Computer.js

const lodash = require("lodash")
const path = require("path")
const { Particle } = require("scrollsdk/products/Particle.js")
const { Disk } = require("scrollsdk/products/Disk.node.js")
const { Utils } = require("scrollsdk/products/Utils.js")
const { shiftRight, removeReturnChars } = Utils
const ParserFile = new Particle(Disk.read(path.join(__dirname, "code", "measures.parsers")))
const listsFolder = path.join(__dirname, "lists")
const pagesDir = path.join(__dirname, "pages")
const numeral = require("numeral")
const dayjs = require("dayjs")

const currentYear = new Date().getFullYear()
const cleanAndRightShift = (str, count = 1) => Utils.shiftRight(Utils.removeReturnChars(str), count)

const linkManyAftertext = links =>
  links.map((link, index) => `${index + 1}.`).join(" ") + // notice the dot is part of the link. a hack to make it more unique for aftertext matching.
  links.map((link, index) => `\n ${link} ${index + 1}.`).join("")

const makePrettyUrlLink = url => `<a href="${url}">${new URL(url).hostname}</a>`

// Sigh. After learning Material Designs realized
// it's partially broken on purpose:
// https://github.com/google/material-design-icons/issues/166
const SVGS = {
  leetSheet: `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24">
  <text x="12" y="9" font-family="Monospace" font-size="8" fill="black" text-anchor="middle" dominant-baseline="middle">LEET</text>
  <text x="12" y="17" font-family="Monospace" font-size="6" fill="black" text-anchor="middle" dominant-baseline="middle">SHEET</text>
 </svg>`,
  git: `<svg xmlns="http://www.w3.org/2000/svg" width="92pt" height="92pt" viewBox="0 0 92 92"><path d="M90.156 41.965 50.036 1.848a5.913 5.913 0 0 0-8.368 0l-8.332 8.332 10.566 10.566a7.03 7.03 0 0 1 7.23 1.684 7.043 7.043 0 0 1 1.673 7.277l10.183 10.184a7.026 7.026 0 0 1 7.278 1.672 7.04 7.04 0 0 1 0 9.957 7.045 7.045 0 0 1-9.961 0 7.038 7.038 0 0 1-1.532-7.66l-9.5-9.497V59.36a7.04 7.04 0 0 1 1.86 11.29 7.04 7.04 0 0 1-9.957 0 7.04 7.04 0 0 1 0-9.958 7.034 7.034 0 0 1 2.308-1.539V33.926a7.001 7.001 0 0 1-2.308-1.535 7.049 7.049 0 0 1-1.516-7.7L29.242 14.273 1.734 41.777a5.918 5.918 0 0 0 0 8.371L41.855 90.27a5.92 5.92 0 0 0 8.368 0l39.933-39.934a5.925 5.925 0 0 0 0-8.371"/></svg>`,
  twitter: `<svg role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M23.953 4.57a10 10 0 01-2.825.775 4.958 4.958 0 002.163-2.723c-.951.555-2.005.959-3.127 1.184a4.92 4.92 0 00-8.384 4.482C7.69 8.095 4.067 6.13 1.64 3.162a4.822 4.822 0 00-.666 2.475c0 1.71.87 3.213 2.188 4.096a4.904 4.904 0 01-2.228-.616v.06a4.923 4.923 0 003.946 4.827 4.996 4.996 0 01-2.212.085 4.936 4.936 0 004.604 3.417 9.867 9.867 0 01-6.102 2.105c-.39 0-.779-.023-1.17-.067a13.995 13.995 0 007.557 2.209c9.053 0 13.998-7.496 13.998-13.985 0-.21 0-.42-.015-.63A9.935 9.935 0 0024 4.59z"/></svg>`,
  reddit: `<svg role="img" width="32px" height="32px" viewBox="0 0 32 32" xmlns="http://www.w3.org/2000/svg"><path d="M 18.65625 4 C 16.558594 4 15 5.707031 15 7.65625 L 15 11.03125 C 12.242188 11.175781 9.742188 11.90625 7.71875 13.0625 C 6.945313 12.316406 5.914063 12 4.90625 12 C 3.816406 12 2.707031 12.355469 1.9375 13.21875 L 1.9375 13.25 L 1.90625 13.28125 C 1.167969 14.203125 0.867188 15.433594 1.0625 16.65625 C 1.242188 17.777344 1.898438 18.917969 3.03125 19.65625 C 3.023438 19.769531 3 19.882813 3 20 C 3 22.605469 4.574219 24.886719 6.9375 26.46875 C 9.300781 28.050781 12.488281 29 16 29 C 19.511719 29 22.699219 28.050781 25.0625 26.46875 C 27.425781 24.886719 29 22.605469 29 20 C 29 19.882813 28.976563 19.769531 28.96875 19.65625 C 30.101563 18.917969 30.757813 17.777344 30.9375 16.65625 C 31.132813 15.433594 30.832031 14.203125 30.09375 13.28125 L 30.0625 13.25 C 29.292969 12.386719 28.183594 12 27.09375 12 C 26.085938 12 25.054688 12.316406 24.28125 13.0625 C 22.257813 11.90625 19.757813 11.175781 17 11.03125 L 17 7.65625 C 17 6.675781 17.558594 6 18.65625 6 C 19.175781 6 19.820313 6.246094 20.8125 6.59375 C 21.65625 6.890625 22.75 7.21875 24.15625 7.3125 C 24.496094 8.289063 25.414063 9 26.5 9 C 27.875 9 29 7.875 29 6.5 C 29 5.125 27.875 4 26.5 4 C 25.554688 4 24.738281 4.535156 24.3125 5.3125 C 23.113281 5.242188 22.246094 4.992188 21.46875 4.71875 C 20.566406 4.402344 19.734375 4 18.65625 4 Z M 16 13 C 19.152344 13 21.964844 13.867188 23.9375 15.1875 C 25.910156 16.507813 27 18.203125 27 20 C 27 21.796875 25.910156 23.492188 23.9375 24.8125 C 21.964844 26.132813 19.152344 27 16 27 C 12.847656 27 10.035156 26.132813 8.0625 24.8125 C 6.089844 23.492188 5 21.796875 5 20 C 5 18.203125 6.089844 16.507813 8.0625 15.1875 C 10.035156 13.867188 12.847656 13 16 13 Z M 4.90625 14 C 5.285156 14 5.660156 14.09375 5.96875 14.25 C 4.882813 15.160156 4.039063 16.242188 3.53125 17.4375 C 3.277344 17.117188 3.125 16.734375 3.0625 16.34375 C 2.953125 15.671875 3.148438 14.976563 3.46875 14.5625 C 3.472656 14.554688 3.464844 14.539063 3.46875 14.53125 C 3.773438 14.210938 4.3125 14 4.90625 14 Z M 27.09375 14 C 27.6875 14 28.226563 14.210938 28.53125 14.53125 C 28.535156 14.535156 28.527344 14.558594 28.53125 14.5625 C 28.851563 14.976563 29.046875 15.671875 28.9375 16.34375 C 28.875 16.734375 28.722656 17.117188 28.46875 17.4375 C 27.960938 16.242188 27.117188 15.160156 26.03125 14.25 C 26.339844 14.09375 26.714844 14 27.09375 14 Z M 11 16 C 9.894531 16 9 16.894531 9 18 C 9 19.105469 9.894531 20 11 20 C 12.105469 20 13 19.105469 13 18 C 13 16.894531 12.105469 16 11 16 Z M 21 16 C 19.894531 16 19 16.894531 19 18 C 19 19.105469 19.894531 20 21 20 C 22.105469 20 23 19.105469 23 18 C 23 16.894531 22.105469 16 21 16 Z M 21.25 21.53125 C 20.101563 22.597656 18.171875 23.28125 16 23.28125 C 13.828125 23.28125 11.898438 22.589844 10.75 21.65625 C 11.390625 23.390625 13.445313 25 16 25 C 18.554688 25 20.609375 23.398438 21.25 21.53125 Z"/></svg>`,
  wikipedia: `<svg version="1.1" id="Capa_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" width="98.05px" height="98.05px" viewBox="0 0 98.05 98.05" style="enable-background:new 0 0 98.05 98.05;" xml:space="preserve"><path d="M98.023,17.465l-19.584-0.056c-0.004,0.711-0.006,1.563-0.017,2.121c1.664,0.039,5.922,0.822,7.257,4.327L66.92,67.155 c-0.919-2.149-9.643-21.528-10.639-24.02l9.072-18.818c1.873-2.863,5.455-4.709,8.918-4.843l-0.01-1.968L55.42,17.489 c-0.045,0.499,0.001,1.548-0.068,2.069c5.315,0.144,7.215,1.334,5.941,4.508c-2.102,4.776-6.51,13.824-7.372,15.475 c-2.696-5.635-4.41-9.972-7.345-16.064c-1.266-2.823,1.529-3.922,4.485-4.004v-1.981l-21.82-0.067 c0.016,0.93-0.021,1.451-0.021,2.131c3.041,0.046,6.988,0.371,8.562,3.019c2.087,4.063,9.044,20.194,11.149,24.514 c-2.685,5.153-9.207,17.341-11.544,21.913c-3.348-7.43-15.732-36.689-19.232-44.241c-1.304-3.218,3.732-5.077,6.646-5.213 l0.019-2.148L0,17.398c0.005,0.646,0.027,1.71,0.029,2.187c4.025-0.037,9.908,6.573,11.588,10.683 c7.244,16.811,14.719,33.524,21.928,50.349c0.002,0.029,2.256,0.059,2.281,0.008c4.717-9.653,10.229-19.797,15.206-29.56 L63.588,80.64c0.005,0.004,2.082,0.016,2.093,0.007c7.962-18.196,19.892-46.118,23.794-54.933c1.588-3.767,4.245-6.064,8.543-6.194 l0.032-1.956L98.023,17.465z"/></svg>`,
  youtube: `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M23.498 6.186a3.016 3.016 0 0 0-2.122-2.136C19.505 3.545 12 3.545 12 3.545s-7.505 0-9.377.505A3.017 3.017 0 0 0 .502 6.186C0 8.07 0 12 0 12s0 3.93.502 5.814a3.016 3.016 0 0 0 2.122 2.136c1.871.505 9.376.505 9.376.505s7.505 0 9.377-.505a3.015 3.015 0 0 0 2.122-2.136C24 15.93 24 12 24 12s0-3.93-.502-5.814zM9.545 15.568V8.432L15.818 12l-6.273 3.568z"/></svg>`,
  tiktok: `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12.53.02C13.84 0 15.14.01 16.44 0c.08 1.53.63 3.09 1.75 4.17 1.12 1.11 2.7 1.62 4.24 1.79v4.03c-1.44-.05-2.89-.35-4.2-.97-.57-.26-1.1-.59-1.62-.93-.01 2.92.01 5.84-.02 8.75-.08 1.4-.54 2.79-1.35 3.94-1.31 1.92-3.58 3.17-5.91 3.21-1.43.08-2.86-.31-4.08-1.03-2.02-1.19-3.44-3.37-3.65-5.71-.02-.5-.03-1-.01-1.49.18-1.9 1.12-3.72 2.58-4.96 1.66-1.44 3.98-2.13 6.15-1.72.02 1.48-.04 2.96-.04 4.44-.99-.32-2.15-.23-3.02.37-.63.41-1.11 1.04-1.36 1.75-.21.51-.15 1.07-.14 1.61.24 1.64 1.82 3.02 3.5 2.87 1.12-.01 2.19-.66 2.77-1.61.19-.33.4-.67.41-1.06.1-1.79.06-3.57.07-5.36.01-4.03-.01-8.05.02-12.07z"/></svg>`
}

