import io
import json
import os

import html5lib
import pytest
from selenium import webdriver

from wptserver import WPTServer

ENC = 'utf8'
HERE = os.path.dirname(os.path.abspath(__file__))
WPT_ROOT = os.path.normpath(os.path.join(HERE, '..', '..'))
HARNESS = os.path.join(HERE, 'harness.html')
TEST_TYPES = ('functional', 'unit')

def pytest_addoption(parser):
    parser.addoption("--binary", action="store", default=None, help="path to browser binary")

def pytest_collect_file(path, parent):
    if path.ext.lower() != '.html':
        return

    # Tests are organized in directories by type
    test_type = os.path.relpath(str(path), HERE).split(os.path.sep)[1]

    return HTMLItem(str(path), test_type, parent)

def pytest_configure(config):
    config.driver = webdriver.Firefox(firefox_binary=config.getoption("--binary"))
    config.server = WPTServer(WPT_ROOT)
    config.server.start()
    config.add_cleanup(config.server.stop)
    config.add_cleanup(config.driver.quit)

def resolve_uri(context, uri):
    if uri.startswith('/'):
        base = WPT_ROOT
        path = uri[1:]
    else:
        base = os.path.dirname(context)
        path = uri

    return os.path.exists(os.path.join(base, path))

class HTMLItem(pytest.Item, pytest.Collector):
    def __init__(self, filename, test_type, parent):
        self.filename = filename
        self.type = test_type
        self.variants = []

        if test_type not in TEST_TYPES:
            raise ValueError('Unrecognized test type: "%s"' % test_type)

        with io.open(filename, encoding=ENC) as f:
            markup = f.read()

        parsed = html5lib.parse(markup, namespaceHTMLElements=False)
        name = None
        includes_variants_script = False
        self.expected = None

        for element in parsed.getiterator():
            if not name and element.tag == 'title':
                name = element.text
                continue
            if element.tag == 'meta' and element.attrib.get('name') == 'variant':
                self.variants.append(element.attrib.get('content'))
                continue
            if element.tag == 'script':
                if element.attrib.get('id') == 'expected':
                    self.expected = json.loads(unicode(element.text))

                src = element.attrib.get('src', '')

                if 'variants.js' in src:
                    includes_variants_script = True
                    if not resolve_uri(filename, src):
                        raise ValueError('Could not resolve path "%s" from %s' % (src, filename))

        if not name:
            raise ValueError('No name found in file: %s' % filename)
        elif self.type == 'functional':
            if not self.expected:
                raise ValueError('Functional tests must specify expected report data')
            if not includes_variants_script:
                raise ValueError('No variants script found in file: %s' % filename)
            if len(self.variants) == 0:
                raise ValueError('No test variants specified in file %s' % filename)
        elif self.type == 'unit' and self.expected:
            raise ValueError('Unit tests must not specify expected report data')

        super(HTMLItem, self).__init__(name, parent)


    def reportinfo(self):
        return self.fspath, None, self.filename

    def repr_failure(self, excinfo):
        return pytest.Collector.repr_failure(self, excinfo)

    def runtest(self):
        if self.type == 'unit':
            self._run_unit_test()
        elif self.type == 'functional':
            self._run_functional_test()
        else:
            raise NotImplementedError

    def _run_unit_test(self):
        driver = self.session.config.driver
        server = self.session.config.server

        driver.get(server.url(HARNESS))

        actual = driver.execute_async_script('runTest("%s", "foo", arguments[0])' % server.url(str(self.filename)))

        summarized = self._summarize(actual)

        assert summarized[u'summarized_status'][u'status_string'] == u'OK', summarized[u'summarized_status'][u'message']
        for test in summarized[u'summarized_tests']:
            msg = "%s\n%s" % (test[u'name'], test[u'message'])
            assert test[u'status_string'] == u'PASS', msg

    def _run_functional_test(self):
        for variant in self.variants:
            self._run_functional_test_variant(variant)

    def _run_functional_test_variant(self, variant):
        driver = self.session.config.driver
        server = self.session.config.server

        driver.get(server.url(HARNESS))

        test_url = server.url(str(self.filename) + variant)
        actual = driver.execute_async_script('runTest("%s", "foo", arguments[0])' % test_url)

        # Test object ordering is not guaranteed. This weak assertion verifies
        # that the indices are unique and sequential
        indices = [test_obj.get('index') for test_obj in actual['tests']]
        self._assert_sequence(indices)

        summarized = self._summarize(actual)

        assert summarized == self.expected

    def _summarize(self, actual):
        summarized = {}

        summarized[u'summarized_status'] = self._summarize_status(actual['status'])
        summarized[u'summarized_tests'] = [
            self._summarize_test(test) for test in actual['tests']]
        summarized[u'summarized_tests'].sort(key=lambda test_obj: test_obj.get('name'))
        summarized[u'type'] = actual['type']

        return summarized

    @staticmethod
    def _assert_sequence(nums):
        if nums and len(nums) > 0:
            assert nums == range(1, nums[-1] + 1)

    @staticmethod
    def _scrub_stack(test_obj):
        copy = dict(test_obj)
        del copy['stack']
        return copy

    @staticmethod
    def _expand_status(status_obj):
        for key, value in [item for item in status_obj.items()]:
            # In "status" and "test" objects, the "status" value enum
            # definitions are interspersed with properties for unrelated
            # metadata. The following condition is a best-effort attempt to
            # ignore non-enum properties.
            if key != key.upper() or not isinstance(value, int):
                continue

            del status_obj[key]

            if status_obj['status'] == value:
                status_obj[u'status_string'] = key

        del status_obj['status']

        return status_obj

    @staticmethod
    def _summarize_test(test_obj):
        del test_obj['index']

        assert 'phase' in test_obj
        assert 'phases' in test_obj
        assert 'COMPLETE' in test_obj['phases']
        assert test_obj['phase'] == test_obj['phases']['COMPLETE']
        del test_obj['phases']
        del test_obj['phase']

        return HTMLItem._expand_status(HTMLItem._scrub_stack(test_obj))

    @staticmethod
    def _summarize_status(status_obj):
        return HTMLItem._expand_status(HTMLItem._scrub_stack(status_obj))