import os
import tempfile

from ansible.compat.tests import unittest
from ansible.module_utils._text import to_bytes

from ansible.modules.system.known_hosts import compute_diff


class KnownHostsDiffTestCase(unittest.TestCase):

    def _create_file(self, content):
        tmp_file = tempfile.NamedTemporaryFile(prefix='ansible-test-', suffix='-known_hosts', delete=False)
        tmp_file.write(to_bytes(content))
        tmp_file.close()
        self.addCleanup(os.unlink, tmp_file.name)
        return tmp_file.name

    def test_no_existing_file(self):
        path = tempfile.mktemp(prefix='ansible-test-', suffix='-known_hosts')
        key = 'example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=None, replace_or_add=False, state='present', key=key)
        self.assertEqual(diff, {
            'before_header': '/dev/null',
            'after_header': path,
            'before': '',
            'after': 'example.com ssh-rsa AAAAetc\n',
        })

    def test_key_addition(self):
        path = self._create_file(
            'two.example.com ssh-rsa BBBBetc\n'
        )
        key = 'one.example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=None, replace_or_add=False, state='present', key=key)
        self.assertEqual(diff, {
            'before_header': path,
            'after_header': path,
            'before':
                'two.example.com ssh-rsa BBBBetc\n',
            'after':
                'two.example.com ssh-rsa BBBBetc\n'
                'one.example.com ssh-rsa AAAAetc\n',
        })

    def test_no_change(self):
        path = self._create_file(
            'one.example.com ssh-rsa AAAAetc\n'
            'two.example.com ssh-rsa BBBBetc\n'
        )
        key = 'one.example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=1, replace_or_add=False, state='present', key=key)
        self.assertEqual(diff, {
            'before_header': path,
            'after_header': path,
            'before':
                'one.example.com ssh-rsa AAAAetc\n'
                'two.example.com ssh-rsa BBBBetc\n',
            'after':
                'one.example.com ssh-rsa AAAAetc\n'
                'two.example.com ssh-rsa BBBBetc\n',
        })

    def test_key_change(self):
        path = self._create_file(
            'one.example.com ssh-rsa AAAaetc\n'
            'two.example.com ssh-rsa BBBBetc\n'
        )
        key = 'one.example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=1, replace_or_add=True, state='present', key=key)
        self.assertEqual(diff, {
            'before_header': path,
            'after_header': path,
            'before':
                'one.example.com ssh-rsa AAAaetc\n'
                'two.example.com ssh-rsa BBBBetc\n',
            'after':
                'two.example.com ssh-rsa BBBBetc\n'
                'one.example.com ssh-rsa AAAAetc\n',
        })

    def test_key_removal(self):
        path = self._create_file(
            'one.example.com ssh-rsa AAAAetc\n'
            'two.example.com ssh-rsa BBBBetc\n'
        )
        key = 'one.example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=1, replace_or_add=False, state='absent', key=key)
        self.assertEqual(diff, {
            'before_header': path,
            'after_header': path,
            'before':
                'one.example.com ssh-rsa AAAAetc\n'
                'two.example.com ssh-rsa BBBBetc\n',
            'after':
                'two.example.com ssh-rsa BBBBetc\n',
        })

    def test_key_removal_no_change(self):
        path = self._create_file(
            'two.example.com ssh-rsa BBBBetc\n'
        )
        key = 'one.example.com ssh-rsa AAAAetc\n'
        diff = compute_diff(path, found_line=None, replace_or_add=False, state='absent', key=key)
        self.assertEqual(diff, {
            'before_header': path,
            'after_header': path,
            'before':
                'two.example.com ssh-rsa BBBBetc\n',
            'after':
                'two.example.com ssh-rsa BBBBetc\n',
        })