#!/bin/env python

'''
unit testing of NeXus definitions NXDL files and XML Schema
'''

import os
import sys
import unittest
import lxml.etree
from six import with_metaclass

# xmllint --noout --schema nxdl.xsd base_classes/NXentry.nxdl.xml 
# base_classes/NXentry.nxdl.xml validates


BASE_DIR = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
NXDL_XSD_SCHEMA = 'nxdl.xsd'
NXDL_SCHEMA = lxml.etree.XMLSchema(
    lxml.etree.parse(
        os.path.join(BASE_DIR, NXDL_XSD_SCHEMA)))

NXDL_CATEGORY_NAMES = 'base_classes applications contributed_definitions'.split()


class NXDL_Invalid(Exception): pass
class NXDL_Valid(Exception): pass


def isNXDL(fname):
    return fname.endswith('.nxdl.xml')


def get_NXDL_file_list():
    os.chdir(BASE_DIR)
    file_list = []
    for category in NXDL_CATEGORY_NAMES:
        raw_list = os.listdir(category)
        nxdl_files = [os.path.join(category, fn) for fn in raw_list if isNXDL(fn)]
        file_list += sorted(nxdl_files)
    return file_list


def validate_xml(xml_file_name):
    '''
    validate an NXDL XML file against an XML Schema file

    :param str xml_file_name: name of XML file
    '''
    try:
        xml_tree = lxml.etree.parse(xml_file_name)
    except lxml.etree.XMLSyntaxError as exc:
        msg = xml_file_name + ' : ' + str(exc)
        raise NXDL_Invalid(msg)
    try:
        result = NXDL_SCHEMA.assertValid(xml_tree)
        # there is no assertNotRaises so raise this when successful
        raise NXDL_Valid
    except lxml.etree.DocumentInvalid as exc:
        msg = xml_file_name + ' : ' + str(exc)
        raise NXDL_Invalid(msg)


class TestMaker(type):
    
    def __new__(cls, clsname, bases, dct):
        # Add a method to the class' __dict__ for every 
        # file name in the NXDL file list.
        cat_number_dict = {c: str(i+1) for i, c in enumerate(NXDL_CATEGORY_NAMES)}
        for fname in get_NXDL_file_list():
            category, nxdl_name = os.path.split(fname)
            category_number = cat_number_dict[category]
            point = nxdl_name.find(".")
            nxdl_name = nxdl_name[:point]
            test_name = 'test'
            # since these will be sorted, get the categories in the desired order
            test_name += '__' + str(category_number)
            test_name += '__' + category
            test_name += '__' + nxdl_name
            dct[test_name] = cls.make_test(fname)

        return super(TestMaker, cls).__new__(cls, clsname, bases, dct)

    @staticmethod
    def make_test(nxdl_file_name):
        
        def test_wrap(self):
            # test body for each NXDL file test
            with self.assertRaises(NXDL_Valid):
                validate_xml(nxdl_file_name)
            self.assertRaises(NXDL_Valid, validate_xml, nxdl_file_name)
        return test_wrap


class Individual_NXDL_Tests(with_metaclass(TestMaker, unittest.TestCase)):
    '''
    run all tests created in TestMaker() class, called by suite()
    '''


def suite(*args, **kw):
    '''gather all the tests together in a suite, called by run()'''
    test_suite = unittest.TestSuite()
    test_suite.addTests(unittest.makeSuite(Individual_NXDL_Tests))
    return test_suite


def run():
    '''run all the unit tests'''
    runner=unittest.TextTestRunner(verbosity=2)
    runner.run(suite())


if __name__ == '__main__':
    run()