feat: poll mock API server for live train positions

- positionMasters: add fetchMockTrainPositions() targeting
  /train-positions/latest on the mock API server
- useTrainMenu: when mockApiFeatureEnabled and not recording/playing,
  poll /train-positions/latest every 15s and update mockTrainPositions
  (same interval as live mode); on mode switch updates immediately
- useCurrentTrain:
  - playing: use local recording data (no network call)
  - mock ON idle: fetch from mock API server (15s poll driven by useTrainMenu)
  - mock OFF: fetch from real backend as before
- Recording still forces mock OFF so real API data is captured

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

lib/mockApi/index.ts

@@ -14,7 +14,7 @@
  */
 
 export { generateXhrInterceptorJs, MockApiConfig, TrainEntry } from './webviewXhrInterceptor';
-export { PositionMaster, PositionLookup, fetchPositionMasters, buildPosLookup, lookupPos } from './positionMasters';
+export { PositionMaster, PositionLookup, fetchPositionMasters, fetchMockTrainPositions, buildPosLookup, lookupPos } from './positionMasters';
 
 // Pre-captured sample train position data from the official site
 import trainJson from './mockData/train.json';

lib/mockApi/positionMasters.ts

@@ -14,6 +14,9 @@
 const POSITION_MASTERS_URL =
   'https://jr-shikoku-backend-mock-api-v1.haruk.in/position-masters';
 
+const MOCK_TRAIN_POSITIONS_URL =
+  'https://jr-shikoku-backend-mock-api-v1.haruk.in/train-positions/latest';
+
 export interface PositionMaster {
   pos_num: number;
   /** "yosan" | "koutoku" | "tokushima" | "dosan" | "uwajima" | "kubokawa" */
@@ -85,3 +88,14 @@ export const serializePosLookupForJs = (lookup: PositionLookup): string => {
     .join(',');
   return `{${entries}}`;
 };
+
+/**
+ * Fetch the latest train positions from the mock API server.
+ * Returns an array of TrainEntry objects (GetDateTime sentinel included).
+ * Throws on network error or non-OK response.
+ */
+export const fetchMockTrainPositions = async (): Promise<any[]> => {
+  const res = await fetch(MOCK_TRAIN_POSITIONS_URL);
+  if (!res.ok) throw new Error(`mock train-positions fetch failed: ${res.status}`);
+  return res.json();
+};

stateBox/useCurrentTrain.tsx

@@ -16,6 +16,7 @@ import { checkDuplicateTrainData } from "@/lib/checkDuplicateTrainData";
 import { getStationID } from "@/lib/eachTrainInfoCoreLib/getStationData";
 import { trainDataType } from "@/lib/trainPositionTextArray";
 import { MOCK_TRAIN_POSITIONS } from "@/lib/mockApi";
+import { fetchMockTrainPositions } from "@/lib/mockApi/positionMasters";
 import WebView from "react-native-webview";
 import { StationProps } from "@/lib/CommonTypes";
 type loading = "loading" | "success" | "error";
@@ -77,7 +78,7 @@ export const CurrentTrainProvider: FC<props> = ({ children }) => {
   const [currentTrainLoading, setCurrentTrainLoading] =
     useState<loading>("loading");
 
-  const { mockApiFeatureEnabled, mockTrainPositions, addTrainSnapshot, lookupPosText } = useTrainMenu();
+  const { mockApiFeatureEnabled, mockTrainPositions, addTrainSnapshot, lookupPosText, recorderState } = useTrainMenu();
 
