#!/usr/bin/env python3
import os
from io import TextIOWrapper
import sys

NAVBAR_FMT = '''
<ul>
  <li><a href="index.html">
    Home{}
  </a></li>
  <li><a href="projects.html">
    Projects{}
  </a></li>
  <li><a href="about.html">
    About & Contact{}
  </a></li>
</ul>
'''
SELECT_FMT = ' &lt;'
current_source = ''


def token_to_str(token: str) -> str:
    global current_source

    if token == 'NAVBAR':
        home_str = ''
        projects_str = ''
        about_str = ''

        if current_source == 'index.html':
            home_str = SELECT_FMT
        elif current_source == 'projects.html':
            projects_str = SELECT_FMT
        elif current_source == 'about.html':
            about_str = SELECT_FMT

        return NAVBAR_FMT.format(home_str, projects_str, about_str)
    elif token.endswith('.html'):
        return open('includes/' + token).read()
    else:
        return '{{' + token + '}}'


def replace_line(line: str) -> (str, int):
    ret = ''
    count = 0

    replacing = False
    token = ''
    i = 0
    while i < (len(line) - 2):
        if replacing:
            if line[i:i+2] == r'}}':
                replacing = False
                ret += token_to_str(token)
                i += 2
                token = ''
                count += 1
            else:
                token += line[i]
                i += 1
        else:
            if line[i:i+2] == r'{{':
                replacing = True
                i += 2
            else:
                ret += line[i]
                i += 1

    if replacing:
        ret += '{{' + token
    ret += line[i:]

    return (ret, count)

def stream_template(in_fd: TextIOWrapper, out_fd: TextIOWrapper) -> int:
    replacements = 0

    while True:
        line = in_fd.readline()
        if line == '':
            break

        new_line, count = replace_line(line)
        out_fd.write(new_line)
        replacements += count

    return replacements


def main():
    global current_source

    includes = os.listdir('includes')
    sources = os.listdir('src')

    print(includes)
    print(sources)

    if not os.path.isdir('public'):
        os.mkdir('public')

    for source in sources:
        current_source = source

        in_fd = open('src/' + source, 'r')
        out_fd = open('public/' + source, 'w')
        stream_template(in_fd, out_fd)

if __name__ == '__main__':
    main()