import { posix } from 'node:path'

const htmlExtension = '.html'

export function ensureLeadingSlash(path: string): string {
  return path.startsWith('/') ? path : `/${path}`
}

export function ensureTrailingSlash(path: string): string {
  return path.endsWith('/') ? path : `${path}/`
}

export function stripLeadingSlash(path: string) {
  return path.replace(/^\//, '')
}

export function stripTrailingSlash(path: string) {
  return path.replace(/\/$/, '')
}

export function pathnameToSlug(pathname: string): string {
  const base = stripTrailingSlash(import.meta.env.BASE_URL)

  if (pathname.startsWith(base)) {
    pathname = pathname.replace(base, '')
  }

  const segments = pathname.split('/')

  if (segments.at(-1) === 'index.html') {
    segments.pop()
  } else if (segments.at(-1)?.endsWith(htmlExtension)) {
    const last = segments.pop()
    if (last) {
      segments.push(last.slice(0, -1 * htmlExtension.length))
    }
  }

  return segments.filter(Boolean).join('/')
}

export function normalizePathname(pathname: string, base: string) {
  return ensureTrailingSlash(base === '/' ? stripLeadingSlash(pathname) : posix.join(stripLeadingSlash(base), pathname))
}