From 262a1a044f706d8937ba430911359d7c306329e4 Mon Sep 17 00:00:00 2001
From: Raymond Hill <rhill@raymondhill.net>
Date: Wed, 2 Dec 2020 09:09:28 -0500
Subject: [PATCH] Improve auto-complete of hostname values in "My filters"

Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1134

Related commit:
- https://github.com/gorhill/uBlock/commit/daf464b3c30e9c0c5f5991ba1bde8f9dca1d7078
---
 src/js/1p-filters.js                      | 45 +++++++++++++++++------
 src/js/codemirror/ubo-static-filtering.js | 45 ++++++++++++++---------
 src/js/messaging.js                       | 18 +++++----
 3 files changed, 72 insertions(+), 36 deletions(-)

diff --git a/src/js/1p-filters.js b/src/js/1p-filters.js
index 7d70b85ad..647d48cdf 100644
--- a/src/js/1p-filters.js
+++ b/src/js/1p-filters.js
@@ -49,22 +49,43 @@ const cmEditor = new CodeMirror(document.getElementById('userFilters'), {
 
 uBlockDashboard.patchCodeMirrorEditor(cmEditor);
 
-vAPI.messaging.send('dashboard', {
-    what: 'getAutoCompleteDetails'
-}).then(response => {
-    if ( response instanceof Object === false ) { return; }
-    const mode = cmEditor.getMode();
-    // TODO: listen to changes in currently opened set of tabs?
-    if ( mode.setHints instanceof Function ) {
-        mode.setHints(response);
-    }
-    mode.parser.expertMode = response.expertMode !== false;
-});
-
 let cachedUserFilters = '';
 
 /******************************************************************************/
 
+// Add auto-complete ability to the editor.
+
+{
+    let hintUpdateToken = 0;
+
+    const responseHandler = function(response) {
+        if ( response instanceof Object === false ) { return; }
+        if ( response.hintUpdateToken !== undefined ) {
+            const firstVisit = hintUpdateToken === 0;
+            const mode = cmEditor.getMode();
+            if ( mode.setHints instanceof Function ) {
+                mode.setHints(response, firstVisit);
+            }
+            if ( firstVisit ) {
+                mode.parser.expertMode = response.expertMode !== false;
+            }
+            hintUpdateToken = response.hintUpdateToken;
+        }
+        vAPI.setTimeout(getHints, 2503);
+    };
+
+    const getHints = function() {
+        vAPI.messaging.send('dashboard', {
+            what: 'getAutoCompleteDetails',
+            hintUpdateToken
+        }).then(responseHandler);
+    };
+
+    getHints();
+}
+
+/******************************************************************************/
+
 const getEditorText = function() {
     const text = cmEditor.getValue().replace(/\s+$/, '');
     return text === '' ? text : text + '\n';
diff --git a/src/js/codemirror/ubo-static-filtering.js b/src/js/codemirror/ubo-static-filtering.js
index cc55c7548..78a8710c5 100644
--- a/src/js/codemirror/ubo-static-filtering.js
+++ b/src/js/codemirror/ubo-static-filtering.js
@@ -361,26 +361,37 @@ CodeMirror.defineMode('ubo-static-filtering', function() {
             style = style.trim();
             return style !== '' ? style : null;
         },
-        setHints: function(details) {
-            for ( const [ name, desc ] of details.redirectResources ) {
-                const displayText = desc.aliasOf !== ''
-                    ? `${name} (${desc.aliasOf})`
-                    : '';
-                if ( desc.canRedirect ) {
-                    redirectNames.set(name, displayText);
-                }
-                if ( desc.canInject && name.endsWith('.js') ) {
-                    scriptletNames.set(name.slice(0, -3), displayText);
+        setHints: function(details, firstVisit = false) {
+            if ( Array.isArray(details.redirectResources) ) {
+                for ( const [ name, desc ] of details.redirectResources ) {
+                    const displayText = desc.aliasOf !== ''
+                        ? `${name} (${desc.aliasOf})`
+                        : '';
+                    if ( desc.canRedirect ) {
+                        redirectNames.set(name, displayText);
+                    }
+                    if ( desc.canInject && name.endsWith('.js') ) {
+                        scriptletNames.set(name.slice(0, -3), displayText);
+                    }
                 }
             }
-            details.preparseDirectiveTokens.forEach(([ a, b ]) => {
-                preparseDirectiveTokens.set(a, b);
-            });
-            preparseDirectiveHints.push(...details.preparseDirectiveHints);
-            for ( const hint of details.originHints ) {
-                originHints.push(hint);
+            if ( Array.isArray(details.preparseDirectiveTokens)) {
+                details.preparseDirectiveTokens.forEach(([ a, b ]) => {
+                    preparseDirectiveTokens.set(a, b);
+                });
+            }
+            if ( Array.isArray(details.preparseDirectiveHints)) {
+                preparseDirectiveHints.push(...details.preparseDirectiveHints);
+            }
+            if ( Array.isArray(details.originHints) ) {
+                originHints.length = 0;
+                for ( const hint of details.originHints ) {
+                    originHints.push(hint);
+                }
+            }
+            if ( firstVisit ) {
+                initHints();
             }
-            initHints();
         },
         get parser() {
             return parser;
diff --git a/src/js/messaging.js b/src/js/messaging.js
index 5af3d539f..478f2c215 100644
--- a/src/js/messaging.js
+++ b/src/js/messaging.js
@@ -1201,13 +1201,17 @@ const onMessage = function(request, sender, callback) {
         break;
 
     case 'getAutoCompleteDetails':
-        response = {
-            redirectResources: µb.redirectEngine.getResourceDetails(),
-            preparseDirectiveTokens: µb.preparseDirectives.getTokens(),
-            preparseDirectiveHints: µb.preparseDirectives.getHints(),
-            originHints: getOriginHints(),
-            expertMode: µb.hiddenSettings.filterAuthorMode,
-        };
+        response = {};
+        if ( request.hintUpdateToken === 0 ) {
+            response.redirectResources = µb.redirectEngine.getResourceDetails();
+            response.preparseDirectiveTokens = µb.preparseDirectives.getTokens();
+            response.preparseDirectiveHints = µb.preparseDirectives.getHints();
+            response.expertMode = µb.hiddenSettings.filterAuthorMode;
+        }
+        if ( request.hintUpdateToken !== µb.pageStoresToken ) {
+            response.originHints = getOriginHints();
+            response.hintUpdateToken = µb.pageStoresToken;
+        }
         break;
 
     case 'getRules':