import type { ExtensionContext } from "@earendil-works/pi-coding-agent";
import { isRecord } from "../../fs.ts";
import { resolveOAuthAccess } from "../auth.ts";
import { sanitizeQuotaError } from "../sanitize.ts";
import type { QuotaSnapshot, QuotaWindow } from "../types.ts";

export const SUPERGROK_BILLING_URL = "https://cli-chat-proxy.grok.com/v1/billing?format=credits";

function firstIso(...values: unknown[]): string | undefined {
	for (const value of values) {
		if (typeof value !== "string") continue;
		const date = new Date(value);
		if (!Number.isNaN(date.getTime())) return date.toISOString();
	}
	return undefined;
}

export function parseSuperGrokBilling(payload: unknown, fetchedAt: number): QuotaSnapshot {
	if (!isRecord(payload) || !isRecord(payload.config)) {
		return { provider: "supergrok", title: "SuperGrok", windows: [], fetchedAt, ok: false, error: "unexpected response" };
	}
	const config = payload.config;
	const period = isRecord(config.currentPeriod) ? config.currentPeriod : undefined;
	const usedPercent = typeof config.creditUsagePercent === "number" && Number.isFinite(config.creditUsagePercent)
		? config.creditUsagePercent
		: 0;
	const resetsAt = firstIso(
		period?.end,
		period?.endTime,
		period?.endsAt,
		config.billingPeriodEnd,
	);
	const primary: QuotaWindow = {
		id: "weekly",
		label: "Weekly credits",
		usedPercent,
		...(resetsAt ? { resetsAt } : {}),
	};
	return {
		provider: "supergrok",
		title: "SuperGrok",
		primary,
		windows: [primary],
		fetchedAt,
		ok: true,
	};
}

export async function fetchSuperGrokQuota(
	ctx: Pick<ExtensionContext, "modelRegistry">,
	fetchedAt = Date.now(),
	fetchImpl: typeof fetch = fetch,
): Promise<QuotaSnapshot> {
	const auth = await resolveOAuthAccess(ctx, "xai");
	if (!auth.ok) {
		return { provider: "supergrok", title: "SuperGrok", windows: [], fetchedAt, ok: false, error: auth.error };
	}
	try {
		const response = await fetchImpl(SUPERGROK_BILLING_URL, {
			headers: {
				Authorization: `Bearer ${auth.access.accessToken}`,
				Accept: "application/json",
			},
		});
		if (!response.ok) {
			return { provider: "supergrok", title: "SuperGrok", windows: [], fetchedAt, ok: false, error: `HTTP ${response.status}` };
		}
		return parseSuperGrokBilling(await response.json(), fetchedAt);
	} catch (error) {
		return { provider: "supergrok", title: "SuperGrok", windows: [], fetchedAt, ok: false, error: sanitizeQuotaError(error) };
	}
}