const delimiter = `¶`
const quickTable = (rows, header) =>
  `datatable\n delimiter ${delimiter}\n printTable\n data\n  ${new Particle(rows)
    .toDelimited(delimiter, header, false)
    .replace(/\n/g, "\n  ")}`

// todo: move to Parsers
const languageTags = new Set(
  `assembly
barCodeFormat
bytecode
characterEncoding
compiler
configFormat
contractLanguage
dataNotation
dataVis
dataFlow
dataValidationLanguage
diagramLang
diffFormat
esolang
grammarLanguage
hardwareDescriptionLanguage
headerLang
idl
interpreter
ir
isa
jsonFormat
library
musicalNotation
notation
numeralSystem
pl
plzoo
protocol
queryLanguage
schema
standard
staticSiteGenerator
stylesheetLanguage
template
textDataFormat
textEncodingFormat
textMarkup
timeFormat
unixApplication
visual
wikiMarkup
xmlFormat
yamlFormat`.split("\n")
)
const isLanguage = tag => languageTags.has(tag)

// Todo: move to Parsers with an enum concept?
const tagNames = new Particle(`application
assembly assembly language
binaryDataFormat
binaryExecutable binary executable format
bytecode bytecode format
characterEncoding
cloud cloud service
commandLineApp command line application
compiler
dataVis data visualization grammar
dataFlow dataflow grammar
editor
esolang esoteric programming language
filesystem
framework
grammarLanguage
idl interface design language
interpreter
ir intermediate representation language
isa instruction set architecture
jsonFormat
library
linter
metalanguage
notation
os operating system
packageManager
feature language feature
pl programming language
plzoo minilanguage
protocol
queryLanguage
schema
standard
staticSiteGenerator static site generator
stylesheetLanguage
template template language
textData text data format
textMarkup text markup language
visual visual programming language
vm virtual machine
webApi
xmlFormat`).toObject()

const PLDBKeywords = {
  tags: "tags"
}

class ConceptPage {
  constructor(parsed, tables) {
    this.absolutePath = path.join(__dirname, "concepts", parsed.id + ".scroll")
    this.tables = tables
    this.parsed = parsed
    this.particle = new Particle(Disk.read(this.absolutePath))
    this.quickCache = {}
  }

  get id() {
    return this.parsed.id
  }

  get(Atom) {
    return this.particle.get(Atom)
  }

  getParticle(Atom) {
    return this.particle.getParticle(Atom)
  }

  get filePath() {
    return this._getFilePath()
  }

  get permalink() {
    return this.id + ".html"
  }

  get domainName() {
    return this.get("domainName")
  }

  get subredditId() {
    return this.get("subreddit")?.split("/").pop()
  }

  get bookCount() {
    if (this.quickCache.bookCount !== undefined) return this.quickCache.bookCount
    const gr = this.getParticle(`goodreads`)?.length
    const isbndb = this.getParticle(`isbndb`)?.length
    let count = 0
    if (gr) count += gr - 1
    if (isbndb) count += isbndb - 1
    this.quickCache.bookCount = count
    return count
  }

  get paperCount() {
    if (this.quickCache.paperCount !== undefined) return this.quickCache.paperCount
    const ss = this.getParticle(`semanticScholar`)?.length

    let count = 0
    if (ss) count += ss - 1
    this.quickCache.paperCount = count
    return count
  }

  get hoplId() {
    return this.get("hopl")?.replace("https://hopl.info/showlanguage.prx?exp=", "")
  }

  get helpfulResearchLinks() {
    const id = this.id
    const title = this.get("name")
    const references = this.particle
      .findParticles("reference")
      .map(particle => "Reference: " + particle.content)
      .join("\n")
    const links = ["website", "githubRepo", "wikipedia"]
      .filter(key => this.has(key))
      .map(key => `${Utils.capitalizeFirstLetter(key)}: ${this.get(key)}`)
      .join("\n")
    const searchEngines = `Google: https://www.google.com/search?q=${title}+programming+language
Google w/time: https://www.google.com/search?q=${title}+programming+language&tbs=cdr%3A1%2Ccd_min%3A1%2F1%2F1980%2Ccd_max%3A12%2F31%2F1995&tbm=
Google Scholar: https://scholar.google.com/scholar?q=${title}
Google Groups: https://groups.google.com/forum/#!search/${title}
Google Trends: https://trends.google.com/trends/explore?date=all&q=${title}
DDG: https://duckduckgo.com/?q=${title}
Wayback Machine: https://web.archive.org/web/20220000000000*/${title}`

    return (
      `<br><h3>Links for researching ${title}</h3>` +
      (links + references + "\n" + searchEngines)
        .split("\n")
        .map(line => {
          const parts = line.split(": ")
          return `<a href="${parts[1]}">${parts[0]}</a>`
        })
        .join("<br>")
    )
  }

  get names() {
    return [
      this.id,
      this.name,
      this.get("standsFor"),
      this.get("githubLanguage"),
      this.wikipediaTitle,
      ...this.getAll("aka")
    ].filter(i => i)
  }

  get fileExtension() {
    return this.extensions.split(" ")[0]
  }

  get keywords() {
    const kw = this.get("keywords")
    return kw ? kw.split(" ") : []
  }

  get repl() {
    return this.particle.getOneOf("webRepl tryItOnline replit rijuRepl".split(" "))
  }

  get lineCommentToken() {
    return this.get("lineCommentToken")
  }

  get previousRanked() {
    return this.tables.getFileAtRank(this.rank - 1)
  }

  get nextRanked() {
    return this.tables.getFileAtRank(this.rank + 1)
  }

  get exampleCount() {
    return this.allExamples.length + this.featuresWithExamples.length
  }

  // Todo: make this a general Scroll feature
  // Support inheritance in the dataset. Entities can extend from other entities and override
  // only the column values where they are different.
  get extended() {
    return this.particle // todo
    if (this.quickCache.extended) return this.quickCache.extended
    const extendedFile = this.getRelationshipFile("supersetOf") || this.getRelationshipFile("implementationOf")
    this.quickCache.extended = extendedFile ? extendedFile.patch(this) : this
    return this.quickCache.extended
  }

  get features() {
    const featuresMap = this.tables.featuresMap
    return this.extended.filter(particle => featuresMap.has(particle.getAtom(0)))
  }

  get featuresWithExamples() {
    return this.features.filter(particle => particle.length)
  }

  get lab() {
    const lab = this.get("lab")
    return lab ? lab.split(" && ") : []
  }

  get creators() {
    return this.get("creators")?.split(" and ") ?? []
  }

  get maintainers() {
    return this.get("maintainers")?.split(" and ") ?? []
  }

  get hasBooleansPrediction() {
    const { keywords } = this

    const pairs = ["true false", "TRUE FALSE", "True False"]

    let hit
    pairs.forEach(pair => {
      const parts = pair.split(" ")
      if (keywords.includes(parts[0]) && keywords.includes(parts[1]))
        hit = {
          value: true,
          token: pair
        }
    })

    if (hit) return hit

    const examples = this.allExamples.map(code => code.code)
    pairs.forEach(pair => {
      const parts = pair.split(" ")

      const hasTrue = examples.some(code => code.includes(parts[0]))
      const hasFalse = examples.some(code => code.includes(parts[1]))

      if (hasTrue && hasFalse)
        hit = {
          value: true,
          token: pair
        }
    })

