Refactor anki field templates (#1323)

* Update glossary and glossary-single

* Define patch

* Create TemplatePatcher

* Add test

7 files changed, 238 insertions, 55 deletions

diff --git a/ext/bg/background.html b/ext/bg/background.html
index e139514d..29cae072 100644
--- a/ext/bg/background.html
+++ b/ext/bg/background.html
@@ -40,6 +40,7 @@
         <script src="/bg/js/profile-conditions.js"></script>
         <script src="/bg/js/request-builder.js"></script>
         <script src="/bg/js/native-simple-dom-parser.js"></script>
+        <script src="/bg/js/template-patcher.js"></script>
         <script src="/bg/js/text-source-map.js"></script>
         <script src="/bg/js/translator.js"></script>
 
diff --git a/ext/bg/data/anki-field-templates-upgrade-v8.handlebars b/ext/bg/data/anki-field-templates-upgrade-v8.handlebars
index a5056364..32c61343 100644
--- a/ext/bg/data/anki-field-templates-upgrade-v8.handlebars
+++ b/ext/bg/data/anki-field-templates-upgrade-v8.handlebars
@@ -12,3 +12,108 @@
         {{~/if~}}
     {{~/scope~}}
 {{/inline}}
+
+{{<<<<<<<}}
+{{#*inline "glossary-single"}}
+    {{~#unless brief~}}
+        {{~#scope~}}
+            {{~#set "any" false}}{{/set~}}
+            {{~#if definitionTags~}}{{#each definitionTags~}}
+                {{~#if (op "||" (op "!" ../data.compactTags) (op "!" redundant))~}}
+                    {{~#if (get "any")}}, {{else}}<i>({{/if~}}
+                    {{name}}
+                    {{~#set "any" true}}{{/set~}}
+                {{~/if~}}
+            {{~/each~}}
+            {{~#if (get "any")}})</i> {{/if~}}
+            {{~/if~}}
+        {{~/scope~}}
+        {{~#if only~}}({{#each only}}{{{.}}}{{#unless @last}}, {{/unless}}{{/each}} only) {{/if~}}
+    {{~/unless~}}
+    {{~#if glossary.[1]~}}
+        {{~#if compactGlossaries~}}
+            {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{#unless @last}} | {{/unless}}{{/each}}
+        {{~else~}}
+            <ul>{{#each glossary}}<li>{{#multiLine}}{{.}}{{/multiLine}}</li>{{/each}}</ul>
+        {{~/if~}}
+    {{~else~}}
+        {{~#multiLine}}{{glossary.[0]}}{{/multiLine~}}
+    {{~/if~}}
+{{/inline}}
+{{=======}}
+{{#*inline "glossary-single"}}
+    {{~#unless brief~}}
+        {{~#scope~}}
+            {{~#set "any" false}}{{/set~}}
+            {{~#each definitionTags~}}
+                {{~#if (op "||" (op "!" @root.compactTags) (op "!" redundant))~}}
+                    {{~#if (get "any")}}, {{else}}<i>({{/if~}}
+                    {{name}}
+                    {{~#set "any" true}}{{/set~}}
+                {{~/if~}}
+            {{~/each~}}
+            {{~#if (get "any")}})</i> {{/if~}}
+        {{~/scope~}}
+        {{~#if only~}}({{#each only}}{{.}}{{#unless @last}}, {{/unless}}{{/each}} only) {{/if~}}
+    {{~/unless~}}
+    {{~#if (op "<=" glossary.length 1)~}}
+        {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{/each}}
+    {{~else if @root.compactGlossaries~}}
+        {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{#unless @last}} | {{/unless}}{{/each}}
+    {{~else~}}
+        <ul>{{#each glossary}}<li>{{#multiLine}}{{.}}{{/multiLine}}</li>{{/each}}</ul>
+    {{~/if~}}
+{{/inline}}
+{{>>>>>>>}}
+
+{{<<<<<<<}}
+{{#*inline "glossary"}}
+    <div style="text-align: left;">
+    {{~#if modeKanji~}}
+        {{~#if definition.glossary.[1]~}}
+            <ol>{{#each definition.glossary}}<li>{{.}}</li>{{/each}}</ol>
+        {{~else~}}
+            {{definition.glossary.[0]}}
+        {{~/if~}}
+    {{~else~}}
+        {{~#if group~}}
+            {{~#if definition.definitions.[1]~}}
+                <ol>{{#each definition.definitions}}<li>{{> glossary-single brief=../brief compactGlossaries=../compactGlossaries data=../.}}</li>{{/each}}</ol>
