import type { ClassifierContext, ClassifierQuestion, JsonObject, JsonValue } from "@earendil-works/pi-ai";
function record(value: unknown): value is Record<string, unknown> {
	return typeof value === "object" && value !== null && !Array.isArray(value);
}
function json(value: unknown, depth = 0): value is JsonValue {
	if (depth > 64) return false;
	if (value === null || typeof value === "string" || typeof value === "boolean") return true;
	if (typeof value === "number") return Number.isFinite(value);
	if (Array.isArray(value)) return value.every((item) => json(item, depth + 1));
	return record(value) && Object.values(value).every((item) => json(item, depth + 1));
}
function state(value: unknown): value is JsonObject { return record(value) && json(value); }
function strings(value: unknown): value is Record<string, string> {
	return record(value) && Object.values(value).every((item) => typeof item === "string");
}
/** Convert the unchanged public Jev question envelope to upstream's typed classifier context. */
export function toClassifierContext(payload: unknown): ClassifierContext | undefined {
	if (!record(payload) || !state(payload.state) || !record(payload.questions)) return undefined;
	const questions: Record<string, ClassifierQuestion> = {};
	for (const [id, question] of Object.entries(payload.questions)) {
		if (!record(question)) return undefined;
		const raw = question.instructions;
		const instructions = typeof raw === "string" ? raw : record(raw) && typeof raw.question === "string"
			? raw.question + (typeof raw.focus === "string" ? `\nFocus: ${raw.focus}` : "") : undefined;
		if (instructions === undefined) return undefined;
		if (question.type === "choice" && strings(question.criteria)) {
			questions[id] = { type: "choice", instructions, criteria: question.criteria };
		} else if (question.type === "score" && Array.isArray(question.criteria) && question.criteria.every((item): item is string => typeof item === "string")) {
			questions[id] = { type: "score", instructions, criteria: question.criteria };
		} else if (question.type === "noul" || question.type === "bool") {
			const criteria = question.criteria;
			const yes = record(criteria) ? criteria.true : undefined;
			const no = record(criteria) ? criteria.false : undefined;
			if (criteria !== undefined && (!strings(criteria) || typeof yes !== "string" || typeof no !== "string")) return undefined;
			questions[id] = { type: "bool", instructions, criteria: typeof yes === "string" && typeof no === "string" ? { true: yes, false: no } : { true: "True", false: "False" } };
		} else return undefined;
	}
	return { state: payload.state, questions };
}
/** Deployed TokenIn accepts string state; preserve typed upstream context via onPayload. */
export function tokenInWirePayload(payload: unknown): unknown {
	if (!record(payload)) throw new Error("TokenIn classifier requires an object payload");
	if (typeof payload.state === "string") return payload;
	if (!state(payload.state)) throw new Error("TokenIn classifier requires JSON state");
	return { ...payload, state: JSON.stringify(payload.state) };
}
export function fitsClassifierRequest(payload: unknown, maxBytes: number): boolean {
	try {
		// Include string-state escaping, not just the smaller in-memory JSON object.
		const wire = record(payload) && "state" in payload ? tokenInWirePayload(payload) : payload;
		const text = JSON.stringify(wire);
		return typeof text === "string" && Number.isFinite(maxBytes) && maxBytes > 0 && Buffer.byteLength(text, "utf8") <= Math.min(maxBytes, 64 * 1024);
	} catch { return false; }
}