    return hit
  }

  get hasImportsPrediction() {
    const { keywords } = this

    const Atoms = ["import", "include", "require"]

    for (let Atom of Atoms) {
      if (keywords.includes(Atom)) {
        const example = this.allExamples.find(code => code.code.includes(Atom))

        if (example) {
          const exampleLine = example.code.split("\n").filter(line => line.includes(Atom))[0]
          return {
            value: true,
            token: Atom,
            example: exampleLine
          }
        } else {
          console.log(`No example found for ${this.id}`)
        }
      }
    }
  }

  makeSimpleKeywordPrediction(theAtom) {
    const { keywords } = this

    if (keywords.includes(theAtom))
      return {
        value: true
      }
  }

  get hasWhileLoopsPrediction() {
    return this.makeSimpleKeywordPrediction("while")
  }

  get hasClassesPrediction() {
    return this.makeSimpleKeywordPrediction("class")
  }

  get hasConstantsPrediction() {
    return this.makeSimpleKeywordPrediction("const")
  }

  get hasExceptionsPrediction() {
    return this.makeSimpleKeywordPrediction("throw")
  }

  get hasSwitchPrediction() {
    return this.makeSimpleKeywordPrediction("switch")
  }

  get hasAccessModifiersPrediction() {
    return this.makeSimpleKeywordPrediction("public")
  }

  get hasInheritancePrediction() {
    return this.makeSimpleKeywordPrediction("extends")
  }

  get hasAsyncAwaitPrediction() {
    return this.makeSimpleKeywordPrediction("async")
  }

  get hasConditionalsPrediction() {
    return this.makeSimpleKeywordPrediction("if")
  }

  get hasFunctionsPrediction() {
    return (
      this.makeSimpleKeywordPrediction("function") ||
      this.makeSimpleKeywordPrediction("fun") ||
      this.makeSimpleKeywordPrediction("def")
    )
  }

  get allExamples() {
    const examples = []

    this.particle.findParticles("example").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "the web",
        link: ""
      })
    })

    this.particle.findParticles("compilerExplorer example").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "Compiler Explorer",
        link: `https://godbolt.org/`
      })
    })

    this.particle.findParticles("rijuRepl example").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "Riju",
        link: this.get("rijuRepl")
      })
    })

    this.particle.findParticles("leachim6").forEach(particle => {
      examples.push({
        code: particle.getParticle("example").subparticlesToString(),
        source: "hello-world",
        link: `https://github.com/leachim6/hello-world/blob/main/` + particle.get("filepath")
      })
    })

    this.particle.findParticles("helloWorldCollection").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "the Hello World Collection",
        link: `http://helloworldcollection.de/#` + particle.getAtom(1)
      })
    })

    const linguist_url = this.get("linguistGrammarRepo")
    this.particle.findParticles("linguistGrammarRepo example").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "Linguist",
        link: linguist_url
      })
    })

    this.particle.findParticles("wikipedia example").forEach(particle => {
      examples.push({
        code: particle.subparticlesToString(),
        source: "Wikipedia",
        link: this.get("wikipedia")
      })
    })

    return examples
  }

  getMostRecentInt(pathToSet) {
    let set = this.getParticle(pathToSet)
    if (!set) return 0
    set = set.toObject()
    const key = Math.max(...Object.keys(set).map(year => parseInt(year)))
    return parseInt(set[key])
  }

  get appeared() {
    const appeared = this.get("appeared")
    return appeared === undefined ? 0 : parseInt(appeared)
  }

  get website() {
    return this.get("website")
  }

  get primaryTag() {
    return this.get(PLDBKeywords.tags).split(" ")[0]
  }

  get isLanguage() {
    // todo: add a "cl" enum tag, then just search tags for that string.
    return isLanguage(this.get(PLDBKeywords.tags))
  }

  get otherReferences() {
    return this.particle.findParticles("reference").map(line => line.content)
  }

  get wikipediaTitle() {
    const wp = this.get("wikipedia")
    return wp ? wp.replace("https://en.wikipedia.org/wiki/", "").trim() : ""
  }

  get numberOfUsersEstimate() {
    return this.parsed.numberOfUsers
  }

  get numberOfJobsEstimate() {
    return this.parsed.numberOfJobs
  }

  get percentile() {
    return this.parent.predictPercentile(this)
  }

  getRelationshipFile(relationshipType) {
    const hit = this.get(relationshipType)
    return hit ? this.tables.getConceptPage(hit) : undefined
  }

  get rank() {
    return this.parsed.rank
  }

  link(baseFolder = "") {
    return `<a href="${baseFolder + this.permalink}">${this.name}</a>`
  }

  get extensions() {
    return getJoined(this, [
      "fileExtensions",
      "clocExtensions",
      "githubLanguage fileExtensions",
      "pygmentsHighlighter fileExtensions",
      "wikipedia fileExtensions"
    ])
  }

  get primaryTagName() {
    let { primaryTag } = this
    primaryTag = tagNames[primaryTag] || primaryTag
    return lodash.startCase(primaryTag).toLowerCase()
  }

  get lastActivity() {
    return lodash.max(this.parsed.findAllAtomsWithAtomType("yearAtom").map(Atom => parseInt(Atom.Atom)))
  }

  makeATag(id) {
    const file = this.tables.getConceptPage(id)
    if (!file) throw new Error(`Cant find file '${id}'`)
    return `<a href="${file.permalink}">${file.name}</a>`
  }

  get trendingRepos() {
    const { title } = this
    const count = this.get(`$githubLanguage trendingProjectsCount`)
    if (parseInt(count) > 0) {
      const table = this.getParticle("githubLanguage trendingProjects")
      const githubId = this.get("githubLanguage")

      if (!table) {
        console.log(`Error with ${this.id}`)
        return ""
      }

      const particle = Particle.fromSsv(table.subparticlesToString())
      particle.forEach(subparticle => {
        subparticle.set("repo", subparticle.get("name"))
        subparticle.set("repoLink", subparticle.get("url"))
      })
      return `## Trending <a href="https://github.com/trending/${githubId}?since=monthly">${title} repos</a> on GitHub
datatable
 delimiter ,
 printTable
 data
  ${cleanAndRightShift(particle.toDelimited(",", ["repo", "repoLink", "stars", "description"]), 2)}
`
    }
    return ""
  }

  get semanticScholar() {
    const { title } = this
    const items = this.getParticle(`semanticScholar`)
    if (!items) return ""

    if (items.content === "0") return ""

    const particle = Particle.fromDelimited(items.subparticlesToString(), "|")
    particle.forEach(subparticle => {
      subparticle.set("titleLink", `https://www.semanticscholar.org/paper/${subparticle.get("paperId")}`)
    })
    return `## Publications about ${title} from Semantic Scholar
datatable
 delimiter |
 printTable
 data
  ${
    (cleanAndRightShift(
      particle.toDelimited("|", ["title", "titleLink", "authors", "year", "citations", "influentialCitations"])
    ),
    2)
  }
`
  }

  get isbndb() {
    const { title } = this
    const isbndb = this.getParticle(`isbndb`)
    if (!isbndb) return ""

    if (isbndb.content === "0") return ""

    const particle = Particle.fromDelimited(isbndb.subparticlesToString(), "|")
    particle.forEach(subparticle => {
      subparticle.set("titleLink", `https://isbndb.com/book/${subparticle.get("isbn13")}`)
    })
    return `## Books about ${title} from ISBNdb
datatable
 delimiter |
 printTable
 data
  ${cleanAndRightShift(particle.toDelimited("|", ["title", "titleLink", "authors", "year", "publisher"]), 2)}
`
  }

  get goodreads() {
    const { title } = this
    const goodreads = this.getParticle(`goodreads`) // todo: the goodreadsIds we have are wrong.
    if (!goodreads) return ""

    const particle = Particle.fromDelimited(goodreads.subparticlesToString(), "|")
    particle.forEach(subparticle => {
      subparticle.set(
        "titleLink",
        `https://www.goodreads.com/search?q=${subparticle.get("title") + " " + subparticle.get("author")}`
      )
    })
    return `## Books about ${title} on goodreads
datatable
 delimiter |
 printTable
 data
  ${cleanAndRightShift(
    particle.toDelimited("|", ["title", "titleLink", "author", "year", "reviews", "ratings", "rating"]),
    2
  )}
`
  }

  get publications() {
    const { title } = this
    const dblp = this.getParticle(`dblp`)
    if (dblp && dblp.get("hits") !== "0") {
      const particle = Particle.fromDelimited(dblp.getParticle("publications").subparticlesToString(), "|")
      particle.forEach(subparticle => {
        subparticle.set(
          "titleLink",
          subparticle.get("doi") ? `https://doi.org/` + subparticle.get("doi") : subparticle.get("url")
        )
      })
      return `## ${dblp.get("hits")} publications about ${title} on <a href="${this.get("dblp")}">DBLP</a>
datatable
 delimiter |
 printTable
 data
  ${cleanAndRightShift(particle.toDelimited("|", ["title", "titleLink", "year"]), 2)}
`
    }
    return ""
  }

  get featuresTable() {
    const { features, id } = this
    if (!features.length) return ""

    const { featuresMap } = this.tables
    const table = new Particle()
    features.forEach(particle => {
      const feature = featuresMap.get(particle.getAtom(0))
      if (!feature) {
        console.log(`warning: we need a features page for feature '${particle.getAtom(0)}' found in '${id}'`)
        return
      }

      const tokenPath = feature.token
      const supported = particle.content === "true"

