#!/usr/bin/env python
from __future__ import absolute_import
from __future__ import print_function

import os
import glob
import subprocess
import sys
import time

sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
os.environ['DJANGO_SETTINGS_MODULE'] = 'zproject.settings'
from django.conf import settings

from typing import Dict, List

os.chdir(settings.DEPLOY_ROOT)
STATIC_PATH = 'static/'

def get_templates():
    # type: () -> List[str]
    return (glob.glob(os.path.join(STATIC_PATH, 'templates/*.handlebars')) +
        glob.glob(os.path.join(STATIC_PATH, 'templates/settings/*.handlebars')))

def run():
    # type: () -> None
    subprocess.check_call(['tools/node', 'node_modules/.bin/handlebars']
        + get_templates()
        + ['--output', os.path.join(STATIC_PATH, 'templates/compiled.js'),
           '--known', 'if,unless,each,with'])

def run_forever():
    # type: () -> None
    # Keep polling for file changes, similar to how Django does it in
    # django/utils/autoreload.py.  If any of our templates change, rebuild
    # compiled.js
    mtimes = {} # type: Dict[str, float]
    while True:
        changed = False
        for fn in get_templates():
            new_mtime = os.stat(fn).st_mtime
            if new_mtime != mtimes.get(fn, None):
                changed = True
            mtimes[fn] = new_mtime
        if changed:
            print('Recompiling templates')
            try:
                run()
                print('done')
            except:
                print('\n\n\nPLEASE FIX!!\n\n')
        time.sleep(0.200)

if __name__ == '__main__':
    if len(sys.argv) == 2 and sys.argv[1] == 'forever':
        try:
            run_forever()
        except KeyboardInterrupt:
            print(sys.argv[0], "exited after receiving KeyboardInterrupt")
    else:
        run()