refactor: add new auto arrangement method and improved demo changes

Author: sheikalthaf

projects/flow/README.md

@@ -1,7 +1,7 @@
 # Angular Flow
 
 Angular Flow is a component that allows you to create a flow diagram using Angular.
-Live Demo [link](https://sheikalthaf.github.io/flow/)
+Live Demo [link](https://uiuniversal.github.io/flow/)
 
 Stackblitz Demo [link](https://stackblitz.com/edit/ngu-flow)
 

projects/flow/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@ngu/flow",
-  "version": "0.0.3",
+  "version": "0.0.4",
   "peerDependencies": {
     "@angular/common": "^14.0.0",
     "@angular/core": "^14.0.0"

projects/flow/src/lib/arrangements.spec.ts

@@ -1,4 +1,4 @@
-import { Arrangements } from './arrangements';
+import { Arrangements, Arrangements2 } from './arrangements';
 import { ChildInfo } from './flow-interface';
 
 export const FLOW_LIST = [
@@ -38,3 +38,30 @@ describe('Arrangements', () => {
     expect(actual).toEqual(expected);
   });
 });
+
+describe('Arrangements2', () => {
+  let arrangements: Arrangements2;
+
+  it('should be created', () => {
+    const childObj: ChildInfo[] = FLOW_LIST.map((x) => ({
+      position: x,
+      elRect: { width: 200, height: 200 } as any,
+    }));
+
+    arrangements = new Arrangements2(childObj);
+    arrangements.verticalPadding = 20;
+    arrangements.groupPadding = 100;
+    const expected = {
+      '1': { x: 330, y: 0, id: '1', deps: [] },
+      '2': { x: 110, y: 300, id: '2', deps: ['1'] },
+      '3': { x: 0, y: 600, id: '3', deps: ['2'] },
+      '4': { x: 220, y: 600, id: '4', deps: ['2'] },
+      '5': { x: 550, y: 300, id: '5', deps: ['1'] },
+      '6': { x: 440, y: 600, id: '6', deps: ['5'] },
+      '7': { x: 660, y: 600, id: '7', deps: ['5'] },
+      '8': { x: 660, y: 900, id: '8', deps: ['6', '7'] },
+    };
+    const actual = Object.fromEntries(arrangements.autoArrange());
+    expect(actual).toEqual(expected);
+  });
+});

projects/flow/src/lib/arrangements.ts

@@ -1,4 +1,4 @@
-import { FlowOptions, ChildInfo } from './flow-interface';
+import { FlowOptions, ChildInfo, FlowDirection } from './flow-interface';
 
 export class Arrangements {
   constructor(
@@ -21,12 +21,12 @@ export class Arrangements {
 
     for (const baseNode of baseNodes) {
       if (this.direction === 'horizontal') {
-        this.positionDependents(baseNode, currentX, 0, newItems);
-        currentX += baseNode.elRect.width + this.horizontalPadding;
+        this.positionDependents(baseNode, 0, currentY, newItems);
+        currentY += baseNode.elRect.height + this.verticalPadding;
       } else {
         // Vertical arrangement
-        this.positionDependents(baseNode, 0, currentY, newItems);
-        currentY += baseNode.elRect.height + this.horizontalPadding;
+        this.positionDependents(baseNode, 0, currentX, newItems);
+        currentX += baseNode.elRect.width + this.verticalPadding;
       }
     }
 
