1 files changed, 239 insertions, 0 deletions
diff --git a/src/static/js/client/wiki-search.js b/src/static/js/client/wiki-search.js
new file mode 100644
index 00000000..2446c172
--- /dev/null
+++ b/src/static/js/client/wiki-search.js
@@ -0,0 +1,239 @@
+/* eslint-env browser */
+
+import {promiseWithResolvers} from '../../shared-util/sugar.js';
+
+import {dispatchInternalEvent} from '../client-util.js';
+
+export const info = {
+  id: 'wikiSearchInfo',
+
+  state: {
+    worker: null,
+
+    workerReadyPromise: null,
+    workerReadyPromiseResolvers: null,
+
+    workerActionCounter: 0,
+    workerActionPromiseResolverMap: new Map(),
+
+    downloads: Object.create(null),
+  },
+
+  event: {
+    whenWorkerAlive: [],
+    whenWorkerReady: [],
+    whenWorkerFailsToInitialize: [],
+    whenWorkerHasRuntimeError: [],
+
+    whenDownloadBegins: [],
+    whenDownloadsBegin: [],
+    whenDownloadProgresses: [],
+    whenDownloadEnds: [],
+  },
+};
+
+export async function initializeSearchWorker() {
+  const {state} = info;
+
+  if (state.worker) {
+    return await state.workerReadyPromise;
+  }
+
+  state.worker =
+    new Worker(
+      import.meta.resolve('../search-worker.js'),
+      {type: 'module'});
+
+  state.worker.onmessage = handleSearchWorkerMessage;
+
+  const {promise, resolve, reject} = promiseWithResolvers();
+
+  state.workerReadyPromiseResolvers = {resolve, reject};
+
+  return await (state.workerReadyPromise = promise);
+}
+
+function handleSearchWorkerMessage(message) {
+  switch (message.data.kind) {
+    case 'status':
+      handleSearchWorkerStatusMessage(message);
+      break;
+
+    case 'result':
+      handleSearchWorkerResultMessage(message);
+      break;
+
+    case 'download-begun':
+      handleSearchWorkerDownloadBegunMessage(message);
+      break;
+
+    case 'download-progress':
+      handleSearchWorkerDownloadProgressMessage(message);
+      break;
+
+    case 'download-complete':
+      handleSearchWorkerDownloadCompleteMessage(message);
+      break;
+
+    default:
+      console.warn(`Unknown message kind "${message.data.kind}" <- from search worker`);
+      break;
+  }
+}
+
+function handleSearchWorkerStatusMessage(message) {
+  const {state, event} = info;
+
+  switch (message.data.status) {
+    case 'alive':
+      console.debug(`Search worker is alive, but not yet ready.`);
+      dispatchInternalEvent(event, 'whenWorkerAlive');
+      break;
+
+    case 'ready':
+      console.debug(`Search worker has loaded corpuses and is ready.`);
+      state.workerReadyPromiseResolvers.resolve(state.worker);
+      dispatchInternalEvent(event, 'whenWorkerReady');
+      break;
+
+    case 'setup-error':
+      console.debug(`Search worker failed to initialize.`);
+      state.workerReadyPromiseResolvers.reject(new Error('Received "setup-error" status from worker'));
+      dispatchInternalEvent(event, 'whenWorkerFailsToInitialize');
+      break;
+
+    case 'runtime-error':
+      console.debug(`Search worker had an uncaught runtime error.`);
+      dispatchInternalEvent(event, 'whenWorkerHasRuntimeError');
+      break;
+
+    default:
+      console.warn(`Unknown status "${message.data.status}" <- from search worker`);
+      break;
+  }
+}
+
+function handleSearchWorkerResultMessage(message) {
+  const {state} = info;
+  const {id} = message.data;
+
+  if (!id) {
+    console.warn(`Result without id <- from search worker:`, message.data);
+    return;
+  }
+
+  if (!state.workerActionPromiseResolverMap.has(id)) {
+    console.warn(`Runaway result id <- from search worker:`, message.data);
+    return;
+  }
+
+  const {resolve, reject} =
+    state.workerActionPromiseResolverMap.get(id);
+
+  switch (message.data.status) {
+    case 'resolve':
+      resolve(message.data.value);
+      break;
+
+    case 'reject':
+      reject(message.data.value);
+      break;
+
+    default:
+      console.warn(`Unknown result status "${message.data.status}" <- from search worker`);
+      return;
+  }
+
+  state.workerActionPromiseResolverMap.delete(id);
+}
+
+function handleSearchWorkerDownloadBegunMessage(message) {
+  const {event} = info;
+  const {context: contextKey, keys} = message.data;
+
+  const context = getSearchWorkerDownloadContext(contextKey, true);
+
+  for (const key of keys) {
+    context[key] = 0.00;
+
+    dispatchInternalEvent(event, 'whenDownloadBegins', {
+      context: contextKey,
+      key,
+    });
+  }
+
+  dispatchInternalEvent(event, 'whenDownloadsBegin', {
+    context: contextKey,
+    keys,
+  });
+}
+
+function handleSearchWorkerDownloadProgressMessage(message) {
+  const {event} = info;
+  const {context: contextKey, key, progress} = message.data;
+
+  const context = getSearchWorkerDownloadContext(contextKey);
+
+  context[key] = progress;
+
+  dispatchInternalEvent(event, 'whenDownloadProgresses', {
+    context: contextKey,
+    key,
+    progress,
+  });
+}
+
+function handleSearchWorkerDownloadCompleteMessage(message) {
+  const {event} = info;
+  const {context: contextKey, key} = message.data;
+
+  const context = getSearchWorkerDownloadContext(contextKey);
+
+  context[key] = 1.00;
+
+  dispatchInternalEvent(event, 'whenDownloadEnds', {
+    context: contextKey,
+    key,
+  });
+}
+
+export function getSearchWorkerDownloadContext(context, initialize = false) {
+  const {state} = info;
+
+  if (context in state.downloads) {
+    return state.downloads[context];
+  }
+
+  if (!initialize) {
+    return null;
+  }
+
+  return state.downloads[context] = Object.create(null);
+}
+
+export async function postSearchWorkerAction(action, options) {
+  const {state} = info;
+
+  const worker = await initializeSearchWorker();
+  const id = ++state.workerActionCounter;
+
+  const {promise, resolve, reject} = promiseWithResolvers();
+
+  state.workerActionPromiseResolverMap.set(id, {resolve, reject});
+
+  worker.postMessage({
+    kind: 'action',
+    action: action,
+    id,
+    options,
+  });
+
+  return await promise;
+}
+
+export async function searchAll(query, options = {}) {
+  return await postSearchWorkerAction('search', {
+    query,
+    options,
+  });
+}