@infinito/id3/src/classes/id3.2.2.frame.js

ID3 Tag Reader/Writer

import {TextEncoder,TextDecoder} from 'text-encoding';

import id3Tag from './id3tag.js';

export default class id3v2_2Frame {
	constructor(buf,pos) {
		Object.defineProperties(this,{
			FRAME_HEADER_SIZE_BYTES:{
				value:6
			},
			FRAME_ID_SIZE_BYTES:{
				value:3
			},
			FRAME_SIZE_BYTES:{
				value:3
			},
			VALID_FRAMES:{
				value:{
					BUF:"Recommended buffer size",
					CNT:"Play counter",
					COM:"Comments",
					CRA:"Audio encryption",
					CRM:"Encrypted meta frame",
					ETC:"Event timing codes",
					EQU:"Equalization",
					GEO:"General encapsulated object",
					IPL:"Involved people list",
					LNK:"Linked information",
					MCI:"Music CD Identifier",
					MLL:"MPEG location lookup table",
					PIC:"Attached picture",
					POP:"Popularimeter",
					REV:"Reverb",
					RVA:"Relative volume adjustment",
					SLT:"Synchronized lyric/text",
					STC:"Synced tempo codes",
					TAL:"Album/Movie/Show title",
					TBP:"BPM (Beats Per Minute)",
					TCM:"Composer",
					TCO:"Content type",
					TCR:"Copyright message",
					TDA:"Date",
					TDY:"Playlist delay",
					TEN:"Encoded by",
					TFT:"File type",
					TIM:"Time",
					TKE:"Initial key",
					TLA:"Language(s)",
					TLE:"Length",
					TMT:"Media type",
					TOA:"Original artist(s)/performer(s)",
					TOF:"Original filename",
					TOL:"Original Lyricist(s)/text writer(s)",
					TOR:"Original release year",
					TOT:"Original album/Movie/Show title",
					TP1:"Lead artist(s)/Lead performer(s)/Soloist(s)/Performing group",
					TP2:"Band/Orchestra/Accompaniment",
					TP3:"Conductor/Performer refinement",
					TP4:"Interpreted, remixed, or otherwise modified by",
					TPA:"Part of a set",
					TPB:"Publisher",
					TRC:"ISRC (International Standard Recording Code)",
					TRD:"Recording dates",
					TRK:"Track number/Position in set",
					TSI:"Size",
					TSS:"Software/hardware and settings used for encoding",
					TT1:"Content group description",
					TT2:"Title/Songname/Content description",
					TT3:"Subtitle/Description refinement",
					TXT:"Lyricist/text writer",
					TXX:"User defined text information frame",
					TYE:"Year",
					UFI:"Unique file identifier",
					ULT:"Unsychronized lyric/text transcription",
					WAF:"Official audio file webpage",
					WAR:"Official artist/performer webpage",
					WAS:"Official audio source webpage",
					WCM:"Commercial information",
					WCP:"Copyright/Legal information",
					WPB:"Publishers official webpage",
					WXX:"User defined URL link frame"
				}
			},
			USED_FRAMES:{
				value:{
					"Album/Movie/Show title":"album",
					"Band/Orchestra/Accompaniment":"album_artist",
					"Composer":"composer",
					"Content type":"genre",
					"Lead artist(s)/Lead performer(s)/Soloist(s)/Performing group":"artist",
					"Length":"length",
					"Part of a set":"set",
					"Publisher":"publisher",
					"Title/Songname/Content description":"title",
					"Track number/Position in set":"track",
					"Year":"year"
				}
			}		
		});
		if(!(buf instanceof ArrayBuffer)) {
			if(buf=='default') {
				return;
			}
			throw new TypeError(`Invalid buffer passed to ${this.constructor.name}`);
		}
		this.id = new Uint8Array(buf,pos,this.FRAME_ID_SIZE_BYTES);
		if(typeof this.VALID_FRAMES[this.frame()]=="undefined") {
			throw new Error("Invalid frame detected");
		}
		pos += this.FRAME_ID_SIZE_BYTES;
		/* Calculate size */
		this.size = 0;
		var tempbuf = new Uint8Array(buf,pos,this.FRAME_SIZE_BYTES);
		for(var i=0;i<this.FRAME_SIZE_BYTES;i++) {
			this.size<<=8;
			this.size += tempbuf[i];
		}
		pos += this.FRAME_SIZE_BYTES;
		/* Get encoding */
		this.encoding = new Uint8Array(buf,pos,1)[0];
		pos++;
		/* Get data */
		this.data = new Uint8Array(buf,pos,this.size-1);
		/* Remove Unicode BOM (if necessary) */
		/*if((this.data[0]==255)&&(this.data[1]==254)) {
			this.data = new Uint8Array(buf,pos+2,this.size-3);
		}*/
	}
	frame() {
		return String.fromCharCode(this.id[0])+String.fromCharCode(this.id[1])+String.fromCharCode(this.id[2]);
	}
	tag_name() {
		return this.VALID_FRAMES[this.frame()];
	}
	add_to_ID3(tags_obj) {
		var tag_toset = this.USED_FRAMES[this.tag_name()];
		if(typeof tag_toset=="undefined") {
			return false;
		}
		if(!(tags_obj instanceof id3Tag)) {
			throw new Error("Passed object invalid");
			return false;
		}
		tags_obj[tag_toset] = this.content();
		return true;
	}
	content() {
		if(!(this.data instanceof Uint8Array)) {
			return "";
		}
		if(this.data.size==0) {
			return "";
		}
		switch(this.encoding) {
			case 0:
				var dec = new TextDecoder("windows-1252");
				break;
			case 1:
				throw new Error("Not implemented");
				return "";
				//Should be unicode
				//var dec = new TextDecoder("utf-8");
			default:
				throw new Error("Invalid encoding provided");
				return "";
		}
		return dec.decode(this.data).replace(/\0/g,'');
	}
}