#!/usr/bin/env python
"""
SimpleStripper: VERY simple HTML stripper class.

Usage: SimpleStripper.strip(html)

Returns: a list of stripped paragraphs. 
"""

__version__ = '$Revision: 1.1 $'
__author__ = "Garth T Kidd <garth@deadlybloodyserious.com>"

from HTMLParser import HTMLParser

_betweenMatrix = {
    (1, 0): '',  # no space between word and punctuation
    (1, 1): ' ', # space between words
    (0, 1): '',  # no space between punctuation and word
    (0, 0): ''   # no space between punctuation
    }

def concat(left, right):
    "Quasi-intelligent string concatenation."
    tail = left[-1:]
    head = right[0:1]
    between = _betweenMatrix[(head.isalpha(), tail.isalpha())]
    result = left + between + right
    if head.isalpha() and tail in ['.', ',', ')', ']', '}']:
        result = left + ' ' + right
    return result

def truncate(str, length):
    "Truncate a string at a particular length."
    if len(str)<=length:
        return str
    else:
        return str[0:length-3] + '...'

class StrippingParser(HTMLParser):
    def __init__(self):
        self.paras = []
        self.inp = 0
        self.para = ''
        HTMLParser.__init__(self)

    def handle_data(self, data):
        data = data.strip()
        if data:
            if self.para:
                self.para = concat(self.para, data)
            else:
                self.para = data

    def handle_starttag(self, tag, atts):
        if tag in ['p', 'P']:
            if self.inp: # started another
                self.endPara()
            self.inp = 1

    def handle_endtag(self, tag):
        if tag in ['p', 'P']: 
            self.endPara()

    def endPara(self):
        if self.inp: 
            self.paras.append(self.para)
        self.para = ''
        self.inp = 0            

    def close(self):
        if self.para:
            self.inp = 1 # just in case
            self.endPara()
        HTMLParser.close(self)

def strip(html):
    sp = StrippingParser()
    sp.feed(html)
    sp.close()
    return sp.paras

if __name__ == '__main__':
    from pprint import pprint
    tests = [
        'This is a test.',
        '<p>This is a test.</p>',
        '<p>This<br> is a test.</p>',
        '<p>This is a <strong>test</strong>'
        ]

    line = '-' * 79
    num = 0
    for test in tests:
        num += 1
        print line
        print "Test #%d\n%s => " % (num, repr(test)), 
        pprint(strip(test))