Search query offset value (#1968)

* Add type property to TextSource* classes

* Use type property rather than instanceof

* Expose a sentence offset value

* Use offset added to URL

* Improve fallback sentence for Anki note context

7 files changed, 81 insertions, 23 deletions

diff --git a/ext/js/app/frontend.js b/ext/js/app/frontend.js
index ef53cecb..0d358639 100644
--- a/ext/js/app/frontend.js
+++ b/ext/js/app/frontend.js
@@ -18,7 +18,6 @@
 /* global
  * DocumentUtil
  * TextScanner
- * TextSourceElement
  * TextSourceRange
  */
 
@@ -536,7 +535,7 @@ class Frontend {
                 }
             }
         };
-        if (textSource instanceof TextSourceElement && textSource.fullContent !== query) {
+        if (textSource.type === 'element' && textSource.fullContent !== query) {
             details.params.full = textSource.fullContent;
             details.params['full-visible'] = 'true';
         }
diff --git a/ext/js/display/display-anki.js b/ext/js/display/display-anki.js
index d17a2f0f..216e3108 100644
--- a/ext/js/display/display-anki.js
+++ b/ext/js/display/display-anki.js
@@ -216,8 +216,8 @@ class DisplayAnki {
         if (typeof url !== 'string') {
             url = window.location.href;
         }
-        const {query, fullQuery} = this._display;
-        sentence = this._getValidSentenceData(sentence, query);
+        const {query, fullQuery, queryOffset} = this._display;
+        sentence = this._getValidSentenceData(sentence, fullQuery, queryOffset);
         return {
             url,
             sentence,
@@ -565,11 +565,11 @@ class DisplayAnki {
         return isTerms ? ['term-kanji', 'term-kana'] : ['kanji'];
     }
 
-    _getValidSentenceData(sentence, fallback) {
+    _getValidSentenceData(sentence, fallback, fallbackOffset) {
         let {text, offset} = (isObject(sentence) ? sentence : {});
         if (typeof text !== 'string') {
             text = fallback;
-            offset = 0;
+            offset = fallbackOffset;
         } else {
             if (typeof offset !== 'number') { offset = 0; }
         }
diff --git a/ext/js/display/display.js b/ext/js/display/display.js
index 0509e22a..0e82af54 100644
--- a/ext/js/display/display.js
+++ b/ext/js/display/display.js
@@ -73,6 +73,7 @@ class Display extends EventDispatcher {
         this._titleMaxLength = 1000;
         this._query = '';
         this._fullQuery = '';
+        this._queryOffset = 0;
         this._documentUtil = new DocumentUtil();
         this._progressIndicator = document.querySelector('#progress-indicator');
         this._progressIndicatorTimer = null;
@@ -208,6 +209,10 @@ class Display extends EventDispatcher {
         return this._fullQuery;
     }
 
+    get queryOffset() {
+        return this._queryOffset;
+    }
+
     get frameVisible() {
         return this._frameVisible;
     }
@@ -432,7 +437,7 @@ class Display extends EventDispatcher {
         const details = {
             focus: false,
             historyMode: 'clear',
-            params: this._createSearchParams(type, query, false),
+            params: this._createSearchParams(type, query, false, this._queryOffset),
             state,
             content: {
                 dictionaryEntries: null,
@@ -598,9 +603,14 @@ class Display extends EventDispatcher {
                         const isTerms = (type === 'terms');
                         let queryFull = urlSearchParams.get('full');
                         queryFull = (queryFull !== null ? queryFull : query);
+                        let queryOffset = urlSearchParams.get('offset');
+                        if (queryOffset !== null) {
+                            queryOffset = Number.parseInt(queryOffset, 10);
+                            if (!Number.isFinite(queryOffset)) { queryOffset = null; }
+                        }
                         const wildcardsEnabled = (urlSearchParams.get('wildcards') !== 'off');
                         const lookup = (urlSearchParams.get('lookup') !== 'false');
-                        await this._setContentTermsOrKanji(token, isTerms, query, queryFull, lookup, wildcardsEnabled, eventArgs);
+                        await this._setContentTermsOrKanji(token, isTerms, query, queryFull, queryOffset, lookup, wildcardsEnabled, eventArgs);
                     }
                     break;
                 case 'unloaded':
@@ -633,7 +643,7 @@ class Display extends EventDispatcher {
         }
     }
 
