#pylint: disable=too-many-public-methods
from functools import reduce
import os, re, shutil, tempfile
import unittest
from gleetex import htmlhandling


excl_filename = htmlhandling.HtmlImageFormatter.EXCLUSION_FILE_NAME

HTML_SKELETON = '''<html><head><meta http-equiv="Content-Type" content="text/html; charset={0}" />
</head><body>{1}</body>'''

def read(file_name, mode='r', encoding='utf-8'):
   """Read the file, return the string. Close file properly."""
   with open(file_name, mode, encoding=encoding) as handle:
       return handle.read()


class HtmlparserTest(unittest.TestCase):
   def setUp(self):
       self.p = htmlhandling.EqnParser()

   def test_start_tags_are_parsed_literally(self):
       self.p.feed("<p   i='o'>")
       self.assertEqual(self.p.get_data()[0], "<p   i='o'>",
               "The HTML parser should copy start tags literally.")

   def test_that_end_tags_are_copied_literally(self):
       self.p.feed("</ p></P>")
       self.assertEqual(''.join(self.p.get_data()), "</ p></P>")

   def test_entities_are_unchanged(self):
       self.p.feed("&#xa;")
       self.assertEqual(self.p.get_data()[0], '&#xa;')

   def test_charsets_are_copied(self):
       self.p.feed('&gt;&rarr;')
       self.assertEqual(''.join(self.p.get_data()[0]), '&gt;&rarr;')

   def test_without_eqn_all_blocks_are_strings(self):
       self.p.feed("<html>\n<head/><body><p>42</p><h1>blah</h1></body></html>")
       self.assertTrue(reduce(lambda x,y: x and isinstance(y, str),
           self.p.get_data()), "all chunks have to be strings")

   def test_equation_is_detected(self):
       self.p.feed('<eq>foo \\pi</eq>')
       self.assertTrue(isinstance(self.p.get_data()[0], (tuple, list)))
       self.assertEqual(self.p.get_data()[0][2], 'foo \\pi')

   def test_tag_followed_by_eqn_is_correctly_recognized(self):
       self.p.feed('<p foo="bar"><eq>bar</eq>')
       self.assertEqual(self.p.get_data()[0], '<p foo="bar">')
       self.assertTrue(isinstance(self.p.get_data(), list), "second item of data must be equation data list")

   def test_document_with_tag_then_eqn_then_tag_works(self):
       self.p.feed('<div style="invalid">bar</div><eq>baz</eq><sometag>')
       eqn = None
       # test should not depend on a specific position of equation, search for
       # it
       data = self.p.get_data()
       for chunk in data:
           if isinstance(chunk, (tuple, list)):
               eqn = chunk
               break
       self.assertTrue(isinstance(data[0], str))
       self.assertTrue(eqn is not None,
               "No equation found, must be tuple/list object.")
       self.assertTrue(isinstance(data[-1], str))

   def test_equation_is_copied_literally(self):
       self.p.feed('<eq ignore="me">my\nlittle\n\\tau</eq>')
       self.assertEqual(self.p.get_data()[0][2], 'my\nlittle\n\\tau')

   def test_unclosed_eqns_are_detected(self):
       self.assertRaises(htmlhandling.ParseException, self.p.feed,
               '<p><eq>\\endless\\formula')

   def test_nested_formulas_trigger_exception(self):
       self.assertRaises(htmlhandling.ParseException, self.p.feed,
               "<eq>\\pi<eq></eq></eq>")
       self.assertRaises(htmlhandling.ParseException, self.p.feed,
               "<eq>\\pi<eq></p></eq>")

   def test_formulas_without_displaymath_attribute_are_detected(self):
       self.p.feed('<p><eq>\frac12</eq><br /><eq env="inline">bar</eq></p>')
       formulas = [c for c in self.p.get_data() if isinstance(c, (tuple, list))]
       self.assertEqual(len(formulas), 2) # there should be _2_ formulas
       self.assertEqual(formulas[0][1], False) # no displaymath
       self.assertEqual(formulas[1][1], False) # no displaymath

   def test_that_unclosed_formulas_detected(self):
           self.assertRaises(htmlhandling.ParseException, self.p.feed,
               "<eq>\\pi<eq></p>")
           self.assertRaises(htmlhandling.ParseException, self.p.feed,
               "<eq>\\pi")


   def test_formula_contains_only_formula(self):
       p = htmlhandling.EqnParser()
       p.feed("<p><eq>1<i<9</eq></p>")
       formula = next(e for e in p.get_data() if isinstance(e, (list, tuple)))
       self.assertEqual(formula[-1], "1<i<9")

