import json
import random

from flasgger import Swagger
from flasgger.utils import get_examples


def get_specs_data(mod):
    """
    return all specs dictionary for some app
    """
    # for each example app in /examples folder
    client = mod.app.test_client()
    # init swag if not yet inititalized (no-routes example)
    specs_route = None
    specs_data = {}
    if getattr(mod.app, 'swag', None) is None:
        _swag = Swagger()
        _swag.config['endpoint'] = str(random.randint(1, 5000))
        _swag.init_app(mod.app)
    # get all the specs defined for the example app
    else:
        try:
            flasgger_config = mod.swag.config

            if flasgger_config.get('swagger_ui') is False:
                return specs_data

            specs_route = flasgger_config.get('specs_route', '/apidocs/')
        except AttributeError:
            pass

    if specs_route is None:
        specs_route = '/apidocs/'

    apidocs = client.get('?'.join((specs_route, 'json=true')))
    specs = json.loads(apidocs.data.decode("utf-8")).get('specs')

    for spec in specs:
        # for each spec get the spec url
        url = spec['url']
        response = client.get(url)
        decoded = response.data.decode("utf-8")
        specs_data[url] = json.loads(decoded)

    return specs_data


def get_test_metadata(mod):
    """Create a dictionary of test metadata defined in an example

    Every top-level constant prefixed with "_TEST_META_" is treated as
    metadata which may control test behavior. The prefix is stripped and the
    remaining text is lowercased to form the key in the metadata dictionary.

    Example: '_TEST_META_SKIP_FULL_VALIDATION' -> 'skip_full_validation'
    """

    test_metadata_prefix = '_TEST_META_'
    return {key[len(test_metadata_prefix):].lower(): getattr(mod, key)
            for key in mod.__dict__
            if key.startswith(test_metadata_prefix)}


def pytest_generate_tests(metafunc):
    """
    parametrize tests using examples() function
    to generate one test for each examples/
    """

    if 'test_data' in metafunc.fixturenames:
        test_data = [
            (mod, mod.app.test_client(),
             get_specs_data(mod), get_test_metadata(mod))
            for mod in get_examples()
        ]

        metafunc.parametrize(
            'test_data',
            test_data,
            ids=lambda x: x[0].__name__
        )