Cue support

packages/stitcher/src/interstitials.ts

@@ -1,6 +1,6 @@
 import { createUrl } from "./lib/url";
 import { getAssetsFromVast } from "./vast";
-import type { DateRange } from "./parser";
+import type { CueOut, DateRange, MediaPlaylist } from "./parser";
 import type { Session } from "./session";
 import type { Interstitial, InterstitialAsset } from "./types";
 import type { DateTime } from "luxon";
@@ -112,3 +112,29 @@ function getTimelineStyle(interstitial: Interstitial) {
   }
   return "PRIMARY";
 }
+
+export function insertInterstitialsFromCuesMap(
+  cuesMap: {
+    dateTime: DateTime;
+    cueOut: CueOut;
+  }[],
+  media: MediaPlaylist,
+) {
+  for (const item of cuesMap) {
+    const clientAttributes: Record<string, number | string> = {
+      RESTRICT: "SKIP,JUMP",
+      "ASSET-LIST": createUrl("out/asset-list.json", {
+        dt: item.dateTime.toISO(),
+        sid: "live",
+      }),
+      // "PLAYOUT-LIMIT": item.cueOut.duration,
+    };
+
+    media.dateRanges.push({
+      classId: "com.apple.hls.interstitial",
+      id: `${item.dateTime.toMillis()}`,
+      startDate: item.dateTime.minus({ milliseconds: 1 }),
+      clientAttributes,
+    });
+  }
+}

packages/stitcher/src/parser/lexical-parse.ts

@@ -19,6 +19,7 @@ const EMPTY_TAGS = [
   "EXT-X-ENDLIST",
   "EXT-X-I-FRAMES-ONLY",
   "EXT-X-INDEPENDENT-SEGMENTS",
+  "EXT-X-CUE-IN",
 ] as const;
 
 const NUMBER_TAGS = [
@@ -40,7 +41,12 @@ export type Tag =
   | ["EXT-X-STREAM-INF", StreamInf]
   | ["EXT-X-MEDIA", Media]
   | ["EXT-X-MAP", MediaInitializationSection]
-  | ["EXT-X-DATERANGE", DateRange];
+  | ["EXT-X-DATERANGE", DateRange]
+  | ["EXT-X-CUE-OUT", CueOut];
+
+export interface CueOut {
+  duration: number;
+}
 
 export interface ExtInf {
   duration: number;
@@ -276,6 +282,29 @@ function parseLine(line: string): Tag | null {
       ];
     }
 
+    case "EXT-X-CUE-OUT": {
+      assert(param, "EXT-X-CUE-OUT: no param");
+
+      const attrs: Partial<CueOut> = {};
+
+      mapAttributes(param, (key, value) => {
+        switch (key) {
+          case "DURATION":
+            attrs.duration = Number.parseFloat(value);
+            break;
+        }
+      });
+
+      assert(attrs.duration, "EXT-X-CUE-OUT: no duration");
+
+      return [
+        name,
+        {
+          duration: attrs.duration,
+        },
+      ];
+    }
+
     default:
       return null;
   }

packages/stitcher/src/parser/parse.ts

@@ -2,6 +2,7 @@ import { assert } from "shared/assert";
 import { lexicalParse } from "./lexical-parse";
 import type { Tag } from "./lexical-parse";
 import type {
+  CueOut,
   DateRange,
   MasterPlaylist,
   MediaInitializationSection,
@@ -94,7 +95,9 @@ function formatMediaPlaylist(tags: Tag[]): MediaPlaylist {
       map = value;
     }
 
-    if (isSegmentTag(name)) {
+    // TODO: We can have multiple tags covering a segment, do not select
+    // a new segmentStart when we already have one. This merely means there are multiple.
+    if (isSegmentTag(name) && segmentStart === -1) {
       segmentStart = index - 1;
     }
 
@@ -146,6 +149,9 @@ function isSegmentTag(name: Tag[0]) {
     case "EXTINF":
     case "EXT-X-DISCONTINUITY":
     case "EXT-X-PROGRAM-DATE-TIME":
+    case "EXT-X-CUE-OUT":
+    case "EXT-X-CUE-IN":
+    case "EXT-X-MAP":
       return true;
   }
   return false;
@@ -159,6 +165,8 @@ function parseSegment(
   let duration: number | undefined;
   let discontinuity: boolean | undefined;
   let programDateTime: DateTime | undefined;
+  let cueOut: CueOut | undefined;
+  let cueIn: boolean | undefined;
 
   tags.forEach(([name, value]) => {
     if (name === "EXTINF") {
@@ -170,6 +178,12 @@ function parseSegment(
     if (name === "EXT-X-PROGRAM-DATE-TIME") {
       programDateTime = value;
     }
+    if (name === "EXT-X-CUE-OUT") {
+      cueOut = value;
+    }
+    if (name === "EXT-X-CUE-IN") {
+      cueIn = true;
+    }
   });
 
   assert(duration, "parseSegment: duration not found");
@@ -180,6 +194,8 @@ function parseSegment(
     discontinuity,
     map,
     programDateTime,
+    cueOut,
+    cueIn,
   };
 }
 

packages/stitcher/src/parser/stringify.ts

@@ -116,6 +116,14 @@ export function stringifyMediaPlaylist(playlist: MediaPlaylist) {
       lines.push(`#EXT-X-DISCONTINUITY`);
     }
 
