import { youtube_v3 } from "googleapis";
import type { ChannelCache } from "../../types/niche.types.js";
export declare const STALENESS_DAYS_NEW = 14;
export declare const STALENESS_DAYS_ESTABLISHED = 45;
export declare const MIN_AVG_VIEWS_THRESHOLD = 1000;
export declare const MAX_SUBSCRIBER_CAP = 100000;
export declare const MIN_SUBSCRIBER_THRESHOLD = 1000;
export declare const MIN_OUTLIER_VIEW_COUNT = 1000;
export declare const MIN_VIDEO_DURATION_SECONDS = 180;
export declare function isQuotaError(error: unknown): boolean;
export declare function calculateChannelAgePublishedAfter(channelAge: "NEW" | "ESTABLISHED"): string;
export declare function getOutlierMultiplier(outlierMagnitude: "STANDARD" | "STRONG"): number;
export declare function getConsistencyThreshold(consistencyLevel: "MODERATE" | "HIGH"): number;
export declare function applyStalnessHeuristic(channel: ChannelCache, channelAge: "NEW" | "ESTABLISHED"): boolean;
export declare function calculateDerivedMetrics(channel: ChannelCache): {
    historicalAvgViewsPerVideo: number;
    libraryEngagementRatio: number;
};
export declare function calculateChannelAge(createdAt: Date): number;
export declare function isValidChannelAge(ageInMonths: number, channelAge: "NEW" | "ESTABLISHED"): boolean;
export declare function shouldSkipReAnalysis(channelData: ChannelCache): boolean;
/**
 * Parses an ISO 8601 duration string (e.g., "PT1M30S") into total seconds.
 * Handles hours, minutes, and seconds.
 * @param duration The ISO 8601 duration string.
 * @returns The total duration in seconds.
 */
export declare function parseISO8601Duration(duration: string): number;
export declare function calculateConsistencyMetrics(videos: youtube_v3.Schema$Video[], subscriberCount: number): {
    sourceVideoCount: number;
    metrics: {
        STANDARD: {
            outlierVideoCount: number;
            consistencyPercentage: number;
        };
        STRONG: {
            outlierVideoCount: number;
            consistencyPercentage: number;
        };
    };
};