create_menu.py

#!/usr/bin/python3
"""
    Creates a menu from a tab-delimited text file.
"""

import sys
from pylib.parse_site import parse_site, InputError
from pylib.html_tags import sidebar, sidebar_links

TITLE = 0  # type: int
INPUT = 1  # type: int
OUTPUT = 2  # type: int
EMPTY_LIST = 1  # type: int
INDENT_MISMATCH = 2  # type: int
BAD_ARGS = 3  # type: int

INDENT = "    "  # type: str

TOT_SUBMENUS = 0  # type: int


def get_pad(level):
    """
        Get padding amount.
    """
    return INDENT * level


def create_link(topic, level, is_url):
    """
        Creates a link in the sidebar.
    """
    global TOT_SUBMENUS
    padding = get_pad(level + 1)
    return sidebar_links(padding=padding, topic=topic,
                         tot_submenus=TOT_SUBMENUS, is_url=is_url)


def process_menu(topics, level):
    """
        Processes a menu level.
    """
    global TOT_SUBMENUS
    menu_txt = ""
    padding = get_pad(level)
    if level == 1:
        menu_txt += "%s<ul class=\"list-unstyled components\">\n" % padding
    else:
        menu_txt += ('%s<ul class="collapse list-unstyled" id="Submenu%d">\n'
                     % (padding, TOT_SUBMENUS))
        TOT_SUBMENUS += 1

    for topic in topics:
        if topic.url is not None:
            menu_txt += create_link(topic, level, True)
        else:
            if topic.subtopics is not None:
                menu_txt += create_link(topic, level, False)
                menu_txt += process_menu(topic.subtopics, level + 1)
    menu_txt += "%s</ul>\n" % padding
    return menu_txt


if len(sys.argv) < 2:
    print("ERROR: Please specify input file name.")
    sys.exit(BAD_ARGS)

INPUT_FNAME = sys.argv[INPUT]  # type: str

TITLE = None
COURSE_ITEMS = None

try:
    (TITLE, COURSE_ITEMS) = parse_site(INPUT_FNAME)
except InputError as input_err:
    print("ERROR: Input error at %s: %s" % (input_err.value, input_err.msg))
    sys.exit()

# for debugging:
# for course_item in course_items:
#     print(course_item)

if not COURSE_ITEMS:
    print("WARNING: Empty input file.")
    sys.exit()

# title is required
if TITLE.level != 0:
    print("ERROR: Title indent level is: " + str(TITLE.level))
    sys.exit()
elif TITLE.short_title is None:
    print("ERROR: Short title is required for navbar title.")
    sys.exit()

S = sidebar(title=TITLE.title, short_title=TITLE.short_title,
            menu_txt=process_menu(COURSE_ITEMS, 1))

# write generated sidebar
print(S, end="")