import re
import os
import random
import sys
import unittest
from io import StringIO
import configparser
from iniparse import compat, ini, tidy

# TODO:
#  tabs
#  substitutions


def random_string(maxlen=200):
    length = random.randint(0, maxlen)
    s = []
    for i in range(length):
        s.append(chr(random.randint(32, 126)))

    return ''.join(s)


def random_space(maxlen=10):
    length = random.randint(0, maxlen)
    return ' '*length


def random_ini_file():
    num_lines = random.randint(0, 100)
    lines = []
    for i in range(num_lines):
        x = random.random()
        if x < 0.1:
            # empty line
            lines.append(random_space())
        elif x < 0.3:
            # comment
            sep = random.choice(['#', ';'])
            lines.append(sep + random_string())
        elif x < 0.5:
            # section
            if random.random() < 0.1:
                name = 'DEFAULT'
            else:
                name = random_string()
                name = re.sub(']', '' , name)
            l = '[' + name + ']'
            if random.randint(0,1):
                l += random_space()
            if random.randint(0,1):
                sep = random.choice(['#', ';'])
                l += sep + random_string()
            lines.append(l)
        elif x < 0.7:
            # option
            name = random_string()
            name = re.sub(':|=| |\[', '', name)
            sep = random.choice([':', '='])
            l = name + random_space() + sep + random_space() + random_string()
            if random.randint(0,1):
                l += ' ' + random_space() + ';'  +random_string()
            lines.append(l)
        elif x < 0.9:
            # continuation
            lines.append(' ' + random_space() + random_string())
        else:
            # junk
            lines.append(random_string())

    return '\n'.join(lines)


class TestFuzz(unittest.TestCase):
    def test_fuzz(self):
        random.seed(42)
        try:
            num_iter = int(os.environ['INIPARSE_FUZZ_ITERATIONS'])
        except (KeyError, ValueError):
            num_iter = 100
        for fuzz_iter in range(num_iter):
            try:
                # parse random file with errors disabled
                s = random_ini_file()
                c = ini.INIConfig(parse_exc=False)
                c._readfp(StringIO(s))
                # check that file is preserved, except for
                # commenting out erroneous lines
                l1 = s.split('\n')
                l2 = str(c).split('\n')
                self.assertEqual(len(l1), len(l2))
                good_lines = []
                for i in range(len(l1)):
                    try:
                        self.assertEqual(l1[i], l2[i])
                        good_lines.append(l1[i])
                    except AssertionError:
                        self.assertEqual('#'+l1[i], l2[i])
                # parse the good subset of the file
                # using ConfigParser
                s = '\n'.join(good_lines)
                cc = compat.RawConfigParser()
                cc.readfp(StringIO(s))
                cc_py = configparser.RawConfigParser()
                cc_py.read_file(StringIO(s))
                # compare the two configparsers
                self.assertEqualConfig(cc_py, cc)
                # check that tidy does not change semantics
                tidy(cc)
                cc_tidy = configparser.RawConfigParser()
                cc_tidy.readfp(StringIO(str(cc.data)))
                self.assertEqualConfig(cc_py, cc_tidy)
            except AssertionError:
                fname = 'fuzz-test-iter-%d.ini' % fuzz_iter
                print('Fuzz test failed at iteration', fuzz_iter)
                print('Writing out failing INI file as', fname)
                f = open(fname, 'w')
                f.write(s)
                f.close()
                raise

    @unittest.skipIf(sys.version_info[0] > 2, 'http://code.google.com/p/iniparse/issues/detail?id=22#c9')
    def assertEqualConfig(self, c1, c2):
        self.assertEqualSorted(c1.sections(), c2.sections())
        self.assertEqualSorted(c1.defaults().items(), c2.defaults().items())
        for sec in c1.sections():
            self.assertEqualSorted(c1.options(sec), c2.options(sec))
            for opt in c1.options(sec):
                self.assertEqual(c1.get(sec, opt), c2.get(sec, opt))

    def assertEqualSorted(self, l1, l2):
        self.assertEqual(sorted(l1), sorted(l2))