feat: support read the enabled status from the cssclasses field of property

Resolve: #5

common/data.ts

@@ -254,3 +254,30 @@ export function getBoolean(value: unknown) {
 
   return null;
 }
+
+/**
+ * Check if css string contains enable/disable heading classes.
+ *
+ * @param cssString CSS string.
+ * @param mode Mode to check for.
+ * @returns true if css string contains enable-${mode}-heading, false if it contains disable-${mode}-heading, and null otherwise.
+ */
+export function checkEnabledCss(
+  cssString: string,
+  mode: HeadingMetadataSettingsType
+) {
+  const cssClasses = cssString.split(" ").map((c) => c.trim());
+  for (const cssClass of cssClasses) {
+    switch (cssClass) {
+      case `enable-${mode}-heading`:
+        return true;
+      case `disable-${mode}-heading`:
+        return false;
+      case "enable-heading":
+        return true;
+      case "disable-heading":
+        return false;
+    }
+  }
+  return null; // default to null if no matching class is found
+}

main.ts

@@ -24,6 +24,7 @@ import {
   getOrderedCustomIdents,
   diffLevel,
   getBoolean,
+  checkEnabledCss,
 } from "./common/data";
 import { Counter, Querier } from "./common/counter";
 import { Heading } from "./common/heading";
@@ -556,8 +557,23 @@ export default class HeadingPlugin extends Plugin {
         return (
           getBoolean(metadataSettings[mode]) ?? getBoolean(metadataSettings.all)
         );
-      } else {
+      }
+      if (metadataSettings != null) {
         return getBoolean(metadataSettings);
+      } else {
+        const cssclasses = frontmatter.cssclasses;
+        if (Array.isArray(cssclasses)) {
+          for (const cssItem of cssclasses) {
+            if (typeof cssItem === "string") {
+              const s = checkEnabledCss(cssItem, mode);
+              if (s != null) {
+                return s;
+              }
+            }
+          }
+        } else if (typeof cssclasses === "string") {
+          return checkEnabledCss(cssclasses, mode);
+        }
       }
     }
 

test/common/data.spec.ts

@@ -1,6 +1,11 @@
 import "mocha";
 import { expect } from "chai";
-import { diffLevel, compareMarkdownText, getBoolean } from "../../common/data";
+import {
+  diffLevel,
+  compareMarkdownText,
+  getBoolean,
+  checkEnabledCss,
+} from "../../common/data";
 
 describe("common/data", function () {
   it("diffLevel", function () {
@@ -53,4 +58,37 @@ describe("common/data", function () {
     expect(getBoolean([])).to.be.null;
     expect(getBoolean({})).to.be.null;
   });
+
+  it("checkEnabledCss", function () {
+    expect(checkEnabledCss("", "reading")).to.be.null;
+    expect(checkEnabledCss("enable-preview-heading", "reading")).to.be.null;
+    expect(checkEnabledCss("enable-heading", "reading")).to.be.true;
+    expect(checkEnabledCss("disable-heading", "reading")).to.be.false;
+    expect(checkEnabledCss("enable-reading-heading", "reading")).to.be.true;
+    expect(checkEnabledCss("disable-reading-heading", "reading")).to.be.false;
+    expect(checkEnabledCss("enable-heading disable-heading", "reading")).to.be
+      .true;
+    expect(checkEnabledCss("disable-heading enable-heading", "reading")).to.be
+      .false;
+    expect(
+      checkEnabledCss(
+        "enable-reading-heading disable-reading-heading",
+        "reading"
+      )
+    ).to.be.true;
+    expect(
+      checkEnabledCss(
+        "disable-reading-heading enable-reading-heading",
+        "reading"
+      )
+    ).to.be.false;
+    expect(checkEnabledCss("enable-heading disable-reading-heading", "reading"))
+      .to.be.true;
+    expect(checkEnabledCss("disable-heading enable-reading-heading", "reading"))
+      .to.be.false;
+    expect(checkEnabledCss("enable-reading-heading disable-heading", "reading"))
+      .to.be.true;
+    expect(checkEnabledCss("disable-reading-heading enable-heading", "reading"))
+      .to.be.false;
+  });
 });