Allow templates to be tested on the settings page

ext/bg/css/settings.css

@@ -37,12 +37,6 @@ html:root:not([data-options-general-result-output-mode=merge]) #dict-main-group
     padding: 10px;
 }
 
-#field-templates {
-    font-family: monospace;
-    overflow-x: hidden;
-    white-space: pre;
-}
-
 .bottom-links {
     padding-bottom: 1em;
 }
@@ -136,14 +130,24 @@ html:root:not([data-options-general-result-output-mode=merge]) #dict-main-group
 }
 
 #custom-popup-css,
-#custom-popup-outer-css {
+#custom-popup-outer-css,
+#field-templates {
     width: 100%;
     min-height: 34px;
+    line-height: 18px;
     height: 96px;
     resize: vertical;
     font-family: 'Courier New', Courier, monospace;
     white-space: pre;
 }
+#field-templates {
+    height: 240px;
+    border-bottom-left-radius: 0;
+}
+#field-templates-reset {
+    border-top-left-radius: 0;
+    border-top-right-radius: 0;
+}
 
 .btn-inner-middle {
     vertical-align: middle;

ext/bg/js/dictionary.js

@@ -326,7 +326,7 @@ function dictFieldSplit(field) {
     return field.length === 0 ? [] : field.split(' ');
 }
 
-async function dictFieldFormat(field, definition, mode, options) {
+async function dictFieldFormat(field, definition, mode, options, exceptions) {
     const data = {
         marker: null,
         definition,
@@ -347,6 +347,7 @@ async function dictFieldFormat(field, definition, mode, options) {
         try {
             return await apiTemplateRender(options.anki.fieldTemplates, data, true);
         } catch (e) {
+            if (exceptions) { exceptions.push(e); }
             return `{${marker}-render-error}`;
         }
     });

ext/bg/js/settings.js

@@ -134,6 +134,8 @@ async function formWrite(options) {
     $('#screenshot-quality').val(options.anki.screenshot.quality);
     $('#field-templates').val(options.anki.fieldTemplates);
 
+    onAnkiTemplatesValidateCompile();
+
     try {
         await ankiDeckAndModelPopulate(options);
     } catch (e) {
@@ -144,7 +146,6 @@ async function formWrite(options) {
 }
 
 function formSetupEventListeners() {
-    $('#field-templates-reset').click(utilAsync(onAnkiFieldTemplatesReset));
     $('input, select, textarea').not('.anki-model').not('.ignore-form-changes *').change(utilAsync(onFormOptionsChanged));
     $('.anki-model').change(utilAsync(onAnkiModelChanged));
 }
@@ -202,6 +203,7 @@ async function onReady() {
     await audioSettingsInitialize();
     await profileOptionsSetup();
     await dictSettingsInitialize();
+    ankiTemplatesInitialize();
 
     storageInfoInitialize();
 
@@ -607,20 +609,105 @@ async function onAnkiModelChanged(e) {
     }
 }
 
-async function onAnkiFieldTemplatesReset(e) {
+function onAnkiFieldTemplatesReset(e) {
+    e.preventDefault();
+    $('#field-template-reset-modal').modal('show');
+}
+
+async function onAnkiFieldTemplatesResetConfirm(e) {
     try {
         e.preventDefault();
+
+        $('#field-template-reset-modal').modal('hide');
+
         const optionsContext = getOptionsContext();
         const options = await apiOptionsGet(optionsContext);
         const fieldTemplates = profileOptionsGetDefaultFieldTemplates();
         options.anki.fieldTemplates = fieldTemplates;
         $('#field-templates').val(fieldTemplates);
+        onAnkiTemplatesValidateCompile();
         await settingsSaveOptions();
     } catch (e) {
         ankiErrorShow(e);
     }
 }
 
+function ankiTemplatesInitialize() {
+    const markers = new Set(ankiGetFieldMarkers('terms').concat(ankiGetFieldMarkers('kanji')));
+    const fragment = ankiGetFieldMarkersHtml(markers);
+
+    const list = document.querySelector('#field-templates-list');
+    list.appendChild(fragment);
+    for (const node of list.querySelectorAll('.marker-link')) {
+        node.addEventListener('click', onAnkiTemplateMarkerClicked, false);
+    }
+
+    $('#field-templates').on('change', onAnkiTemplatesValidateCompile);
+    $('#field-template-render').on('click', onAnkiTemplateRender);
+    $('#field-templates-reset').on('click', onAnkiFieldTemplatesReset);
+    $('#field-templates-reset-confirm').on('click', onAnkiFieldTemplatesResetConfirm);
+}
+
+const ankiTemplatesValidateGetDefinition = (() => {
+    let cachedValue = null;
+    let cachedText = null;
+
+    return async (text, optionsContext) => {
+        if (cachedText !== text) {
+            const {definitions} = await apiTermsFind(text, optionsContext);
+            if (definitions.length === 0) { return null; }
+
+            cachedValue = definitions[0];
+            cachedText = text;
+        }
+        return cachedValue;
+    };
+})();
+
+async function ankiTemplatesValidate(infoNode, field, mode, showSuccessResult, invalidateInput) {
+    const text = document.querySelector('#field-templates-preview-text').value || '';
+    const exceptions = [];
+    let result = `No definition found for ${text}`;
+    try {
+        const optionsContext = getOptionsContext();
+        const definition = await ankiTemplatesValidateGetDefinition(text, optionsContext);
+        if (definition !== null) {
+            const options = await apiOptionsGet(optionsContext);
+            result = await dictFieldFormat(field, definition, mode, options, exceptions);
+        }
+    } catch (e) {
+        exceptions.push(e);
+    }
+
+    const hasException = exceptions.length > 0;
+    infoNode.hidden = !(showSuccessResult || hasException);
+    infoNode.textContent = hasException ? exceptions.map(e => `${e}`).join('\n') : (showSuccessResult ? result : '');
+    infoNode.classList.toggle('text-danger', hasException);
+    if (invalidateInput) {
+        const input = document.querySelector('#field-templates');
+        input.classList.toggle('is-invalid', hasException);
+    }
+}
+
+function onAnkiTemplatesValidateCompile() {
+    const infoNode = document.querySelector('#field-template-compile-result');
+    ankiTemplatesValidate(infoNode, '{expression}', 'term-kanji', false, true);
+}
+
+function onAnkiTemplateMarkerClicked(e) {
+    e.preventDefault();
+    document.querySelector('#field-template-render-text').value = `{${e.target.textContent}}`;
+}
+
+function onAnkiTemplateRender(e) {
+    e.preventDefault();
+
+    const field = document.querySelector('#field-template-render-text').value;
+    const infoNode = document.querySelector('#field-template-render-result');
+    infoNode.hidden = true;
+    ankiTemplatesValidate(infoNode, field, 'term-kanji', true, false);
+}
+
 
