js/index.js

@@ -0,0 +1,108 @@
+const storageType = 'localStorage'
+
+let data = {}
+
+const statusEl = document.getElementById('status')
+const formEl = document.getElementById('search')
+
+const errors = {
+  missingQuery: new TypeError('Query is missing.'),
+  noFoundInstances: new Error('No instances were found.'),
+}
+
+function buildSearchURL (opts = {}) {
+  if (typeof opts.query !== 'string') throw errors.missingQuery
+  if (!('instances' in data)) throw errors.noFoundInstances
+  if (data.instances.length === 0) throw errors.noFoundInstances
+
+  // Random instance
+  const n = Math.floor(Math.random() * data.instances.length)
+  const instanceURL = data.instances[n]
+
+  // Build URL
+  const params = new URLSearchParams({
+    q: opts.query
+  })
+  if (opts.category && opts.category !== 'all') {
+    params.append(`category_${opts.category}`, '')
+  }
+  const url = `${instanceURL}?${params.toString()}`
+  return url
+}
+
+// Register event listeners
+formEl.addEventListener('submit', (event) => {
+  event.preventDefault()
+  location.assign(buildSearchURL({
+    query: formEl.query.value,
+    category: formEl.category.value
+  }))
+})
+
+function locallyGetInstances () {
+  if (!(storageType in window)) return []
+  const item = window[storageType].getItem('instances')
+  try {
+    return JSON.parse(item)
+  } catch (_err) {
+    return []
+  }
+}
+
+function locallySetInstances () {
+  if (!(storageType in window)) return
+  if (!('instances' in data)) return
+  if (data.instances.length === 0) return
+  window[storageType].setItem(
+    'instances',
+    JSON.stringify(data.instances)
+  )
+}
+
+async function remotelyGetInstances () {
+  const instances = await fetch('https://searx.space/data/instances.json')
+    .then((req) => req.json())
+    .then((json) => Object.entries(json.instances))
+    .then((entries) => entries.filter(([_url, details]) => {
+      if (details.network_type !== 'normal') return
+      if (details.uptime == null) return
+      if (details.uptime.uptimeDay !== 100) return
+      return true
+    }))
+    .then((entries) => entries.map(([url]) => url))
+    .catch((err) => {
+      console.error(err)
+      return []
+    })
+  window[storageType].setItem('timestamp', Date.now().toString())
+  return instances
+}
+
+// Get local instances
+data.instances = locallyGetInstances()
+
+// Fetch remote instances if necessary
+const timestamp = +window[storageType].getItem('timestamp')
+if (Date.now() > timestamp + 3_600_000 /* 1 hour */) {
+  const remoteInstances = await remotelyGetInstances()
+  if (remoteInstances.length > 0) {
+    data.instances = remoteInstances
+    locallySetInstances()
+  }
+}
+
+// Auto-redirect in presence of search parameters
+if (location.search.length > 0) {
+  const searchParams = new URLSearchParams(location.search.slice(1))
+  if (searchParams.has('q')) {
+    location.assign(buildSearchURL({
+      query: searchParams.get('q'),
+      category: searchParams.get('in') ?? 'all'
+    }))
+  }
+}
+
+statusEl.textContent = `${data.instances.length} instances`
+if (data.instances.length === 0) {
+  statusEl.classList.add('error')
+}