
# Retrieved from ansible.module_utils.basic. It's better to use the original one,
# but its package recently changed, so decided to have another one.
def json_dict_unicode_to_bytes(d):
    ''' Recursively convert dict keys and values to byte str

        Specialized for json return because this only handles, lists, tuples,
        and dict container types (the containers that the json module returns)
    '''

    if isinstance(d, unicode):
        return d.encode('utf-8')
    elif isinstance(d, dict):
        return dict(map(json_dict_unicode_to_bytes, d.iteritems()))
    elif isinstance(d, list):
        return list(map(json_dict_unicode_to_bytes, d))
    elif isinstance(d, tuple):
        return tuple(map(json_dict_unicode_to_bytes, d))
    else:
        return d

# Retrieved from ansible.module_utils.splitter. It's better to use the original one,
# but ansible's old versions do not have it, so decided to have another one.
def _count_jinja2_blocks(token, cur_depth, open_token, close_token):
    '''
    this function counts the number of opening/closing blocks for a
    given opening/closing type and adjusts the current depth for that
    block based on the difference
    '''
    num_open  = token.count(open_token)
    num_close = token.count(close_token)
    if num_open != num_close:
        cur_depth += (num_open - num_close)
        if cur_depth < 0:
            cur_depth = 0
    return cur_depth

def _get_quote_state(token, quote_char):
    '''
    the goal of this block is to determine if the quoted string
    is unterminated in which case it needs to be put back together
    '''
    # the char before the current one, used to see if
    # the current character is escaped
    prev_char = None
    for idx, cur_char in enumerate(token):
        if idx > 0:
            prev_char = token[idx-1]
        if cur_char in '"\'' and prev_char != '\\':
            if quote_char:
                if cur_char == quote_char:
                    quote_char = None
            else:
                quote_char = cur_char
    return quote_char

def split_args(args):
    '''
    Splits args on whitespace, but intelligently reassembles
    those that may have been split over a jinja2 block or quotes.

    When used in a remote module, we won't ever have to be concerned about
    jinja2 blocks, however this function is/will be used in the
    core portions as well before the args are templated.

    example input: a=b c="foo bar"
    example output: ['a=b', 'c="foo bar"']

    Basically this is a variation shlex that has some more intelligence for
    how Ansible needs to use it.
    '''

    # the list of params parsed out of the arg string
    # this is going to be the result value when we are donei
    params = []

    # here we encode the args, so we have a uniform charset to
    # work with, and split on white space
    args = args.strip()
    try:
        args = args.encode('utf-8')
        do_decode = True
    except UnicodeDecodeError:
        do_decode = False
    items = args.split('\n')

    # iterate over the tokens, and reassemble any that may have been
    # split on a space inside a jinja2 block.
    # ex if tokens are "{{", "foo", "}}" these go together

    # These variables are used
    # to keep track of the state of the parsing, since blocks and quotes
    # may be nested within each other.

    quote_char = None
    inside_quotes = False
    print_depth   = 0 # used to count nested jinja2 {{ }} blocks
    block_depth   = 0 # used to count nested jinja2 {% %} blocks
    comment_depth = 0 # used to count nested jinja2 {# #} blocks

    # now we loop over each split chunk, coalescing tokens if the white space
    # split occurred within quotes or a jinja2 block of some kind
    for itemidx,item in enumerate(items):

        # we split on spaces and newlines separately, so that we
        # can tell which character we split on for reassembly
        # inside quotation characters
        tokens = item.strip().split(' ')

        line_continuation = False
        for idx,token in enumerate(tokens):

            # if we hit a line continuation character, but
            # we're not inside quotes, ignore it and continue
            # on to the next token while setting a flag
            if token == '\\' and not inside_quotes:
                line_continuation = True
                continue

            # store the previous quoting state for checking later
            was_inside_quotes = inside_quotes
            quote_char = _get_quote_state(token, quote_char)
            inside_quotes = quote_char is not None

            # multiple conditions may append a token to the list of params,
            # so we keep track with this flag to make sure it only happens once
            # append means add to the end of the list, don't append means concatenate
            # it to the end of the last token
            appended = False

            # if we're inside quotes now, but weren't before, append the token
            # to the end of the list, since we'll tack on more to it later
            # otherwise, if we're inside any jinja2 block, inside quotes, or we were
            # inside quotes (but aren't now) concat this token to the last param
            if inside_quotes and not was_inside_quotes:
                params.append(token)
                appended = True
            elif print_depth or block_depth or comment_depth or inside_quotes or was_inside_quotes:
                if idx == 0 and not inside_quotes and was_inside_quotes:
                    params[-1] = "%s%s" % (params[-1], token)
                elif len(tokens) > 1:
                    spacer = ''
                    if idx > 0:
                        spacer = ' '
                    params[-1] = "%s%s%s" % (params[-1], spacer, token)
                else:
                    spacer = ''
                    if not params[-1].endswith('\n') and idx == 0:
                        spacer = '\n'
                    params[-1] = "%s%s%s" % (params[-1], spacer, token)
                appended = True

            # if the number of paired block tags is not the same, the depth has changed, so we calculate that here
            # and may append the current token to the params (if we haven't previously done so)
            prev_print_depth = print_depth
            print_depth = _count_jinja2_blocks(token, print_depth, "{{", "}}")
            if print_depth != prev_print_depth and not appended:
                params.append(token)
                appended = True

            prev_block_depth = block_depth
            block_depth = _count_jinja2_blocks(token, block_depth, "{%", "%}")
            if block_depth != prev_block_depth and not appended:
                params.append(token)
                appended = True

            prev_comment_depth = comment_depth
            comment_depth = _count_jinja2_blocks(token, comment_depth, "{#", "#}")
            if comment_depth != prev_comment_depth and not appended:
                params.append(token)
                appended = True

            # finally, if we're at zero depth for all blocks and not inside quotes, and have not
            # yet appended anything to the list of params, we do so now
            if not (print_depth or block_depth or comment_depth) and not inside_quotes and not appended and token != '':
                params.append(token)

        # if this was the last token in the list, and we have more than
        # one item (meaning we split on newlines), add a newline back here
        # to preserve the original structure
        if len(items) > 1 and itemidx != len(items) - 1 and not line_continuation:
            if not params[-1].endswith('\n') or item == '':
                params[-1] += '\n'

        # always clear the line continuation flag
        line_continuation = False

    # If we're done and things are not at zero depth or we're still inside quotes,
    # raise an error to indicate that the args were unbalanced
    if print_depth or block_depth or comment_depth or inside_quotes:
        raise Exception("error while splitting arguments, either an unbalanced jinja2 block or quotes")

    # finally, we decode each param back to the unicode it was in the arg string
    if do_decode:
        params = [x.decode('utf-8') for x in params]

    return params
