haldis/app/hlds/parser.py

127 lines
3.9 KiB
Python

#!/usr/bin/env python3
from glob import glob
from os import path
import itertools
from copy import deepcopy
from typing import Iterable, List, Union, Tuple
from tatsu import parse as tatsu_parse
from tatsu.ast import AST
from tatsu.exceptions import SemanticError
from .models import Location, Choice, Option, Dish
from utils import first
# TODO Use proper way to get resources, see https://stackoverflow.com/a/10935674
with open(path.join(path.dirname(__file__), "hlds.tatsu")) as fh:
GRAMMAR = fh.read()
def filter_instance(cls, iterable):
return [item for item in iterable if isinstance(item, cls)]
# pylint: disable=no-self-use
class HldsSemanticActions:
def location(self, ast) -> Location:
choices = {choice.id: choice for choice in filter_instance(Choice, ast["items_"])}
dishes = filter_instance(Dish, ast["items_"])
for dish in dishes:
for i, choice in enumerate(dish.choices):
if not isinstance(choice[1], Choice):
dish.choices[i] = (dish.choices[i][0], deepcopy(choices[choice[1]]))
# Move the base price to the first single choice if there is any
first_single_choice = first(c[1] for c in dish.choices if c[0] == "single_choice")
if dish.price and first_single_choice:
for option in first_single_choice.options:
option.price += dish.price
dish.price = 0
attributes = {att["key"]: att["value"] for att in ast["attributes"]}
return Location(
ast["id"],
name=ast["name"],
dishes=dishes,
osm=attributes.get("osm"),
address=attributes.get("address"),
telephone=attributes.get("telephone"),
website=attributes.get("website"),
)
def dish_block(self, ast) -> Dish:
return Dish(
ast["id"],
name=ast["name"],
description=ast["description"],
price=ast["price"] or 0,
tags=ast["tags"] or [],
choices=ast["choices"],
)
def choice_block(self, ast) -> Choice:
if ast["price"] or ast["tags"]:
raise SemanticError("Choice blocks cannot have price or tags, put them on each of its options instead")
return Choice(
ast["id"],
name=ast["name"],
description=ast["description"],
options=ast["entries"],
)
def indent_choice_block(self, ast) -> Tuple[str, Union[Choice, AST]]:
return (
(ast["type"], self.choice_block(ast))
if ast["kind"] == "declaration" else
(ast["type"], ast["id"])
)
def indent_choice_entry(self, ast) -> Option:
return Option(
ast["id"],
name=ast["name"],
description=ast["description"],
price=ast["price"] or 0,
tags=ast["tags"],
)
noindent_choice_entry = indent_choice_entry
def price(self, ast) -> int:
return (
100 * int(ast["value_unit"]) +
(
0 if not ast["value_cents"] else
10 * int(ast["value_cents"]) if len(ast["value_cents"]) == 1 else
int(ast["value_cents"])
)
)
def _default(self, ast):
return ast
SEMANTICS = HldsSemanticActions()
def parse(menu: str) -> List[Location]:
parsed = tatsu_parse(GRAMMAR, menu, semantics=SEMANTICS)
return parsed
def parse_file(filename: str) -> List[Location]:
with open(filename, "r") as file_handle:
return parse(file_handle.read())
def parse_files(files: Iterable[str]) -> List[Location]:
menus = map(parse_file, files)
return list(itertools.chain.from_iterable(menus))
def parse_all_directory(directory: str) -> List[Location]:
# TODO Use proper way to get resources, see https://stackoverflow.com/a/10935674
files = glob(path.join(directory, "**.hlds"), recursive=True)
return parse_files(files)