Add search suggestions

src/application-globals.rkt

@@ -1,5 +1,6 @@
 #lang racket/base
 (require racket/string
+         json
          (prefix-in easy: net/http-easy)
          html-writing
          web-server/http
@@ -94,7 +95,11 @@
      ,@(map (λ (url)
               `(link (@ (rel "stylesheet") (type "text/css") (href ,url))))
             (required-styles (format "https://~a.fandom.com" wikiname)))
-     (link (@ (rel "stylesheet") (type "text/css") (href "/static/main.css"))))
+     (link (@ (rel "stylesheet") (type "text/css") (href "/static/main.css")))
+     (script "const BWData = "
+             ,(jsexpr->string (hasheq 'wikiname wikiname
+                                      'strict_proxy (config-true? 'strict_proxy))))
+     (script (@ (type "module") (src "/static/search-suggestions.js"))))
     (body (@ (class ,body-class))
           (div (@ (class "main-container"))
                (div (@ (class "fandom-community-header__background tileHorizontally header")))
@@ -103,9 +108,12 @@
                           (div (@ (class "custom-top"))
                                (h1 (@ (class "page-title")) ,title)
                                (nav (@ (class "sitesearch"))
-                                    (form (@ (action ,(format "/~a/search" wikiname)))
-                                          (label "Search "
-                                                 (input (@ (type "text") (name "q")))))))
+                                    (form (@ (action ,(format "/~a/search" wikiname))
+                                             (class "bw-search-form")
+                                             (id "bw-pr-search"))
+                                          (label (@ (for "bw-search-input")) "Search ")
+                                          (input (@ (type "text") (name "q") (id "bw-search-input") (autocomplete "off")))
+                                          (div (@ (class "bw-ss__container"))))))
                           (div (@ (id "content") #;(class "page-content"))
                                (div (@ (id "mw-content-text"))
                                     ,content))

src/page-static.rkt

@@ -19,6 +19,7 @@
 
 (define hash-ext-mime-type
   (hash #".css" #"text/css"
+        #".js" #"text/javascript"
         #".png" #"image/png"
         #".svg" #"image/svg+xml"
         #".txt" #"text/plain"))

static/main.css

@@ -225,6 +225,66 @@ figcaption, .lightbox-caption, .thumbcaption {
     margin-left: 1.2em;
 }
 
+/* (breezewiki) search suggestions */
+.bw-search-form {
+    display: grid;
+    grid-template-columns: auto 1fr;
+    grid-gap: 0px 5px;
+}
+.bw-ss__container {
+    grid-column: 2;
+    position: relative;
+}
+.bw-ss__list {
+    position: absolute;
+    left: 0;
+    right: 0;
+    list-style-type: none;
+    padding: 0;
+    margin: 0;
+    font-size: 14px;
+    background: white;
+    color: black;
+    border: solid #808080;
+    border-width: 0px 1px 1px;
+    box-shadow: 0px 2px 4px rgba(0, 0, 0, 0.5);
+    z-index: 99;
+
+    display: none;
+}
+.bw-ss__list--focus {
+    display: block;
+}
+.bw-ss__list--loading {
+    background: #c0c0c0;
+}
+.bw-ss__input--accepted {
+    background: #fffbc0;
+}
+.bw-ss__preview {
+    padding: 0px 2px;
+    font-style: italic;
+    color: #555;
+}
+.bw-ss__item {
+    display: grid; /* make buttons take the full size */
+}
+.bw-ss__item:hover {
+    background-color: #ddd;
+}
+.bw-ss__button {
+    appearance: none;
+    -moz-appearance: none;
+    border: none;
+    margin: 0;
+    line-height: inherit;
+    background: none;
+    font: inherit;
+    cursor: pointer;
+    padding: 0px 2px;
+    text-align: left;
+}
+
 /* media queries */
 
 /* for reference, cell phone screens are generally 400 px wide, definitely less than 500 px */

static/search-suggestions.js

@@ -0,0 +1,93 @@
+import {h, htm, render, useState, useEffect, createContext, useContext} from "./preact.js"
+const html = htm.bind(h)
+const classNames = classArr => classArr.filter(el => el).join(" ")
+
+const form = document.getElementById("bw-pr-search")
+
+const AcceptSuggestion = createContext(null)
+const hitsPromise = new Map()
+const hitsDone = new Set()
+
+function Suggestion(props) {
+	const acceptSuggestion = useContext(AcceptSuggestion)
+	return html`<li class="bw-ss__item"><button type="button" class="bw-ss__button" onClick=${() => acceptSuggestion(props)}>${props.title}</button></li>`
+}
+
+function fetchSuggestions(query, setSuggestions) {
+	if (query === "") query = "\0"
+	if (hitsPromise.has(query)) return hitsPromise.get(query)
+	const url = new URL(`https://${BWData.wikiname}.fandom.com/api.php`)
+	url.searchParams.set("action", "opensearch")
+	url.searchParams.set("format", "json")
+	url.searchParams.set("namespace", "0") // wiki namespace, 0 is default
+	url.searchParams.set("origin", "*") // mediawiki api cors
+	url.searchParams.set("search", query)
+	const sendUrl = BWData.strict_proxy
+			? "/proxy?" + new URLSearchParams({dest: url})
+			: url
+	const promise = fetch(sendUrl).then(res => res.json()).then(root => {
+		hitsDone.add(query)
+		return Array(root[1].length).fill().map((_, i) => ({
+			title: root[1][i],
+			url: root[3][i]
+		}))
+	})
+	hitsPromise.set(query, promise)
+	return promise
+}
+
+function SuggestionList(props) {
+	return html`
+<div class="bw-ss__container">
+	<ul class=${classNames(["bw-ss__list", props.focus && "bw-ss__list--focus", `bw-ss__list--${props.st}`])}>
+		${props.hits.map(hit => html`<${Suggestion} ...${hit} />`)}
+	</ul>
+</div>`
+}
+
+function ControlledInput() {
+	const [query, setQuery] = useState("")
+	const [focus, setFocus] = useState(false)
+	const [st, setSt] = useState("ready")
+	const [suggestions, setSuggestions] = useState([])
+
+	useEffect(() => {
+		if (st === "accepted") return
+		setSt("loading")
+		fetchSuggestions(query).then(s => {
+			setSuggestions(s)
+			if (hitsDone.size === hitsPromise.size) {
+				setSt("ready")
+			}
+		})
+	}, [query])
+
+	function acceptSuggestion(suggestion) {
+		setQuery(suggestion.title)
+		setSt("accepted")
+		const dest = new URL(suggestion.url).pathname.match("/wiki/.*")
+		location = `/${BWData.wikiname}${dest}`
+	}
+
+	useEffect(() => {
+		function listener(event) {
+			if (event.type === "focusin") setFocus(true)
+			else setFocus(false)
+		}
+		form.addEventListener("focusin", listener)
+		form.addEventListener("focusout", listener)
+		return () => {
+			form.removeEventListener("focusin", listener)
+			form.removeEventListener("focusout", listener)
+		}
+	})
+
+	return html`
+<${AcceptSuggestion.Provider} value=${acceptSuggestion}>
+	<label for="bw-search-input">Search </label>
+	<input type="text" name="q" id="bw-search-input" autocomplete="off" onInput=${e => setQuery(e.target.value)} value=${query} class=${classNames(["bw-ss__input", `bw-ss__input--${st}`])} />
+	<${SuggestionList} hits=${suggestions} focus=${focus} st=${st}/>
+</${AcceptSuggestion.Provider}`
+}
+
+render(html`<${ControlledInput} />`, form)