#/usr/bin/python
'''Methods for parsing a Java properties file as described by:
    http://java.sun.com/j2se/1.4.2/docs/api/java/util/Properties.html
'''
import sys
backslash = '\\'
def parsePropertyLine(s):
    '''Returns the property string and a boolean indicating whether the property ends with a line-continuation character.
    If the line does end in a conitinueing \, then that character is NOT returned in the string.'''
    if not s.endswith(backslash):
        return s, False
    ls = len(s)
    last = ls - 1
    for i in  range(1, last):
        if s[last - i] != backslash:
            if i%2:
                return s[:-1], True
            return s, False
            
    if last % 2:
        return s[:-1], True
    return s, False

_escapeToWriteDict = {
        '\n' : '\\n',
        '\r' : '\\r',
        '\t' : '\\t',
        ' ' : '\\ ',
        backslash : backslash + backslash
        
        }
_readingEscapeDict = {
        'n' : '\n',
        't' : '\t',
        'r' : '\r',
        }

def parsePropString(s):
    keyList = []
    valList = []
    escape = False
    separatorSeen = False
    charIterator = iter(s)
    for c in charIterator:
        if escape:
            keyList.append(_readingEscapeDict.get(c,c))
            escape = False
        elif c == backslash:
            escape = True
        else:
            if c in [':', '=']:
                separatorSeen = True
                break
            elif c.isspace():
                break
            keyList.append(c)
    for c in charIterator:
        if (not separatorSeen) and (c in [':', '=']):
            separatorSeen = True
        else:   
            if not c.isspace():
                valList.append(c)
                break
    for c in charIterator:
        if escape:
            valList.append(_readingEscapeDict.get(c,c))
            escape = False
        elif c == backslash:
            escape = True
        else:
            valList.append(c)
    value = ''.join(valList)
    return ''.join(keyList), value
    
def propertyIterator(fileObj):
    currComments = []
    propStr = ''
    for linePlus in fileObj:
        line = linePlus[:-1]
        lstrLine = line.lstrip()
        if lstrLine:
            if lstrLine[0] == '#' or lstrLine[0] == ':':
                if propStr:
                    key, val = parsePropString(propStr)
                    yield key, val, '\n'.join(currComments)
                    currComments = [line]
                    propStr = ''
                else:
                    currComments.append(line)
            else:
                p, midLine = parsePropertyLine(lstrLine)
                propStr = propStr + p
                if not midLine:
                    key, val = parsePropString(propStr)
                    yield key, val, '\n'.join(currComments)
                    currComments = []
                    propStr = ''
        else:
            currComments.append('')
    if propStr or currComments:
        if propStr:
            key, val = parsePropString(propStr)
        else:
            key, val = '', ''
        yield key, val, '\n'.join(currComments)

def escape(s):
    return ''.join([_escapeToWriteDict.get(i, i) for i in s])
if __name__ == '__main__':
    ind = 1
    outputComments = False
    if  len(sys.argv) > 1 and sys.argv[1] == '-c':
        outputComments = True
        ind = 2
    files = sys.argv[ind:]
    if not files:
        files = [None]
    for file in files:
        try:
            if file is not None:
                f = open(file, 'rU')
            else:
                f = sys.stdin
        except IOError:
            sys.exit('Could not open %s' % f)
        for k, v, c in propertyIterator(f):
            if outputComments:
                if k:
                    if c:
                        sys.stdout.write('%s\n%s=%s\n' % (c, escape(k), escape(v)))
                    else:
                        sys.stdout.write('%s=%s\n' % (escape(k), escape(v)))
                else:
                    sys.stdout.write('%s\n' % c)
            elif k:
                sys.stdout.write('%s=%s\n' % (escape(k), escape(v)))