#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright 2019, Data61, CSIRO (ABN 41 687 119 230)
#
# SPDX-License-Identifier: BSD-2-Clause
#
#

'''
This file contains unit test cases related to the template macros.
'''

from __future__ import absolute_import, division, print_function, \
    unicode_literals

import ast, fnmatch, os, re, subprocess, sys, unittest

ME = os.path.abspath(__file__)
MY_DIR = os.path.dirname(ME)

# Make CapDL importable. Note that we just assume where it is in relation to
# our own directory.
sys.path.append(os.path.join(MY_DIR, '../../../../python-capdl'))

# Make CAmkES importable
sys.path.append(os.path.join(MY_DIR, '../../..'))

from camkes.internal.tests.utils import CAmkESTest, which
from camkes.templates.macros import NO_CHECK_UNUSED, get_perm
from camkes.templates import TemplateError

def uname():
    '''
    Determine the hardware architecture of this machine. Note that we're only
    really interested in x86 or x86_64.
    '''
    try:
        machine = subprocess.check_output(['uname', '-m']).strip()
    except subprocess.CalledProcessError:
        return None
    if re.match(r'i\d86$', machine):
        return 'x86'
    return machine

class TestMacros(CAmkESTest):

    def test_get_perm(self):
        conf = {}
        instance = "bah"
        iface = "humbug"
        field = '%s_access' % iface
        conf[instance] = {}

        self.assertEqual(get_perm(conf, instance, iface), "RWXP")
        conf[instance][field] = "R"
        self.assertEqual(get_perm(conf, instance, iface), "R")
        conf[instance][field] = "FOO"
        with self.assertRaises(TemplateError):
            get_perm(conf, instance, iface)

    def test_find_unused_macros(self):
        '''
        Find macros intended for the templates that are never actually used in
        any template.
        '''

        # First obtain a set of available macros by parsing the source of
        # macros.py.
        macrospy = os.path.join(MY_DIR, '../macros.py')
        with open(macrospy) as f:
            source = f.read()

        node = ast.parse(source, filename=macrospy)

        macros = set()
        for i in ast.iter_child_nodes(node):
            if isinstance(i, ast.FunctionDef):
                macros.add(i.name)

        # Next get a set of gitignored globs.

        # First up, ignore the tests.
        ignored = set(('%s/**' % MY_DIR,))

        # Now look at all .gitignores from three directories up.
        for stem in ('../../..', '../..', '..'):
            gitignore = os.path.join(MY_DIR, stem, '.gitignore')
            if os.path.exists(gitignore):
                with open(gitignore) as f:
                    for line in (x.strip() for x in f
                            if x.strip() != '' and not x.startswith('#')):
                        pattern = os.path.join(os.path.abspath(
                            os.path.dirname(gitignore)), line)
                        ignored.add(pattern)

        # Now let's look at all the templates and note macro calls.

        # A regex to match macro calls from the template context. Note that it is
        # imprecise, so the resulting analysis could generate false negatives.
        call = re.compile(r'/\*[-\?].*?\bmacros\.([a-zA-Z][a-zA-Z0-9_]*)\b')

        used = set()
        for root, _, files in os.walk(os.path.abspath(
                os.path.join(MY_DIR, '..'))):
            for f in (os.path.join(root, f) for f in files):
                for pattern in ignored:
                    try:
                        if fnmatch.fnmatchcase(f, pattern):
                            break
                    except Exception:
                        # Suppress any errors resulting from invalid lines in
                        # .gitignore.
                        pass
                else:
                    # This file did not match any of the ignore patterns; scan
                    # it for macro calls.

                    with open(f) as input:
                        source = input.read()
                    for m in call.finditer(source):
                        used.add(m.group(1))

        unused = macros - used - NO_CHECK_UNUSED
        if len(unused) > 0:
            [print("Unused macro: %s" % u) for u in unused]
        self.assertSetEqual(unused, set())

if __name__ == '__main__':
    unittest.main()