From 9a6efc0403f00c72a32eea601119673f2cfdbc6c Mon Sep 17 00:00:00 2001
From: GabrielMeyer <meyergabriel@live.de>
Date: Mon, 26 Aug 2019 12:00:23 +0200
Subject: [PATCH] Adds a handler for 'sorting-tree's

- Also fixes drag-handling for mobile-devices.
---
 .../sorting-tree/sorting-tree.component.html  | 94 +++++++++----------
 .../sorting-tree/sorting-tree.component.scss  | 12 ++-
 .../sorting-tree/sorting-tree.component.ts    | 58 ++++++++----
 3 files changed, 97 insertions(+), 67 deletions(-)

diff --git a/client/src/app/shared/components/sorting-tree/sorting-tree.component.html b/client/src/app/shared/components/sorting-tree/sorting-tree.component.html
index f1cbe3584..6959158f9 100644
--- a/client/src/app/shared/components/sorting-tree/sorting-tree.component.html
+++ b/client/src/app/shared/components/sorting-tree/sorting-tree.component.html
@@ -1,47 +1,47 @@
-    <cdk-tree
-        #osTree="cdkDropList"
-        [dataSource]="dataSource"
-        [treeControl]="treeControl"
-        cdkDropList
-        [cdkDropListData]="osTreeData"
-        (cdkDropListSorted)="sortItems($event)"
-        >
-
-        <cdk-tree-node
-            cdkDrag
-            [cdkDragData]="node"
-            (cdkDragDropped)="onDrop(node)"
-            (mousedown)="mouseDown($event)"
-            (mouseup)="mouseUp($event)"
-            (cdkDragStarted)="startsDrag($event)"
-            (cdkDragMoved)="moveItem($event)"
-            *cdkTreeNodeDef="let node"
-            [style.display]="shouldRender(node) ? 'flex' : 'none'"
-            [style.padding-left]="node.level * 40 + 'px'">
-            <div class="backgroundColorLight">
-                <button
-                    *ngIf="!hasChild"
-                    mat-icon-button
-                    disabled></button>
-                <button
-                    *ngIf="hasChild"
-                    mat-icon-button
-                    cdkTreeNodeToggle
-                    [attr.aria-label]="'toggle ' + node.filename"
-                    (click)="handleClick(node, true)"
-                    [style.visibility]="node.expandable ? 'visible' : 'hidden'">
-                    <mat-icon
-                        [style.transform]="node.isExpanded ? 'rotate(90deg)' : 'rotate(0deg)'"
-                        class="mat-icon-rtl-mirror">
-                        chevron_right
-                    </mat-icon>
-                </button>
-                <ng-container
-                    [ngTemplateOutlet]="innerNode"
-                    [ngTemplateOutletContext]="{item: node.item}"></ng-container>
-            </div>
-            <div
-            [style.margin-left]="placeholderLevel * 40 + 'px'"
-            *cdkDragPlaceholder></div>
-        </cdk-tree-node>
-    </cdk-tree>
+<cdk-tree
+    #osTree="cdkDropList"
+    [dataSource]="dataSource"
+    [treeControl]="treeControl"
+    cdkDropList
+    [cdkDropListData]="osTreeData"
+    (cdkDropListSorted)="sortItems($event)"
+>
+    <cdk-tree-node
+        cdkDrag
+        [cdkDragData]="node"
+        (cdkDragDropped)="onDrop(node)"
+        (mousedown)="mouseDown($event)"
+        (mouseup)="mouseUp()"
+        (touchstart)="touchStart($event)"
+        (touchend)="mouseUp()"
+        (cdkDragStarted)="startsDrag($event)"
+        (cdkDragMoved)="moveItem($event)"
+        *cdkTreeNodeDef="let node"
+        [style.display]="shouldRender(node) ? 'flex' : 'none'"
+        [style.padding-left]="node.level * 40 + 'px'"
+    >
+        <div class="backgroundColorLight">
+            <span cdkDragHandle>
+                <mat-icon>drag_indicator</mat-icon>
+            </span>
+            <button *ngIf="!hasChild" mat-icon-button disabled></button>
+            <button
+                *ngIf="hasChild"
+                mat-icon-button
+                cdkTreeNodeToggle
+                [attr.aria-label]="'toggle ' + node.filename"
+                (click)="handleClick(node, true)"
+                [style.visibility]="node.expandable ? 'visible' : 'hidden'"
+            >
+                <mat-icon
+                    [style.transform]="node.isExpanded ? 'rotate(90deg)' : 'rotate(0deg)'"
+                    class="mat-icon-rtl-mirror"
+                >
+                    chevron_right
+                </mat-icon>
+            </button>
+            <ng-container [ngTemplateOutlet]="innerNode" [ngTemplateOutletContext]="{ item: node.item }"></ng-container>
+        </div>
+        <div [style.margin-left]="placeholderLevel * 40 + 'px'" *cdkDragPlaceholder></div>
+    </cdk-tree-node>
+</cdk-tree>
diff --git a/client/src/app/shared/components/sorting-tree/sorting-tree.component.scss b/client/src/app/shared/components/sorting-tree/sorting-tree.component.scss
index 9f13ad79b..ca9b078df 100644
--- a/client/src/app/shared/components/sorting-tree/sorting-tree.component.scss
+++ b/client/src/app/shared/components/sorting-tree/sorting-tree.component.scss
@@ -8,7 +8,6 @@
         margin: 3px 0;
         display: flex;
         align-items: center;
-        cursor: pointer;
 