       p = htmlhandling.EqnParser()
       p.feed('<p><eq env="displaymath">test</eq></p>')
       formula = next(e for e in p.get_data() if isinstance(e, (list, tuple)))
       self.assertEqual(formula[-1], "test")

       p = htmlhandling.EqnParser()
       p.feed("<p><eq>1<i<9</eq></p>")
       formula = next(e for e in p.get_data() if isinstance(e, (list, tuple)))
       self.assertEqual(formula[-1], "1<i<9")


   def test_formula_with_html_sequences_are_unescaped(self):
       self.p.feed('<eq>a&gt;b</eq>')
       formula = self.p.get_data()[0]
       self.assertEqual(formula[-1], "a>b")


   def test_displaymath_is_recognized(self):
       self.p.feed('<eq env="displaymath">\\sum\limits_{n=1}^{e^i} a^nl^n</eq>')
       self.assertEqual(self.p.get_data()[0][1], True) # displaymath flag set

   def test_encoding_is_parsed_from_HTML4(self):
       iso8859_1 = HTML_SKELETON.format('iso-8859-15', 'öäüß').encode('iso-8859-1')
       self.p.feed(iso8859_1)
       self.assertEqual(self.p._EqnParser__encoding, 'iso-8859-15')

   def test_encoding_is_parsed_from_HTML5(self):
       document = r"""<!DOCTYPE html>
           <html xmlns="http://www.w3.org/1999/xhtml" lang="" xml:lang="">
           <head><meta charset="utf-8" />
             <meta name="generator" content="pandoc" />
             </head><body><p>hi</p></body></html>"""
       self.p.feed(document.encode('utf-8'))
       self.assertEqual(self.p._EqnParser__encoding.lower(), 'utf-8')


   def test_strings_can_be_passed_tO_parser_as_well(self):
       # no exception - everything is working as expected
       self.p.feed(HTML_SKELETON.format('utf-8', 'æø'))

class GetPositionTest(unittest.TestCase):
   def test_that_line_number_is_correct(self):
       self.assertEqual(htmlhandling.get_position('jojo', 0)[0], 0)
       self.assertEqual(htmlhandling.get_position('jojo', 3)[0], 0)
       self.assertEqual(htmlhandling.get_position('a\njojo', 3)[0], 1)
       self.assertEqual(htmlhandling.get_position('a\n\njojo', 3)[0], 2)

   def test_that_position_on_line_is_correct(self):
       self.assertEqual(htmlhandling.get_position('jojo', 0)[1], 0)
       self.assertEqual(htmlhandling.get_position('jojo', 3)[1], 3)
       self.assertEqual(htmlhandling.get_position('a\njojo', 3)[1], 2)
       self.assertEqual(htmlhandling.get_position('a\n\njojo', 3)[1], 1)




class HtmlImageTest(unittest.TestCase):
   def setUp(self):
       self.pos = {'depth':99, 'height' : 88, 'width' : 77}
       self.original_directory = os.getcwd()
       self.tmpdir = tempfile.mkdtemp()
       os.chdir(self.tmpdir)

   def tearDown(self):
       os.chdir(self.original_directory)
       shutil.rmtree(self.tmpdir, ignore_errors=True)

   def test_that_no_file_is_written_if_no_content(self):
       with htmlhandling.HtmlImageFormatter('foo.html'):
           pass
       self.assertFalse(os.path.exists('foo.html')        )

   def test_file_if_written_when_content_exists(self):
       with htmlhandling.HtmlImageFormatter() as img:
           img.format_excluded(self.pos, '\\tau\\tau', 'foo.png')
       self.assertTrue(os.path.exists(excl_filename)        )

   def test_written_file_starts_and_ends_more_or_less_properly(self):
       with htmlhandling.HtmlImageFormatter('.') as img:
           img.format_excluded(self.pos, '\\tau\\tau', 'foo.png')
       data = read(htmlhandling.HtmlImageFormatter.EXCLUSION_FILE_NAME, 'r', encoding='utf-8')
       self.assertTrue('<html' in data and '</html>' in data)
       self.assertTrue('<body' in data and '</body>' in data)
       # make sure encoding is specified
       self.assertTrue('<meta' in data and 'charset=' in data)

   def test_id_contains_no_special_characters(self):
       data = htmlhandling.gen_id('\\tau!\'{}][~^')
       for character in {'!', "'", '\\', '{', '}'}:
           self.assertFalse(character in data)

