"""
Program that grabs the specific lecture URLs from
the CS51A course home page
"""

# David Kauchak

from urllib.request import urlopen

COURSE_PAGE = "http://www.cs.pomona.edu/~dkauchak/classes/cs51a/"

def get_note_urls(page):
    """
    Get the lecture URLs available from the course web page and
    return them in a list
    """
    web_page = urlopen(page)
    
    urls = []
    
    # all of the urls for lectures, start with "lectures/"
    search_line = "lectures/"
    
    for line in web_page:
        line = line.decode('ISO-8859-1').strip()
        
        if search_line in line:
            begin_index = line.find(search_line)
            end_index = line.find('"', begin_index)
            urls.append(page + line[begin_index:end_index])
    
    return urls

def write_list_to_file(some_list, output_file):
    """Write out all of the contents of the list to the file"""
    out = open(output_file, "w")
    out.write("Lecture notes for CS51A\n\n")
    
    for item in some_list:
        out.write(item + "\n")
        
    out.close()

def write_lecture(outfile):
    # get the lecture urls
    lecture_urls = get_note_urls(COURSE_PAGE)
    # print them out to the file
    write_list_to_file(lecture_urls, outfile)