feat: Improved indentation when dragging tabs and folders (#9908)

* feat: Improved indentation when dragging tabs and folders

* fix: Formatting

src/browser/components/tabbrowser/content/tabbrowser-js.patch

@@ -1,5 +1,5 @@
 diff --git a/browser/components/tabbrowser/content/tabbrowser.js b/browser/components/tabbrowser/content/tabbrowser.js
-index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf76482a941 100644
+index d80a66a01002e78a9c65545d08fe786328ddf124..94497c80328551ac5bc14179bfc16722ec0c0158 100644
 --- a/browser/components/tabbrowser/content/tabbrowser.js
 +++ b/browser/components/tabbrowser/content/tabbrowser.js
 @@ -422,15 +422,60 @@
@@ -646,7 +646,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
            if (neighbor && this.isTab(element) && tabIndex > element._tPos) {
              neighbor.after(element);
            } else {
-@@ -6136,22 +6273,26 @@
+@@ -6136,22 +6273,23 @@
      #moveTabNextTo(element, targetElement, moveBefore = false, metricsContext) {
        if (this.isTabGroupLabel(targetElement)) {
          targetElement = targetElement.group;
@@ -667,9 +667,6 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
  
        // Don't allow mixing pinned and unpinned tabs.
 +      targetElement = gZenGlanceManager.getTabOrGlanceParent(targetElement);
-+      if (targetElement?.group?.hasAttribute("split-view-group")) {
-+        targetElement = targetElement.group;
-+      }
 +      if (element.hasAttribute('zen-essential') && !targetElement?.hasAttribute('zen-essential')) {
 +        targetElement = this.tabsWithoutGlance[this._numZenEssentials - 1];
 +      } else
@@ -679,7 +676,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
          moveBefore = false;
        } else if (!element.pinned && targetElement && targetElement.pinned) {
          // If the caller asks to move an unpinned element next to a pinned
-@@ -6165,14 +6306,18 @@
+@@ -6165,14 +6303,29 @@
          //    move the tab group right before the first unpinned tab.
          // 4. Moving a tab group and the first unpinned tab is grouped:
          //    move the tab group right before the first unpinned tab's tab group.
@@ -692,6 +689,17 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
        }
 +      if (!gZenFolders.canDropElement(element, targetElement)) {
 +        element = element.group;
++      }
++      // It is necessary to place the check below to avoid inserting an element
++      // inside when the split group is the last element.
++      if (targetElement?.group?.hasAttribute("split-view-group")) {
++        targetElement = targetElement.group;
++      }
++      // When the folder is the last element in the pinned section,
++      // targetElement is a tab with the zen-empty-tab attribute.
++      // If the movement is from top to bottom, it must be redefined as a folder.
++      if (targetElement?.hasAttribute("zen-empty-tab") && !moveBefore) {
++        targetElement = targetElement.group;
 +      }
  
        let getContainer = () =>
@@ -699,7 +707,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
          element.pinned
            ? this.tabContainer.pinnedTabsContainer
            : this.tabContainer;
-@@ -6181,7 +6326,7 @@
+@@ -6181,7 +6334,7 @@
          element,
          () => {
            if (moveBefore) {
@@ -708,7 +716,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
            } else if (targetElement) {
              targetElement.after(element);
            } else {
-@@ -6230,7 +6375,7 @@
+@@ -6230,7 +6383,7 @@
        if (!this.isTab(aTab)) {
          throw new Error("Can only move a tab into a tab group");
        }
@@ -717,7 +725,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
          return;
        }
        if (aTab.group && aTab.group.id === aGroup.id) {
-@@ -6324,6 +6469,10 @@
+@@ -6324,6 +6477,10 @@
  
        moveActionCallback();
  
