/**
 * Computes months of runway from cash, reserves, and burn rate
 * Formula: (cash + savings) ÷ average monthly burn in scenario
 */
export const useRunway = () => {
  const calculateRunway = (cash: number, savings: number, monthlyBurn: number): number => {
    if (monthlyBurn <= 0) return Infinity
    return (cash + savings) / monthlyBurn
  }
  
  const getRunwayStatus = (months: number): 'green' | 'yellow' | 'red' => {
    if (months >= 3) return 'green'
    if (months >= 2) return 'yellow'
    return 'red'
  }
  
  const formatRunway = (months: number): string => {
    if (months === Infinity) return '∞ months'
    return `${months.toFixed(1)} months`
  }
  
  return {
    calculateRunway,
    getRunwayStatus,
    formatRunway
  }
}