+            {{~else~}}
+                {{~> glossary-single definition.definitions.[0] brief=brief compactGlossaries=compactGlossaries data=.~}}
+            {{~/if~}}
+        {{~else if merge~}}
+            {{~#if definition.definitions.[1]~}}
+                <ol>{{#each definition.definitions}}<li>{{> glossary-single brief=../brief compactGlossaries=../compactGlossaries data=../.}}</li>{{/each}}</ol>
+            {{~else~}}
+                {{~> glossary-single definition.definitions.[0] brief=brief compactGlossaries=compactGlossaries data=.~}}
+            {{~/if~}}
+        {{~else~}}
+            {{~> glossary-single definition brief=brief compactGlossaries=compactGlossaries data=.~}}
+        {{~/if~}}
+    {{~/if~}}
+    </div>
+{{/inline}}
+{{=======}}
+{{~#*inline "glossary"~}}
+    <div style="text-align: left;">
+    {{~#scope~}}
+        {{~#if (op "===" definition.type "term")~}}
+            {{~> glossary-single definition brief=brief ~}}
+        {{~else if (op "||" (op "===" definition.type "termGrouped") (op "===" definition.type "termMerged"))~}}
+            {{~#if (op ">" definition.definitions.length 1)~}}
+                <ol>{{~#each definition.definitions~}}<li>{{~> glossary-single . brief=../brief ~}}</li>{{~/each~}}</ol>
+            {{~else~}}
+                {{~#each definition.definitions~}}{{~> glossary-single . brief=../brief ~}}{{~/each~}}
+            {{~/if~}}
+        {{~else if (op "===" definition.type "kanji")~}}
+            {{~#if (op ">" definition.glossary.length 1)~}}
+                <ol>{{#each definition.glossary}}<li>{{.}}</li>{{/each}}</ol>
+            {{~else~}}
+                {{~#each definition.glossary~}}{{.}}{{~/each~}}
+            {{~/if~}}
+        {{~/if~}}
+    {{~/scope~}}
+    </div>
+{{~/inline~}}
+{{>>>>>>>}}
diff --git a/ext/bg/data/default-anki-field-templates.handlebars b/ext/bg/data/default-anki-field-templates.handlebars
index a0aff5d2..94553183 100644
--- a/ext/bg/data/default-anki-field-templates.handlebars
+++ b/ext/bg/data/default-anki-field-templates.handlebars
@@ -2,26 +2,23 @@
     {{~#unless brief~}}
         {{~#scope~}}
             {{~#set "any" false}}{{/set~}}
-            {{~#if definitionTags~}}{{#each definitionTags~}}
-                {{~#if (op "||" (op "!" ../data.compactTags) (op "!" redundant))~}}
+            {{~#each definitionTags~}}
+                {{~#if (op "||" (op "!" @root.compactTags) (op "!" redundant))~}}
                     {{~#if (get "any")}}, {{else}}<i>({{/if~}}
                     {{name}}
                     {{~#set "any" true}}{{/set~}}
                 {{~/if~}}
             {{~/each~}}
             {{~#if (get "any")}})</i> {{/if~}}
-            {{~/if~}}
         {{~/scope~}}
-        {{~#if only~}}({{#each only}}{{{.}}}{{#unless @last}}, {{/unless}}{{/each}} only) {{/if~}}
+        {{~#if only~}}({{#each only}}{{.}}{{#unless @last}}, {{/unless}}{{/each}} only) {{/if~}}
     {{~/unless~}}
-    {{~#if glossary.[1]~}}
-        {{~#if compactGlossaries~}}
-            {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{#unless @last}} | {{/unless}}{{/each}}
-        {{~else~}}
-            <ul>{{#each glossary}}<li>{{#multiLine}}{{.}}{{/multiLine}}</li>{{/each}}</ul>
-        {{~/if~}}
+    {{~#if (op "<=" glossary.length 1)~}}
+        {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{/each}}
+    {{~else if @root.compactGlossaries~}}
+        {{#each glossary}}{{#multiLine}}{{.}}{{/multiLine}}{{#unless @last}} | {{/unless}}{{/each}}
     {{~else~}}
-        {{~#multiLine}}{{glossary.[0]}}{{/multiLine~}}
+        <ul>{{#each glossary}}<li>{{#multiLine}}{{.}}{{/multiLine}}</li>{{/each}}</ul>
     {{~/if~}}
 {{/inline}}
 
