/** @file Http text-decode module. */
export function decodeText(buffer: Buffer, contentType: string | undefined): string {
	const charset = contentType
		?.match(/charset=([^;]+)/iu)?.[1]
		?.trim()
		.toLowerCase()
		.replaceAll("_", "-");
	if (charset === "ascii") {
		return buffer.toString("ascii");
	}
	if (charset === "latin1" || charset === "latin-1" || charset === "iso-8859-1") {
		return buffer.toString("latin1");
	}
	if (charset === "windows-1252" || charset === "cp1252") {
		return decodeWindows1252(buffer);
	}
	return buffer.toString("utf8");
}

const WINDOWS_1252_CONTROLS: Record<number, string> = {
	0x80: "€",
	0x82: "‚",
	0x83: "ƒ",
	0x84: "„",
	0x85: "…",
	0x86: "†",
	0x87: "‡",
	0x88: "ˆ",
	0x89: "‰",
	0x8a: "Š",
	0x8b: "‹",
	0x8c: "Œ",
	0x8e: "Ž",
	0x91: "‘",
	0x92: "’",
	0x93: "“",
	0x94: "”",
	0x95: "•",
	0x96: "–",
	0x97: "—",
	0x98: "˜",
	0x99: "™",
	0x9a: "š",
	0x9b: "›",
	0x9c: "œ",
	0x9e: "ž",
	0x9f: "Ÿ",
};

function decodeWindows1252(buffer: Buffer): string {
	let text = "";
	for (const byte of buffer) {
		text += WINDOWS_1252_CONTROLS[byte] ?? String.fromCodePoint(byte);
	}
	return text;
}