   def test_formula_can_consist_only_of_numbers_and_id_is_generated(self):
       data = htmlhandling.gen_id('9*8*7=504')
       self.assertTrue(data.startswith('form'))
       self.assertTrue(data.endswith('504'))

   def test_that_empty_ids_raise_exception(self):
       self.assertRaises(ValueError, htmlhandling.gen_id, '')

   def test_that_same_characters_are_not_repeated(self):
       id = htmlhandling.gen_id("jo{{{{{{{{ha")
       self.assertEqual(id, "jo_ha")

   def test_that_ids_are_max_150_characters_wide(self):
       id = htmlhandling.gen_id('\\alpha\\cdot\\gamma + ' * 999)
       self.assertTrue(len(id) == 150)

   def test_that_ids_start_with_letter(self):
       id = htmlhandling.gen_id('{}\\[]ÖÖÖö9343...·tau')
       self.assertTrue(id[0].isalpha())

   def test_that_link_to_external_image_points_to_file_and_formula(self):
       with htmlhandling.HtmlImageFormatter() as img:
           formatted_img = img.format_excluded(self.pos, '\\tau\\tau', 'foo.png')
           expected_id = htmlhandling.gen_id('\\tau\\tau')
       external_file = read(excl_filename, 'r', encoding='utf-8')
       # find linked formula path
       href = re.search('href="(.*?)"', formatted_img)
       self.assertTrue(href != None)
       # extract path and id from it
       self.assertTrue('#' in href.groups()[0])
       path, id = href.groups()[0].split('#')
       self.assertEqual(path, excl_filename)
       self.assertEqual(id, expected_id)

       # check external file
       self.assertTrue('<p id' in external_file)
       self.assertTrue('="'+expected_id in external_file)


   def test_that_link_to_external_image_points_to_file_basepath_and_formula(self):
       os.mkdir('basepath')
       with htmlhandling.HtmlImageFormatter('basepath') as img:
           formatted_img = img.format_excluded(self.pos, '\\tau\\tau', 'foo.png')
           expected_id = htmlhandling.gen_id('\\tau\\tau')
       # find linked formula path
       href = re.search('href="(.*?)"', formatted_img)
       self.assertTrue(href != None)
       # extract path and id from it
       self.assertTrue('#' in href.groups()[0])
       path, id = href.groups()[0].split('#')
       self.assertEqual(path, 'basepath/' + excl_filename)
       self.assertEqual(id, expected_id)

   def test_height_and_width_is_in_formatted_html_img_tag(self):
       data = None
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           data = img.get_html_img(self.pos, '\\tau\\tau', 'foo.png')
       self.assertTrue('height=' in data and str(self.pos['height']) in data)
       self.assertTrue('width=' in data and str(self.pos['width']) in data)

   def test_no_formula_gets_lost_when_reparsing_external_formula_file(self):
       with htmlhandling.HtmlImageFormatter() as img:
           img.format_excluded(self.pos, '\\tau' * 999, 'foo.png')
       with htmlhandling.HtmlImageFormatter() as img:
           img.format_excluded(self.pos, '\\pi' * 666, 'foo_2.png')
       data = read(excl_filename)
       self.assertTrue('\\tau' in data)
       self.assertTrue('\\pi' in data)

   def test_too_long_formulas_are_not_outsourced_if_not_configured(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.format(self.pos, '\\tau' * 999, 'foo.png')
       self.assertFalse(os.path.exists('foo.html'))

   def test_that_too_long_formulas_get_outsourced_if_configured(self):
       with htmlhandling.HtmlImageFormatter() as img:
           img.set_max_formula_length(90)
           img.set_exclude_long_formulas(True)
           img.format(self.pos, '\\tau' * 999, 'foo.png')
       self.assertTrue(os.path.exists(excl_filename))
       data = read(htmlhandling.HtmlImageFormatter.EXCLUSION_FILE_NAME)
       self.assertTrue('\\tau\\tau' in data)

   def test_url_is_included(self):
       prefix = "http://crustulus.de/blog"
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.set_url(prefix)
           data = img.format(self.pos, '\epsilon<0', 'foo.png')
           self.assertTrue( prefix in data)

   def test_url_doesnt_contain_double_slashes(self):
       prefix = "http://crustulus.de/blog/"
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.set_url(prefix)
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png')
           self.assertFalse('//' in data.replace('http://','ignore'))

