From f285f4e4bd6e2517dbdcf055c18595752bfc72ce Mon Sep 17 00:00:00 2001
From: JimmyLv <jimmy.jinglv@gmail.com>
Date: Wed, 8 Mar 2023 16:28:48 +0800
Subject: [PATCH] feat: improve youtube and bilibili subtitles

---
 lib/bilibili/fetchBilibiliSubtitle.ts | 18 ++---------
 middleware.ts                         |  9 ++++--
 utils/reduceSubtitleTimestamp.ts      | 44 ++++++++++++++++++++++++++-
 3 files changed, 52 insertions(+), 19 deletions(-)

diff --git a/lib/bilibili/fetchBilibiliSubtitle.ts b/lib/bilibili/fetchBilibiliSubtitle.ts
index 4fe3d47a..407736b2 100644
--- a/lib/bilibili/fetchBilibiliSubtitle.ts
+++ b/lib/bilibili/fetchBilibiliSubtitle.ts
@@ -1,4 +1,5 @@
 import { fetchBilibiliSubtitleUrls } from "~/lib/bilibili/fetchBilibiliSubtitleUrls";
+import { reduceBilibiliSubtitleTimestamp } from "~/utils/reduceSubtitleTimestamp";
 
 export async function fetchBilibiliSubtitle(videoId: string) {
   // const res = await pRetry(async () => await fetchBilibiliSubtitles(videoId), {
@@ -26,21 +27,6 @@ export async function fetchBilibiliSubtitle(videoId: string) {
 
   const subtitleResponse = await fetch(subtitleUrl);
   const subtitles = await subtitleResponse.json();
-  /*{
-      "from": 16.669,
-      "to": 18.619,
-      "sid": 8,
-      "location": 2,
-      "content": "让ppt变得更加精彩",
-      "music": 0.0
-    },*/
-  const transcripts = subtitles?.body.map(
-    (item: { from: number; content: string }, index: number) => {
-      return {
-        text: `${item.from}: ${item.content}`,
-        index
-      };
-    }
-  );
+  const transcripts = reduceBilibiliSubtitleTimestamp(subtitles?.body);
   return { title, subtitlesArray: transcripts, descriptionText };
 }
diff --git a/middleware.ts b/middleware.ts
index e3480995..97eb8025 100644
--- a/middleware.ts
+++ b/middleware.ts
@@ -39,8 +39,13 @@ export async function middleware(req: NextRequest, context: NextFetchEvent) {
       }
     }
 
+    if (isDev) {
+      return NextResponse.next();
+    }
+    //  👇 below only works for production
+
     if (!userKey) {
-      const identifier = req.ip ?? "127.0.0.10";
+      const identifier = req.ip ?? "127.0.0.11";
       const { success, remaining } = await ratelimitForIps.limit(identifier);
       console.log(
         `======== ip ${identifier}, remaining: ${remaining} ========`
@@ -80,7 +85,7 @@ export async function middleware(req: NextRequest, context: NextFetchEvent) {
     }
 
     const result = await redis.get<string>(cacheId);
-    if (!isDev && result) {
+    if (result) {
       console.log("hit cache for ", cacheId);
       return NextResponse.json(result);
     }
diff --git a/utils/reduceSubtitleTimestamp.ts b/utils/reduceSubtitleTimestamp.ts
index 2d806dea..7dc679d5 100644
--- a/utils/reduceSubtitleTimestamp.ts
+++ b/utils/reduceSubtitleTimestamp.ts
@@ -1,9 +1,11 @@
 import { CommonSubtitleItem } from "~/lib/types";
 
 export type YoutubeSubtitleItem = { start: number; lines: string[] };
+/*{ "from": 16.669, "content": "让ppt变得更加精彩" },*/
+export type BilibiliSubtitleItem = { from: number; content: string };
 
 export function reduceSubtitleTimestamp(
-  subtitles: Array<YoutubeSubtitleItem>
+  subtitles: Array<YoutubeSubtitleItem> = []
 ): Array<CommonSubtitleItem> {
   // 把字幕数组总共分成 20 组
   const TOTAL_GROUP_COUNT = 20;
@@ -42,3 +44,43 @@ export function reduceSubtitleTimestamp(
     []
   );
 }
+export function reduceBilibiliSubtitleTimestamp(
+  subtitles: Array<BilibiliSubtitleItem> = []
+): Array<CommonSubtitleItem> {
+  // 把字幕数组总共分成 20 组
+  const TOTAL_GROUP_COUNT = 20;
+  // 如果字幕不够多，就每三组合并一下
+  const MINIMUM_COUNT_ONE_GROUP = 3;
+  const eachGroupCount =
+    subtitles.length > TOTAL_GROUP_COUNT
+      ? subtitles.length / TOTAL_GROUP_COUNT
+      : MINIMUM_COUNT_ONE_GROUP;
+
+  return subtitles.reduce(
+    (
+      accumulator: CommonSubtitleItem[],
+      current: BilibiliSubtitleItem,
+      index: number
+    ) => {
+      // 计算当前元素在哪一组
+      const groupIndex: number = Math.floor(index / eachGroupCount);
+
+      // 如果是当前组的第一个元素，初始化这一组的字符串
+      if (!accumulator[groupIndex]) {
+        accumulator[groupIndex] = {
+          // 5.88 -> 5.9
+          // text: current.start.toFixed() + ": ",
+          text: current.from + ": ",
+          index: groupIndex,
+        };
+      }
+
+      // 将当前元素添加到当前组的字符串末尾
+      accumulator[groupIndex].text =
+        accumulator[groupIndex].text + current.content + " ";
+
+      return accumulator;
+    },
+    []
+  );
+}