export type AlertA11yProps = {
  role: 'alert';
  'aria-live': 'assertive' | 'polite';
  'aria-label': string;
};

export function alertLabel(level: string, description: string): AlertA11yProps {
  return {
    role: 'alert',
    'aria-live': level === 'danger' ? 'assertive' : 'polite',
    'aria-label': description,
  };
}

export type ProgressbarA11yProps = {
  role: 'progressbar';
  'aria-label': string;
  'aria-valuenow': number;
  'aria-valuemin': number;
  'aria-valuemax': number;
  'aria-valuetext': string;
};

export function progressLabel(
  label: string,
  valuePct: number,
  description: string,
): ProgressbarA11yProps {
  return {
    role: 'progressbar',
    'aria-label': label,
    'aria-valuenow': valuePct,
    'aria-valuemin': 0,
    'aria-valuemax': 100,
    'aria-valuetext': description,
  };
}

export type AriaLabelOnly = { 'aria-label': string };

export function streakLabel(days: number): AriaLabelOnly {
  return { 'aria-label': `${days} day streak` };
}

export type ButtonA11yProps = {
  'aria-label': string;
  'aria-roledescription'?: string;
};

export function buttonLabel(text: string, hint?: string): ButtonA11yProps {
  return {
    'aria-label': text,
    ...(hint ? { 'aria-roledescription': hint } : {}),
  };
}

export function achievementLabel(name: string, description: string): AriaLabelOnly {
  return { 'aria-label': `Achievement: ${name} — ${description}` };
}

export type TimerA11yProps = {
  'aria-label': string;
  'aria-live': 'polite';
};

export function timerLabel(
  hours: number,
  minutes: number,
  seconds: number,
  status: string,
): TimerA11yProps {
  return {
    'aria-label': `Timer: ${hours}h ${minutes}m ${seconds}s, ${status}`,
    'aria-live': 'polite',
  };
}

export type SliderA11yProps = {
  role: 'slider';
  'aria-label': string;
  'aria-valuenow': number;
  'aria-valuemin': number;
  'aria-valuemax': number;
};

export function sliderLabel(
  label: string,
  value: number,
  min: number,
  max: number,
): SliderA11yProps {
  return {
    role: 'slider',
    'aria-label': label,
    'aria-valuenow': value,
    'aria-valuemin': min,
    'aria-valuemax': max,
  };
}

function plural(n: number, singular: string, pluralForm: string): string {
  const word = n === 1 ? singular : pluralForm;
  return `${n} ${word}`;
}

/**
 * Spoken-friendly duration from a fractional hour value, e.g. 12 → "12 hours", 1.5 → "1 hour 30 minutes".
 */
export function formatDurationForA11y(hours: number): string {
  const totalMinutes = Math.round(hours * 60);
  const h = Math.floor(totalMinutes / 60);
  const m = totalMinutes % 60;

  if (h === 0 && m === 0) {
    return '0 minutes';
  }
  if (m === 0) {
    return plural(h, 'hour', 'hours');
  }
  if (h === 0) {
    return plural(m, 'minute', 'minutes');
  }
  return `${plural(h, 'hour', 'hours')} ${plural(m, 'minute', 'minutes')}`;
}