Improve logic for adjusting correction panel dimensions to support inline elements

This is still a WIP commit, hence the code is yet to be refactored eventually

service.js

@@ -275,21 +275,35 @@ class BesService {
     return rect.left <= x && x < rect.right && rect.top <= y && y < rect.bottom
   }
 
+  // TODO: Monitor if hostElement moves in DOM and reposition correction panel and status icon.
   /**
    * Creates auxiliary DOM elements for text adornments.
    */
   createCorrectionPanel() {
     const panelParent = document.createElement('div')
     panelParent.classList.add('bes-correction-panel-parent')
+
     this.correctionPanel = document.createElement('div')
-    this.scrollPanel = document.createElement('div')
-    this.setCorrectionPanelSize()
     this.correctionPanel.classList.add('bes-correction-panel')
+
+    this.scrollPanel = document.createElement('div')
     this.scrollPanel.classList.add('bes-correction-panel-scroll')
 
-    this.correctionPanel.appendChild(this.scrollPanel)
     panelParent.appendChild(this.correctionPanel)
+    this.correctionPanel.appendChild(this.scrollPanel)
+    // Inline elements (textarea) and CKEditor.
+    if (
+      this.hostElement.tagName !== 'DIV' ||
+      this.hostElement.classList.contains('ck-editor__editable')
+    ) {
       this.textElement.parentElement.insertBefore(panelParent, this.textElement)
+      this.setCorrectionPanelSize()
+    }
+    // Block elements (contenteditable = 'true', readonly). This also works correctly if DIV element has display set to inline-block.
+    else {
+      document.body.insertBefore(panelParent, document.body.firstChild)
+      this.setCorrectionPanelSize()
+    }
 
     this.statusDiv = document.createElement('div')
     this.statusDiv.classList.add('bes-status-div')
@@ -323,20 +337,40 @@ class BesService {
    */
   setCorrectionPanelSize() {
     const styles = window.getComputedStyle(this.textElement)
-
-    this.correctionPanel.style.width = styles.width
     this.correctionPanel.style.marginLeft = styles.marginLeft
     this.correctionPanel.style.marginRight = styles.marginRight
     this.correctionPanel.style.paddingLeft = styles.paddingLeft
     this.correctionPanel.style.paddingRight = styles.paddingRight
     this.scrollPanel.style.width = `${this.textElement.scrollWidth}px`
+    if (
+      this.hostElement.tagName !== 'DIV' ||
+      this.hostElement.classList.contains('ck-editor__editable')
+    ) {
+      const hStyles = window.getComputedStyle(this.hostElement)
+      const totalWidth =
+        parseFloat(styles.paddingLeft) +
+        parseFloat(styles.marginLeft) +
+        parseFloat(styles.width) +
+        parseFloat(styles.marginRight) +
+        parseFloat(styles.paddingRight)
+      this.correctionPanel.style.width = `${totalWidth}px`
+      this.correctionPanel.style.height = hStyles.height
 
-    this.correctionPanel.style.height = styles.height
-    this.correctionPanel.style.marginTop = styles.marginTop
-    this.correctionPanel.style.marginBottom = styles.marginBottom
-    this.correctionPanel.style.paddingTop = styles.paddingTop
-    this.correctionPanel.style.paddingBottom = styles.paddingBottom
       this.scrollPanel.style.height = `${this.textElement.scrollHeight}px`
+    } else {
+      const rect = this.textElement.getBoundingClientRect()
+      this.correctionPanel.style.width = styles.width
+
+      const totalHeight =
+        parseFloat(styles.paddingTop) +
+        parseFloat(styles.marginTop) +
+        parseFloat(styles.height) +
+        parseFloat(styles.marginBottom) +
+        parseFloat(styles.paddingBottom)
+      this.correctionPanel.style.height = `${totalHeight}px`
+      this.correctionPanel.style.marginTop = `${rect.top + window.scrollY}px`
+      this.scrollPanel.style.height = `${this.textElement.scrollHeight}px`
+    }
   }
 
   /**