export const uniqueArray = originalArray => [...new Set(originalArray)]

export function slugify(textToSlugify) {
  return textToSlugify
    .toLowerCase()
    .replace(/[^\w\s-]/g, '') // remove non-word [a-z0-9_], non-whitespace, non-hyphen characters
    .replace(/[\s_-]+/g, '-') // swap any length of whitespace, underscore, hyphen characters with a single -
    .replace(/^-+|-+$/g, '') // remove leading, trailing -
}

export const createTagsList = (postsArray) => {
  const tagsArray = []
  postsArray.forEach((post) => {
    if (post.tags.length) {
      post.tags.forEach(tag => tagsArray.push(tag))
    }
  })
  return uniqueArray(tagsArray)
}

export const getPostsFromTag = (posts, tag) =>
  posts.filter(post => post.tags.map(tag => slugifyText(tag)).includes(tag))

export const slugifyText = str =>
  slugify(str, { replacement: '-', lower: true, remove: /[$*_+~.()'"!\-:@]/g })

export const arrayToObject = (arr, keyField) =>
  Object.assign({}, ...arr.map(item => ({ [item[keyField]]: item })))

export const arrayFromObject = object =>
  Object.keys(object).map(key => object[key])