@@ -92,33 +89,27 @@
     {{~/if~}}
 {{/inline}}
 
-{{#*inline "glossary"}}
+{{~#*inline "glossary"~}}
     <div style="text-align: left;">
-    {{~#if modeKanji~}}
-        {{~#if definition.glossary.[1]~}}
-            <ol>{{#each definition.glossary}}<li>{{.}}</li>{{/each}}</ol>
-        {{~else~}}
-            {{definition.glossary.[0]}}
-        {{~/if~}}
-    {{~else~}}
-        {{~#if group~}}
-            {{~#if definition.definitions.[1]~}}
-                <ol>{{#each definition.definitions}}<li>{{> glossary-single brief=../brief compactGlossaries=../compactGlossaries data=../.}}</li>{{/each}}</ol>
+    {{~#scope~}}
+        {{~#if (op "===" definition.type "term")~}}
+            {{~> glossary-single definition brief=brief ~}}
+        {{~else if (op "||" (op "===" definition.type "termGrouped") (op "===" definition.type "termMerged"))~}}
+            {{~#if (op ">" definition.definitions.length 1)~}}
+                <ol>{{~#each definition.definitions~}}<li>{{~> glossary-single . brief=../brief ~}}</li>{{~/each~}}</ol>
             {{~else~}}
-                {{~> glossary-single definition.definitions.[0] brief=brief compactGlossaries=compactGlossaries data=.~}}
+                {{~#each definition.definitions~}}{{~> glossary-single . brief=../brief ~}}{{~/each~}}
             {{~/if~}}
-        {{~else if merge~}}
-            {{~#if definition.definitions.[1]~}}
-                <ol>{{#each definition.definitions}}<li>{{> glossary-single brief=../brief compactGlossaries=../compactGlossaries data=../.}}</li>{{/each}}</ol>
+        {{~else if (op "===" definition.type "kanji")~}}
+            {{~#if (op ">" definition.glossary.length 1)~}}
+                <ol>{{#each definition.glossary}}<li>{{.}}</li>{{/each}}</ol>
             {{~else~}}
-                {{~> glossary-single definition.definitions.[0] brief=brief compactGlossaries=compactGlossaries data=.~}}
+                {{~#each definition.glossary~}}{{.}}{{~/each~}}
             {{~/if~}}
-        {{~else~}}
-            {{~> glossary-single definition brief=brief compactGlossaries=compactGlossaries data=.~}}
         {{~/if~}}
-    {{~/if~}}
+    {{~/scope~}}
     </div>
-{{/inline}}
+{{~/inline~}}
 
 {{#*inline "glossary-brief"}}
     {{~> glossary brief=true ~}}
diff --git a/ext/bg/js/options.js b/ext/bg/js/options.js
index 02caa5a2..9e0e9cf0 100644
--- a/ext/bg/js/options.js
+++ b/ext/bg/js/options.js
@@ -17,11 +17,13 @@
 
