Implement chunkRangeIntervals() utility

src/index.ts

@@ -8,7 +8,8 @@ export { Workout, Interval, Comment } from "./ast";
 export { Duration } from "./Duration";
 export { Intensity, ConstantIntensity, RangeIntensity, FreeIntensity } from "./Intensity";
 
-// stats utils
+// utils
 export { totalDuration } from "./stats/totalDuration";
 export { intensityToZoneIndex, ZoneIndex } from "./stats/zoneDistribution";
 export { maximumIntensity } from "./stats/maximumIntensity";
+export { chunkRangeIntervals } from "./utils/chunkRangeIntervals";

src/utils/chunkRangeIntervals.test.ts

@@ -0,0 +1,154 @@
+import { Interval } from "../ast";
+import { Duration } from "../Duration";
+import { ConstantIntensity, RangeIntensity } from "../Intensity";
+import { chunkRangeIntervals } from "./chunkRangeIntervals";
+
+describe("chunkRangeIntervals()", () => {
+  const minute = new Duration(60);
+
+  it("does nothing with empty array", () => {
+    expect(chunkRangeIntervals([], minute)).toEqual([]);
+  });
+
+  it("does nothing with constant-intensity intervals", () => {
+    const intervals: Interval[] = [
+      {
+        type: "Interval",
+        duration: new Duration(2 * 60),
+        intensity: new ConstantIntensity(0.7),
+        comments: [],
+      },
+      {
+        type: "Interval",
+        duration: new Duration(10 * 60),
+        intensity: new ConstantIntensity(1),
+        comments: [],
+      },
+      {
+        type: "Rest",
+        duration: new Duration(30),
+        intensity: new ConstantIntensity(0.5),
+        comments: [],
+      },
+    ];
+
+    expect(chunkRangeIntervals(intervals, minute)).toEqual(intervals);
+  });
+
+  it("converts 1-minute range-interval to 1-minute constant-interval", () => {
+    expect(
+      chunkRangeIntervals(
+        [
+          {
+            type: "Warmup",
+            duration: minute,
+            intensity: new RangeIntensity(0.5, 1),
+            comments: [],
+          },
+        ],
+        minute,
+      ),
+    ).toMatchInlineSnapshot(`
+      Array [
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 60,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.75,
+          },
+          "type": "Warmup",
+        },
+      ]
+    `);
+  });
+
+  it("splits 3-minute range-interval to three 1-minute constant-intervals", () => {
+    expect(
+      chunkRangeIntervals(
+        [
+          {
+            type: "Warmup",
+            duration: new Duration(3 * 60),
+            intensity: new RangeIntensity(0.5, 1),
+            comments: [],
+          },
+        ],
+        minute,
+      ),
+    ).toMatchInlineSnapshot(`
+      Array [
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 60,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.5833333333333334,
+          },
+          "type": "Warmup",
+        },
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 60,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.75,
+          },
+          "type": "Warmup",
+        },
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 60,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.9166666666666667,
+          },
+          "type": "Warmup",
+        },
+      ]
+    `);
+  });
+
+  it("splits 1:30 range-interval to 1min & 30sec constant-intervals", () => {
+    expect(
+      chunkRangeIntervals(
+        [
+          {
+            type: "Warmup",
+            duration: new Duration(60 + 30),
+            intensity: new RangeIntensity(0.5, 1),
+            comments: [],
+          },
+        ],
+        minute,
+      ),
+    ).toMatchInlineSnapshot(`
+      Array [
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 60,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.6666666666666666,
+          },
+          "type": "Warmup",
+        },
+        Object {
+          "comments": Array [],
+          "duration": Duration {
+            "seconds": 30,
+          },
+          "intensity": ConstantIntensity {
+            "_value": 0.9166666666666667,
+          },
+          "type": "Warmup",
+        },
+      ]
+    `);
+  });
+});

src/utils/chunkRangeIntervals.ts

@@ -0,0 +1,49 @@
+import { chain, curry } from "ramda";
+import { Interval } from "../ast";
+import { Duration } from "../Duration";
+import { ConstantIntensity, Intensity, RangeIntensity } from "../Intensity";
+
+const chunkDuration = (seconds: number, chunkSize: Duration, intervalDuration: Duration): Duration => {
+  return seconds + chunkSize.seconds > intervalDuration.seconds
+    ? new Duration(intervalDuration.seconds % chunkSize.seconds)
+    : chunkSize;
+};
+
+const chunkIntensity = (
+  startSeconds: number,
+  chunkSize: Duration,
+  { start, end }: Intensity,
+  intervalDuration: Duration,
+): ConstantIntensity => {
+  const endSeconds =
+    startSeconds + chunkSize.seconds > intervalDuration.seconds
+      ? intervalDuration.seconds
+      : startSeconds + chunkSize.seconds;
+
+  const middleSeconds = (startSeconds + endSeconds) / 2;
+
+  return new ConstantIntensity(start + (end - start) * (middleSeconds / intervalDuration.seconds));
+};
+
+const chunkInterval = curry((chunkSize: Duration, interval: Interval): Interval[] => {
+  if (!(interval.intensity instanceof RangeIntensity)) {
+    return [interval];
+  }
+
+  const intervals: Interval[] = [];
+  for (let seconds = 0; seconds < interval.duration.seconds; seconds += chunkSize.seconds) {
+    intervals.push({
+      ...interval,
+      duration: chunkDuration(seconds, chunkSize, interval.duration),
+      intensity: chunkIntensity(seconds, chunkSize, interval.intensity, interval.duration),
+      comments: [], // TODO: for now, ignoring comments
+    });
+  }
+  return intervals;
+});
+
+/**
+ * Breaks intervals that use RangeIntensity into multiple intervals with ConstantIntensity
+ */
+export const chunkRangeIntervals = (intervals: Interval[], chunkSize: Duration): Interval[] =>
+  chain(chunkInterval(chunkSize), intervals);