haldis/app/hlds/parser.py
2020-10-12 22:41:27 +02:00

151 lines
4.9 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)]
class ChoiceReference:
def __init__(self, identifier, price):
self.identifier = identifier
self.price = price
# 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: Iterable[Dish] = filter_instance(Dish, ast["items_"])
for dish in dishes:
for i, choice in enumerate(dish.choices):
if not isinstance(choice[1], Choice):
choiceId, choiceRef = choice
assert isinstance(choiceRef, ChoiceReference)
# We must replace the ChoiceReference with the Choice it refers to. A deep copy
# allows us to modify the individual Options of the Choice.
choiceObject = deepcopy(choices[choiceRef.identifier])
for option in choiceObject.options:
option.price += choiceRef.price
dish.choices[i] = (choiceId, choiceObject)
# Move the base price to the first single_choice if the dish doesn't have a fixed price
first_single_choice = first(
c[1] for c in dish.choices if c[0] == "single_choice"
)
price_range = dish.price_range()
if dish.price and price_range[0] != price_range[1] 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("phone"),
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 block definitions 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]]:
if ast["kind"] == "declaration":
return (ast["type"], self.choice_block(ast))
else:
if ast["type"] == "single_choice" and ast["price"]:
raise SemanticError(
"Single_choice choices can't have a price, because it would always be triggered"
)
return (ast["type"], ChoiceReference(ast["id"], ast["price"] or 0))
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"] or [],
)
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)