// @ts-check

import { getInnerText } from '@redocly/realm/dist/server/plugins/markdown/markdoc/helpers/get-inner-text.js'

import { dirname, relative, join as joinPath } from 'path'

export function codeSamples() {
  /** @type {import("@redocly/realm/dist/server/plugins/types").PluginInstance } */
  const instance = {
    processContent: async (actions, { fs, cache }) => {
      try {
        const samples = []
        const allLands = new Set()
        const allCodeSampleFiles = await fs.scan()

        const readmes = allCodeSampleFiles.filter((file) => file.relativePath.match(/^_code-samples[\/\\]([^\\\/]*)[\/\\]README\.md$/))

        for (const { relativePath } of readmes) {
          const { data } = await cache.load(relativePath, 'markdown-ast')

          const dirPath = dirname(relativePath)
          const langs = unique(
            allCodeSampleFiles
              .filter((file) => file.relativePath.startsWith(dirPath) && !file.relativePath.endsWith('README.md'))
              .map((file) => relative(dirPath, file.relativePath).split('/')[0]),
          )
          const title = extractFirstHeading(data.ast) || ''
          samples.push({
            path: dirPath,
            title: title || toTitleCase(dirname(dirPath)),
            description: getInnerText([data.ast.children[1]]).trim(),
            href: joinPath('content', dirPath),
            langs,
          })

          langs.forEach((l) => allLands.add(l))
        }

        const sortedSamples = samples.sort((a, b) => normalizeTitleForSort(a).localeCompare(normalizeTitleForSort(b)))

        actions.createSharedData('code-samples', {
          codeSamples: sortedSamples,
          langs: Array.from(allLands),
        })
        actions.addRouteSharedData('/resources/code-samples/', 'code-samples', 'code-samples')
        actions.addRouteSharedData('/ja/resources/code-samples/', 'code-samples', 'code-samples')
        actions.addRouteSharedData('/es-es/resources/code-samples/', 'code-samples', 'code-samples')
      } catch (e) {
        console.log(e)
      }
    },
  }
  return instance
}

function normalizeTitleForSort(cs) {
  if (cs.title.includes('Intro') || cs.title.includes('Quickstart')) {
    return ` ${cs.title}`
  }
  return cs.title
}

const WORDS_TO_CAPS = ['xrp']

function toTitleCase(s) {
  const words = s.split(/_|[^\w']/)
  return words
    .filter((word) => word)
    .map((word) => (WORDS_TO_CAPS.includes(word) ? word.toUpperCase() : word.charAt(0).toUpperCase() + word.slice(1)))
    .join(' ')
    .replace("'S", "'s")
    .replace(' A ', ' a ')
}

function unique(array) {
  return Array.from(new Set(array))
}

function extractFirstHeading(ast) {
  let heading

  visit(ast, (node) => {
    if (!isNode(node)) {
      return
    }

    if (node.type === 'heading') {
      heading = getInnerText([node])
      return EXIT
    }
  })

  return heading
}

function isNode(value) {
  return !!(value?.$$mdtype === 'Node')
}

const EXIT = Symbol('Exit visitor')
function visit(node, visitor) {
  if (!node) return

  const res = visitor(node)
  if (res === EXIT) return res

  for (const child of node.children) {
    if (!child || typeof child === 'string') {
      continue
    }
    const res = visit(child, visitor)
    if (res === EXIT) return res
  }
}