   # depth is used as negative offset, so negative depth should result in
   # positive offset
   def test_that_negative_depth_results_in_positive_offset(self):
       self.pos['depth'] = '-999'
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png')
           self.assertTrue('align: ' + str(self.pos['depth'])[1:] in data)

   def test_that_displaymath_is_set_or_unset(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png',
                   True)
           self.assertTrue('="displaymath' in data)
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png',
                   False)
           self.assertTrue('="inlinemath' in data)

   def test_that_alternative_css_class_is_set_correctly(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.set_display_math_css_class('no1')
           img.set_inline_math_css_class('no2')
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png',
                   True)
           self.assertTrue('="no1"' in data)
           data = img.format(self.pos, r'\gamma\text{strahlung}', 'foo.png',
                   False)
           self.assertTrue('="no2' in data)

   def test_that_unicode_is_replaced_if_requested(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.set_replace_nonascii(True)
           data = img.format(self.pos, '←', 'foo.png')
           self.assertTrue('\\leftarrow' in data,
                   'expected: "\\leftarrow" to be in "%s"' % data)

   def test_that_unicode_is_kept_if_not_requested_to_replace(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           img.set_replace_nonascii(False)
           data = img.format(self.pos, '←', 'foo.png')
           self.assertTrue('←' in data)

   def test_formatting_commands_are_stripped(self):
       with htmlhandling.HtmlImageFormatter('foo.html') as img:
           data = img.format(self.pos, 'a\,b\,c\,d', 'foo.png')
           self.assertTrue('a b c d' in data)
           data = img.format(self.pos, 'a\,b\;c\ d', 'foo.png')
           self.assertTrue('a b c d' in data)

           data = img.format(self.pos, '\Big\{foo\Big\}', 'foo.png')
           self.assertTrue('\{foo' in data and '\}' in data)
           data = img.format(self.pos, r'\left\{foo\right\}', 'foo.png')
           self.assertTrue('\{' in data and 'foo' in data and '\}' in data)


def htmleqn(formula, hr=True):
   """Format a formula to appear as if it would have been outsourced into an
   external file."""
   return '%s\n<p id="%s"><pre>%s</pre></span></p>\n' % (\
           ('<hr/>' if hr else ''), htmlhandling.gen_id(formula), formula)


class OutsourcingParserTest(unittest.TestCase):
   def setUp(self):
       self.html = ('<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"' +
       '\n  "http://www.w3.org/TR/html4/strict.dtd">\n<html>\n<head>\n' +
       '<meta http-equiv="content-type" content="text/html; charset=utf-8"/>' +
       '<title>Outsourced Formulas</title></head>\n<body>\n<h1>heading</h1>')

   def get_html(self, string):
       """Create html string with head / tail und put the specified string into
       it."""
       return self.html + string + '\n</body>\n</html>'


   def test_formulas_are_recognized(self):
       data = self.get_html(htmleqn('\\tau'))
       parser = htmlhandling.OutsourcedFormulaParser()
       parser.feed(data)
       self.assertEqual(len(parser.get_formulas()), 1)

   def test_formula_doesnt_contain_surrounding_rubbish(self):
       data = self.get_html(htmleqn('\\gamma'))
       parser = htmlhandling.OutsourcedFormulaParser()
       parser.feed(data)
       self.assertEqual(len(parser.get_formulas()), 1)
       key = next(iter(parser.get_formulas()))
       par = parser.get_formulas()[key]
       self.assertFalse('<h1' in par)
       self.assertFalse('body>' in par)
       self.assertFalse('hr' in par)

   def test_that_header_is_parsed_correctly(self):
       p = htmlhandling.OutsourcedFormulaParser()
       p.feed(self.get_html(htmleqn('test123', False)))
       head = p.get_head()
       self.assertTrue('DOCTYPE' in head)
       self.assertTrue('<html' in head)
       self.assertTrue('<title' in head)
       self.assertTrue('</title' in head)
       self.assertTrue('</head' in head)
       self.assertTrue('<meta' in head)
       self.assertTrue('charset=' in head)

   def test_multiple_formulas_are_recognized_correctly(self):
       p = htmlhandling.OutsourcedFormulaParser()
       p.feed(self.get_html(htmleqn('\\tau', False) + '\n' +
           htmleqn('\\gamma') + '\n' + htmleqn('\\epsilon<0')))
       forms = p.get_formulas()
       self.assertEqual(len(forms), 3)
       self.assertTrue('\\gamma' in forms.values())
       self.assertTrue('\\gamma' in forms.values())
       self.assertTrue('\\epsilon<0' in forms.values())