#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
import urllib

from lxml import etree

def print_value(_, node, v):
    '''A dummy function - just to test the variable'''
    if isinstance(v, list):
        return v[0]
    else:
        return v

def quote(_, s):
    '''Encodes the input text to be used in URLs'''
    if isinstance(s, unicode):
        return urllib.quote(s.encode('utf-8'))
    elif isinstance(s, etree._Element):
        return urllib.quote(s.text)
    elif isinstance(s, str):
        return urllib.quote(s)
    elif isinstance(s, list):
        return quote(_, s[0])
    else:
        return urllib.quote(str(int(s)))

def main():
    '''Test xsl:variable in external functions'''
    ns = etree.FunctionNamespace('http://rambler.ru/fe')
    ns.prefix = "fe"
    ns['print_value'] = print_value
    ns['quote'] = quote

    style = etree.XML('''
    <xsl:stylesheet version="1.0"
        xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
        xmlns:fe="http://rambler.ru/fe"
        extension-element-prefixes="fe">

        <xsl:variable name="maxlen">42</xsl:variable>
        <xsl:variable name="trick">trick</xsl:variable>
        <xsl:variable name="tree">
            <baum>a=test</baum>
        </xsl:variable>

        <xsl:template match="content">
        <result>
          <test1>
             Not using a variable: <xsl:value-of select="fe:print_value(text(),20)"/>
             With a variable: <xsl:value-of select="fe:print_value(text(),$maxlen)"/>
          </test1>
          <test2>
             Not using a variable: <xsl:value-of select="fe:quote('aaa')"/>
             With a variable: <xsl:value-of select="fe:quote($trick)"/>
          </test2>
          <test3>
             Not using a variable: <xsl:value-of select="fe:quote(20)"/>
             With a variable: <xsl:value-of select="fe:quote($tree)"/>
          </test3>
        </result>
        </xsl:template>

    </xsl:stylesheet>''')
    transform = etree.XSLT(style)

    data = etree.XML('''
    <test>
                <content>A very long text a very long text a very long text a very long text a very long text a very long text a very long text a very long text a very long text</content>
    </test>
    ''')

    result_tree = transform(data)
    print etree.tounicode(result_tree,  pretty_print=True)

    print "lxml.etree:       ", etree.LXML_VERSION
    print "libxml used:      ", etree.LIBXML_VERSION
    print "libxml compiled:  ", etree.LIBXML_COMPILED_VERSION
    print "libxslt used:     ", etree.LIBXSLT_VERSION
    print "libxslt compiled: ", etree.LIBXSLT_COMPILED_VERSION
    return 0

if __name__ == '__main__':
    sys.exit(main())