import QParser from 'q2filter'

export function escapeRegExp (s: string) {
  return s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&') // $& means the whole matched string
}

export function normalizeArray<T> (it: T | T[]): T | undefined {
  if (Array.isArray(it)) {
    return it[0]
  }

  return it
}

export function searchPosts (options: {
  q?: any
  isBlog?: boolean
  current?: boolean
  posts: any[]
}) {
  let posts: any[] = options.posts

  if (options.isBlog) {
    posts = posts.filter((p) => p.path.startsWith('blog/'))
  }

  if (options.current) {
    const now = new Date().toISOString()
    posts = posts.filter((h) => h.date && h.date <= now)
  }

  const parser = new QParser(options.q || {}, {
    isString: ['title', 'author', 'tag'],
    isDate: ['date'],
    filters: {
      'is:reversed': (items) => {
        return items.reverse()
      },
    },
    sortBy: {
      key: 'date',
      desc: true,
    },
  })

  return parser.parse(posts)
}

export async function apiHash (u: string, h: string): Promise<string> {
  if (typeof location !== 'undefined') {
    const url = new URL(u, location.origin)
    url.searchParams.set('h', h)
    return fetch(url.href, {
      mode: 'no-cors',
    }).then((r) => r.text())
  } else {
    if (/\.json$/i.test(u)) {
      const req = (require as any).context('@/static', true, /\.json$/i)
      return JSON.stringify(req(`.${u}`))
    } else {
      const req = (require as any).context('@/static', true, /\.(html?|md|txt|ya?ml)$/i)
      return req(`.${u}`).default
    }
  }
}