#!/usr/bin/env python
# -*- coding: ascii -*-
#
# Copyright 2011, 2012
# Andr\xe9 Malo or his licensors, as applicable
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
r"""
=====================
 Javascript Minifier
=====================

rJSmin is a javascript minifier written in python.

The minifier is based on the semantics of `jsmin.c by Douglas Crockford`_\.

The module is a re-implementation aiming for speed, so it can be used at
runtime (rather than during a preprocessing step). Usually it produces the
same results as the original ``jsmin.c``. It differs in the following ways:

- there is no error detection: unterminated string, regex and comment
  literals are treated as regular javascript code and minified as such.
- Control characters inside string and regex literals are left untouched; they
  are not converted to spaces (nor to \n)
- Newline characters are not allowed inside string and regex literals, except
  for line continuations in string literals (ECMA-5).
- "return /regex/" is recognized correctly.
- "+ +" and "- -" sequences are not collapsed to '++' or '--'
- Newlines before ! operators are removed more sensibly
- rJSmin does not handle streams, but only complete strings. (However, the
  module provides a "streamy" interface).

Since most parts of the logic are handled by the regex engine it's way
faster than the original python port of ``jsmin.c`` by Baruch Even. The speed
factor varies between about 6 and 55 depending on input and python version
(it gets faster the more compressed the input already is). Compared to the
speed-refactored python port by Dave St.Germain the performance gain is less
dramatic but still between 1.2 and 7. See the docs/BENCHMARKS file for
details.

rjsmin.c is a reimplementation of rjsmin.py in C and speeds it up even more.

Both python 2 and python 3 are supported.

.. _jsmin.c by Douglas Crockford:
   http://www.crockford.com/javascript/jsmin.c
"""
__author__ = "Andr\xe9 Malo"
__author__ = getattr(__author__, 'decode', lambda x: __author__)('latin-1')
__docformat__ = "restructuredtext en"
__license__ = "Apache License, Version 2.0"
__version__ = '1.0.5'
__all__ = ['jsmin']

import re as _re


def _make_jsmin(python_only=False):
    """
    Generate JS minifier based on `jsmin.c by Douglas Crockford`_

    .. _jsmin.c by Douglas Crockford:
       http://www.crockford.com/javascript/jsmin.c

    :Parameters:
      `python_only` : ``bool``
        Use only the python variant. If true, the c extension is not even
        tried to be loaded.

    :Return: Minifier
    :Rtype: ``callable``
    """
    # pylint: disable = R0912, R0914, W0612
    if not python_only:
        try:
            import _rjsmin
        except ImportError:
            pass
        else:
            return _rjsmin.jsmin
    try:
        xrange
    except NameError:
        xrange = range # pylint: disable = W0622

    space_chars = r'[\000-\011\013\014\016-\040]'

    line_comment = r'(?://[^\r\n]*)'
    space_comment = r'(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)'
    string1 = \
        r'(?:\047[^\047\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|\r)[^\047\\\r\n]*)*\047)'
    string2 = r'(?:"[^"\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|\r)[^"\\\r\n]*)*")'
    strings = r'(?:%s|%s)' % (string1, string2)

    charclass = r'(?:\[[^\\\]\r\n]*(?:\\[^\r\n][^\\\]\r\n]*)*\])'
    nospecial = r'[^/\\\[\r\n]'
    regex = r'(?:/(?![\r\n/*])%s*(?:(?:\\[^\r\n]|%s)%s*)*/)' % (
        nospecial, charclass, nospecial
    )
    space = r'(?:%s|%s)' % (space_chars, space_comment)
    newline = r'(?:%s?[\r\n])' % line_comment

    def fix_charclass(result):
        """ Fixup string of chars to fit into a regex char class """
        pos = result.find('-')
        if pos >= 0:
            result = r'%s%s-' % (result[:pos], result[pos + 1:])

        def sequentize(string):
            """
            Notate consecutive characters as sequence

            (1-4 instead of 1234)
            """
            first, last, result = None, None, []
            for char in map(ord, string):
                if last is None:
                    first = last = char
                elif last + 1 == char:
                    last = char
                else:
                    result.append((first, last))
                    first = last = char
            if last is not None:
                result.append((first, last))
            return ''.join(['%s%s%s' % (
                chr(first),
                last > first + 1 and '-' or '',
                last != first and chr(last) or ''
            ) for first, last in result])

        return _re.sub(r'([\000-\040\047])', # for better portability
            lambda m: '\\%03o' % ord(m.group(1)), (sequentize(result)
                .replace('\\', '\\\\')
                .replace('[', '\\[')
                .replace(']', '\\]')
            )
        )

    def id_literal_(what):
        """ Make id_literal like char class """
        match = _re.compile(what).match
        result = ''.join([
            chr(c) for c in xrange(127) if not match(chr(c))
        ])
        return '[^%s]' % fix_charclass(result)

    def not_id_literal_(keep):
        """ Make negated id_literal like char class """
        match = _re.compile(id_literal_(keep)).match
        result = ''.join([
            chr(c) for c in xrange(127) if not match(chr(c))
        ])
        return r'[%s]' % fix_charclass(result)

    not_id_literal = not_id_literal_(r'[a-zA-Z0-9_$]')
    preregex1 = r'[(,=:\[!&|?{};\r\n]'
    preregex2 = r'%(not_id_literal)sreturn' % locals()

    id_literal = id_literal_(r'[a-zA-Z0-9_$]')
    id_literal_open = id_literal_(r'[a-zA-Z0-9_${\[(!+-]')
    id_literal_close = id_literal_(r'[a-zA-Z0-9_$}\])"\047+-]')

