refactor: abstract class ScoreInfo

src/scoreinfo.ts

@@ -3,33 +3,59 @@
 const IPNS_KEY = 'QmSdXtvzC8v8iTTZuj5cVmiugnzbR1QATYRcGix4bBsioP'
 const RADIX = 20
 
-export const scoreinfo = {
+export abstract class ScoreInfo {
+  abstract id: number;
+  abstract title: string;
 
-  get id (this: typeof scoreinfo): number {
-    const el = document.querySelector("meta[property='al:ios:url']") as HTMLMetaElement
+  abstract pageCount: number;
+  abstract thumbnailUrl: string;
+  abstract sheetImgType: 'svg' | 'png'
+
+  get idLastDigit (): number {
+    return (+this.id) % RADIX
+  }
+
+  get fileName (): string {
+    return this.title.replace(/[\s<>:{}"/\\|?*~.\0\cA-\cZ]+/g, '_')
+  }
+
+  get msczIpfsRef (): string {
+    return `/ipns/${IPNS_KEY}/${this.idLastDigit}/${this.id}.mscz`
+  }
+
+  get msczCidUrl (): string {
+    return `https://ipfs.infura.io:5001/api/v0/block/stat?arg=${this.msczIpfsRef}`
+  }
+}
+
+export class ScoreInfoInPage extends ScoreInfo {
+  constructor (private document: Document) { super() }
+
+  get id (): number {
+    const el = this.document.querySelector("meta[property='al:ios:url']") as HTMLMetaElement
     const m = el.content.match(/(\d+)$/) as RegExpMatchArray
     return +m[1]
-  },
+  }
 
-  get title (this: typeof scoreinfo): string {
-    const el = document.querySelector("meta[property='og:title']") as HTMLMetaElement
+  get title (): string {
+    const el = this.document.querySelector("meta[property='og:title']") as HTMLMetaElement
     return el.content
-  },
+  }
 
-  get pageCount (this: typeof scoreinfo): number {
-    return document.querySelectorAll('.gXB83').length
-  },
+  get pageCount (): number {
+    return this.document.querySelectorAll('.gXB83').length
+  }
 
-  get thumbnailUrl (this: typeof scoreinfo): string {
+  get thumbnailUrl (): string {
     // url to the image of the first page
-    const el = document.querySelector("meta[property='og:image']") as HTMLMetaElement
+    const el = this.document.querySelector("meta[property='og:image']") as HTMLMetaElement
     const url = el.content
     return url.split('@')[0]
-  },
+  }
 
   get sheetImgType (): 'svg' | 'png' {
     try {
-      const imgE = document.querySelector('img[src*=score_]') as HTMLImageElement
+      const imgE = this.document.querySelector('img[src*=score_]') as HTMLImageElement
       const { pathname } = new URL(imgE.src)
       // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
       const imgtype = pathname.match(/\.(\w+)$/)![1]
@@ -38,23 +64,9 @@ export const scoreinfo = {
       // return null
       return 'svg'
     }
-  },
-
-  get idLastDigit (this: typeof scoreinfo): number {
-    return (+this.id) % RADIX
-  },
-
-  get fileName (this: typeof scoreinfo): string {
-    return this.title.replace(/[\s<>:{}"/\\|?*~.\0\cA-\cZ]+/g, '_')
-  },
-
-  get msczIpfsRef (this: typeof scoreinfo): string {
-    return `/ipns/${IPNS_KEY}/${this.idLastDigit}/${this.id}.mscz`
-  },
-
-  get msczCidUrl (this: typeof scoreinfo): string {
-    return `https://ipfs.infura.io:5001/api/v0/block/stat?arg=${this.msczIpfsRef}`
-  },
+  }
 }
 
+export const scoreinfo = new ScoreInfoInPage(document)
+
 export default scoreinfo