import type { PickerCapability, PickerExcluded, PickerNode } from '../../types/filePicker'

export function normalizePickerFormat(format: string): string {
  return format.trim().replace(/^\./, '').toLowerCase()
}

export function pickerExclusion(
  node: PickerNode,
  capability?: PickerCapability,
  skipBlanks = false,
): PickerExcluded | null {
  const base = { path: node.path, name: node.name }
  if (node.unavailableReason) return { ...base, reason: 'unreadable' }
  if (skipBlanks && capability?.isBlank?.(node)) return { ...base, reason: 'blank' }
  if (node.kind === 'folder') return null
  const formats = capability?.formats.map(normalizePickerFormat) ?? []
  if (formats.length && !formats.some((format) => node.name.toLowerCase().endsWith(`.${format}`))) {
    return { ...base, reason: 'unsupported' }
  }
  if (capability?.maxBytes != null && node.bytes != null && node.bytes > capability.maxBytes) {
    return { ...base, reason: 'tooLarge' }
  }
  return null
}

export function pickerReason(excluded: PickerExcluded | null, node?: PickerNode): string {
  if (!excluded) return ''
  return {
    unsupported: 'This format is not supported by this source.',
    tooLarge: 'This file exceeds the size limit for this source.',
    blank: 'Skipped by the blank-file rule.',
    unreadable: node?.unavailableReason || 'This item cannot be read.',
    deselected: 'Removed from the selection.',
    forbidden: 'This item is not permitted by the system filter.',
  }[excluded.reason]
}

export function pickerFormat(name: string): string {
  const compound = /\.(mzml|mzxml)\.gz$/i.exec(name)
  return compound ? `${compound[1]}.gz` : name.includes('.') ? name.split('.').pop()! : ''
}