@infinito/id3/src/classes/id3.2.3.frame.js

ID3 Tag Reader/Writer

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

import {StringDecoder} from 'string_decoder';

import id3Tag from './id3tag.js';

export default class id3v2_3Frame {
	constructor(buf,pos) {
		Object.defineProperties(this,{
			FRAME_HEADER_SIZE_BYTES:{
				value:10
			},
			FRAME_ID_SIZE_BYTES:{
				value:4
			},
			FRAME_SIZE_BYTES:{
				value:4
			},
			FRAME_FLAGS_BYTES:{
				value:2
			},
			VALID_FRAMES:{
				value:{
					AENC:"Audio encryption",
					APIC:"Attached picture",
					COMM:"Comments",
					COMR:"Commercial frame",
					ENCR:"Encryption method registration",
					EQUA:"Equalization",
					ETCO:"Event timing codes",
					GEOB:"General encapsulated object",
					GRID:"Group identification registration",
					IPLS:"Involved people list",
					LINK:"Linked information",
					MCDI:"Music CD identifier",
					MLLT:"MPEG location lookup table",
					OWNE:"Ownership frame",
					PRIV:"Private frame",
					PCNT:"Play counter",
					POPM:"Popularimeter",
					POSS:"Position synchronisation frame",
					RBUF:"Recommended buffer size",
					RVAD:"Relative volume adjustment",
					RVRB:"Reverb",
					SYLT:"Synchronized lyric/text",
					SYTC:"Synchronized tempo codes",
					TALB:"Album/Movie/Show title",
					TBPM:"BPM (beats per minute)",
					TCOM:"Composer",
					TCON:"Content type",
					TCOP:"Copyright message",
					TDAT:"Date",
					TDLY:"Playlist delay",
					TENC:"Encoded by",
					TEXT:"Lyricist/Text writer",
					TFLT:"File type",
					TIME:"Time",
					TIT1:"Content group description",
					TIT2:"Title/songname/content description",
					TIT3:"Subtitle/Description refinement",
					TKEY:"Initial key",
					TLAN:"Language(s)",
					TLEN:"Length",
					TMED:"Media type",
					TOAL:"Original album/movie/show title",
					TOFN:"Original filename",
					TOLY:"Original lyricist(s)/text writer(s)",
					TOPE:"Original artist(s)/performer(s)",
					TORY:"Original release year",
					TOWN:"File owner/licensee",
					TPE1:"Lead performer(s)/Soloist(s)",
					TPE2:"Band/orchestra/accompaniment",
					TPE3:"Conductor/performer refinement",
					TPE4:"Interpreted, remixed, or otherwise modified by",
					TPOS:"Part of a set",
					TPUB:"Publisher",
					TRCK:"Track number/Position in set",
					TRDA:"Recording dates",
					TRSN:"Internet radio station name",
					TRSO:"Internet radio station owner",
					TSIZ:"Size",
					TSRC:"ISRC (international standard recording code)",
					TSSE:"Software/Hardware and settings used for encoding",
					TYER:"Year",
					TXXX:"User defined text information frame",
					UFID:"Unique file identifier",
					USER:"Terms of use",
					USLT:"Unsychronized lyric/text transcription",
					WCOM:"Commercial information",
					WCOP:"Copyright/Legal information",
					WOAF:"Official audio file webpage",
					WOAR:"Official artist/performer webpage",
					WOAS:"Official audio source webpage",
					WORS:"Official internet radio station homepage",
					WPAY:"Payment",
					WPUB:"Publishers official webpage",
					WXXX:"User defined URL link frame"
				}
			},
			USED_FRAMES:{
				value:{
					"Album/Movie/Show title":"album",
					"Band/orchestra/accompaniment":"album_artist",
					"Composer":"composer",
					"Content type":"genre",
					"Lead performer(s)/Soloist(s)":"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 flags */
		this.flags = new Uint8Array(buf,pos,this.FRAME_FLAGS_BYTES);
		pos += this.FRAME_FLAGS_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]==0xff)&&(this.data[1]==0xfe)) {
			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])+String.fromCharCode(this.id[3]);
	}
	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:
				var dec = new TextDecoder("utf-8");
				break;
			default:
				throw new Error("Invalid encoding provided");
				return "";
		}
		return dec.decode(this.data).replace(/\0/g,'');
	}
}