#225 - Placeholder support for front matter field values (template and content type)

package.json

@@ -198,6 +198,30 @@
           },
           "scope": "Content"
         },
+        "frontMatter.content.placeholders": {
+          "type": "array",
+          "default": [],
+          "markdownDescription": "This array of placeholders defines the placeholders that you can use in your content types and templates for automatically populating your content its front matter. [Check in the docs](https://frontmatter.codes/docs/settings#frontmatter.content.placeholders)",
+          "items": {
+            "type": "object",
+            "properties": {
+              "id": {
+                "type": "string",
+                "description": "ID of the placeholder, in your content type or template, use it as follows: {{placeholder}}"
+              },
+              "value": {
+                "type": "string",
+                "description": "The placeholder its value"
+              }
+            },
+            "additionalProperties": false,
+            "required": [
+              "id",
+              "value"
+            ]
+          },
+          "scope": "Content"
+        },
         "frontMatter.content.publicFolder": {
           "type": "string",
           "default": "",

src/commands/Template.ts

@@ -159,13 +159,7 @@ export class Template {
     }
 
     if (frontMatter.data) {
-      const fmData = frontMatter.data;
-      if (typeof fmData.title !== "undefined") {
-        fmData.title = titleValue;
-      }
-      if (typeof fmData.slug !== "undefined") {
-        fmData.slug = ArticleHelper.sanitize(titleValue);
-      }
+      frontMatter.data = ArticleHelper.updatePlaceholders(frontMatter.data, titleValue);
 
       frontMatter = Article.updateDate(frontMatter);
 

src/constants/settings.ts

@@ -46,6 +46,7 @@ export const SETTINGS_CONTENT_FRONTMATTER_HIGHLIGHT = "content.fmHighlight";
 export const SETTINGS_CONTENT_DRAFT_FIELD = "content.draftField";
 export const SETTINGS_CONTENT_SORTING = "content.sorting";
 export const SETTINGS_CONTENT_WYSIWYG = "content.wysiwyg";
+export const SETTINGS_CONTENT_PLACEHOLDERS = "content.placeholders";
 
 export const SETTINGS_CONTENT_SORTING_DEFAULT = "content.defaultSorting";
 export const SETTINGS_MEDIA_SORTING_DEFAULT = "content.defaultSorting";

src/helpers/ArticleHelper.ts

@@ -3,7 +3,7 @@ import { DEFAULT_CONTENT_TYPE, DEFAULT_CONTENT_TYPE_NAME } from './../constants/
 import * as vscode from 'vscode';
 import * as matter from "gray-matter";
 import * as fs from "fs";
-import { DefaultFields, SETTINGS_CONTENT_DEFAULT_FILETYPE, SETTING_COMMA_SEPARATED_FIELDS, SETTING_DATE_FIELD, SETTING_DATE_FORMAT, SETTING_INDENT_ARRAY, SETTING_REMOVE_QUOTES, SETTING_TAXONOMY_CONTENT_TYPES, SETTING_TEMPLATES_PREFIX } from '../constants';
+import { DefaultFields, SETTINGS_CONTENT_DEFAULT_FILETYPE, SETTINGS_CONTENT_PLACEHOLDERS, SETTING_COMMA_SEPARATED_FIELDS, SETTING_DATE_FIELD, SETTING_DATE_FORMAT, SETTING_INDENT_ARRAY, SETTING_REMOVE_QUOTES, SETTING_TAXONOMY_CONTENT_TYPES, SETTING_TEMPLATES_PREFIX } from '../constants';
 import { DumpOptions } from 'js-yaml';
 import { TomlEngine, getFmLanguage, getFormatOpts } from './TomlEngine';
 import { Extension, Settings } from '.';
@@ -274,6 +274,78 @@ export class ArticleHelper {
     return newFilePath;
   }
 
+  /**
+   * Update placeholder values in the front matter content
+   * @param data 
+   * @param title 
+   * @returns 
+   */
+  public static updatePlaceholders(data: any, title: string) {
+    const fmData = Object.assign({}, data);
+
+    for (const fieldName of Object.keys(fmData)) {
+      const fieldValue = fmData[fieldName];
+
+      if (fieldName === "title" && (fieldValue === null || fieldValue === "")) {
+        fmData[fieldName] = title;
+      }
+  
+      if (fieldName === "slug" && (fieldValue === null || fieldValue === "")) {
+        fmData[fieldName] = ArticleHelper.sanitize(title);
+      }
+
+      fmData[fieldName] = this.processKnownPlaceholders(fmData[fieldName], title);
+      fmData[fieldName] = this.processCustomPlaceholders(fmData[fieldName], title);
+    }
+
+    return fmData;
+  }
+
+  /**
+   * Replace the known placeholders
+   * @param value 
+   * @param title 
+   * @returns 
+   */
+  public static processKnownPlaceholders(value: string, title: string) {
+    if (value && typeof value === "string") {
+      if (value.includes("{{title}}")) {
+        const regex = new RegExp("{{title}}", "g");
+        value = value.replace(regex, title);
+      }
+      
+      if (value.includes("{{slug}}")) {
+        const regex = new RegExp("{{slug}}", "g");
+        value = value.replace(regex, ArticleHelper.sanitize(title));
+      }
+    }
+
+    return value;
+  }
+
+  /**
+   * Replace the custom placeholders
+   * @param value 
+   * @param title 
+   * @returns 
+   */
+  public static processCustomPlaceholders(value: string, title: string) {
+    if (value && typeof value === "string") {
+      const placeholders = Settings.get<{id: string, value: string}[]>(SETTINGS_CONTENT_PLACEHOLDERS);
+      if (placeholders && placeholders.length > 0) {
+        for (const placeholder of placeholders) {
+          if (value.includes(`{{${placeholder.id}}}`)) {
+            const regex = new RegExp(`{{${placeholder.id}}}`, "g");
+            const updatedValue = this.processKnownPlaceholders(placeholder.value, title);
+            value = value.replace(regex, updatedValue);
+          }
+        }
+      }
+    }
+
+    return value;
+  }
+
   /**
    * Parse a markdown file and its front matter
    * @param fileContents 

src/helpers/ContentType.ts

@@ -135,15 +135,22 @@ export class ContentType {
    * @param data 
    */
   private static processFields(obj: IContentType | Field, titleValue: string, data: any) {
+    
     if (obj.fields) {
       for (const field of obj.fields) {
         if (field.name === "title") {
-          data[field.name] = titleValue;
+          if (field.default) {
+            data[field.name] = ArticleHelper.processKnownPlaceholders(field.default, titleValue);
+            data[field.name] = ArticleHelper.processCustomPlaceholders(data[field.name], titleValue);
+          } else {
+            data[field.name] = titleValue;
+          }
         } else {
           if (field.type === "fields") {
             data[field.name] = this.processFields(field, titleValue, {});
           } else {
-            data[field.name] = field.default || "";
+            data[field.name] = field.default ? ArticleHelper.processKnownPlaceholders(field.default, titleValue) : "";
+            data[field.name] = field.default ? ArticleHelper.processCustomPlaceholders(data[field.name], titleValue) : "";
           }
         }
       }