 /*
  * Storage

ext/bg/settings.html

@@ -272,7 +272,7 @@
 
                 <div class="form-group ignore-form-changes" style="display: none;" id="settings-popup-preview-settings">
                     <label for="settings-popup-preview-text">Popup preview text</label>
-                    <input type="text" id="settings-popup-preview-text" class="form-control" value="読め">
+                    <input type="text" id="settings-popup-preview-text" class="form-control" value="読め" placeholder="Preview text">
                 </div>
 
                 <div class="form-group ignore-form-changes">
@@ -699,10 +699,60 @@
                             <p class="help-block">
                                 Fields are formatted using the <a href="https://handlebarsjs.com/" target="_blank" rel="noopener">Handlebars.js</a> template rendering
                                 engine. Advanced users can modify these templates for ultimate control of what information gets included in
-                                their Anki cards. If you encounter problems with your changes you can always <a href="#" id="field-templates-reset">reset to default</a>
+                                their Anki cards. If you encounter problems with your changes, you can always reset to the default template settings.
-                                template settings.
                             </p>
                             <textarea autocomplete="off" spellcheck="false" wrap="soft" class="form-control" rows="10" id="field-templates"></textarea>
+                            <div>
+                                <button class="btn btn-danger" id="field-templates-reset">Reset Templates</button>
+                            </div>
+                            <p></p>
+                            <pre id="field-template-compile-result" hidden></pre>
+
+                            <p>Templates can be tested using the inputs below.</p>
+
+                            <div class="form-group">
+                                <div class="row">
+                                    <div class="col-xs-6">
+                                        <label for="field-templates-preview-text">Preview text</label>
+                                        <input type="text" id="field-templates-preview-text" class="form-control" value="読め" placeholder="Preview text">
+                                    </div>
+                                    <div class="col-xs-6">
+                                        <label for="field-template-render-text">Test field</label>
+                                        <div class="input-group">
+                                            <div class="input-group-btn">
+                                                <button class="btn btn-default" id="field-template-render" title="Test"><span class="glyphicon glyphicon-play"></span></button>
+                                            </div>
+                                            <input type="text" class="form-control" id="field-template-render-text" value="{expression}" placeholder="{marker}">
+                                            <div class="input-group-btn">
+                                                <button class="btn btn-default dropdown-toggle" id="field-templates-dropdown" data-toggle="dropdown"><span class="caret"></span></button>
+                                                <ul class="dropdown-menu dropdown-menu-right" id="field-templates-list"></ul>
+                                            </div>
+                                        </div>
+                                    </div>
+                                </div>
+                            </div>
+
+                            <p></p>
+                            <pre id="field-template-render-result" hidden></pre>
+                        </div>
+
+                        <div class="modal fade" tabindex="-1" role="dialog" id="field-template-reset-modal">
+                            <div class="modal-dialog modal-dialog-centered">
+                                <div class="modal-content">
+                                    <div class="modal-header">
+                                        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
+                                        <h4 class="modal-title">Confirm template reset</h4>
+                                    </div>
+                                    <div class="modal-body">
+                                        Are you sure you want to reset the field templates to the default value?
+                                        Any changes you made will be lost.
+                                    </div>
+                                    <div class="modal-footer">
+                                        <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>
+                                        <button type="button" class="btn btn-danger" id="field-templates-reset-confirm">Reset Templates</button>
+                                    </div>
+                                </div>
+                            </div>
                         </div>
 
                         <template id="anki-field-template"><tr>
@@ -777,6 +827,7 @@
         <script src="/mixed/lib/wanakana.min.js"></script>
 
         <script src="/mixed/js/extension.js"></script>
+        <script src="/mixed/js/japanese.js"></script>
 
         <script src="/bg/js/anki.js"></script>
         <script src="/bg/js/api.js"></script>