🎨 Reorganize back-end code

backend/api/idfm_interface/idfm_interface.py

@@ -0,0 +1,115 @@
+from collections import defaultdict
+from re import compile as re_compile
+from typing import ByteString
+
+from aiofiles import open as async_open
+from aiohttp import ClientSession
+from msgspec import ValidationError
+from msgspec.json import Decoder
+
+from .idfm_types import Destinations as IdfmDestinations, IdfmResponse, IdfmState
+from db import Database
+from models import Line, Stop, StopArea
+
+
+class IdfmInterface:
+
+    IDFM_ROOT_URL = "https://prim.iledefrance-mobilites.fr/marketplace"
+    IDFM_STOP_MON_URL = f"{IDFM_ROOT_URL}/stop-monitoring"
+
+    OPERATOR_RE = re_compile(r"[^:]+:Operator::([^:]+):")
+    LINE_RE = re_compile(r"[^:]+:Line::C([^:]+):")
+
+    def __init__(self, api_key: str, database: Database) -> None:
+        self._api_key = api_key
+        self._database = database
+
+        self._http_headers = {"Accept": "application/json", "apikey": self._api_key}
+
+        self._response_json_decoder = Decoder(type=IdfmResponse)
+
+    async def startup(self) -> None:
+        ...
+
+    @staticmethod
+    def _format_line_id(line_id: str) -> int:
+        return int(line_id[1:] if line_id[0] == "C" else line_id)
+
+    async def render_line_picto(self, line: Line) -> tuple[None | str, None | str]:
+        line_picto_path = line_picto_format = None
+        target = f"/tmp/{line.id}_repr"
+
+        picto = line.picto
+        if picto is not None:
+            if (picto_data := await self._get_line_picto(line)) is not None:
+                async with async_open(target, "wb") as fd:
+                    await fd.write(bytes(picto_data))
+                line_picto_path = target
+                line_picto_format = picto.mime_type
+
+        return (line_picto_path, line_picto_format)
+
+    async def _get_line_picto(self, line: Line) -> ByteString | None:
+        data = None
+
+        picto = line.picto
+        if picto is not None and picto.url is not None:
+            headers = (
+                self._http_headers if picto.url.startswith(self.IDFM_ROOT_URL) else None
+            )
+
+            async with ClientSession(headers=headers) as session:
+                async with session.get(picto.url) as response:
+                    data = await response.read()
+
+        return data
+
+    async def get_next_passages(self, stop_point_id: int) -> IdfmResponse | None:
+        ret = None
+        params = {"MonitoringRef": f"STIF:StopPoint:Q:{stop_point_id}:"}
+
+        async with ClientSession(headers=self._http_headers) as session:
+            async with session.get(self.IDFM_STOP_MON_URL, params=params) as response:
+
+                if response.status == 200:
+                    data = await response.read()
+                    try:
+                        ret = self._response_json_decoder.decode(data)
+                    except ValidationError as err:
+                        print(err)
+
+        return ret
+
+    async def get_destinations(self, stop_id: int) -> IdfmDestinations | None:
+        destinations: IdfmDestinations = defaultdict(set)
+
+        if (stop := await Stop.get_by_id(stop_id)) is not None:
+            expected_stop_ids = {stop.id}
+        elif (stop_area := await StopArea.get_by_id(stop_id)) is not None:
+            expected_stop_ids = {stop.id for stop in stop_area.stops}
+        else:
+            return None
+
+        if (res := await self.get_next_passages(stop_id)) is not None:
+
+            for delivery in res.Siri.ServiceDelivery.StopMonitoringDelivery:
+                if delivery.Status == IdfmState.true:
+                    for stop_visit in delivery.MonitoredStopVisit:
+
+                        monitoring_ref = stop_visit.MonitoringRef.value
+
+                        try:
+                            monitored_stop_id = int(monitoring_ref.split(":")[-2])
+                        except (IndexError, ValueError):
+                            print(f"Unable to get stop id from {monitoring_ref}")
+                            continue
+
+                        journey = stop_visit.MonitoredVehicleJourney
+                        if (
+                            dst_names := journey.DestinationName
+                        ) and monitored_stop_id in expected_stop_ids:
+                            raw_line_id = journey.LineRef.value.split(":")[-2]
+                            line_id = IdfmInterface._format_line_id(raw_line_id)
+                            destinations[line_id].add(dst_names[0].value)
+
+        return destinations