/**
 * Credible source metadata for an MCP adapter extension. Only the paths a tool
 * actually comes from count: descriptions, labels and parameter schemas are
 * written by the tool author and must not classify a tool as MCP.
 */
const MCP_SOURCE_INFO_PATTERN = /(?:^|[/\\])(?:pi-)?mcp(?:-adapter)?(?:[/\\]|$)/i;

export function isRecord(value: unknown): value is Record<string, unknown> {
	return typeof value === "object" && value !== null && !Array.isArray(value);
}

export function toRecord(value: unknown): Record<string, unknown> {
	if (!isRecord(value)) {
		return {};
	}

	return value;
}

export function getTextField(value: unknown, field: string): string | undefined {
	const record = toRecord(value);
	const raw = record[field];
	return typeof raw === "string" && raw.trim().length > 0 ? raw.trim() : undefined;
}

/** Native MCP tools are named `mcp__<server>__<tool>`; history renders before a server connects. */
export function isNativeMcpToolName(name: unknown): boolean {
	return typeof name === "string" && name.startsWith("mcp__");
}

/** True when a tool's source metadata names an MCP adapter extension. */
function hasMcpSourceInfo(value: unknown): boolean {
	const sourceInfo = toRecord(value);
	for (const field of ["path", "source", "baseDir"] as const) {
		const raw = sourceInfo[field];
		if (typeof raw === "string" && MCP_SOURCE_INFO_PATTERN.test(raw)) {
			return true;
		}
	}

	return false;
}

export function isMcpToolIdentity(tool: unknown): boolean {
	const record = toRecord(tool);
	return isNativeMcpToolName(record.name) || hasMcpSourceInfo(record.sourceInfo);
}