   const { getInjectJavascriptAddress, stationList, originalStationList } =
     useStationList();
@@ -261,31 +262,54 @@ export const CurrentTrainProvider: FC<props> = ({ children }) => {
     }
   };
   const getCurrentTrain = () => {
-    // モックAPI機能が有効な場合はモックデータを使用
-    if (mockApiFeatureEnabled) {
+    // 再生中: 録画データをそのまま使う（ポーリング不要）
+    if (recorderState === 'playing') {
       const source = mockTrainPositions ?? MOCK_TRAIN_POSITIONS;
       const mapped = source
         .filter((x): x is import("@/lib/mockApi/webviewXhrInterceptor").TrainEntry =>
           "TrainNum" in x
         )
-        .map((x) => {
-          // Pos が空の場合は位置マスターから補完
-          const pos = x.Pos || lookupPosText(x.PosNum, x.Line) || '';
-          return {
-            Index: x.Index,
-            num: x.TrainNum,
-            delay: x.delay,
-            Pos: pos,
-            PosNum: x.PosNum,
-            Direction: x.Direction,
-            Type: x.Type,
-            Line: x.Line,
-          };
-        });
+        .map((x) => ({
+          Index: x.Index,
+          num: x.TrainNum,
+          delay: x.delay as "入線" | number,
+          Pos: x.Pos || lookupPosText(x.PosNum, x.Line) || '',
+          PosNum: x.PosNum,
+          Direction: x.Direction,
+          Type: x.Type,
+          Line: x.Line,
+        }));
       setCurrentTrain(mapped);
       setCurrentTrainLoading("success");
       return;
     }
+
+    // モックON（通常）: モックAPIサーバーをポーリング
+    if (mockApiFeatureEnabled) {
+      const controller = new AbortController();
+      const timeoutId = setTimeout(() => controller.abort(), 8000);
+      fetchMockTrainPositions()
+        .then((data) => {
+          const entries = data.filter((x: any) => "TrainNum" in x);
+          const mapped = entries.map((x: any) => ({
+            Index: x.Index as number,
+            num: x.TrainNum as string,
+            delay: x.delay as "入線" | number,
+            Pos: (x.Pos || lookupPosText(x.PosNum, x.Line) || '') as string,
+            PosNum: x.PosNum as number,
+            Direction: x.Direction as number,
+            Type: x.Type as string,
+            Line: x.Line as string,
+          }));
+          setCurrentTrain(mapped);
+          setCurrentTrainLoading("success");
+        })
+        .catch(() => {
+          setCurrentTrainLoading("error");
+        })
+        .finally(() => clearTimeout(timeoutId));
+      return;
+    }
     const controller = new AbortController();
     const timeoutId = setTimeout(() => controller.abort(), 8000);
     fetch("https://n8n.haruk.in/webhook/c501550c-7d1b-4e50-927b-4429fe18931a", { signal: controller.signal })

stateBox/useTrainMenu.tsx

@@ -4,6 +4,7 @@ import React, {
   useState,
   useEffect,
   useRef,
+  useCallback,
   FC,
 } from "react";
 
@@ -18,6 +19,7 @@ import {
   PositionMaster,
   PositionLookup,
   fetchPositionMasters,
+  fetchMockTrainPositions,
   buildPosLookup,
   lookupPos,
 } from "../lib/mockApi/positionMasters";
@@ -387,10 +389,30 @@ export const TrainMenuProvider: FC<props> = ({ children }) => {
     AS.getItem(STORAGE_KEYS.JR_DATA_SYSTEM_ENV).then((value) => {
       setBackendApiBaseUrl(getBackendApiBaseUrl(value));
     }).catch(() => {});
-    // サンプルデータで初期化
+    // 静的サンプルデータで初期化（モックAPIが応答するまでのフォールバック）
     setMockTrainPositions(MOCK_TRAIN_POSITIONS);
   }, []);
 
+  // モックAPIポーリング: モックON かつ 録画/再生中でない場合に15秒ごとに更新
+  const fetchAndSetMockPositions = useCallback(() => {
+    if (!mockApiFeatureEnabled || recorderState !== 'idle') return;
+    fetchMockTrainPositions()
+      .then((data) => {
+        const entries = data.filter((x: any) => "TrainNum" in x) as TrainEntry[];
+        setMockTrainPositions(entries);
+      })
+      .catch(() => {});
+  }, [mockApiFeatureEnabled, recorderState]);
+
+  useEffect(() => {
+    if (!mockApiFeatureEnabled || recorderState !== 'idle') return;
+    // 即時取得
+    fetchAndSetMockPositions();
+    // 15秒ごとにポーリング
+    const timer = setInterval(fetchAndSetMockPositions, 15000);
+    return () => clearInterval(timer);
+  }, [mockApiFeatureEnabled, recorderState]);
+
   return (
     <TrainMenuContext.Provider
       value={{