# MIT License
#
# Copyright The SCons Foundation
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

"""Tool-specific initialization for swig.

There normally shouldn't be any need to import this module directly.
It will usually be imported through the generic SCons.Tool.Tool()
selection method.
"""

import os.path
import re
import sys
from subprocess import PIPE

import SCons.Action
import SCons.Defaults
import SCons.Node
import SCons.Tool
import SCons.Util
import SCons.Warnings

verbose = False

swigs = [ 'swig', 'swig3.0', 'swig2.0' ]

SwigAction = SCons.Action.Action('$SWIGCOM', '$SWIGCOMSTR')

def swigSuffixEmitter(env, source) -> str:
    if '-c++' in SCons.Util.CLVar(env.subst("$SWIGFLAGS", source=source)):
        return '$SWIGCXXFILESUFFIX'
    else:
        return '$SWIGCFILESUFFIX'

# Match '%module test', as well as '%module(directors="1") test'
# Also allow for test to be quoted (SWIG permits double quotes, but not single)
# Also allow for the line to have spaces after test if not quoted
_reModule = re.compile(r'%module(\s*\(.*\))?\s+("?)(\S+)\2')

def _find_modules(src):
    """Find all modules referenced by %module lines in `src`, a SWIG .i file.
       Returns a list of all modules, and a flag set if SWIG directors have
       been requested (SWIG will generate an additional header file in this
       case.)"""
    directors = 0
    mnames = []
    try:
        with open(src) as f:
            data = f.read()
        matches = _reModule.findall(data)
    except OSError:
        # If the file's not yet generated, guess the module name from the file stem
        matches = []
        mnames.append(os.path.splitext(os.path.basename(src))[0])

    for m in matches:
        mnames.append(m[2])
        directors = directors or 'directors' in m[0]
    return mnames, directors

def _add_director_header_targets(target, env) -> None:
    # Directors only work with C++ code, not C
    suffix = env.subst(env['SWIGCXXFILESUFFIX'])
    # For each file ending in SWIGCXXFILESUFFIX, add a new target director
    # header by replacing the ending with SWIGDIRECTORSUFFIX.
    for x in target[:]:
        n = x.name
        d = x.dir
        if n[-len(suffix):] == suffix:
            target.append(d.File(n[:-len(suffix)] + env['SWIGDIRECTORSUFFIX']))

def _swigEmitter(target, source, env):
    swigflags = env.subst("$SWIGFLAGS", target=target, source=source)
    flags = SCons.Util.CLVar(swigflags)
    for src in source:
        src = str(src.rfile())
        mnames = None
        if "-python" in flags and "-noproxy" not in flags:
            if mnames is None:
                mnames, directors = _find_modules(src)
            if directors:
                _add_director_header_targets(target, env)
            python_files = [m + ".py" for m in mnames]
            outdir = env.subst('$SWIGOUTDIR', target=target, source=source)
            # .py files should be generated in SWIGOUTDIR if specified,
            # otherwise in the same directory as the target
            if outdir:
                python_files = [env.fs.File(os.path.join(outdir, j)) for j in python_files]
            else:
                python_files = [target[0].dir.File(m) for m in python_files]
            target.extend(python_files)
        if "-java" in flags:
            if mnames is None:
                mnames, directors = _find_modules(src)
            if directors:
                _add_director_header_targets(target, env)
            java_files = [[m + ".java", m + "JNI.java"] for m in mnames]
            java_files = SCons.Util.flatten(java_files)
            outdir = env.subst('$SWIGOUTDIR', target=target, source=source)
            if outdir:
                 java_files = [os.path.join(outdir, j) for j in java_files]
            java_files = list(map(env.fs.File, java_files))
            def t_from_s(t, p, s, x):
                return t.dir
            tsm = SCons.Node._target_from_source_map
            tkey = len(tsm)
            tsm[tkey] = t_from_s
            for jf in java_files:
                jf._func_target_from_source = tkey
            target.extend(java_files)
    return (target, source)

def _get_swig_version(env, swig):
    """Run the SWIG command line tool to get and return the version number"""
    version = None
    swig = env.subst(swig)
    if not swig:
        return version

    cp = SCons.Action.scons_subproc_run(
        env, SCons.Util.CLVar(swig) + ['-version'], stdout=PIPE
    )
    if cp.returncode:
        return version
    out = SCons.Util.to_str(cp.stdout)
    match = re.search(r'SWIG Version\s+(\S+).*', out, re.MULTILINE)
    if match:
        version = match.group(1)
        if verbose:
            print("Version is: %s" % version)
    else:
        if verbose:
            print("Unable to detect version: [%s]" % out)

    return version

def generate(env) -> None:
    """Add Builders and construction variables for swig to an Environment."""
    c_file, cxx_file = SCons.Tool.createCFileBuilders(env)

    c_file.suffix['.i'] = swigSuffixEmitter
    cxx_file.suffix['.i'] = swigSuffixEmitter

    c_file.add_action('.i', SwigAction)
    c_file.add_emitter('.i', _swigEmitter)
    cxx_file.add_action('.i', SwigAction)
    cxx_file.add_emitter('.i', _swigEmitter)

    java_file = SCons.Tool.CreateJavaFileBuilder(env)

    java_file.suffix['.i'] = swigSuffixEmitter

    java_file.add_action('.i', SwigAction)
    java_file.add_emitter('.i', _swigEmitter)

    from SCons.Platform.mingw import MINGW_DEFAULT_PATHS
    from SCons.Platform.cygwin import CYGWIN_DEFAULT_PATHS
    from SCons.Platform.win32 import CHOCO_DEFAULT_PATH

    if sys.platform == 'win32':
        swig = SCons.Tool.find_program_path(env, 'swig', default_paths=MINGW_DEFAULT_PATHS + CYGWIN_DEFAULT_PATHS + CHOCO_DEFAULT_PATH)
        if swig:
            swig_bin_dir = os.path.dirname(swig)
            env.AppendENVPath('PATH', swig_bin_dir)
        else:
            SCons.Warnings.warn(
                SCons.Warnings.SConsWarning,
                'swig tool requested, but binary not found in ENV PATH'
            )

    if 'SWIG' not in env:
        env['SWIG'] = env.Detect(swigs) or swigs[0]

    env['SWIGVERSION'] = _get_swig_version(env, env['SWIG'])
    env['SWIGFLAGS'] = SCons.Util.CLVar('')
    env['SWIGDIRECTORSUFFIX'] = '_wrap.h'
    env['SWIGCFILESUFFIX'] = '_wrap$CFILESUFFIX'
    env['SWIGCXXFILESUFFIX'] = '_wrap$CXXFILESUFFIX'
    env['_SWIGOUTDIR'] = r'${"-outdir \"%s\"" % SWIGOUTDIR}'
    env['SWIGPATH'] = []
    env['SWIGINCPREFIX'] = '-I'
    env['SWIGINCSUFFIX'] = ''
    env['_SWIGINCFLAGS'] = '${_concat(SWIGINCPREFIX, SWIGPATH, SWIGINCSUFFIX,' \
                            '__env__, RDirs, TARGET, SOURCE, affect_signature=False)}'
    env['SWIGCOM'] = '$SWIG -o $TARGET ${_SWIGOUTDIR} ${_SWIGINCFLAGS} $SWIGFLAGS $SOURCES'

def exists(env):
    swig = env.get('SWIG') or env.Detect(['swig'])
    return swig

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