      table
        .appendLineAndSubparticles(
          `row`,
          `Feature ${feature.title}
FeatureLink ${feature.titleLink}
Supported ${supported ? `<span class="hasFeature">✓</span>` : `<span class="doesNotHaveFeature">X</span>`}
Example
Token ${supported && tokenPath ? (this.get(tokenPath) ?? "") : ""}`
        )
        .touchParticle("Example")
        .setSubparticles(particle.subparticlesToString())
    })

    return `## Language <a href="../lists/features.html">features</a>

datatable
 delimiter particles
 printTable
 data
  ${table.sortBy(["Supported", "Example"]).reverse().toString().replace(/\n/g, "\n  ")}`
  }

  get hackerNewsTable() {
    const hnTable = this.getParticle(`hackerNewsDiscussions`)?.subparticlesToString()
    if (!hnTable) return ""

    const table = Particle.fromDelimited(hnTable, "|")
    table.forEach(row => {
      row.set("titleLink", `https://news.ycombinator.com/item?id=${row.get("id")}`)
      row.set("date", dayjs(row.get("time")).format("MM/DD/YYYY"))
    })

    const delimited = table
      .toDelimited("|", ["title", "titleLink", "date", "score", "comments"])
      .replace(/\n/g, "\n  ")
      .trim()
    return `## HackerNews discussions of ${this.name}

datatable
 delimiter |
 printTable
 data
  ${delimited}`
  }

  get title() {
    return this.get("name")
  }

  get name() {
    return this.get("name")
  }

  toScroll() {
    const { primaryTagName, title, id } = this

    if (title.includes("%20")) throw new Error("bad space in title: " + title)

    const { mainRepo } = this.parsed

    const sourceCode = mainRepo
      ? `codeWithHeader Download source code:
 git clone ${mainRepo}`
      : ""

    return `../header.scroll
baseUrl https://pldb.io/concepts/
title ${title} - ${lodash.upperFirst(primaryTagName)}

printTitle ${title}

<a class="trueBaseThemePreviousItem" href="${this.prevPage}">&lt;</a>
<a class="trueBaseThemeNextItem" href="${this.nextPage}">&gt;</a>

editBaseUrl https://github.com/breck7/pldb/blob/main/concepts/
// editBaseUrl /edit.html?folderName=pldb.io&fileName=concepts/

container 800px

<div class="trueBaseThemeQuickLinks">${this.quickLinks}</div>

${this.oneLiner}

${this.kpiBar}

${sourceCode}

${this.monacoEditor}

${this.quickTextLinks}

${this.image}

${this.descriptionSection}

${this.factsArray.map(fact => `- ${fact}\n inlineMarkupsOn none`).join("\n")}

br

${this.exampleSection}

${this.funFactSection}

${this.keywordsSection}

${this.featuresTable}

${this.trendingRepos}

${this.publications}

${this.hackerNewsTable}

keyboardNav ${this.prevPage} ${this.nextPage}

endColumns

../footer.scroll
`.replace(/\n\n\n+/g, "\n\n")
  }

  getAll(keyword) {
    return this.particle.findParticles(keyword).map(particle => particle.content)
  }

  get image() {
    const { title } = this

    let image = this.get("screenshot")
    let caption = `A screenshot of the ${this.primaryTagLink} ${title}.`
    if (!image) {
      image = this.get("photo")
      if (!image) return ""
      image = "photos/" + image
      caption = `A photo of ${title}.`
    } else image = "screenshots/" + image

    return `openGraphImage https://pldb.io/concepts/${image}
image ${image}
 caption ${caption}`
  }

  get monacoEditor() {
    const monaco = this.get("monaco")
    if (!monaco) return ""

    const exampleToUse = this.allExamples.find(example => !example.code.includes("`")) // our monaco code struggles with backticks for some reason.

    const example = exampleToUse ? exampleToUse.code.replace(/\n/g, "\n ") : ""

    return `monacoEditor ${monaco}
 ${example}`
  }

  get prevPage() {
    return this.previousRanked.permalink
  }

  get nextPage() {
    return this.nextRanked.permalink
  }

  get quickTextLinks() {
    const links = {
      Homepage: this.website,
      "Leet Sheet": this.getPrimary("leetSheets"),
      REPL: this.repl,
      "Try It Online": this.get("tryItOnline"),
      Download: this.get("download"),
      "Source Code": this.parsed.mainRepo,
      Spec: this.getPrimary("spec"),
      Blog: this.get("blog"),
      Wikipedia: this.get(`wikipedia`),
      Subreddit: this.get("subreddit"),
      Twitter: this.get("twitter"),
      FAQ: this.getPrimary("faq"),
      "Release Notes": this.getPrimary("releaseNotes"),
      "Demo Video": this.get("demoVideo"),
      Docs: this.getPrimary("docs"),
      "Mailing List": this.getPrimary("emailList")
    }
    return Object.keys(links)
      .map(key => (links[key] ? `<a href="${links[key]}">${key}</a>` : ""))
      .filter(i => i)
      .join(" · ")
  }

  get quickLinks() {
    const links = {
      home: this.website,
      leetSheet: this.getPrimary("leetSheets"),
      terminal: this.repl,
      git: this.parsed.mainRepo,
      newspaper: this.get("blog"),
      wikipedia: this.get(`wikipedia`),
      reddit: this.get("subreddit"),
      youtube: this.getPrimary("youtubes"),
      tiktok: this.getPrimary("tiktoks"),
      festival: this.getPrimary("conferences"),
      twitter: this.get("twitter"),
      edit: `https://github.com/breck7/pldb/blob/main/concepts/${this.id}.scroll`
    }
    return Object.keys(links)
      .filter(key => links[key])
      .map(key =>
        SVGS[key]
          ? `<a href="${links[key]}">${SVGS[key]}</a>`
          : `<a href="${links[key]}" class="material-symbols-outlined">${key}</a>`
      )
      .join(" ")
  }

  get sourceStatus() {
    const value = this.get("isOpenSource")
    if (value === undefined) return ""
    return value ? " open source" : " closed source"
  }

  get oneLiner() {
    const { primaryTagName, title, creators, appeared, sourceStatus, maintainers } = this
    const standsFor = this.get("standsFor")
    let akaMessage = standsFor ? `, aka ${standsFor},` : ""

    let creatorsStr = ""
    let creatorsLinks = ""
    if (creators.length) {
      creatorsStr = ` by ` + creators.join(" and ")
      creatorsLinks = creators
        .map(name => ` link ../lists/creators.html#q=${encodeURIComponent(name)} ${name}`)
        .join("\n")
    }

    let maintainersStr = ""
    let maintainersLinks = ""
    if (maintainers.length) {
      maintainersStr = ` and led by ` + maintainers.join(" and ")
      maintainersLinks = maintainers
        .map(name => ` link ../lists/creators.html#q=${encodeURIComponent(name)} ${name}`)
        .join("\n")
    }

    return `* ${title}${akaMessage} is ${Utils.getIndefiniteArticle(sourceStatus || primaryTagName)}${sourceStatus} ${
      this.primaryTagLink
    }${appeared ? ` created in ${appeared}` : ""}${creatorsStr}${maintainersStr}.
 link ../lists/explorer.html#searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22%3D%22%2C%22data%22%3A%22appeared%22%2C%22origData%22%3A%22appeared%22%2C%22tags%22%3A%22num%22%2C%22value%22%3A%5B%22${appeared}%22%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D ${appeared}
${creatorsLinks}
${maintainersLinks}
`
  }

  get primaryTagLink() {
    const { primaryTag } = this
    return `<a href="../lists/explorer.html#searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22contains%22%2C%22data%22%3A%22tags%22%2C%22origData%22%3A%22tags%22%2C%22type%22%3A%22string%22%2C%22value%22%3A%5B%22${primaryTag}%22%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D">${this.primaryTagName}</a>`
  }

  getPrimary(key) {
    const hits = this.getAll(key)
    if (hits.length >= 1) return hits[0]
  }

  get descriptionSection() {
    let description = ""
    const authoredDescription = this.get("description")
    const wikipediaSummary = this.get("wikipedia summary")
    const ghDescription = this.get("githubRepo description")
    const wpLink = this.get(`wikipedia`)
    if (wikipediaSummary)
      description =
        wikipediaSummary.split(". ").slice(0, 3).join(". ") +
        `. Read more on Wikipedia...\n ${wpLink} Read more on Wikipedia...`
    else if (authoredDescription) description = authoredDescription
    else if (ghDescription) description = ghDescription
    return `* ${description}`
  }

  get factsArray() {
    const { title, website } = this

    const facts = []
    const tags = this.get(PLDBKeywords.tags).split(" ")
    facts.push(
      `Tags: ` +
        tags
          .map(
            tag =>
              `<a href='../lists/explorer.html#searchBuilder=%7B"criteria"%3A%5B%7B"condition"%3A"contains"%2C"data"%3A"tags"%2C"origData"%3A"tags"%2C"type"%3A"string"%2C"value"%3A%5B"${tag}"%5D%7D%5D%2C"logic"%3A"AND"%7D'>${
                tagNames[tag] || tag
              }</a>`
          )
          .join(", ")
    )

    let interviews = this.get("interviews")
    if (interviews) {
      interviews = interviews.split(" ")
      facts.push(
        `Interview${interviews.length > 1 ? "s" : ""} with the creator${
          this.get("creators")?.includes(" and ") ? "s" : ""
        } of ${title}: ${linkManyAftertext(interviews)}`
      )
    }