@@ -728,7 +736,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
        // Clear tabs cache after moving nodes because the order of tabs may have
        // changed.
        this.tabContainer._invalidateCachedTabs();
-@@ -7221,7 +7370,7 @@
+@@ -7221,7 +7378,7 @@
              // preventDefault(). It will still raise the window if appropriate.
              break;
            }
@@ -737,7 +745,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
            window.focus();
            aEvent.preventDefault();
            break;
-@@ -8166,6 +8315,7 @@
+@@ -8166,6 +8323,7 @@
              aWebProgress.isTopLevel
            ) {
              this.mTab.setAttribute("busy", "true");
@@ -745,7 +753,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
              gBrowser._tabAttrModified(this.mTab, ["busy"]);
              this.mTab._notselectedsinceload = !this.mTab.selected;
            }
-@@ -9157,7 +9307,7 @@ var TabContextMenu = {
+@@ -9157,7 +9315,7 @@ var TabContextMenu = {
      );
      contextUnpinSelectedTabs.hidden =
        !this.contextTab.pinned || !this.multiselected;
@@ -754,7 +762,7 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
      // Build Ask Chat items
      TabContextMenu.GenAI.buildTabMenu(
        document.getElementById("context_askChat"),
-@@ -9476,6 +9626,7 @@ var TabContextMenu = {
+@@ -9476,6 +9634,7 @@ var TabContextMenu = {
          )
        );
      } else {
@@ -762,3 +770,4 @@ index d80a66a01002e78a9c65545d08fe786328ddf124..50ff735a4621110ff3691186139cabf7
        gBrowser.removeTab(this.contextTab, {
          animate: true,
          ...gBrowser.TabMetrics.userTriggeredContext(
+

src/browser/components/tabbrowser/content/tabgroup-js.patch

@@ -1,5 +1,5 @@
 diff --git a/browser/components/tabbrowser/content/tabgroup.js b/browser/components/tabbrowser/content/tabgroup.js
-index caea196b22b4689f55780a528661d87b52f4e728..ef687c6c693abab2b62023cfa7f44705acc5d04f 100644
+index caea196b22b4689f55780a528661d87b52f4e728..54f3be2b115f6b3691792796f758534aec90206d 100644
 --- a/browser/components/tabbrowser/content/tabgroup.js
 +++ b/browser/components/tabbrowser/content/tabgroup.js
 @@ -13,10 +13,12 @@
@@ -87,7 +87,7 @@ index caea196b22b4689f55780a528661d87b52f4e728..ef687c6c693abab2b62023cfa7f44705
      }
  
      get color() {
-@@ -338,12 +351,57 @@
+@@ -338,12 +351,61 @@
            tabGroupName,
          })
          .then(result => {
@@ -144,10 +144,14 @@ index caea196b22b4689f55780a528661d87b52f4e728..ef687c6c693abab2b62023cfa7f44705
 +        }
 +      }
 +      return true;
++    }
++
++    get level() {
++      return this.group?.level + 1 || 0;
      }
  
      /**
-@@ -373,7 +431,7 @@
+@@ -373,7 +435,7 @@
       */
      addTabs(tabs, metricsContext) {
        for (let tab of tabs) {
@@ -156,7 +160,7 @@ index caea196b22b4689f55780a528661d87b52f4e728..ef687c6c693abab2b62023cfa7f44705
            tab.ownerGlobal.gBrowser.unpinTab(tab);
          }
          let tabToMove =
-@@ -437,7 +495,7 @@
+@@ -437,7 +499,7 @@
       */
      on_click(event) {
        let isToggleElement =
@@ -165,10 +169,11 @@ index caea196b22b4689f55780a528661d87b52f4e728..ef687c6c693abab2b62023cfa7f44705
          event.target === this.#overflowCountLabel;
        if (isToggleElement && event.button === 0) {
          event.preventDefault();
-@@ -470,5 +528,6 @@
+@@ -470,5 +532,6 @@
      }
    }
  
