DESCRIPT.ION support for oputil fb scan

core/descript_ion_file.js

@@ -0,0 +1,66 @@
+/* jslint node: true */
+'use strict';
+
+//	deps
+const fs			= require('graceful-fs');
+const iconv			= require('iconv-lite');
+const async			= require('async');
+
+module.exports = class DescriptIonFile {
+	constructor() {
+		this.entries = new Map();
+	}
+
+	get(fileName) {
+		return this.entries.get(fileName);
+	}
+
+	getDescription(fileName) {
+		const entry = this.get(fileName);
+		if(entry) {
+			return entry.desc;
+		}
+	}
+
+	static createFromFile(path, cb) {
+		fs.readFile(path, (err, descData) => {
+			if(err) {
+				return cb(err);
+			}
+
+			const descIonFile = new DescriptIonFile();
+
+			//	DESCRIPT.ION entries are terminated with a CR and/or LF
+			const lines = iconv.decode(descData, 'cp437').split(/\r?\n/g);
+
+			async.each(lines, (entryData, nextLine) => {
+				//
+				//	We allow quoted (long) filenames or non-quoted filenames.
+				//	FILENAME<SPC>DESC<0x04><program data><CR/LF>
+				//
+				const parts = entryData.match(/^(?:(?:"([^"]+)" )|(?:([^ ]+) ))([^\x04]+)\x04(.)[^\r\n]*$/);	//	eslint-disable-line no-control-regex
+				if(!parts) {
+					return nextLine(null);
+				}
+
+				const fileName	= parts[1] || parts[2];
+				const desc		= parts[3].replace(/\\r\\n|\\n/g, '\r\n');	//	un-escape CR/LF's
+
+				descIonFile.entries.set(
+					fileName,
+					{
+						desc		: desc,
+						programId	: parts[4],
+						programData	: parts[5],
+					}
+				);
+
+				return nextLine(null);
+			},
+			() => {
+				return cb(null, descIonFile);
+			});
+		});
+	}
+};
+