    const githubRepo = this.particle.getParticle("githubRepo")
    if (githubRepo) {
      const stars = githubRepo.get("stars")
      const starMessage = stars ? ` and has ${numeral(stars).format("0,0")} stars` : ""
      facts.push(`${title} is developed on <a href="${githubRepo.getAtom(1)}">GitHub</a>${starMessage}`)
    }

    const gource = this.get("gource")
    if (gource) facts.push(`Watch the history of <a href="${gource}">the ${title} repo visualized with Gource</a>`)

    const gitlabRepo = this.get("gitlabRepo")
    if (gitlabRepo) facts.push(`${title} on GitLab\n ${gitlabRepo}`)

    const githubRepoCount = this.get("githubLanguage repos")
    if (githubRepoCount) {
      const url = `https://github.com/search?q=language:${this.get("githubLanguage")}`
      const repoCount = numeral(githubRepoCount).format("0,0")
      facts.push(`There are at least ${repoCount} ${title} repos on <a href="${url}">GitHub</a>`)
    }

    const supersetOf = this.getRelationshipFile("supersetOf")
    if (supersetOf)
      facts.push(
        `${title} is a <a href="../lists/explorer.html#columns=rank~id~appeared~tags~creators~supersetOf&searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22!null%22%2C%22data%22%3A%22supersetOf%22%2C%22origData%22%3A%22supersetOf%22%2C%22tags%22%3A%22html%22%2C%22value%22%3A%5B%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D">superset</a> of ${supersetOf.link()}`
      )

    const implementationOf = this.getRelationshipFile("implementationOf")
    if (implementationOf) facts.push(`${title} is an implementation of ${implementationOf.link()}`)

    const { lab } = this
    let labStr = ""
    if (lab.length) {
      labStr = lab.map(name => `<a href="../lists/labs.html#q=${name}">${name}</a>`).join(" and ")
      facts.push(`Early development of ${title} happened in ${labStr}`)
    }

    const influencedBy = this.get("influencedBy")
    if (influencedBy)
      facts.push(
        influencedBy
          .split(" ")
          .map(link => this.makeATag(link))
          .join(" and ") +
          " influenced the design of " +
          title
      )

    const { numberOfJobsEstimate } = this
    const jobs = numberOfJobsEstimate > 10 ? numeral(numberOfJobsEstimate).format("0a") : ""
    if (jobs) facts.push(`PLDB estimates there are currently ${jobs} job openings for ${title} programmers.`)

    const { extensions } = this
    if (extensions) facts.push(`file extensions for ${title} include ${toCommaList(extensions.split(" "))}`)

    const compilesTo = this.get("compilesTo")
    if (compilesTo)
      facts.push(
        `${title} compiles to ${compilesTo
          .split(" ")
          .map(link => this.makeATag(link))
          .join(" or ")}`
      )

    const writtenIn = this.get("writtenIn")
    if (writtenIn)
      facts.push(
        `${title} is written in ${writtenIn
          .split(" ")
          .map(link => this.makeATag(link))
          .join(", ")}`
      )

    const conferences = this.particle.getParticlesByGlobPath("conference")
    if (conferences.length) {
      facts.push(
        `Recurring conference about ${title}: ${conferences.map(
          particle => `<a href="${particle.getAtom(1)}">${particle.getAtomsFrom(2)}</a>`
        )}`
      )
    }

    const githubBigQuery = this.particle.getParticle("githubBigQuery")
    if (githubBigQuery) {
      const url = `https://api.github.com/search/repositories?q=language:${githubBigQuery.content}`
      const userCount = numeral(githubBigQuery.get("users")).format("0a")
      const repoCount = numeral(githubBigQuery.get("repos")).format("0a")
      facts.push(
        `The  Google BigQuery Public Dataset GitHub snapshot shows ${userCount} users using ${title} in ${repoCount} repos on <a href="${url}">GitHub</a>`
      )
    }

    const meetup = this.get("meetup")
    if (meetup) {
      const groupCount = numeral(this.get("meetup groupCount")).format("0,0")
      facts.push(`Check out the ${groupCount} <a href="${meetup}/">${title} meetup groups</a> on Meetup.com.`)
    }

    const paper = this.get("paper")
    if (paper) facts.push(`<a href="${paper}">First announcement of</a> ${title}`)

    const subreddit = this.get("subreddit")
    if (subreddit) {
      const peNum = numeral(this.getMostRecentInt("subreddit memberCount")).format("0,0")
      facts.push(`There are ${peNum} members in the <a href="${subreddit}">${title} subreddit</a>`)
    }

    const pe = this.get("projectEuler")
    if (pe) {
      const peNum = numeral(this.getMostRecentInt("projectEuler memberCount")).format("0,0")
      facts.push(
        `There are ${peNum} <a href="https://projecteuler.net/language=${pe}">Project Euler</a> users using ${title}`
      )
    }

    const soSurvey = this.particle.getParticle("stackOverflowSurvey 2021")
    if (soSurvey) {
      let fact = `In the 2021 StackOverflow <a href="https://insights.stackoverflow.com/survey">developer survey</a> ${title} programmers reported a median salary of $${numeral(
        soSurvey.get("medianSalary")
      ).format("0,0")}. `

      fact += `${lodash.round(
        parseFloat(soSurvey.get("percentageUsing")) * 100,
        2
      )}% of respondents reported using ${title}. `

      fact += `${numeral(soSurvey.get("users")).format("0,0")} programmers reported using ${title}, and ${numeral(
        soSurvey.get("fans")
      ).format("0,0")} said they wanted to use it`

      facts.push(fact)
    }

    const rosettaCode = this.get("rosettaCode")
    if (rosettaCode) facts.push(`Explore ${title} snippets on <a href="${rosettaCode}">Rosetta Code</a>`)

    const nativeLanguage = this.get("nativeLanguage")
    if (nativeLanguage) facts.push(`${title} is written with the native language of ${nativeLanguage}`)

    const gdb = this.get("gdbSupport")
    if (gdb) facts.push(`${title} is supported by the <a href="https://www.sourceware.org/gdb/">GDB</a>`)

    const hopl = this.get("hopl")
    if (hopl) facts.push(`${title} on HOPL\n ${hopl}`)

    const tiobe = this.get("tiobe")
    const tiobeRank = this.get("tiobe currentRank")
    if (tiobeRank)
      facts.push(`${title} ranks #${tiobeRank} in the <a href="https://www.tiobe.com/tiobe-index/">TIOBE Index</a>`)
    else if (tiobe) facts.push(`${title} appears in the <a href="https://www.tiobe.com/tiobe-index/">TIOBE Index</a>`)

    const esolang = this.get("esolang")
    if (esolang) facts.push(`${title} on Esolang\n ${esolang}`)

    const ubuntu = this.get("ubuntuPackage")
    if (ubuntu) facts.push(`${title} Ubuntu package\n https://packages.ubuntu.com/jammy/${ubuntu}`)

    const antlr = this.get("antlr")
    if (antlr) facts.push(`<a href="antlr.html">ANTLR</a> <a href="${antlr}">grammar</a> for ${title}`)

    // todo: handle multiple
    const lsp = this.get("languageServerProtocolProject")
    if (lsp) facts.push(`${title} <a href="language-server-protocol.html">LSP</a> <a href="${lsp}">implementation</a>`)

    const codeMirror = this.get("codeMirror")
    if (codeMirror)
      facts.push(
        `<a href="codemirror.html">CodeMirror</a> <a href="https://github.com/codemirror/codemirror5/tree/master/mode/${codeMirror}">package</a> for syntax highlighting ${title}`
      )

    const monaco = this.get("monaco")
    if (monaco)
      facts.push(
        `<a href="monaco.html">Monaco</a> <a href="https://github.com/microsoft/monaco-editor/tree/main/src/basic-languages/${monaco}">package</a> for syntax highlighting ${title}`
      )

    const pygmentsHighlighter = this.get("pygmentsHighlighter")
    if (pygmentsHighlighter)
      facts.push(
        `<a href="pygments.html">Pygments</a> supports <a href="https://github.com/pygments/pygments/blob/master/pygments/lexers/${this.get(
          "pygmentsHighlighter filename"
        )}">syntax highlighting</a> for ${title}`
      )

    const linguist = this.get("linguistGrammarRepo")
    if (linguist)
      facts.push(
        `GitHub supports <a href="${linguist}" title="The package used for syntax highlighting by GitHub Linguist.">syntax highlighting</a> for ${title}`
      )

    const quineRelay = this.get("quineRelay")
    if (quineRelay)
      facts.push(`${title} appears in the <a href="https://github.com/mame/quine-relay">Quine Relay</a> project`)

    const exercism = this.get("exercism")
    if (exercism) facts.push(`Learn <a href="${exercism}">${title} on exercism.</a>`)

    const jupyters = this.getAll("jupyterKernel")
    if (jupyters.length === 1)
      facts.push(
        `There is 1 <a href="jupyter-notebook.html">Jupyter</a> <a href="${jupyters[0]}">Kernel</a> for ${title}`
      )
    else if (jupyters.length > 1)
      facts.push(
        `PLDB has ${jupyters.length} <a href="jupyter-notebook.html">Jupyter</a> Kernels for ${title}: ${jupyters
          .map(makePrettyUrlLink)
          .join(", ")}`
      )

    const packageRepos = this.getAll("packageRepository")
    if (packageRepos.length === 1)
      facts.push(`There is a <a href="${packageRepos[0]}">central package repository</a> for ${title}`)
    else if (packageRepos.length > 1)
      facts.push(
        `There are ${packageRepos.length} central package repositories for ${title}: ${linkManyAftertext(packageRepos)}`
      )

