refactor: sheetinfo

src/main.ts

@@ -6,7 +6,7 @@ import { downloadMscz } from './mscz'
 import { getFileUrl } from './file'
 import { WebMscore, loadSoundFont } from './mscore'
 import { BtnList, BtnAction, BtnListMode } from './btn'
-import { ScoreInfoInPage } from './scoreinfo'
+import { ScoreInfoInPage, SheetInfoInPage } from './scoreinfo'
 import i18n from './i18n'
 
 const main = (): void => {
@@ -27,7 +27,7 @@ const main = (): void => {
 
   btnList.add({
     name: i18n('DOWNLOAD')('PDF'),
-    action: BtnAction.process(() => downloadPDF(scoreinfo), fallback, 3 * 60 * 1000 /* 3min */),
+    action: BtnAction.process(() => downloadPDF(scoreinfo, new SheetInfoInPage(document)), fallback, 3 * 60 * 1000 /* 3min */),
   })
 
   btnList.add({

src/pdf.ts

@@ -2,7 +2,7 @@
 import { PDFWorkerHelper } from './worker-helper'
 import { getFileUrl } from './file'
 import { saveAs } from './utils'
-import { ScoreInfo } from './scoreinfo'
+import { ScoreInfo, SheetInfo } from './scoreinfo'
 
 let pdfBlob: Blob
 
@@ -23,13 +23,13 @@ const _downloadPDF = async (imgURLs: string[], imgType: 'svg' | 'png', name = ''
   saveAs(pdfBlob, `${name}.pdf`)
 }
 
-export const downloadPDF = async (scoreinfo: ScoreInfo): Promise<void> => {
-  const imgType = scoreinfo.sheetImgType
-  const pageCount = scoreinfo.pageCount
+export const downloadPDF = async (scoreinfo: ScoreInfo, sheet: SheetInfo): Promise<void> => {
+  const imgType = sheet.imgType
+  const pageCount = sheet.pageCount
 
   const rs = Array.from({ length: pageCount }).map((_, i) => {
     if (i === 0) { // The url to the first page is static. We don't need to use API to obtain it.
-      return scoreinfo.thumbnailUrl
+      return sheet.thumbnailUrl
     } else { // obtain image urls using the API
       return getFileUrl(scoreinfo.id, 'img', i)
     }

src/scoreinfo.ts

@@ -7,9 +7,6 @@ export abstract class ScoreInfo {
   abstract id: number;
   abstract title: string;
 
-  abstract pageCount: number;
-  abstract thumbnailUrl: string;
-
   public store = new Map<symbol, any>();
 
   get idLastDigit (): number {
@@ -27,12 +24,6 @@ export abstract class ScoreInfo {
   get msczCidUrl (): string {
     return `https://ipfs.infura.io:5001/api/v0/block/stat?arg=${this.msczIpfsRef}`
   }
-
-  get sheetImgType (): 'svg' | 'png' {
-    const thumbnail = this.thumbnailUrl
-    const imgtype = thumbnail.match(/\.(\w+)$/)![1]
-    return imgtype as 'svg' | 'png'
-  }
 }
 
 export class ScoreInfoInPage extends ScoreInfo {
@@ -48,6 +39,21 @@ export class ScoreInfoInPage extends ScoreInfo {
     const el = this.document.querySelector("meta[property='og:title']") as HTMLMetaElement
     return el.content
   }
+}
+
+export abstract class SheetInfo {
+  abstract pageCount: number;
+  abstract thumbnailUrl: string;
+
+  get imgType (): 'svg' | 'png' {
+    const thumbnail = this.thumbnailUrl
+    const imgtype = thumbnail.match(/\.(\w+)$/)![1]
+    return imgtype as 'svg' | 'png'
+  }
+}
+
+export class SheetInfoInPage extends SheetInfo {
+  constructor (private document: Document) { super() }
 
   get pageCount (): number {
     return this.document.querySelectorAll('.gXB83').length