         div {
             display: inherit;
@@ -21,13 +20,22 @@
         }
     }
 
+    // Overwrite the handler
+    .cdk-drag-handle {
+        display: flex;
+        cursor: move;
+        width: 50px;
+        align-items: center;
+        justify-content: center;
+    }
+
     // Overwrite the preview
     .cdk-drag-preview {
         box-shadow: none !important;
         background-color: unset !important;
         border-radius: 6px !important;
 
-        div {
+        div.backgroundColorLight {
             box-sizing: border-box;
             background-color: mat-color($background, background);
             border-radius: 4px;
diff --git a/client/src/app/shared/components/sorting-tree/sorting-tree.component.ts b/client/src/app/shared/components/sorting-tree/sorting-tree.component.ts
index 02ee7954c..f9d12b32c 100644
--- a/client/src/app/shared/components/sorting-tree/sorting-tree.component.ts
+++ b/client/src/app/shared/components/sorting-tree/sorting-tree.component.ts
@@ -480,22 +480,38 @@ export class SortingTreeComponent<T extends Identifiable & Displayable> implemen
         this.calcNextPosition();
     }
 
+    /**
+     * Initializes the `this.pointer` with the x- and y-coordinates,
+     * where the user starts the dragging.
+     *
+     * @param x The value of the x-position on screen.
+     * @param y The value of the y-position on screen.
+     */
+    private initPointer(x: number, y: number): void {
+        this.pointer = {
+            position: {
+                x,
+                y
+            },
+            currentPosition: {
+                x,
+                y
+            }
+        };
+    }
+
     /**
      * Function to set the cursor position immediately if the user starts dragging a node.
      *
      * @param event The mouse event which emits the event.
      */
     public mouseDown(event: MouseEvent): void {
-        this.pointer = {
-            position: {
-                x: event.x,
-                y: event.y
-            },
-            currentPosition: {
-                x: event.x,
-                y: event.y
-            }
-        };
+        this.initPointer(event.x, event.y);
+    }
+
+    public touchStart(event: TouchEvent): void {
+        const { clientX, clientY }: { clientX: number; clientY: number } = event.touches[0];
+        this.initPointer(Math.round(clientX), Math.round(clientY));
     }
 
     /**
@@ -551,16 +567,22 @@ export class SortingTreeComponent<T extends Identifiable & Displayable> implemen
      */
     private getDirection(): Movement {
         const movement = new Movement();
-        movement.verticalMove =
-            this.nextNode.startPosition < this.nextNode.nextPosition
-                ? Direction.DOWNWARDS
-                : this.nextNode.startPosition > this.nextNode.nextPosition
-                ? Direction.UPWARDS
-                : Direction.NOWAY;
+        if (this.nextNode.startPosition < this.nextNode.nextPosition) {
+            movement.verticalMove = Direction.DOWNWARDS;
+        } else if (this.nextNode.startPosition > this.nextNode.nextPosition) {
+            movement.verticalMove = Direction.UPWARDS;
+        } else {
+            movement.verticalMove = Direction.NOWAY;
+        }
         const deltaX = this.pointer.currentPosition.x - this.pointer.position.x;
         movement.steps = Math.trunc(deltaX / 40);
-        movement.horizontalMove =
-            movement.steps > 0 ? Direction.RIGHT : movement.steps < 0 ? Direction.LEFT : Direction.NOWAY;
+        if (movement.steps > 0) {
+            movement.horizontalMove = Direction.RIGHT;
+        } else if (movement.steps < 0) {
+            movement.horizontalMove = Direction.LEFT;
+        } else {
+            movement.horizontalMove = Direction.NOWAY;
+        }
         return movement;
     }