    const annualReport = this.getAll("annualReportsUrl")

    if (annualReport.length >= 1) facts.push(`Annual Reports for ${title}\n ${annualReport[0]}`)

    const eventsPage = this.getAll("eventsPageUrl")

    if (eventsPage.length >= 1) facts.push(`Events page for ${title}\n ${eventsPage[0]}`)

    const indeedJobs = this.particle.getParticle("indeedJobs")
    if (indeedJobs) {
      const query = this.get("indeedJobs")
      if (query) {
        const jobCount = numeral(this.getMostRecentInt("indeedJobs")).format("0,0")
        facts.push(
          `Indeed.com has ${jobCount} matches for <a href="https://www.indeed.com/jobs?q=${query}">"${query}"</a>.`
        )
      }
    }

    const domainRegistered = this.get("domainName registered")
    if (domainRegistered)
      facts.push(`<a href="${website}">${this.get("domainName")}</a> was registered in ${domainRegistered}`)

    const wpRelated = this.get("wikipedia related")
    const seeAlsoLinks = wpRelated ? wpRelated.split(" ") : []
    const related = this.get("related")
    if (related) related.split(" ").forEach(id => seeAlsoLinks.push(id))

    if (seeAlsoLinks.length)
      facts.push(
        "See also: " +
          `(${seeAlsoLinks.length} related languages) ` +
          seeAlsoLinks.map(link => this.makeATag(link)).join(", ")
      )

    const { otherReferences } = this

    const semanticScholarReferences = otherReferences.filter(link => link.includes("semanticscholar"))
    const nonSemanticScholarReferences = otherReferences.filter(link => !link.includes("semanticscholar"))

    if (semanticScholarReferences.length)
      facts.push(`Read more about ${title} on Semantic Scholar: ${linkManyAftertext(semanticScholarReferences)}`)
    if (nonSemanticScholarReferences.length)
      facts.push(`Read more about ${title} on the web: ${linkManyAftertext(nonSemanticScholarReferences)}`)

    if (this.parsed.inboundLinks) {
      const inboundLinks = lodash.uniq(this.parsed.inboundLinks.split(" "))
      facts.push(
        `${inboundLinks.length} PLDB concepts link to ${title}: ` +
          inboundLinks.map(link => this.makeATag(link)).join(", ")
      )
    }

    return facts
  }

  get keywordsSection() {
    const keywords = this.get("keywords")
    if (!keywords) return ""
    return `<div class="keywordsBlock">
codeWithHeader ${this.name} <a href="../lists/keywords.html#q=${this.id}">Keywords</a>
 ${keywords}
</div>`
  }

  get funFactSection() {
    return this.particle
      .findParticles("funFact")
      .map(
        fact =>
          `codeWithHeader ${`<a href='${fact.content}'>Fun fact</a>`}:
 ${cleanAndRightShift(lodash.escape(fact.subparticlesToString()))}`
      )
      .join("\n\n")
  }

  get exampleSection() {
    return this.allExamples
      .map(
        example =>
          `codeWithHeader Example from ${
            !example.link ? example.source : `<a href='${example.link}'>` + example.source + "</a>"
          }:
 ${cleanAndRightShift(lodash.escape(example.code))}`
      )
      .join("\n\n")
  }

  get kpiBar() {
    const { appeared, title, rank } = this
    const numberOfRepos = this.get("githubLanguage repos")

    const lines = [
      `#${this.rank} on PLDB`,
      appeared ? `${currentYear - appeared} Years Old` : "",
      numberOfRepos ? `${numeral(numberOfRepos).format("0a")} <span title="${title} repos on GitHub.">Repos</span>` : ""
    ]
      .filter(i => i)
      .join("\n ")

    return `dashboard
 ${lines}`
  }
}

// One feature maps to one Parser that extends abstractFeatureParser
class Feature {
  constructor(measure, tables) {
    this.measure = measure
    this.fileName = "measures.parsers"
    this.id = measure.Name
    this.tables = tables
  }

  id = ""
  fileName = ""

  get permalink() {
    return this.id + ".html"
  }

  get yes() {
    return this.languagesWithThisFeature.length
  }

  get no() {
    return this.languagesWithoutThisFeature.length
  }

  get percentage() {
    const { yes, no } = this
    const measurements = yes + no
    return measurements < 20 ? "-" : lodash.round((100 * yes) / measurements, 0) + "%"
  }

  get aka() {
    return this.get("aka") // .join(" or "),
  }

  get token() {
    return this.get("tokenKeyword")
  }

  get titleLink() {
    return `../features/${this.permalink}`
  }

  get(Atom) {
    // todo; fix this
    // return this.measure[Atom]
    return this.particle.getFrom(`string ${Atom}`)
  }

  get particle() {
    return ParserFile.getParticle(this.id + "Parser")
  }

  get title() {
    return this.get("title") || this.id
  }

  get pseudoExample() {
    return (this.get("pseudoExample") || "").replace(/\</g, "&lt;").replace(/\|/g, "&#124;")
  }

  get references() {
    return (this.get("reference") || "").split(" ").filter(i => i)
  }

  get languagesWithThisFeature() {
    const { id } = this
    return this.getLanguagesWithFeatureResearched(id).filter(file => file[id])
  }

  get languagesWithoutThisFeature() {
    const { id } = this
    return this.getLanguagesWithFeatureResearched(id).filter(file => !file[id])
  }

  getLanguagesWithFeatureResearched(id) {
    if (!this.tables.featureCache) this.tables.featureCache = {}
    if (this.tables.featureCache[id]) return this.tables.featureCache[id]
    // todo: re-add support for "extended"
    this.tables.featureCache[id] = this.tables.pldb.filter(file => file[id] !== "" && file[id] !== undefined)
    return this.tables.featureCache[id]
  }

  get summary() {
    const { id, title, fileName, titleLink, aka, token, yes, no, percentage, pseudoExample } = this
    return {
      id,
      title,
      fileName,
      titleLink,
      aka,
      token,
      yes,
      no,
      measurements: yes + no,
      percentage,
      pseudoExample
    }
  }

  toScroll() {
    const { title, id, fileName, references, previous, next } = this

    const positives = this.languagesWithThisFeature
    const positiveText = `* Languages *with* ${title} include ${positives
      .map(file => `<a href="../concepts/${file.id}.html">${file.name}</a>`)
      .join(", ")}`

    const negatives = this.languagesWithoutThisFeature
    const negativeText = negatives.length
      ? `* Languages *without* ${title} include ${negatives
          .map(file => `<a href="../concepts/${file.id}.html">${file.name}</a>`)
          .join(", ")}`
      : ""

    const examples = positives
      .filter(file => this.tables.getConceptFile(file.id).getParticle(id).length)
      .map(file => {
        return {
          id: file.id,
          name: file.name,
          example: this.tables.getConceptFile(file.id).getParticle(id).subparticlesToString()
        }
      })
    const grouped = lodash.groupBy(examples, "example")
    const examplesText = Object.values(grouped)
      .map(group => {
        const links = group.map(hit => `<a href="../concepts/${hit.id}.html">${hit.name}</a>`)

        return `codeWithHeader Example from <b>${links.length} languages</b>: ${links.join(", ")}
 ${shiftRight(removeReturnChars(lodash.escape(group[0].example)), 1)}`
      })
      .join("\n\n")

    let referencesText = ""
    if (references.length) referencesText = `* Read more about ${title} on the web: ${linkManyAftertext(references)}`

    const filledLink = `../lists/explorer.html#columns=rank~id~appeared~tags~creators~${id}&searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22!null%22%2C%22data%22%3A%22${id}%22%2C%22origData%22%3A%22${id}%22%2C%22type%22%3A%22num%22%2C%22value%22%3A%5B%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D`
    const missingLink = `../lists/explorer.html#columns=rank~id~appeared~tags~creators~${id}&searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22null%22%2C%22data%22%3A%22${id}%22%2C%22origData%22%3A%22${id}%22%2C%22type%22%3A%22num%22%2C%22value%22%3A%5B%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D`

    const explorerLinks = `View all concepts with or missing a *${id}* measurement
 link ${missingLink} missing
 link ${filledLink} with
`

    let descriptionText = ""
    const description = this.measure.Description
    if (description) descriptionText = `* This question asks: ${description}`

    return `header.scroll

title ${title} - language feature
tags Feature
printTitle ${title}

<a class="trueBaseThemePreviousItem" href="${previous.permalink}">&lt;</a>
<a class="trueBaseThemeNextItem" href="${next.permalink}">&gt;</a>

editUrl https://github.com/breck7/pldb/blob/main/Computer.js

container 600px

${examplesText}

***

${[positiveText, negativeText, descriptionText, explorerLinks, referencesText].filter(i => i).join("\n\n***\n\n")}

keyboardNav ${previous.permalink} ${next.permalink}

../footer.scroll
`.replace(/\n\n\n+/g, "\n\n")
  }
}

const getMostRecentInt = (concept, pathToSet) => {
  let set = concept.getParticle(pathToSet)
  if (!set) return 0
  set = set.toObject()
  const key = Math.max(...Object.keys(set).map(year => parseInt(year)))
  return parseInt(set[key])
}

const getJoined = (row, keywords) => {
  const Atoms = keywords
    .map(Atom => row[Atom] || "")
    .filter(i => i)
    .join(" ")
    .split(" ")
  return lodash.uniq(Atoms).join(" ")
}

const groupByListValues = (listColumnName, rows, delimiter = " && ") => {
  const values = {}
  rows.forEach(row => {
    const value = row[listColumnName]
    if (!value) return
    value.split(delimiter).forEach(value => {
      if (!values[value]) values[value] = []
      values[value].push(row)
    })
  })
  return values
}

class Tables {
  constructor() {
    this.quickCache = {}
  }

  get top1000() {
    return this.toTable(this.top.slice(0, 1000))
  }

  get TOTAL() {
    return numeral(this.top.length).format("0,0")
  }

  get all() {
    return this.toTable(this.top)
  }

  _cache = {}
  getConceptFile(id) {
    if (!this._cache[id]) this._cache[id] = new Particle(Disk.read(path.join(__dirname, "concepts", id + ".scroll")))
    return this._cache[id]
  }

  toTable(data) {
    const cols = lodash.keys(data[0])
    const rows = lodash.map(data, row => cols.map(col => row[col]).join(","))
    const tsv = [cols.join(","), ...rows].join("\n  ")
    return "datatable\n delimiter ,\n printTable\n data\n  " + tsv
  }

