import { stripVTControlCharacters } from "node:util";
import type {
	ExtensionStatusColorMode,
	ExtensionStatusPlacement,
	PolishedTuiConfig,
} from "./config";
import { getExtensionStatusColorMode, getExtensionStatusPlacement } from "./config";

export type ExtensionStatusSegment = {
	key: string;
	text: string;
	placement: ExtensionStatusPlacement;
	colorMode: ExtensionStatusColorMode;
};

export type ExtensionStatusSegmentsByPlacement = {
	left: ExtensionStatusSegment[];
	middle: ExtensionStatusSegment[];
	right: ExtensionStatusSegment[];
};

const safeSgrPattern = /\x1b\[[0-9;:]*m/g;
const sgrPlaceholderPattern = /__ZENTUI_SGR_(\d+)__/g;

function compareKeys(a: ExtensionStatusSegment, b: ExtensionStatusSegment): number {
	return a.key < b.key ? -1 : a.key > b.key ? 1 : 0;
}

function normalizeStatusWhitespace(value: string): string {
	return value
		.replace(/[\r\n\t\f\v]+/g, " ")
		.replace(/[\u0000-\u001f\u007f-\u009f]/g, "")
		.replace(/\s+/g, " ")
		.trim();
}

export function sanitizeExtensionStatusText(value: string): string {
	return normalizeStatusWhitespace(stripVTControlCharacters(value));
}

function hasVisibleStatusText(value: string): boolean {
	return sanitizeExtensionStatusText(value).length > 0;
}

export function sanitizeExtensionStatusOriginalText(value: string): string {
	const safeSequences: string[] = [];
	const protectedValue = value.replace(safeSgrPattern, (sequence) => {
		const index = safeSequences.push(sequence) - 1;
		return `__ZENTUI_SGR_${index}__`;
	});
	const cleaned = normalizeStatusWhitespace(stripVTControlCharacters(protectedValue));
	const restored = cleaned.replace(sgrPlaceholderPattern, (_match, indexText: string) => {
		const index = Number.parseInt(indexText, 10);
		return safeSequences[index] ?? "";
	});

	return hasVisibleStatusText(restored) ? restored : "";
}

export function collectExtensionStatusSegments(
	statuses: ReadonlyMap<string, string>,
	config: PolishedTuiConfig,
): ExtensionStatusSegmentsByPlacement {
	const segments: ExtensionStatusSegmentsByPlacement = {
		left: [],
		middle: [],
		right: [],
	};

	for (const [key, value] of statuses.entries()) {
		const placement = getExtensionStatusPlacement(config, key);
		if (placement === "off") continue;

		const colorMode = getExtensionStatusColorMode(config, key);
		const text =
			colorMode === "original"
				? sanitizeExtensionStatusOriginalText(value)
				: sanitizeExtensionStatusText(value);
		if (!text) continue;

		segments[placement].push({ key, text, placement, colorMode });
	}

	segments.left.sort(compareKeys);
	segments.middle.sort(compareKeys);
	segments.right.sort(compareKeys);
	return segments;
}