+    if (segment.cueOut) {
+      lines.push(`#EXT-X-CUE-OUT:DURATION=${segment.cueOut.duration}`);
+    }
+
+    if (segment.cueIn) {
+      lines.push("#EXT-X-CUE-IN");
+    }
+
     if (segment.programDateTime) {
       lines.push(`#EXT-X-PROGRAM-DATE-TIME:${segment.programDateTime.toISO()}`);
     }

packages/stitcher/src/parser/types.ts

@@ -33,12 +33,18 @@ export interface MediaInitializationSection {
   uri: string;
 }
 
+export interface CueOut {
+  duration: number;
+}
+
 export interface Segment {
   uri: string;
   duration: number;
   discontinuity?: boolean;
   map?: MediaInitializationSection;
   programDateTime?: DateTime;
+  cueOut?: CueOut;
+  cueIn?: boolean;
 }
 
 export type PlaylistType = "EVENT" | "VOD";

packages/stitcher/src/playlist.ts

@@ -3,6 +3,7 @@ import { filterMasterPlaylist, formatFilterToQueryParam } from "./filters";
 import {
   getAssets,
   getStaticDateRanges,
+  insertInterstitialsFromCuesMap,
   mergeInterstitials,
 } from "./interstitials";
 import { encrypt } from "./lib/crypto";
@@ -14,9 +15,10 @@ import {
   stringifyMediaPlaylist,
 } from "./parser";
 import { updateSession } from "./session";
+import { getAssetsFromVast } from "./vast";
 import { fetchVmap, toAdBreakTimeOffset } from "./vmap";
 import type { Filter } from "./filters";
-import type { MasterPlaylist, MediaPlaylist } from "./parser";
+import type { CueOut, MasterPlaylist, MediaPlaylist } from "./parser";
 import type { Session } from "./session";
 import type { Interstitial } from "./types";
 import type { VmapAdBreak } from "./vmap";
@@ -70,6 +72,8 @@ export async function formatMediaPlaylist(
 
   rewriteMediaPlaylistUrls(media, mediaUrl);
 
+  rewriteCues(media);
+
   return stringifyMediaPlaylist(media);
 }
 
@@ -190,6 +194,33 @@ export function rewriteMediaPlaylistUrls(
   });
 }
 
+function rewriteCues(media: MediaPlaylist) {
+  const cuesMap: {
+    dateTime: DateTime;
+    cueOut: CueOut;
+  }[] = [];
+
+  for (const segment of media.segments) {
+    if (segment.cueIn) {
+      delete segment.cueIn;
+      segment.discontinuity = true;
+    }
+    if (segment.cueOut) {
+      if (!segment.programDateTime) {
+        throw new Error("No PDT");
+      }
+      cuesMap.push({
+        dateTime: segment.programDateTime,
+        cueOut: segment.cueOut,
+      });
+      delete segment.cueOut;
+      segment.discontinuity = true;
+    }
+  }
+
+  insertInterstitialsFromCuesMap(cuesMap, media);
+}
+
 async function initSessionOnMasterReq(session: Session) {
   let storeSession = false;
 
@@ -242,3 +273,19 @@ export function mapAdBreaksToSessionInterstitials(
 
   return interstitials;
 }
+
+export async function formatLiveAssetList() {
+  const randNumber = Math.trunc(Math.random() * 100_000);
+  const assets = await getAssetsFromVast({
+    url: `https://pubads.g.doubleclick.net/gampad/ads?iu=/21775744923/external/single_ad_samples&sz=640x480&cust_params=sample_ct%3Dlinear&ciu_szs=300x250%2C728x90&gdfp_req=1&output=vast&unviewed_position_start=1&env=vp&impl=s&correlator=${randNumber}`,
+  });
+
+  return {
+    ASSETS: assets.map((asset) => {
+      return {
+        URI: asset.url,
+        DURATION: asset.duration,
+      };
+    }),
+  };
+}

packages/stitcher/src/routes/session.ts

@@ -5,6 +5,7 @@ import { decrypt } from "../lib/crypto";
 import {
   createMasterUrl,
   formatAssetList,
+  formatLiveAssetList,
   formatMasterPlaylist,
   formatMediaPlaylist,
 } from "../playlist";
@@ -181,6 +182,12 @@ export const sessionRoutes = new Elysia()
     "/out/asset-list.json",
     async ({ query }) => {
       const sessionId = query.sid;
+
+      // TODO: THIS IS A BAD IDEA
+      if (sessionId === "live") {
+        return await formatLiveAssetList();
+      }
+
       const dateTime = DateTime.fromISO(query.dt);
 
       const session = await getSession(sessionId);