Redesign difficulty adjustment dashboard widget

frontend/src/app/components/difficulty/difficulty-tooltip.component.ts

@@ -0,0 +1,66 @@
+import { Component, ElementRef, ViewChild, Input, OnChanges } from '@angular/core';
+
+interface EpochProgress {
+  base: string;
+  change: number;
+  progress: number;
+  minedBlocks: number;
+  remainingBlocks: number;
+  expectedBlocks: number;
+  newDifficultyHeight: number;
+  colorAdjustments: string;
+  colorPreviousAdjustments: string;
+  estimatedRetargetDate: number;
+  previousRetarget: number;
+  blocksUntilHalving: number;
+  timeUntilHalving: number;
+}
+
+const EPOCH_BLOCK_LENGTH = 2016; // Bitcoin mainnet
+
+@Component({
+  selector: 'app-difficulty-tooltip',
+  templateUrl: './difficulty-tooltip.component.html',
+  styleUrls: ['./difficulty-tooltip.component.scss'],
+})
+export class DifficultyTooltipComponent implements OnChanges {
+  @Input() status: string | void;
+  @Input() progress: EpochProgress | void = null; 
+  @Input() cursorPosition: { x: number, y: number };
+
+  mined: number;
+  ahead: number;
+  behind: number;
+  expected: number;
+  remaining: number;
+  isAhead: boolean;
+  isBehind: boolean;
+
+  tooltipPosition = { x: 0, y: 0 };
+
+  @ViewChild('tooltip') tooltipElement: ElementRef<HTMLCanvasElement>;
+
+  constructor() {}
+
+  ngOnChanges(changes): void {
+    if (changes.cursorPosition && changes.cursorPosition.currentValue) {
+      let x = changes.cursorPosition.currentValue.x;
+      let y = changes.cursorPosition.currentValue.y - 50;
+      if (this.tooltipElement) {
+        const elementBounds = this.tooltipElement.nativeElement.getBoundingClientRect();
+        x -= elementBounds.width / 2;
+        x = Math.min(Math.max(x, 20), (window.innerWidth - 20 - elementBounds.width));
+      }
+      this.tooltipPosition = { x, y };
+    }
+    if ((changes.progress || changes.status) && this.progress && this.status) {
+      this.remaining = this.progress.remainingBlocks;
+      this.expected = this.progress.expectedBlocks;
+      this.mined = this.progress.minedBlocks;
+      this.ahead = Math.max(0, this.mined - this.expected);
+      this.behind = Math.max(0, this.expected - this.mined);
+      this.isAhead = this.ahead > 0;
+      this.isBehind = this.behind > 0;
+    }
+  }
+}