    space_sub = _re.compile((
        r'([^\047"/\000-\040]+)'
        r'|(%(strings)s[^\047"/\000-\040]*)'
        r'|(?:(?<=%(preregex1)s)%(space)s*(%(regex)s[^\047"/\000-\040]*))'
        r'|(?:(?<=%(preregex2)s)%(space)s*(%(regex)s[^\047"/\000-\040]*))'
        r'|(?<=%(id_literal_close)s)'
            r'%(space)s*(?:(%(newline)s)%(space)s*)+'
            r'(?=%(id_literal_open)s)'
        r'|(?<=%(id_literal)s)(%(space)s)+(?=%(id_literal)s)'
        r'|(?<=\+)(%(space)s)+(?=\+)'
        r'|(?<=-)(%(space)s)+(?=-)'
        r'|%(space)s+'
        r'|(?:%(newline)s%(space)s*)+'
    ) % locals()).sub
    #print space_sub.__self__.pattern

    def space_subber(match):
        """ Substitution callback """
        # pylint: disable = C0321, R0911
        groups = match.groups()
        if groups[0]: return groups[0]
        elif groups[1]: return groups[1]
        elif groups[2]: return groups[2]
        elif groups[3]: return groups[3]
        elif groups[4]: return '\n'
        elif groups[5] or groups[6] or groups[7]: return ' '
        else: return ''

    def jsmin(script): # pylint: disable = W0621
        r"""
        Minify javascript based on `jsmin.c by Douglas Crockford`_\.

        Instead of parsing the stream char by char, it uses a regular
        expression approach which minifies the whole script with one big
        substitution regex.

        .. _jsmin.c by Douglas Crockford:
           http://www.crockford.com/javascript/jsmin.c

        :Parameters:
          `script` : ``str``
            Script to minify

        :Return: Minified script
        :Rtype: ``str``
        """
        return space_sub(space_subber, '\n%s\n' % script).strip()

    return jsmin

jsmin = _make_jsmin()


def jsmin_for_posers(script):
    r"""
    Minify javascript based on `jsmin.c by Douglas Crockford`_\.

    Instead of parsing the stream char by char, it uses a regular
    expression approach which minifies the whole script with one big
    substitution regex.

    .. _jsmin.c by Douglas Crockford:
       http://www.crockford.com/javascript/jsmin.c

    :Warning: This function is the digest of a _make_jsmin() call. It just
              utilizes the resulting regex. It's just for fun here and may
              vanish any time. Use the `jsmin` function instead.

    :Parameters:
      `script` : ``str``
        Script to minify

    :Return: Minified script
    :Rtype: ``str``
    """
    def subber(match):
        """ Substitution callback """
        groups = match.groups()
        return (
            groups[0] or
            groups[1] or
            groups[2] or
            groups[3] or
            (groups[4] and '\n') or
            (groups[5] and ' ') or
            (groups[6] and ' ') or
            (groups[7] and ' ') or
            ''
        )

    return _re.sub(
        r'([^\047"/\000-\040]+)|((?:(?:\047[^\047\\\r\n]*(?:\\(?:[^\r\n]|\r?'
        r'\n|\r)[^\047\\\r\n]*)*\047)|(?:"[^"\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|'
        r'\r)[^"\\\r\n]*)*"))[^\047"/\000-\040]*)|(?:(?<=[(,=:\[!&|?{};\r\n]'
        r')(?:[\000-\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/'
        r'))*((?:/(?![\r\n/*])[^/\\\[\r\n]*(?:(?:\\[^\r\n]|(?:\[[^\\\]\r\n]*'
        r'(?:\\[^\r\n][^\\\]\r\n]*)*\]))[^/\\\[\r\n]*)*/)[^\047"/\000-\040]*'
        r'))|(?:(?<=[\000-#%-,./:-@\[-^`{-~-]return)(?:[\000-\011\013\014\01'
        r'6-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))*((?:/(?![\r\n/*])[^/'
        r'\\\[\r\n]*(?:(?:\\[^\r\n]|(?:\[[^\\\]\r\n]*(?:\\[^\r\n][^\\\]\r\n]'
        r'*)*\]))[^/\\\[\r\n]*)*/)[^\047"/\000-\040]*))|(?<=[^\000-!#%&(*,./'
        r':-@\[\\^`{|~])(?:[\000-\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/'
        r'*][^*]*\*+)*/))*(?:((?:(?://[^\r\n]*)?[\r\n]))(?:[\000-\011\013\01'
        r'4\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))*)+(?=[^\000-\040"#'
        r'%-\047)*,./:-@\\-^`|-~])|(?<=[^\000-#%-,./:-@\[-^`{-~-])((?:[\000-'
        r'\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)))+(?=[^'
        r'\000-#%-,./:-@\[-^`{-~-])|(?<=\+)((?:[\000-\011\013\014\016-\040]|'
        r'(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)))+(?=\+)|(?<=-)((?:[\000-\011\0'
        r'13\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)))+(?=-)|(?:[\0'
        r'00-\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))+|(?:'
        r'(?:(?://[^\r\n]*)?[\r\n])(?:[\000-\011\013\014\016-\040]|(?:/\*[^*'
        r']*\*+(?:[^/*][^*]*\*+)*/))*)+', subber, '\n%s\n' % script
    ).strip()


if __name__ == '__main__':
    import sys as _sys
    _sys.stdout.write(jsmin(_sys.stdin.read()))
