'''
    markup / media -- conversion / coercion
'''
from peak.rules import abstract, when

class htmlstr(str):
    pass

class uhtmlstr(unicode):
    pass

@abstract()
def plain_text(s):
    ''' Returns the text passed as a markup free / plain text string. '''

@abstract()
def html_text(s):
    ''' Returns the text passed as an html marked-up text string. '''

@when(html_text, (str, unicode))
def txt2html(s):
    return  ''.join(['<p>', s, '</p>' ])

@when(html_text, (htmlstr, uhtmlstr))
def html2html(s):
    return s

def txt2txt(s):
    return s
when(plain_text, (str,))(txt2txt)
when(plain_text, (unicode,))(txt2txt)

@when(plain_text, (htmlstr, uhtmlstr))
def html2txt(s):
    return re.sub(r'<[^>]*?>','',s)