import type { ExtensionContext, SessionEntry } from "@earendil-works/pi-coding-agent";

export interface ContextFamilyBindingOptions {
	/** Caller asserts entries through this boundary were inherited by a new native fork, before child work. */
	fork?: { lastInheritedEntryId: string };
}

/** Classify only child-owned startup records, without modifying inherited history. */
export function bindingStartupEntries(ctx: ExtensionContext, options?: ContextFamilyBindingOptions): SessionEntry[] {
	const entries = ctx.sessionManager.getEntries();
	if (!options?.fork) return entries;
	const id = options.fork.lastInheritedEntryId;
	const boundary = entries.findIndex(entry => entry.id === id);
	if (!ctx.sessionManager.getHeader()?.parentSession || typeof id !== "string" || !id || boundary < 0)
		throw new Error("Fork family binding requires an inherited entry boundary in a new native fork");
	return entries.slice(boundary + 1);
}

export function hasConversation(entries: readonly SessionEntry[]): boolean {
	return entries.some(entry => entry.type === "message" || entry.type === "custom_message" ||
		entry.type === "compaction" || entry.type === "branch_summary");
}