import os.path

from django.core.exceptions import ValidationError
from django.forms import FilePathField
from django.test import SimpleTestCase

PATH = os.path.dirname(os.path.abspath(__file__))


def fix_os_paths(x):
    if isinstance(x, str):
        if x.startswith(PATH):
            x = x[len(PATH):]
        return x.replace('\\', '/')
    elif isinstance(x, tuple):
        return tuple(fix_os_paths(list(x)))
    elif isinstance(x, list):
        return [fix_os_paths(y) for y in x]
    else:
        return x


class FilePathFieldTest(SimpleTestCase):
    expected_choices = [
        ('/filepathfield_test_dir/__init__.py', '__init__.py'),
        ('/filepathfield_test_dir/a.py', 'a.py'),
        ('/filepathfield_test_dir/ab.py', 'ab.py'),
        ('/filepathfield_test_dir/b.py', 'b.py'),
        ('/filepathfield_test_dir/c/__init__.py', '__init__.py'),
        ('/filepathfield_test_dir/c/d.py', 'd.py'),
        ('/filepathfield_test_dir/c/e.py', 'e.py'),
        ('/filepathfield_test_dir/c/f/__init__.py', '__init__.py'),
        ('/filepathfield_test_dir/c/f/g.py', 'g.py'),
        ('/filepathfield_test_dir/h/__init__.py', '__init__.py'),
        ('/filepathfield_test_dir/j/__init__.py', '__init__.py'),
    ]
    path = os.path.join(PATH, 'filepathfield_test_dir') + '/'

    def assertChoices(self, field, expected_choices):
        self.assertEqual(fix_os_paths(field.choices), expected_choices)

    def test_fix_os_paths(self):
        self.assertEqual(fix_os_paths(self.path), ('/filepathfield_test_dir/'))

    def test_nonexistent_path(self):
        with self.assertRaisesMessage(FileNotFoundError, 'nonexistent'):
            FilePathField(path='nonexistent')

    def test_no_options(self):
        f = FilePathField(path=self.path)
        expected = [
            ('/filepathfield_test_dir/README', 'README'),
        ] + self.expected_choices[:4]
        self.assertChoices(f, expected)

    def test_clean(self):
        f = FilePathField(path=self.path)
        msg = "'Select a valid choice. a.py is not one of the available choices.'"
        with self.assertRaisesMessage(ValidationError, msg):
            f.clean('a.py')
        self.assertEqual(fix_os_paths(f.clean(self.path + 'a.py')), '/filepathfield_test_dir/a.py')

    def test_match(self):
        f = FilePathField(path=self.path, match=r'^.*?\.py$')
        self.assertChoices(f, self.expected_choices[:4])

    def test_recursive(self):
        f = FilePathField(path=self.path, recursive=True, match=r'^.*?\.py$')
        expected = [
            ('/filepathfield_test_dir/__init__.py', '__init__.py'),
            ('/filepathfield_test_dir/a.py', 'a.py'),
            ('/filepathfield_test_dir/ab.py', 'ab.py'),
            ('/filepathfield_test_dir/b.py', 'b.py'),
            ('/filepathfield_test_dir/c/__init__.py', 'c/__init__.py'),
            ('/filepathfield_test_dir/c/d.py', 'c/d.py'),
            ('/filepathfield_test_dir/c/e.py', 'c/e.py'),
            ('/filepathfield_test_dir/c/f/__init__.py', 'c/f/__init__.py'),
            ('/filepathfield_test_dir/c/f/g.py', 'c/f/g.py'),
            ('/filepathfield_test_dir/h/__init__.py', 'h/__init__.py'),
            ('/filepathfield_test_dir/j/__init__.py', 'j/__init__.py'),

        ]
        self.assertChoices(f, expected)

    def test_allow_folders(self):
        f = FilePathField(path=self.path, allow_folders=True, allow_files=False)
        self.assertChoices(f, [
            ('/filepathfield_test_dir/c', 'c'),
            ('/filepathfield_test_dir/h', 'h'),
            ('/filepathfield_test_dir/j', 'j'),
        ])

    def test_recursive_no_folders_or_files(self):
        f = FilePathField(path=self.path, recursive=True, allow_folders=False, allow_files=False)
        self.assertChoices(f, [])

    def test_recursive_folders_without_files(self):
        f = FilePathField(path=self.path, recursive=True, allow_folders=True, allow_files=False)
        self.assertChoices(f, [
            ('/filepathfield_test_dir/c', 'c'),
            ('/filepathfield_test_dir/h', 'h'),
            ('/filepathfield_test_dir/j', 'j'),
            ('/filepathfield_test_dir/c/f', 'c/f'),
        ])