"""Convert a NT pathname to a file URL and vice versa.

This module only exists to provide OS-specific code
for urllib.requests, thus do not use directly.
"""
# Testing is done through test_urllib.

def url2pathname(url):
 """OS-specific conversion from a relative URL of the 'file' scheme
 to a file system path; not recommended for general use."""
 # e.g.
 # ///C|/foo/bar/spam.foo
 # and
 # ///C:/foo/bar/spam.foo
 # become
 # C:\foo\bar\spam.foo
 import string, urllib.parse
 # Windows itself uses ":" even in URLs.
 url = url.replace(':', '|')
 if not '|' in url:
 # No drive specifier, just convert slashes
 if url[:4] == '////':
 # path is something like ////host/path/on/remote/host
 # convert this to \\host\path\on\remote\host
 # (notice halving of slashes at the start of the path)
 url = url[2:]
 components = url.split('/')
 # make sure not to convert quoted slashes :-)
 return urllib.parse.unquote('\\'.join(components))
 comp = url.split('|')
 if len(comp) != 2 or comp[0][-1] not in string.ascii_letters:
 error = 'Bad URL: ' + url
 raise OSError(error)
 drive = comp[0][-1].upper()
 components = comp[1].split('/')
 path = drive + ':'
 for comp in components:
 if comp:
 path = path + '\\' + urllib.parse.unquote(comp)
 # Issue #11474 - handing url such as |c/|
 if path.endswith(':') and url.endswith('/'):
 path += '\\'
 return path

def pathname2url(p):
 """OS-specific conversion from a file system path to a relative URL
 of the 'file' scheme; not recommended for general use."""
 # e.g.
 # C:\foo\bar\spam.foo
 # becomes
 # ///C:/foo/bar/spam.foo
 import urllib.parse
 # First, clean up some special forms. We are going to sacrifice
 # the additional information anyway
 if p[:4] == '\\\\?\\':
 p = p[4:]
 if p[:4].upper() == 'UNC\\':
 p = '\\' + p[4:]
 elif p[1:2] != ':':
 raise OSError('Bad path: ' + p)
 if not ':' in p:
 # No drive specifier, just convert slashes and quote the name
 if p[:2] == '\\\\':
 # path is something like \\host\path\on\remote\host
 # convert this to ////host/path/on/remote/host
 # (notice doubling of slashes at the start of the path)
 p = '\\\\' + p
 components = p.split('\\')
 return urllib.parse.quote('/'.join(components))
 comp = p.split(':', maxsplit=2)
 if len(comp) != 2 or len(comp[0]) > 1:
 error = 'Bad path: ' + p
 raise OSError(error)

 drive = urllib.parse.quote(comp[0].upper())
 components = comp[1].split('\\')
 path = '///' + drive + ':'
 for comp in components:
 if comp:
 path = path + '/' + urllib.parse.quote(comp)
 return path