refact: rename 404 hint component

src/components/FourZeroFourHint/index.tsx

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+import { WindowLocation } from "@reach/router"
+import React, { FC, Fragment } from "react"
+import * as SC from "./styles"
+
+import { FileConnection } from "../../../generated/graphql"
+
+// helper function to make matrix generation easier
+// credits to https://stackoverflow.com/a/13808461
+function makeMatrix(w: number, h: number, val: any = null) {
+  return Array(h)
+    .fill(null)
+    .map(() => Array(w).fill(val))
+}
+
+// calculate semantic difference
+// based on one character edits
+// efficient refactoring inspired by MIT licensed repo:
+// https://github.com/trekhleb/javascript-algorithms
+function levenshteinDistance(term1: string, term2: string) {
+  /* base case: empty strings */
+  if (term1.length === 0) {
+    return term2.length
+  }
+  if (term2.length === 0) {
+    return term1.length
+  }
+
+  // this will be our comparison matrix
+  const matrix = makeMatrix(term1.length + 1, term2.length + 1, null)
+
+  // make zeroeth row based off first term
+  for (let i = 0; i <= term1.length; i += 1) {
+    matrix[0][i] = i
+  }
+
+  // make zeroeth column based off second term
+  for (let j = 0; j <= term2.length; j += 1) {
+    matrix[j][0] = j
+  }
+
+  // iterative with full matrix implementation
+  // https://en.wikipedia.org/wiki/Levenshtein_distance
+  for (let j = 1; j <= term2.length; j += 1) {
+    for (let i = 1; i <= term1.length; i += 1) {
+      const substitutionCost = term1[i - 1] === term2[j - 1] ? 0 : 1
+
+      matrix[j][i] = Math.min(
+        matrix[j - 1][i] + 1, // deletion
+        matrix[j][i - 1] + 1, // insertion
+        matrix[j - 1][i - 1] + substitutionCost
+      ) // substitution
+    }
+  }
+
+  return matrix[term2.length][term1.length]
+}
+
+interface IFourZeroFourHint {
+  basepath: string
+  location: WindowLocation
+  data: { allFile: FileConnection }
+  threshold?: number
+}
+
+export const FourZeroFourHint: FC<IFourZeroFourHint> = ({
+  basepath,
+  location,
+  data,
+  threshold = 8,
+}) => {
+  // the data prop has the graphql result
+  // we're abstracting it to `linkArray` to just have array of edges matched
+  // must use `.node.absolutePath` on each edge to get each node's absolute link
+  // we will compare this link
+  // however, the relative links are more user friendly
+  const linkArray = data.allFile.edges
+
+  // location prop has several attributes
+  // location.origin is base url
+  // location.href is the window location
+  // location.pathname is link after protocol and hostname
+  // by replacing `"/resources/"`,
+  // we are left with only the relative path to `resources`
+  const search = location.pathname.replace(`/${basepath}`, "")
+
+  // filter based on distance
+  // levenshtein distance of x means how 'off' it was
+  const displayArray = linkArray.filter((value) => {
+    return (
+      levenshteinDistance(
+        search.toLowerCase(),
+        value.node!.relativePath!.toLowerCase()
+      ) < threshold
+    )
+  })
+
+  // helpful message if no matches found
+  const found = displayArray.length === 0 && "Oops, nothing similar found."
+
+  return (
+    <Fragment>
+      <SC.StyledDiv>
+        <h3>Based off of "{search}" you may have meant:</h3>
+        {found}
+      </SC.StyledDiv>
+      <ul>
+        {displayArray.map((value, index) => {
+          return (
+            <li key={index}>
+              <SC.StyledLink to={`${basepath}${value.node.relativePath}`}>
+                {value.node.relativePath}
+              </SC.StyledLink>
+            </li>
+          )
+        })}
+      </ul>
+    </Fragment>
+  )
+}

src/components/FourZeroFourHint/styles.tsx

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+import { Link } from "gatsby"
+import styled from "styled-components"
+
+export const StyledLink = styled(Link)`
+  color: #0090d8;
+  font-weight: 700;
+  border-bottom: 2px solid;
+  text-decoration: none;
+  transition: color 0.3s;
+
+  &:hover,
+  &:focus {
+    color: #5dbbea;
+    transition: none;
+  }
+`
+
+export const StyledDiv = styled.div`
+  width: 100%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  flex-direction: column;
+`