 /* global
  * JsonSchemaValidator
+ * TemplatePatcher
  */
 
 class OptionsUtil {
     constructor() {
         this._schemaValidator = new JsonSchemaValidator();
+        this._templatePatcher = null;
         this._optionsSchema = null;
     }
 
@@ -381,32 +383,22 @@ class OptionsUtil {
 
     // Private
 
-    async _addFieldTemplatesToOptions(options, additionSourceUrl) {
-        let addition = null;
+    async _applyAnkiFieldTemplatesPatch(options, modificationsUrl) {
+        let patch = null;
         for (const {options: profileOptions} of options.profiles) {
             const fieldTemplates = profileOptions.anki.fieldTemplates;
-            if (fieldTemplates !== null) {
-                if (addition === null) {
-                    addition = await this._fetchAsset(additionSourceUrl);
+            if (fieldTemplates === null) { continue; }
+
+            if (patch === null) {
+                const content = await this._fetchAsset(modificationsUrl);
+                if (this._templatePatcher === null) {
+                    this._templatePatcher = new TemplatePatcher();
                 }
-                profileOptions.anki.fieldTemplates = this._addFieldTemplatesBeforeEnd(fieldTemplates, addition);
+                patch = this._templatePatcher.parsePatch(content);
             }
-        }
-    }
 
-    _addFieldTemplatesBeforeEnd(fieldTemplates, addition) {
-        const pattern = /[ \t]*\{\{~?>\s*\(\s*lookup\s*\.\s*"marker"\s*\)\s*~?\}\}/g;
-        const newline = '\n';
-        let replaced = false;
-        fieldTemplates = fieldTemplates.replace(pattern, (g0) => {
-            replaced = true;
-            return `${addition}${newline}${g0}`;
-        });
-        if (!replaced) {
-            fieldTemplates += newline;
-            fieldTemplates += addition;
+            profileOptions.anki.fieldTemplates = this._templatePatcher.applyPatch(fieldTemplates, patch);
         }
-        return fieldTemplates;
     }
 
     async _fetchAsset(url, json=false) {
@@ -495,7 +487,7 @@ class OptionsUtil {
     async _updateVersion3(options) {
         // Version 3 changes:
         //  Pitch accent Anki field templates added.
-        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v2.handlebars');
+        await this._applyAnkiFieldTemplatesPatch(options, '/bg/data/anki-field-templates-upgrade-v2.handlebars');
         return options;
     }
 
@@ -580,7 +572,7 @@ class OptionsUtil {
             });
             profileOptions.scanning.inputs = scanningInputs;
         }
-        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v4.handlebars');
+        await this._applyAnkiFieldTemplatesPatch(options, '/bg/data/anki-field-templates-upgrade-v4.handlebars');
         return options;
     }
 