-    _onQueryParserSearch({type, dictionaryEntries, sentence, inputInfo: {eventType}, textSource, optionsContext}) {
+    _onQueryParserSearch({type, dictionaryEntries, sentence, inputInfo: {eventType}, textSource, optionsContext, sentenceOffset}) {
         const query = textSource.text();
         const historyState = this._history.state;
         const historyMode = (
@@ -644,7 +654,7 @@ class Display extends EventDispatcher {
         const details = {
             focus: false,
             historyMode,
-            params: this._createSearchParams(type, query, false),
+            params: this._createSearchParams(type, query, false, sentenceOffset),
             state: {
                 sentence,
                 optionsContext,
@@ -724,7 +734,7 @@ class Display extends EventDispatcher {
             const details = {
                 focus: false,
                 historyMode: 'new',
-                params: this._createSearchParams('kanji', query, false),
+                params: this._createSearchParams('kanji', query, false, null),
                 state: {
                     focusEntry: 0,
                     optionsContext,
@@ -887,7 +897,7 @@ class Display extends EventDispatcher {
         }
     }
 
-    async _setContentTermsOrKanji(token, isTerms, query, queryFull, lookup, wildcardsEnabled, eventArgs) {
+    async _setContentTermsOrKanji(token, isTerms, query, queryFull, queryOffset, lookup, wildcardsEnabled, eventArgs) {
         let {state, content} = this._history;
         let changeHistory = false;
         if (!isObject(content)) {
@@ -912,7 +922,11 @@ class Display extends EventDispatcher {
             changeHistory = true;
         }
 
-        this._setFullQuery(queryFull);
+        if (queryOffset !== null) {
+            queryOffset = Math.max(0, Math.min(queryFull.length - query.length, queryOffset));
+        }
+
+        this._setFullQuery(queryFull, queryOffset);
         this._setTitleText(query);
 
         let {dictionaryEntries} = content;
@@ -1015,13 +1029,13 @@ class Display extends EventDispatcher {
         this._updateNavigation(false, false);
         this._setNoContentVisible(false);
         this._setTitleText('');
-        this._setFullQuery('');
+        this._setFullQuery('', 0);
     }
 
     _clearContent() {
         this._container.textContent = '';
         this._setTitleText('');
-        this._setFullQuery('');
+        this._setFullQuery('', 0);
     }
 
     _setNoContentVisible(visible) {
@@ -1032,8 +1046,9 @@ class Display extends EventDispatcher {
         }
     }
 
-    _setFullQuery(text) {
+    _setFullQuery(text, offset) {
         this._fullQuery = text;
+        this._queryOffset = offset;
         this._updateQueryParser();
     }
 
@@ -1200,12 +1215,17 @@ class Display extends EventDispatcher {
         }
     }
 
-    _createSearchParams(type, query, wildcards) {
+    _createSearchParams(type, query, wildcards, sentenceOffset) {
         const params = {};
-        if (query.length < this._fullQuery.length) {
-            params.full = this._fullQuery;
+        const fullQuery = this._fullQuery;
+        const includeFull = (query.length < fullQuery.length);
+        if (includeFull) {
+            params.full = fullQuery;
         }
         params.query = query;
+        if (includeFull && sentenceOffset !== null) {
+            params.offset = `${sentenceOffset}`;
+        }
         if (typeof type === 'string') {
             params.type = type;
         }
diff --git a/ext/js/display/query-parser.js b/ext/js/display/query-parser.js
index cbcf7cff..e2578fcf 100644
--- a/ext/js/display/query-parser.js
+++ b/ext/js/display/query-parser.js
@@ -117,6 +117,8 @@ class QueryParser extends EventDispatcher {
         }
         if (e.type === null) { return; }
 
