sources(ext)

        self.build_data_files_sources()
        self.build_npy_pkg_config()

    def build_data_files_sources(self):
        if not self.data_files:
            return
        log.info('building data_files sources')
        from numpy.distutils.misc_util import get_data_files
        new_data_files = []
        for data in self.data_files:
            if isinstance(data, str):
                new_data_files.append(data)
            elif isinstance(data, tuple):
                d, files = data
                if self.inplace:
                    build_dir = self.get_package_dir('.'.join(d.split(os.sep)))
                else:
                    build_dir = os.path.join(self.build_src, d)
                funcs = [f for f in files if hasattr(f, '__call__')]
                files = [f for f in files if not hasattr(f, '__call__')]
                for f in funcs:
                    if f.__code__.co_argcount==1:
                        s = f(build_dir)
                    else:
                        s = f()
                    if s is not None:
                        if isinstance(s, list):
                            files.extend(s)
                        elif isinstance(s, str):
                            files.append(s)
                        else:
                            raise TypeError(repr(s))
                filenames = get_data_files((d, files))
                new_data_files.append((d, filenames))
            else:
                raise TypeError(repr(data))
        self.data_files[:] = new_data_files


    def _build_npy_pkg_config(self, info, gd):
        template, install_dir, subst_dict = info
        template_dir = os.path.dirname(template)
        for k, v in gd.items():
            subst_dict[k] = v

        if self.inplace == 1:
            generated_dir = os.path.join(template_dir, install_dir)
        else:
            generated_dir = os.path.join(self.build_src, template_dir,
                    install_dir)
        generated = os.path.basename(os.path.splitext(template)[0])
        generated_path = os.path.join(generated_dir, generated)
        if not os.path.exists(generated_dir):
            os.makedirs(generated_dir)

        subst_vars(generated_path, template, subst_dict)

        # Where to install relatively to install prefix
        full_install_dir = os.path.join(template_dir, install_dir)
        return full_install_dir, generated_path

    def build_npy_pkg_config(self):
        log.info('build_src: building npy-pkg config files')

        # XXX: another ugly workaround to circumvent distutils brain damage. We
        # need the install prefix here, but finalizing the options of the
        # install command when only building sources cause error. Instead, we
        # copy the install command instance, and finalize the copy so that it
        # does not disrupt how distutils want to do things when with the
        # original install command instance.
        install_cmd = copy.copy(get_cmd('install'))
        if not install_cmd.finalized == 1:
            install_cmd.finalize_options()
        build_npkg = False
        if self.inplace == 1:
            top_prefix = '.'
            build_npkg = True
        elif hasattr(install_cmd, 'install_libbase'):
            top_prefix = install_cmd.install_libbase
            build_npkg = True

        if build_npkg:
            for pkg, infos in self.distribution.installed_pkg_config.items():
                pkg_path = self.distribution.package_dir[pkg]
                prefix = os.path.join(os.path.abspath(top_prefix), pkg_path)
                d = {'prefix': prefix}
                for info in infos:
                    install_dir, generated = self._build_npy_pkg_config(info, d)
                    self.distribution.data_files.append((install_dir,
                        [generated]))

    def build_py_modules_sources(self):
        if not self.py_modules:
            return
        log.info('building py_modules sources')
        new_py_modules = []
        for source in self.py_modules:
            if is_sequence(source) and len(source)==3:
                package, module_base, source = source
                if self.inplace:
                    build_dir = self.get_package_dir(package)
                else:
                    build_dir = os.path.join(self.build_src,
                                             os.path.join(*package.split('.')))
                if hasattr(source, '__call__'):
                    target = os.path.join(build_dir, module_base + '.py')
                    source = source(target)
                if source is None:
                    continue
                modules = [(package, module_base, source)]
                if package not in self.py_modules_dict:
                    self.py_modules_dict[package] = []
                self.py_modules_dict[package] += modules
            else:
                new_py_modules.append(source)
        self.py_modules[:] = new_py_modules

    def build_library_sources(self, lib_name, build_info):
        sources = list(build_info.get('sources', []))

        if not sources:
            return

        log.info('building library "%s" sources' % (lib_name))

        sources = self.generate_sources(sources, (lib_name, build_info))

        sources = self.template_sources(sources, (lib_name, build_info))

        sources, h_files = self.filter_h_files(sources)

        if h_files:
            log.info('%s - nothing done with h_files = %s',
                     self.package, h_files)

        #for f in h_files:
        #    self.distribution.headers.append((lib_name,f))

        build_info['sources'] = sources
        return

    def build_extension_sources(self, ext):

        sources = list(ext.sources)

        log.info('building extension "%s" sources' % (ext.name))

        fullname = self.get_ext_fullname(ext.name)

        modpath = fullname.split('.')
        package = '.'.join(modpath[0:-1])

        if self.inplace:
            self.ext_target_dir = self.get_package_dir(package)

        sources = self.generate_sources(sources, ext)
        sources = self.template_sources(sources, ext)
        sources = self.swig_sources(sources, ext)
        sources = self.f2py_sources(sources, ext)
        sources = self.pyrex_sources(sources, ext)

        sources, py_files = self.filter_py_files(sources)

        if package not in self.py_modules_dict:
            self.py_modules_dict[package] = []
        modules = []
        for f in py_files:
            module = os.path.splitext(os.path.basename(f))[0]
            modules.append((package, module, f))
        self.py_modules_dict[package] += modules

        sources, h_files = self.filter_h_files(sources)

        if h_files:
            log.info('%s - nothing done with h_files = %s',
                     package, h_files)
        #for f in h_files:
        #    self.distribution.headers.append((package,f))

        ext.sources = sources

    def generate_sources(self, sources, extension):
        new_sources = []