export function formatDate(dateStr) {
  if (!dateStr) return ''

  const normalizedDate = toDateInputValue(dateStr)
  const date = new Date(`${normalizedDate}T00:00:00`)

  if (Number.isNaN(date.getTime())) return ''

  return date.toLocaleDateString('en-US', { month: 'short', day: 'numeric', year: 'numeric' })
}

export function toDateInputValue(dateStr) {
  if (!dateStr) return ''
  return String(dateStr).slice(0, 10)
}

export function getExpiryStatus(expiryDate) {
  if (!expiryDate) return { status: 'Unknown', color: '#999', text: '' }

  const today = new Date()
  today.setHours(0, 0, 0, 0)

  const normalizedDate = toDateInputValue(expiryDate)
  const expiry = new Date(`${normalizedDate}T00:00:00`)

  if (Number.isNaN(expiry.getTime())) {
    return { status: 'Unknown', color: '#999', text: '' }
  }

  const daysUntilExpiry = Math.floor((expiry - today) / (1000 * 60 * 60 * 24))

  if (daysUntilExpiry < 0) {
    return { status: 'Expired', color: '#f44336', days: daysUntilExpiry, text: `Expired ${Math.abs(daysUntilExpiry)} days ago` }
  } else if (daysUntilExpiry === 0) {
    return { status: 'Today', color: '#ff9800', days: 0, text: 'Expires today' }
  } else if (daysUntilExpiry <= 7) {
    return { status: 'Soon', color: '#ff9800', days: daysUntilExpiry, text: `Expires in ${daysUntilExpiry} days` }
  } else {
    return { status: 'Fresh', color: '#4CAF50', days: daysUntilExpiry, text: `Expires in ${daysUntilExpiry} days` }
  }
}

export function formatAmount(amount, amountType = '') {
  if (amount == null || amount === '') return 'Amount not set'

  const unit = amountType?.trim() ?? ''
  return unit ? `${amount} ${unit}` : String(amount)
}

export function filterInventoryItems(items, filters = {}) {
  const {
    locationId = '',
    minAmount = 0,
    maxAmount = Infinity,
    minExpiryDate = '',
    maxExpiryDate = '',
  } = filters

  return items.filter(item => {
    const itemLocationId = item.locationId ?? item.location?.id ?? ''
    const locationMatch = !locationId || itemLocationId === locationId

    const numericAmount = item.amount == null ? 0 : Number(item.amount)
    const amountMatch = numericAmount >= minAmount && numericAmount <= maxAmount

    const normalizedExpiryDate = toDateInputValue(item.expiryDate)
    let expiryMatch = true

    if (minExpiryDate && (!normalizedExpiryDate || normalizedExpiryDate < minExpiryDate)) {
      expiryMatch = false
    }

    if (maxExpiryDate && (!normalizedExpiryDate || normalizedExpiryDate > maxExpiryDate)) {
      expiryMatch = false
    }

    return locationMatch && amountMatch && expiryMatch
  })
}