+        e.sentenceOffset = this._getSentenceOffset(e.textSource);
+
         this.trigger('searched', e);
     }
 
@@ -208,29 +210,33 @@ class QueryParser extends EventDispatcher {
     }
 
     _createParseResult(data) {
+        let offset = 0;
         const fragment = document.createDocumentFragment();
         for (const term of data) {
             const termNode = document.createElement('span');
             termNode.className = 'query-parser-term';
+            termNode.dataset.offset = `${offset}`;
             for (const {text, reading} of term) {
                 if (reading.length === 0) {
                     termNode.appendChild(document.createTextNode(text));
                 } else {
                     const reading2 = this._convertReading(text, reading);
-                    termNode.appendChild(this._createSegment(text, reading2));
+                    termNode.appendChild(this._createSegment(text, reading2, offset));
                 }
+                offset += text.length;
             }
             fragment.appendChild(termNode);
         }
         return fragment;
     }
 
-    _createSegment(text, reading) {
+    _createSegment(text, reading, offset) {
         const segmentNode = document.createElement('ruby');
         segmentNode.className = 'query-parser-segment';
 
         const textNode = document.createElement('span');
         textNode.className = 'query-parser-segment-text';
+        textNode.dataset.offset = `${offset}`;
 
         const readingNode = document.createElement('rt');
         readingNode.className = 'query-parser-segment-reading';
@@ -265,4 +271,30 @@ class QueryParser extends EventDispatcher {
                 return reading;
         }
     }
+
+    _getSentenceOffset(textSource) {
+        if (textSource.type === 'range') {
+            const {range} = textSource;
+            const node = this._getParentElement(range.startContainer);
+            if (node !== null) {
+                const {offset} = node.dataset;
+                if (typeof offset === 'string') {
+                    const value = Number.parseInt(offset, 10);
+                    if (Number.isFinite(value)) {
+                        return Math.max(0, value) + range.startOffset;
+                    }
+                }
+            }
+        }
+        return null;
+    }
+
+    _getParentElement(node) {
+        const {ELEMENT_NODE} = Node;
+        while (true) {
+            node = node.parentNode;
+            if (node === null) { return null; }
+            if (node.nodeType === ELEMENT_NODE) { return node; }
+        }
+    }
 }
diff --git a/ext/js/dom/text-source-element.js b/ext/js/dom/text-source-element.js
index 499ee45d..11bf7eb0 100644
--- a/ext/js/dom/text-source-element.js
+++ b/ext/js/dom/text-source-element.js
@@ -24,6 +24,10 @@ class TextSourceElement {
         this._content = this._fullContent.substring(this._startOffset, this._endOffset);
     }
 
+    get type() {
+        return 'element';
+    }
+
     get element() {
         return this._element;
     }
diff --git a/ext/js/dom/text-source-range.js b/ext/js/dom/text-source-range.js
index 377016da..591429da 100644
--- a/ext/js/dom/text-source-range.js
+++ b/ext/js/dom/text-source-range.js
@@ -29,6 +29,10 @@ class TextSourceRange {
         this._imposterSourceElement = imposterSourceElement;
     }
 
+    get type() {
+        return 'range';
+    }
+
     get range() {
         return this._range;
     }
diff --git a/ext/js/language/text-scanner.js b/ext/js/language/text-scanner.js
index c7cedd7e..5d37c84b 100644
--- a/ext/js/language/text-scanner.js
+++ b/ext/js/language/text-scanner.js
@@ -17,7 +17,6 @@
 
 /* global
  * DocumentUtil
- * TextSourceElement
  */
 
 class TextScanner extends EventDispatcher {
@@ -345,7 +344,7 @@ class TextScanner extends EventDispatcher {
             if (result !== null) {
                 ({dictionaryEntries, sentence, type} = result);
                 valid = true;
-            } else if (textSource instanceof TextSourceElement && await this._hasJapanese(textSource.fullContent)) {
+            } else if (textSource !== null && textSource.type === 'element' && await this._hasJapanese(textSource.fullContent)) {
                 dictionaryEntries = [];
                 sentence = {sentence: '', offset: 0};
                 type = 'terms';