 +  window.MozTabbrowserTabGroup = MozTabbrowserTabGroup;
    customElements.define("tab-group", MozTabbrowserTabGroup);
  }
+

src/browser/components/tabbrowser/content/tabs-js.patch

@@ -1,5 +1,5 @@
 diff --git a/browser/components/tabbrowser/content/tabs.js b/browser/components/tabbrowser/content/tabs.js
-index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb77ecf75a9 100644
+index e47f735e4e4563c9b7537944628418d1478c068d..858f6aa20bc06701facf75ee673f618464a406ab 100644
 --- a/browser/components/tabbrowser/content/tabs.js
 +++ b/browser/components/tabbrowser/content/tabs.js
 @@ -332,7 +332,7 @@
@@ -455,16 +455,19 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
  
        let newDropElementIndex;
        if (dropElement) {
-@@ -2856,7 +2936,7 @@
+@@ -2856,7 +2936,10 @@
        let shouldCreateGroupOnDrop;
        let dropBefore;
        if (dropElement) {
 -        let dropElementForOverlap = isTabGroupLabel(dropElement)
++        if (dropElement?.group?.hasAttribute("split-view-group") || dropElement.hasAttribute("split-view-group")) {
++          dropElement = dropElement.group.labelElement;
++        }
 +        let dropElementForOverlap = isTabGroupLabel(dropElement) && !dropElement.group?.hasAttribute("split-view-group")
            ? dropElement.parentElement
            : dropElement;
  
-@@ -2876,7 +2956,7 @@
+@@ -2876,7 +2959,7 @@
            ? Services.prefs.getIntPref(
                "browser.tabs.dragDrop.moveOverThresholdPercent"
              ) / 100
@@ -473,7 +476,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          moveOverThreshold = Math.min(1, Math.max(0, moveOverThreshold));
          let shouldMoveOver = overlapPercent > moveOverThreshold;
          if (logicalForward && shouldMoveOver) {
-@@ -2908,44 +2988,21 @@
+@@ -2908,44 +2991,21 @@
  
          // If dragging a group over another group, don't make it look like it is
          // possible to drop the dragged group inside the other group.
@@ -523,7 +526,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          // When dragging tab(s) over an ungrouped tab, signal to the user
          // that dropping the tab(s) will create a new tab group.
          shouldCreateGroupOnDrop =
-@@ -2955,12 +3012,6 @@
+@@ -2955,12 +3015,6 @@
            overlapPercent > dragOverGroupingThreshold;
  
          if (shouldCreateGroupOnDrop) {
@@ -536,7 +539,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          } else {
            this.removeAttribute("movingtab-createGroup");
            document
-@@ -2987,19 +3038,14 @@
+@@ -2987,19 +3041,14 @@
              dropElement = dropElementGroup;
              colorCode = undefined;
            } else if (isTabGroupLabel(dropElement)) {
@@ -564,7 +567,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
            }
            this.#setDragOverGroupColor(colorCode);
            this.toggleAttribute("movingtab-ungroup", !colorCode);
-@@ -3017,19 +3063,28 @@
+@@ -3017,19 +3066,28 @@
        dragData.dropElement = dropElement;
        dragData.dropBefore = dropBefore;
        dragData.animDropElementIndex = newDropElementIndex;
@@ -595,7 +598,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          }
          item.style.transform = transform;
        }
-@@ -3082,12 +3137,14 @@
+@@ -3082,12 +3140,14 @@
        );
      }
  
@@ -612,7 +615,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
  
        for (let item of this.ariaFocusableItems) {
          if (isTabGroupLabel(item)) {
-@@ -3095,6 +3152,18 @@
+@@ -3095,6 +3155,18 @@
            item = item.parentElement;
          }
          item.style.transform = "";
@@ -631,7 +634,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          item.removeAttribute("dragover-createGroup");
        }
        this.removeAttribute("movingtab-createGroup");
-@@ -3198,7 +3267,7 @@
+@@ -3198,7 +3270,7 @@
          let postTransitionCleanup = () => {
            movingTab._moveTogetherSelectedTabsData.animate = false;
          };
@@ -640,7 +643,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
            postTransitionCleanup();
          } else {
            let onTransitionEnd = transitionendEvent => {
-@@ -3371,7 +3440,7 @@
+@@ -3371,7 +3443,7 @@
      }
  