@@ -600,7 +592,7 @@ class OptionsUtil {
         //  Added global option useSettingsV2.
         //  Added anki.checkForDuplicates.
         //  Added general.glossaryLayoutMode; removed general.compactGlossaries.
-        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v6.handlebars');
+        await this._applyAnkiFieldTemplatesPatch(options, '/bg/data/anki-field-templates-upgrade-v6.handlebars');
         options.global.showPopupPreview = false;
         options.global.useSettingsV2 = false;
         for (const profile of options.profiles) {
@@ -673,7 +665,7 @@ class OptionsUtil {
         //  Moved general.enableClipboardMonitor => clipboard.enableSearchPageMonitor. Forced value to false due to a bug which caused its value to not be read.
         //  Moved general.maximumClipboardSearchLength => clipboard.maximumSearchLength.
         //  Added clipboard.autoSearchContent.
-        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v8.handlebars');
+        await this._applyAnkiFieldTemplatesPatch(options, '/bg/data/anki-field-templates-upgrade-v8.handlebars');
         options.global.useSettingsV2 = true;
         for (const profile of options.profiles) {
             profile.options.translation.textReplacements = {
diff --git a/ext/bg/js/template-patcher.js b/ext/bg/js/template-patcher.js
new file mode 100644
index 00000000..57178957
--- /dev/null
+++ b/ext/bg/js/template-patcher.js
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2021  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+class TemplatePatcher {
+    constructor() {
+        this._diffPattern1 = /\n?\{\{<<<<<<<\}\}\n/g;
+        this._diffPattern2 = /\n\{\{=======\}\}\n/g;
+        this._diffPattern3 = /\n\{\{>>>>>>>\}\}\n*/g;
+        this._lookupMarkerPattern = /[ \t]*\{\{~?>\s*\(\s*lookup\s*\.\s*"marker"\s*\)\s*~?\}\}/g;
+    }
+
+    parsePatch(content) {
+        const diffPattern1 = this._diffPattern1;
+        const diffPattern2 = this._diffPattern2;
+        const diffPattern3 = this._diffPattern3;
+        const modifications = [];
+        let index = 0;
+
+        while (true) {
+            // Find modification boundaries
+            diffPattern1.lastIndex = index;
+            const m1 = diffPattern1.exec(content);
+            if (m1 === null) { break; }
+
+            diffPattern2.lastIndex = m1.index + m1[0].length;
+            const m2 = diffPattern2.exec(content);
+            if (m2 === null) { break; }
+
+            diffPattern3.lastIndex = m2.index + m2[0].length;
+            const m3 = diffPattern3.exec(content);
+            if (m3 === null) { break; }
+
+            // Construct
+            const current = content.substring(m1.index + m1[0].length, m2.index);
+            const replacement = content.substring(m2.index + m2[0].length, m3.index);
+
+            if (current.length > 0) {
+                modifications.push({current, replacement});
+            }
+
+            // Update
+            content = content.substring(0, m1.index) + content.substring(m3.index + m3[0].length);
+            index = m1.index;
+        }
+
+        return {addition: content, modifications};
+    }
+
+    applyPatch(template, patch) {
+        for (const {current, replacement} of patch.modifications) {
+            let fromIndex = 0;
+            while (true) {
+                const index = template.indexOf(current, fromIndex);
+                if (index < 0) { break; }
+                template = template.substring(0, index) + replacement + template.substring(index + current.length);
+                fromIndex = index + replacement.length;
+            }
+        }
+        template = this._addFieldTemplatesBeforeEnd(template, patch.addition);
+        return template;
+    }
+
+    // Private
+
+    _addFieldTemplatesBeforeEnd(template, addition) {
+        const newline = '\n';
+        let replaced = false;
+        template = template.replace(this._lookupMarkerPattern, (g0) => {
+            replaced = true;
+            return `${addition}${newline}${g0}`;
+        });
+        if (!replaced) {
+            template += newline;
+            template += addition;
+        }
+        return template;
+    }
+}
diff --git a/ext/bg/settings.html b/ext/bg/settings.html
index e09a180e..2ccb7a1e 100644
--- a/ext/bg/settings.html
+++ b/ext/bg/settings.html
@@ -1305,6 +1305,7 @@
         <script src="/bg/js/dictionary-importer.js"></script>
         <script src="/bg/js/json-schema.js"></script>
         <script src="/bg/js/media-utility.js"></script>
+        <script src="/bg/js/template-patcher.js"></script>
         <script src="/bg/js/template-renderer-proxy.js"></script>
 
         <script src="/bg/js/settings/keyboard-mouse-input-field.js"></script>
diff --git a/ext/bg/settings2.html b/ext/bg/settings2.html
index 63498020..d557d366 100644
--- a/ext/bg/settings2.html
+++ b/ext/bg/settings2.html
@@ -3208,6 +3208,7 @@
 <script src="/bg/js/dictionary-importer.js"></script>
 <script src="/bg/js/json-schema.js"></script>
 <script src="/bg/js/media-utility.js"></script>
+<script src="/bg/js/template-patcher.js"></script>
 <script src="/bg/js/template-renderer-proxy.js"></script>
 
 <script src="/bg/js/settings/keyboard-mouse-input-field.js"></script>