Respect motion only when playing back (#10632)

* Respect motion only when playing back motion

* Increase efficiency

* Fix import

web/src/hooks/use-camera-activity.ts

@@ -4,6 +4,8 @@ import {
   useMotionActivity,
 } from "@/api/ws";
 import { CameraConfig } from "@/types/frigateConfig";
+import { MotionData, ReviewSegment } from "@/types/review";
+import { TimeRange } from "@/types/timeline";
 import { useEffect, useMemo, useState } from "react";
 
 type useCameraActivityReturn = {
@@ -12,7 +14,7 @@ type useCameraActivityReturn = {
   activeAudio: boolean;
 };
 
-export default function useCameraActivity(
+export function useCameraActivity(
   camera: CameraConfig,
 ): useCameraActivityReturn {
   const [activeObjects, setActiveObjects] = useState<string[]>([]);
@@ -66,3 +68,57 @@ export default function useCameraActivity(
       : false,
   };
 }
+
+export function useCameraMotionTimestamps(
+  timeRange: TimeRange,
+  motionOnly: boolean,
+  events: ReviewSegment[],
+  motion: MotionData[],
+) {
+  const timestamps = useMemo(() => {
+    const seekableTimestamps = [];
+    let lastEventIdx = 0;
+    let lastMotionIdx = 0;
+
+    for (let i = timeRange.after; i <= timeRange.before; i += 0.5) {
+      if (!motionOnly) {
+        seekableTimestamps.push(i);
+      } else {
+        const relevantEventIdx = events.findIndex((seg, segIdx) => {
+          if (segIdx < lastEventIdx) {
+            return false;
+          }
+
+          return seg.start_time <= i && seg.end_time >= i;
+        });
+
+        if (relevantEventIdx != -1) {
+          lastEventIdx = relevantEventIdx;
+          continue;
+        }
+
+        const relevantMotionIdx = motion.findIndex((mot, motIdx) => {
+          if (motIdx < lastMotionIdx) {
+            return false;
+          }
+
+          return mot.start_time <= i && mot.start_time + 15 >= i;
+        });
+
+        if (relevantMotionIdx == -1 || motion[relevantMotionIdx].motion == 0) {
+          if (relevantMotionIdx != -1) {
+            lastMotionIdx = relevantMotionIdx;
+          }
+
+          continue;
+        }
+
+        seekableTimestamps.push(i);
+      }
+    }
+
+    return seekableTimestamps;
+  }, [timeRange, motionOnly, events, motion]);
+
+  return timestamps;
+}