jamp3/src/lib/common/pretty-json.ts

mp3, id3v1, id3v2 - reader & writer

function quoteJSONProperty(str: any): string {
	if (typeof str !== 'string') {
		str = str.toString();
	}
	return str.match(/^".*"$/) ? str : '"' + str.replace(/"/g, '\\"') + '"';
}

function objToString(obj: any, level: number, options: { flatNodes: Array<string>; space: string }): string {
	const lines: Array<string> = [];
	Object.keys(obj).forEach(prop => {
		const val = obj[prop];
		if (val !== undefined) {
			const str = quoteJSONProperty(prop) + ': ' + prettyJSONify(val, level + 1, options.flatNodes.indexOf(prop) >= 0, options);
			lines.push(options.space.repeat(level + 1) + str);
		}
	});
	return (lines.length === 0) ? '{}' : '{\n' + lines.join(',\n') + '\n' + options.space.repeat(level) + '}';
}

function arrayToString(obj: Array<any>, level: number, options: { flatNodes: Array<string>; space: string }): string {
	const lines: Array<string> = [];
	obj.forEach((c: any) => {
		lines.push(options.space.repeat(level + 1) + prettyJSONify(c, level + 1, false, options));
	});
	if (lines.length === 0) {
		return '[]';
	}
	return '[\n' + lines.join(',\n') + '\n' + options.space.repeat(level) + ']';
}

export function prettyJSONify(obj: any, level: number, flat: boolean, options: { flatNodes: Array<string>; space: string }): string {
	if (flat || obj instanceof Buffer) {
		return JSON.stringify(obj);
	}
	if (obj instanceof Array) {
		return arrayToString(obj, level, options);
	}
	if (typeof obj !== 'object') {
		return JSON.stringify(obj, null, options.space);
	}
	return objToString(obj, level, options);
}

export function toPrettyJsonWithBin(o: any): string {
	return prettyJSONify(o, 0, false, {flatNodes: ['head'], space: ' '});
}