  _top
  get top() {
    if (this._top) return this._top
    const { pldb } = this
    this._top = lodash
      .chain(pldb)
      .map(row =>
        lodash.pick(row, [
          "id",
          "name",
          "rank",
          "appeared",
          "tags",
          "creators",
          "foundationScore",
          "inboundLinksCount",
          "measurements"
        ])
      )
      .value()
      .map(row => {
        row.nameLink = "../concepts/" + row.id + ".html"
        delete row.id
        return row
      })
    return this._top
  }

  get pldb() {
    return require("./pldb.json")
  }

  _getFileAtRank(rank, ranks) {
    rank = rank - 1
    const count = Object.keys(ranks).length
    if (rank < 0) rank = count - 1
    if (rank >= count) rank = 0
    return this.getConceptPage(ranks[rank].id)
  }

  getFileAtRank(rank) {
    return this._getFileAtRank(rank, this.pldb)
  }

  initConceptPages() {
    if (this._conceptPageCache) return
    this._conceptPageCache = {}
    this._conceptPages = []
    this.pldb.forEach(file => {
      const page = new ConceptPage(file, this)
      this._conceptPageCache[file.id] = page
      this._conceptPages.push(page)
    })
    console.log(`Computer.js loaded ${this.pldb.length} langs from pldb.json`)
  }

  getConceptPage(id) {
    this.initConceptPages()
    return this._conceptPageCache[id]
  }

  getLanguageTemplate(absolutePath) {
    if (absolutePath.endsWith("conceptPage.scroll")) return ""
    const name = path.basename(absolutePath).replace(".scroll", "")
    try {
      return this.getConceptPage(name).toScroll()
    } catch (err) {
      console.error(err)
      console.error(`Error loading '${name}' in '${absolutePath}'`)
      return ""
    }
  }

  get measures() {
    return require("./measures.json")
  }

  get featuresMap() {
    if (this.quickCache.featuresMap) return this.quickCache.featuresMap
    this.quickCache.featuresMap = new Map()
    const featuresMap = this.quickCache.featuresMap
    this.features.forEach(feature => featuresMap.set(feature.id, feature))
    return featuresMap
  }

  get features() {
    const features = this.measures
      .filter(measure => measure.SortIndex === 7)
      .map(measure => {
        const feature = new Feature(measure, this)
        if (!feature.title) {
          throw new Error(`Feature ${measure} has no title.`)
        }
        return feature
      })

    let previous = features[features.length - 1]
    features.forEach((feature, index) => {
      feature.previous = previous
      feature.next = features[index + 1]
      previous = feature
    })
    features[features.length - 1].next = features[0]

    return features
  }

  getFeaturesImports(limit = 0) {
    const { features } = this
    const topFeatures = lodash.sortBy(features, "yes")
    topFeatures.reverse()
    const summaries = topFeatures.map(feature => feature.summary).filter(feature => feature.measurements >= limit)
    return {
      COUNT: numeral(summaries.length).format("0,0"),
      TABLE: quickTable(summaries, ["title", "titleLink", "pseudoExample", "yes", "no", "percentage"])
    }
  }

  get topFeaturesImports() {
    return this.getFeaturesImports(10)
  }

  get allFeaturesImports() {
    return this.getFeaturesImports(0)
  }

  writeAllFeaturePages() {
    this.features.forEach(feature => {
      Disk.write(path.join(__dirname, "features", feature.id + ".scroll"), feature.toScroll())
    })
  }

  get creators() {
    return require(path.join(__dirname, "creators", "creators.json"))
  }

  get creatorsTable() {
    const entities = groupByListValues("creators", this.pldb, " and ")
    const { creators } = this
    const creatorsMap = {}
    creators.forEach(creator => (creatorsMap[creator.name] = creator))

    const rows = Object.keys(entities).map(name => {
      const group = lodash.sortBy(entities[name], "rank")
      const person = creatorsMap[name] || {}
      const anchorTag = lodash.camelCase(name)

      const links = {
        git: person.gits,
        home: person.homepage,
        twitter: person.twitter,
        wikipedia: person.wikipedia,
        self_improvement: person.interview
      }
      const linksCol = Object.keys(links)
        .filter(key => links[key])
        .map(key =>
          SVGS[key]
            ? `<a href="${links[key]}">${SVGS[key]}</a>`
            : `<a href="${links[key]}" class="material-symbols-outlined">${key}</a>`
        )
        .join(" ")

      return {
        name: `<a href="${person.primaryLink || ""}" name='${anchorTag}' />${name}`,
        links: `<span class="creatorQuickLinks">${linksCol}</span>`,
        born: person.born,
        country: person.country,
        creations: group.map(file => `<a href='../concepts/${file.id}.html'>${file.name}</a>`).join(" - "),
        count: group.length,
        topRank: group[0].rank
      }
    })

    const birthYears = rows.map(row => row.born).filter(i => i)
    birthYears.sort()

    const minYear = 1906 // Math.min(...birthYears)
    const maxYear = 2024
    const histogram = Array.from(
      { length: maxYear - minYear + 1 },
      (_, i) => birthYears.filter(year => year === minYear + i).length
    )

    // SPARKDATA

    return {
      SPARKDATA: histogram.join(" "),
      TABLE: quickTable(lodash.sortBy(rows, "topRank"), [
        "name",
        "links",
        "born",
        "country",
        "creations",
        "count",
        "topRank"
      ]),
      COUNT: numeral(Object.values(entities).length).format("0,0")
    }
  }

  get extensions() {
    const files = this.pldb
      .map(row => {
        row.extensions = getJoined(row, [
          "fileExtensions",
          "clocExtensions",
          "githubLanguage_fileExtensions",
          "pygmentsHighlighter_fileExtensions",
          "wikipedia_fileExtensions"
        ])
        return row
      })
      .filter(file => file.extensions)
      .map(file => {
        return {
          name: file.name,
          nameLink: `../concepts/${file.id}.html`,
          rank: file.rank,
          extensions: file.extensions
        }
      })

    const allExtensions = new Set()
    files.forEach(file => file.extensions.split(" ").forEach(ext => allExtensions.add(ext)))

    files.forEach(file => (file.numberOfExtensions = file.extensions.split(" ").length))

    return {
      EXTENSION_COUNT: numeral(allExtensions.size).format("0,0"),
      TABLE: quickTable(lodash.sortBy(files, "rank"), ["name", "nameLink", "extensions", "numberOfExtensions"]),
      LANG_WITH_DATA_COUNT: files.length
    }
  }

  get labs() {
    const files = lodash.sortBy(
      this.pldb.filter(file => file.lab?.length),
      "rank"
    )

    const entities = groupByListValues("lab", files)
    const rows = Object.keys(entities).map(name => {
      const group = entities[name]
      const languages = group.map(lang => `<a href='../concepts/${lang.id}.html'>${lang.name}</a>`).join(" - ")
      const count = group.length
      const top = Math.min(...group.map(lang => lang.rank))

      const wrappedName = `<a href="explorer.html#columns=rank~name~id~appeared~tags~creators~lab&searchBuilder=%7B%22criteria%22%3A%5B%7B%22condition%22%3A%22contains%22%2C%22data%22%3A%22lab%22%2C%22origData%22%3A%22lab%22%2C%22type%22%3A%22string%22%2C%22value%22%3A%5B%22${name}%22%5D%7D%5D%2C%22logic%22%3A%22AND%22%7D" name='${lodash.camelCase(
        name
      )}' />${name}`

      return { name: wrappedName, languages, count, top }
    })
    const sorted = lodash.orderBy(rows, ["count", "top"], ["desc", "asc"])
    return {
      TABLE: quickTable(sorted, ["count", "top", "name", "languages"]),
      COUNT: numeral(Object.values(entities).length).format("0,0")
    }
  }

  get autocompleteJs() {
    const json = JSON.stringify(
      this.pldb.map(file => {
        const { id } = file
        return {
          label: file.name,
          id,
          url: `/concepts/${id}.html`
        }
      }),
      undefined,
      2
    )
    const js =
      Disk.read(path.join(__dirname, "code", "browser", "autocompleter.js")) +
      "\n" +
      `var autocompleteJs = ` +
      json +
      "\n\n" +
      Disk.read(path.join(__dirname, "code", "browser", "client.js"))
    return `script\n ` + js.replace(/\n/g, "\n ")
  }

  get keywordsImports() {
    const { rows, langsWithKeywordsCount } = this.keywordsTable

    return {
      NUM_KEYWORDS: numeral(rows.length).format("0,0"),
      LANGS_WITH_KEYWORD_DATA: langsWithKeywordsCount,
      KEYWORDS_TABLE: quickTable(rows, ["keyword", "count", "frequency", "langs"])
    }
  }

  get keywordsTable() {
    if (this.quickCache.keywordsTable) return this.quickCache.keywordsTable
    this.initConceptPages()
    const langsWithKeywords = this._conceptPages.filter(file => file.particle.has("keywords"))
    const langsWithKeywordsCount = langsWithKeywords.length

    const keywordsMap = {}
    langsWithKeywords.forEach(file => {
      file.keywords.forEach(keyword => {
        const keywordKey = "Q" + keyword // b.c. you cannot have a key "constructor" in JS objects.

