import { type Activity, type ActivityStatus, type Id, type Milestone, type MilestoneStatus, type Ordered, type Phase, type User } from './types';
import { type DraggableChangeEvent } from './types/utils';
/**
 * Formats minutes into a human-readable time format
 * @param minutes - Time in minutes
 * @param unit - string ('hours' or 'days')
 * @returns Formatted string like "30m", "1h 15m", "4h", "1d 2h", etc.
 */
export declare function formatTimeSpent(minutes: number, unit?: string): string;
/**
 * Gets the unit suffix for display ('h' for hours, 'd' for days)
 * @param unit - string ('hours' or 'days')
 * @returns Unit abbreviation
 */
export declare function getUnitSuffix(unit?: string): string;
export declare function sumPhaseActivitiesAmount(milestones: Milestone[]): number;
export declare function sumTemplateMilestonesAmount(phases: Phase[]): number;
export declare function sumTemplateActivitiesAmount(phases: Phase[]): number;
export declare function getInitialLetters(name: string): string;
export declare function computeNewRank<T extends Ordered>(event: DraggableChangeEvent<T>, list: T[]): string | undefined;
export declare function generateRank<T extends Ordered>(items: T[], index: number): string;
/**
 * Generates a rank for an item at the BEGINNING of a list.
 * Uses genPrev() on the first item to create a rank before it.
 */
export declare function generateRankAtBeginning<T extends Ordered>(items: T[]): string;
/**
 * Generates ranks for multiple items to be appended at the END of a list.
 * Uses genNext() chain starting after the last item.
 * Returns an array of ranks in the order they should be inserted.
 */
export declare function generateRanksAtEnd<T extends Ordered>(items: T[], count: number): string[];
export declare function formatDate(value: string | null | undefined, pattern?: string): string;
export declare function isActivityClosed(activity: Activity, closedStatus: ActivityStatus): boolean;
export declare function isFullyDone(milestone: Milestone, closedStatus: ActivityStatus): boolean;
export declare function milestoneWithStatus(milestone: Milestone, closedStatus: ActivityStatus): Milestone & {
    status: MilestoneStatus;
};
export declare const getUserName: (user: User | undefined | null) => string;
export declare function lightenColor(color: string, alpha?: number): string;
/**
 * Generate a mention name from a user object.
 * Converts "First Last" to "First_Last".
 */
export declare function getMentionName(user: User): string;
/**
 * Extract unique mentioned user IDs from a Markdown/plain-text message.
 */
export declare function extractMentionedUserIds(message: string, users: User[]): Id[];