      _notifyBackgroundTab(aTab) {
@@ -649,7 +652,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
          return;
        }
  
-@@ -3480,7 +3549,10 @@
+@@ -3480,7 +3552,10 @@
      #getDragTarget(event, { ignoreSides = false } = {}) {
        let { target } = event;
        while (target) {
@@ -661,7 +664,7 @@ index e47f735e4e4563c9b7537944628418d1478c068d..1e821868ef0de97e19f46cc63ed03cb7
            break;
          }
          target = target.parentNode;
-@@ -3497,6 +3569,9 @@
+@@ -3497,6 +3572,9 @@
            return null;
          }
        }

src/zen/folders/ZenFolder.mjs

@@ -179,10 +179,6 @@
       return items;
     }
 
-    get level() {
-      return this.group?.level + 1 || 0;
-    }
-
     get allItems() {
       return [...this.querySelector('.tab-group-container').children].filter(
         (child) => !child.classList.contains('zen-tab-group-start')

src/zen/folders/ZenFolders.mjs

@@ -887,26 +887,30 @@
       return [];
     }
 
-    setFolderIndentation(tabs, group = undefined, forCollapse = true) {
+    setFolderIndentation(tabs, groupElem = undefined, forCollapse = true) {
       if (!gZenPinnedTabManager.expandedSidebarMode) {
         return;
       }
       const tab = tabs[0];
       let isTab = false;
-      if (!group && tab?.group) {
+      if (!groupElem && tab?.group) {
-        group = tab; // So we can set isTab later
+        groupElem = tab; // So we can set isTab later
       }
       if (
-        gBrowser.isTab(group) &&
+        gBrowser.isTab(groupElem) &&
-        !(group.hasAttribute('zen-empty-tab') && group.group === tab.group)
+        !(groupElem.hasAttribute('zen-empty-tab') && groupElem.group === tab.group)
       ) {
-        group = group.group;
+        groupElem = groupElem.group;
         isTab = true;
       }
-      if (!isTab && !group?.hasAttribute('selected') && !forCollapse) {
+      if (!isTab && !groupElem?.hasAttribute('selected') && !forCollapse) {
-        group = null; // Don't indent if the group is not selected
+        groupElem = null; // Don't indent if the group is not selected
+      }
+      let level = groupElem?.level + 1 || 0;
+      if (gBrowser.isTabGroupLabel(groupElem)) {
+        // If it is a group label, we should not increase its level by one.
+        level = groupElem.group.level;
       }
-      const level = group?.level + 1 || 0;
       const baseSpacing = 14; // Base spacing for each level
       let tabToAnimate = tab;
       if (gBrowser.isTabGroupLabel(tab)) {
@@ -1348,10 +1352,11 @@
       let dragDownThreshold =
         Services.prefs.getIntPref('zen.view.drag-and-drop.drop-inside-lower-threshold') / 100;
 
-      let dropElementGroup = dropElement.group;
+      const dropElementGroup = dropElement.group;
       const isSplitGroup = dropElement?.group?.hasAttribute('split-view-group');
       let firstGroupElem =
         dropElementGroup.querySelector('.zen-tab-group-start').nextElementSibling;
+      if (gBrowser.isTabGroup(firstGroupElem)) firstGroupElem = firstGroupElem.labelElement;
 
       const isRestrictedGroup = isSplitGroup || dropElementGroup.collapsed;
 
@@ -1368,16 +1373,11 @@
         this.highlightGroupOnDragOver(dropElementGroup, movingTabs);
       } else if (shouldDropNear) {
         if (dropBefore) {
-          dropElement = dropElementGroup;
           colorCode = undefined;
-        } else {
+        } else if (!isRestrictedGroup) {
-          if (isRestrictedGroup) {
-            dropElement = dropElementGroup;
-          } else {
           dropElement = firstGroupElem;
           dropBefore = true;
         }
-        }
         this.highlightGroupOnDragOver(null);
       }