        if (!keywordsMap[keywordKey])
          keywordsMap[keywordKey] = {
            keyword,
            ids: []
          }

        const row = keywordsMap[keywordKey]

        row.ids.push(file.id)
      })
    })

    const rows = Object.values(keywordsMap)
    rows.forEach(row => {
      row.count = row.ids.length
      row.langs = row.ids
        .map(id => {
          const file = this.getConceptPage(id)
          return `<a href='../concepts/${file.id}.html'>${file.name}</a>`
        })
        .join(" ")
      row.frequency = Math.round(100 * lodash.round(row.count / langsWithKeywordsCount, 2)) + "%"
    })

    this.quickCache.keywordsTable = {
      langsWithKeywordsCount,
      rows: lodash.sortBy(rows, "count").reverse()
    }

    return this.quickCache.keywordsTable
  }
}

const computeds = {
  numberOfUsersEstimate(concept) {
    const mostRecents = ["linkedInSkill", "subreddit memberCount", "projectEuler members"]
    const directs = ["meetup members", "githubRepo stars", "repoStats committers"]
    const customs = {
      wikipedia: v => 20,
      packageRepository: v => 1000, // todo: pull author number
      "wikipedia dailyPageViews": count => 100 * (parseInt(count) / 20), // say its 95% bot traffic, and 1% of users visit the wp page daily
      linguistGrammarRepo: c => 200, // According to https://github.com/github/linguist/blob/master/CONTRIBUTING.md, linguist indicates a min of 200 users.
      codeMirror: v => 50,
      website: v => 1,
      githubRepo: v => 1,
      "githubRepo forks": v => v * 3,
      annualReport: v => 1000
    }

    return Math.round(
      lodash.sum(mostRecents.map(key => getMostRecentInt(concept, key))) +
        lodash.sum(directs.map(key => parseInt(concept.get(key) || 0))) +
        lodash.sum(
          Object.keys(customs).map(key => {
            const val = concept.get(key)
            return val ? customs[key](val) : 0
          })
        )
    )
  },

  numberOfJobsEstimate(concept) {
    return Math.round(getMostRecentInt(concept, "linkedInSkill") * 0.01) + getMostRecentInt(concept, "indeedJobs")
  },

  exampleCount(concept) {
    return concept.topDownArray.filter(particle => particle.isExampleCode).length
  },

  score(concept) {},

  numberOfCreators(concept) {
    const creators = concept.get("creators")
    return creators ? creators.split(" and ").length : ""
  },

  measurements(concept) {
    let count = 0
    concept.forEach(particle => {
      if (particle.isMeasure) count++
    })
    return count
  },

  expandedMeasurements(concept) {
    let count = 0
    concept.forEach(particle => {
      if (!particle.isMeasure) return
      if (particle.listDelimiter !== undefined) count += particle.getLine().split(particle.listDelimiter).length
      else count++
    })
    return count
  },

  bookCount(concept) {
    const gr = concept.getParticle(`goodreads`)?.length
    const isbndb = concept.getParticle(`isbndb`)?.length
    let count = 0
    if (gr) count += gr - 1
    if (isbndb) count += isbndb - 1
    return count
  },

  paperCount(concept) {
    const ss = concept.getParticle(`semanticScholar`)?.length
    let count = 0
    if (ss) count += ss - 1
    return count
  },

  isFinished(concept) {
    return concept.get("isFinished") ?? this.lastActivity(concept) < 2014
  },

  isOpenSource(concept, computer) {
    return concept.get("isOpenSource") ?? (computeds.mainRepo(concept) ? true : "") // if it has a mainRepo then it must be open source.
  },

  mainRepo(concept) {
    const repo = concept.getOneOf("gitRepo githubRepo gitlabRepo sourcehutRepo".split(" "))
    return repo || ""
  },

  writtenInCount(concept) {
    return concept.has("writtenIn") ? concept.get("writtenIn").split(" ").length : ""
  },

  latestMajorVersion(concept) {
    let version = concept.get("latestVersion")
    if (!version) return ""
    version = version.replace(/[^0-9\.]/g, "")
    version = version.split(".")[0]
    return parseInt(version)
  },

  usesSemanticVersioning(concept) {
    if (concept.has("usesSemanticVersioning")) return concept.get("usesSemanticVersioning") === "true"
    const version = computeds.latestMajorVersion(concept)
    if (version === "") return ""
    return version > 999 ? false : true // dont include it if it uses a year as aversion, like 2024
  },

  isSelfHosted(concept) {
    const writtenIn = concept.get("writtenIn")
    return writtenIn ? writtenIn.includes(concept.get("id")) : ""
  },

  hoplId(concept) {
    const id = concept.get("hopl")?.replace("https://hopl.info/showlanguage.prx?exp=", "")
    return id === undefined ? "" : parseInt(id)
  },

  lastActivity(concept) {
    return lodash.max(concept.findAllAtomsWithAtomType("yearAtom").map(Atom => parseInt(Atom.Atom)))
  },

  isLanguage(concept) {
    if (!concept.get(PLDBKeywords.tags)) throw new Error(`${concept.get("id")} needs tags`) // todo: why isnt this throwing on check?
    return isLanguage(concept.get(PLDBKeywords.tags).split(" ")[0])
  },

  rank(concept, computer) {
    return computer.ranks[concept.get("id")].index
  },

  pldbScore(concept, computer) {
    return computer.ranks[concept.get("id")].pldbScore
  },

  inboundLinks(concept, computer) {
    return computer.inboundLinks[concept.get("id")].join(" ") // todo: keep as array
  },

  inboundLinksCount(concept, computer) {
    return computer.inboundLinks[concept.get("id")].length
  },

  foundationScore(concept, computer) {
    return computer.writtenIn[concept.get("id")].length
  }
}

class MeasureComputer {
  constructor(concepts) {
    this.quickCache = {}
    this.concepts = concepts
    this.writtenIn = this.makeWrittenInCache()
    this.inboundLinks = this.makeInboundLinksCache()
    this.ranks = calcRanks(this)
    Disk.write(path.join(__dirname, "ranks.json"), JSON.stringify(this.ranks, null, 2))
  }

  makeWrittenInCache() {
    const writtenInCache = {}
    this.concepts.forEach(concept => {
      writtenInCache[concept.get("id")] = []
    })
    this.concepts.forEach(concept => {
      const conceptId = concept.get("id")
      const writtenIn = concept.get("writtenIn")
      if (!writtenIn) return
      writtenIn.split(" ").forEach(id => writtenInCache[id].push(conceptId))
    })
    return writtenInCache
  }

  makeInboundLinksCache() {
    const inboundLinks = {}
    this.concepts.forEach(concept => {
      inboundLinks[concept.get("id")] = []
    })

    this.concepts.forEach(concept => {
      const id = concept.get("id")
      concept
        .filter(particle => particle.isLinks)
        .forEach(particle => {
          const links = particle.content.split(" ")
          links.forEach(link => {
            if (!inboundLinks[link]) throw new Error(`No file "${link}" found in "${id}"`)

            inboundLinks[link].push(id)
          })
        })
    })

    return inboundLinks
  }

  get(measureName, concept) {
    if (computeds[measureName]) {
      if (!concept[measureName]) concept[measureName] = computeds[measureName](concept, this)
      return concept[measureName]
    }
    throw new Error(`${measureName} not found`)
  }
}

const calcRanks = computer => {
  const { concepts } = computer
  const categories = [
    "numberOfUsersEstimate",
    "foundationScore",
    "numberOfJobsEstimate",
    "inboundLinksCount",
    "measurements"
  ]

  let objects = concepts.map(concept => {
    const id = concept.get("id")
    const object = {}
    object.id = id
    categories.forEach(category => (object[category] = computer.get(category, concept)))

    return object
  })

  categories.forEach(category => (objects = rankSort(objects, category)))

  const conceptCount = objects.length

  objects.forEach(
    (obj, rank) => (obj.pldbScore = lodash.sum(categories.map(category => conceptCount - obj[category + "Rank"])))
  )
  objects = lodash.sortBy(objects, ["pldbScore"]).reverse()

  const ranks = {}
  objects.forEach((obj, index) => {
    obj.index = index + 1
    ranks[obj.id] = obj
  })
  return ranks
}

const rankSort = (objects, key) => {
  objects = lodash.sortBy(objects, [key])
  objects.reverse()
  let lastValue = objects[0][key]
  let lastRank = 0
  objects.forEach((obj, rank) => {
    const theValue = obj[key]
    if (lastValue === theValue) {
      // A tie
      obj[key + "Rank"] = lastRank
    } else {
      obj[key + "Rank"] = rank
      lastRank = rank
      lastValue = theValue
    }
  })
  return objects
}

module.exports = { MeasureComputer, Tables: new Tables() }