#!/usr/bin/env python
from __future__ import absolute_import
from __future__ import print_function
from lib.template_parser import validate
import optparse
import sys

from six.moves import filter
try:
    import lister
    from typing import cast, Callable, Dict, Iterable, List
except ImportError as e:
    print("ImportError: {}".format(e))
    print("You need to run the Zulip linters inside a Zulip dev environment.")
    print("If you are using Vagrant, you can `vagrant ssh` to enter the Vagrant guest.")
    sys.exit(1)

def check_our_files():
    # type: () -> None
    parser = optparse.OptionParser()
    parser.add_option('--modified', '-m',
        action='store_true', default=False,
        help='Only check modified files')
    (options, _) = parser.parse_args()

    by_lang = cast(
        Dict[str, List[str]],
        lister.list_files(
            modified_only=options.modified,
            ftypes=['handlebars', 'html'],
            group_by_ftype=True))

    check_handlebar_templates(by_lang['handlebars'], options.modified)
    check_html_templates(by_lang['html'], options.modified)

def check_html_templates(templates, modified_only):
    # type: (Iterable[str], bool) -> None
    # Our files with .html extensions are usually for Django, but we also
    # have a few static .html files.
    # The file base.html has a bit of funny HTML that we can't parse here yet.
    #
    # We also have .html files that we vendored from Casper.
    # The casperjs files use HTML5 (whereas Zulip prefers XHTML), and
    # there are also cases where Casper deliberately uses invalid HTML,
    # so we exclude them from our linter.
    templates = filter(
        lambda fn: ('base.html' not in fn) and ('casperjs' not in fn),
        templates)
    templates = sorted(list(templates))

    if not modified_only:
        assert len(templates) >= 10 # sanity check that we are actually doing work
    for fn in templates:
        # Many of our Django templates have strange indentation.  The
        # indentation errors are often harmless, even stylistically
        # harmless, but they tend to be in files that might be old
        # and might eventually require more scrutiny for things like
        # localization.  See github #1236.
        bad_files = [
            'static/html/5xx.html',
            'templates/500.html',
            'templates/confirmation/confirm.html',
            'templates/corporate/mit.html',
            'templates/corporate/privacy.html',
            'templates/corporate/terms-enterprise.html',
            'templates/corporate/zephyr-mirror.html',
            'templates/corporate/zephyr.html',
            'templates/zerver/accounts_home.html',
            'templates/zerver/accounts_send_confirm.html',
            'templates/zerver/api.html',
            'templates/zerver/api_endpoints.html',
            'templates/zerver/apps.html',
            'templates/zerver/create_realm.html',
            'templates/zerver/emails/followup/day1.html',
            'templates/zerver/emails/followup/day2.html',
            'templates/zerver/features.html',
            'templates/zerver/hello.html',
            'templates/zerver/home.html',
            'templates/zerver/integrations.html',
            'templates/zerver/invite_user.html',
            'templates/zerver/left-sidebar.html',
            'templates/zerver/login.html',
            'templates/zerver/markdown_help.html',
            'templates/zerver/register.html',
            'templates/zerver/right-sidebar.html',
            'templates/zerver/search_operators.html',
        ]
        validate(fn=fn, check_indent=(fn not in bad_files))

def check_handlebar_templates(templates, modified_only):
    # type: (Iterable[str], bool) -> None
    # Check all our handlebars templates.
    templates = [fn for fn in templates if fn.endswith('.handlebars')]
    if not modified_only:
        assert len(templates) >= 10 # sanity check that we are actually doing work
    for fn in templates:
        validate(fn=fn, check_indent=True)

if __name__ == '__main__':
    check_our_files()