@@ -116,3 +116,110 @@ export class Arrangements {
     return { consumedSpace, dep: dependents.length > 0 };
   }
 }
+
+const ROOT_DATA = new Map<string, ArrangeNode>();
+const ROOT_DEPS = new Map<string, string[]>();
+const HORIZONTAL_PADDING = 100;
+const VERTICAL_PADDING = 20;
+
+export class Arrangements2 {
+  root: string[] = [];
+
+  constructor(
+    private list: ChildInfo[],
+    private direction: FlowDirection = 'vertical',
+    public horizontalPadding = 100,
+    public verticalPadding = 20,
+    public groupPadding = 20
+  ) {
+    ROOT_DATA.clear();
+    ROOT_DEPS.clear();
+    this.list.forEach((item) => {
+      ROOT_DATA.set(
+        item.position.id,
+        new ArrangeNode(item.position, item.elRect)
+      );
+      item.position.deps.forEach((dep) => {
+        let d = ROOT_DEPS.get(dep) || [];
+        d.push(item.position.id);
+        ROOT_DEPS.set(dep, d);
+      });
+
+      if (item.position.deps.length === 0) {
+        this.root.push(item.position.id);
+      }
+    });
+  }
+
+  public autoArrange(): Map<string, FlowOptions> {
+    this.root.forEach((id) => {
+      const node = ROOT_DATA.get(id)!;
+      node.arrange(0, 0, this.direction);
+    });
+
+    const newItems = new Map<string, FlowOptions>();
+
+    for (const item of this.list) {
+      newItems.set(item.position.id, item.position);
+    }
+    return newItems;
+  }
+}
+
+interface Coordinates {
+  x: number;
+  y: number;
+}
+
+export class ArrangeNode {
+  constructor(public position: FlowOptions, public elRect: DOMRect) {}
+
+  get deps() {
+    return ROOT_DEPS.get(this.position.id) || [];
+  }
+
+  // we need to recursively call this method to get all the dependents of the node
+  // and then we need to position them
+  arrange(x = 0, y = 0, direction: FlowDirection): Coordinates {
+    const dependents = ROOT_DEPS.get(this.position.id) || [];
+    let startX = x;
+    let startY = y;
+    let len = dependents.length;
+
+    if (len) {
+      if (direction === 'horizontal') {
+        startX += this.elRect.width + HORIZONTAL_PADDING;
+      } else {
+        startY += this.elRect.height + HORIZONTAL_PADDING;
+      }
+      let first, last: Coordinates;
+      for (let i = 0; i < len; i++) {
+        const dep = dependents[i];
+        const dependent = ROOT_DATA.get(dep)!;
+        const { x, y } = dependent.arrange(startX, startY, direction);
+        // capture the first and last dependent
+        if (i === 0) first = dependent.position;
+        if (i === len - 1) last = dependent.position;
+
+        if (direction === 'horizontal') {
+          startY = y + VERTICAL_PADDING;
+        } else {
+          startX = x + VERTICAL_PADDING;
+        }
+      }
+      if (direction === 'horizontal') {
+        startY -= VERTICAL_PADDING + this.elRect.height;
+        y = first!.y + (last!.y - first!.y) / 2;
+      } else {
+        startX -= VERTICAL_PADDING + this.elRect.width;
+        x = first!.x + (last!.x - first!.x) / 2;
+      }
+    }
+    this.position.x = x;
+    this.position.y = y;
+
+    return direction === 'horizontal'
+      ? { x: startX, y: startY + this.elRect.height }
+      : { x: startX + this.elRect.width, y: startY };
+  }
+}

projects/flow/src/lib/flow-child.component.ts

@@ -12,7 +12,6 @@ import {
   SimpleChanges,
   ChangeDetectionStrategy,
 } from '@angular/core';
-import { takeUntilDestroyed } from '@angular/core/rxjs-interop';
 import { Subject, Subscription } from 'rxjs';
 import { FlowService } from './flow.service';
 import { FlowOptions } from './flow-interface';
@@ -70,6 +69,7 @@ export class FlowChildComponent implements OnInit, OnChanges, OnDestroy {
 
   private positionChange = new Subject<FlowOptions>();
   private mouseMoveSubscription: Subscription;
+  private layoutSubscribe: Subscription;
 
   constructor(
     public el: ElementRef<HTMLDivElement>,
@@ -89,7 +89,7 @@ export class FlowChildComponent implements OnInit, OnChanges, OnDestroy {
       });
     });
 
-    this.flow.layoutUpdated.pipe(takeUntilDestroyed()).subscribe((x) => {
+    this.layoutSubscribe = this.flow.layoutUpdated.subscribe((x) => {
       this.position = this.flow.items.get(this.position.id) as FlowOptions;
       this.positionChange.next(this.position);
     });
@@ -171,6 +171,7 @@ export class FlowChildComponent implements OnInit, OnChanges, OnDestroy {
 
   ngOnDestroy() {
     this.disableDragging();
+    this.layoutSubscribe.unsubscribe();
     // remove the FlowOptions from the flow service
     // this.flow.delete(this.position);
     // console.log('ngOnDestroy', this.position.id);

projects/flow/src/lib/flow-interface.ts

@@ -12,7 +12,27 @@ export interface FlowOptions {
   deps: string[];
 }
 
+export interface DotOptions extends FlowOptions {
+  /**
+   * The index of the dot
+   * top = 0
+   * right = 1
+   * bottom = 2
+   * left = 3
+   */
+  dotIndex: number;
+}
+
 export class FlowConfig {
   Arrows = true;
   ArrowSize = 20;
 }
+
+export type FlowDirection = 'horizontal' | 'vertical';
+
+export type ArrowPathFn = (
+  start: DotOptions,
+  end: DotOptions,
+  arrowSize: number,
+  strokeWidth: number
+) => string;