import { homedir } from "node:os";
import { isAbsolute, join, relative, resolve } from "node:path";

const WINDOWS_DRIVE_RE = /^[a-zA-Z]:[\\/]/;
const HOME_PATH_RE = /^~(?:[\\/]|$)/;

export function resolveWorkspacePath(cwd: string, inputPath: string): string {
	const normalized = normalizeExternalPath(inputPath);
	return isAbsolute(normalized) || WINDOWS_DRIVE_RE.test(normalized) ? resolve(normalized) : resolve(cwd, normalized);
}

export function isExternalAbsolutePath(inputPath: string): boolean {
	const normalized = normalizeExternalPath(inputPath);
	return HOME_PATH_RE.test(inputPath.trim()) || isAbsolute(normalized) || WINDOWS_DRIVE_RE.test(normalized);
}

export function isPathInsideWorkspace(cwd: string, inputPath: string): boolean {
	const workspace = resolve(cwd);
	const target = resolveWorkspacePath(cwd, inputPath);
	const rel = relative(workspace, target);
	return rel === "" || (!rel.startsWith("..") && !isAbsolute(rel));
}

export function workspacePathBlockReason(cwd: string, inputPath: string, action = "访问"): string | undefined {
	if (isPathInsideWorkspace(cwd, inputPath)) return undefined;
	return `拒绝${action}工作区外路径 ${inputPath}。执行指令：改用当前业务项目内的相对路径；确需处理外部文件时，先复制到当前工作区并确认不会泄露凭证、Token、连接串或个人文件。`;
}

export function normalizeExternalPath(inputPath: string): string {
	let value = inputPath.trim();
	if (HOME_PATH_RE.test(value)) {
		const rest = value.slice(1).replace(/^[\\/]/, "");
		value = rest ? join(homedir(), rest) : homedir();
	}

	if (value.startsWith("file://")) {
		try {
			value = new URL(value).pathname;
		} catch {
			// Keep original value when it is not a valid file URL.
		}
	}

	if (process.platform === "win32") {
		const wsl = value.match(/^\/mnt\/([a-zA-Z])\/(.*)$/);
		if (wsl) return `${wsl[1].toUpperCase()}:\\${wsl[2].replace(/\//g, "\\")}`;

		const msys = value.match(/^\/([a-zA-Z])\/(.*)$/);
		if (msys) return `${msys[1].toUpperCase()}:\\${msys[2].replace(/\//g, "\\")}`;
	}

	return value;
}

export function hasUnixDrivePath(inputPath: string): boolean {
	return /^\/mnt\/[a-zA-Z]\//.test(inputPath.trim()) || /^\/[a-zA-Z]\//.test(inputPath.trim());
}

export function windowsPathHint(inputPath: string): string | undefined {
	if (process.platform !== "win32" || !hasUnixDrivePath(inputPath)) return undefined;
	return normalizeExternalPath(inputPath);
}

const SOURCE_EXTENSIONS = new Set([
	".java",
	".kt",
	".kts",
	".xml",
	".properties",
	".yml",
	".yaml",
	".sql",
	".ksql",
	".cs",
	".py",
]);

/**
 * 判断路径是否指向源码文件（Java/Kotlin/XML/SQL/C#/Python 等）。
 *
 * 迁移说明：此函数原位于 harness/path-policy.ts，随 V2 重构迁移至 platform/path.ts，
 * 作为平台级路径工具的一部分，供 tool-gateway 和 delegation 模块共同使用。
 */
export function isSourceLikePath(path: string): boolean {
	const normalized = normalizeRelativePath(path);
	const lastSegment = normalized.split("/").at(-1) ?? normalized;
	const dotIndex = lastSegment.lastIndexOf(".");
	if (dotIndex < 0) return false;
	return SOURCE_EXTENSIONS.has(lastSegment.slice(dotIndex).toLowerCase());
}

function normalizeRelativePath(path: string): string {
	return path.replace(/\\/g, "/").replace(/^\.\//, "").replace(/^\/+/, "");
}