Added timer component

src/app/app.routes.ts

@@ -16,5 +16,6 @@ export const routes: Routes = [
   { path: RouterConstants.PENDULUM.PATH, loadComponent: () => import('./pages/algorithms/pendulum/pendulum.component').then(m => m.default) },
   { path: RouterConstants.CLOTH.PATH, loadComponent: () => import('./pages/algorithms/cloth/cloth.component').then(m => m.ClothComponent) },
   { path: RouterConstants.FOUR_COLOR.PATH, loadComponent: () => import('./pages/algorithms/four-color/four-color.component').then(m => m.FourColorComponent) },
+  { path: RouterConstants.STOPWATCH.PATH, loadComponent: () => import('./pages/stopwatch/stopwatch.component').then(m => m.StopwatchComponent) },
 ];
 

src/app/constants/RouterConstants.ts

@@ -64,5 +64,10 @@
     PATH: 'imprint',
     LINK: '/imprint',
   };
+
+  static readonly STOPWATCH = {
+    PATH: 'stopwatch',
+    LINK: '/stopwatch',
+  };
 }
 

src/app/layout/topbar/topbar.component.html

@@ -12,6 +12,8 @@
        [routerLink]="RouterConstants.PROJECTS.LINK" routerLinkActive="active" mat-button>{{ 'TOPBAR.PROJECTS' | translate }}</a>
     <a class="opacity-70 transition-opacity duration-150 hover:opacity-100 relative after:content-[''] after:absolute after:bottom-1 after:left-2.5 after:right-2.5 after:h-0.5 after:bg-current after:rounded-sm after:scale-x-0 after:transition-transform [&.active]:opacity-100 [&.active]:after:scale-x-100"
        [routerLink]="RouterConstants.ALGORITHMS.LINK" routerLinkActive="active" mat-button>{{ 'TOPBAR.ALGORITHMS' | translate }}</a>
+    <a class="opacity-70 transition-opacity duration-150 hover:opacity-100 relative after:content-[''] after:absolute after:bottom-1 after:left-2.5 after:right-2.5 after:h-0.5 after:bg-current after:rounded-sm after:scale-x-0 after:transition-transform [&.active]:opacity-100 [&.active]:after:scale-x-100"
+       [routerLink]="RouterConstants.STOPWATCH.LINK" routerLinkActive="active" mat-button>{{ 'TOPBAR.STOPWATCH' | translate }}</a>
     <a class="opacity-70 transition-opacity duration-150 hover:opacity-100 relative after:content-[''] after:absolute after:bottom-1 after:left-2.5 after:right-2.5 after:h-0.5 after:bg-current after:rounded-sm after:scale-x-0 after:transition-transform [&.active]:opacity-100 [&.active]:after:scale-x-100"
        [routerLink]="RouterConstants.IMPRINT.LINK" routerLinkActive="active" mat-button>{{ 'TOPBAR.IMPRINT' | translate }}</a>
   </nav>
@@ -34,6 +36,9 @@
     <button mat-menu-item [routerLink]="RouterConstants.ALGORITHMS.LINK">
       {{ 'TOPBAR.ALGORITHMS' | translate }}
     </button>
+    <button mat-menu-item [routerLink]="RouterConstants.STOPWATCH.LINK">
+      {{ 'TOPBAR.STOPWATCH' | translate }}
+    </button>
     <button mat-menu-item [routerLink]="RouterConstants.IMPRINT.LINK">
       {{ 'TOPBAR.IMPRINT' | translate }}
     </button>

src/app/pages/stopwatch/stopwatch.component.html

@@ -0,0 +1,75 @@
+<mat-card class="w-full max-w-[1920px] p-5">
+  <mat-card-header>
+    <mat-card-title>{{ 'STOPWATCH.TITLE' | translate }}</mat-card-title>
+  </mat-card-header>
+  <mat-card-content>
+    <div class="flex flex-col items-center gap-6 mt-4">
+      <div
+        class="font-mono tabular-nums tracking-wider text-[clamp(2.5rem,8vw,5rem)] font-semibold leading-none rounded-2xl px-6 py-3 ring-2 ring-transparent transition-all duration-300 ease-out"
+        [class]="flashing()
+          ? 'scale-110 !text-[var(--mat-sys-primary)] !ring-[var(--mat-sys-primary)] shadow-[0_0_40px_var(--mat-sys-primary)]'
+          : ''"
+      >
+        {{ display() }}
+      </div>
+
+      <div class="flex flex-wrap gap-3 justify-center">
+        <button mat-flat-button color="primary" (click)="start()" [disabled]="state() === 'running'">
+          <mat-icon>play_arrow</mat-icon>
+          {{ 'STOPWATCH.START' | translate }}
+        </button>
+        <button mat-flat-button color="accent" (click)="pause()" [disabled]="state() !== 'running'">
+          <mat-icon>pause</mat-icon>
+          {{ 'STOPWATCH.PAUSE' | translate }}
+        </button>
+        <button mat-stroked-button (click)="stop()" [disabled]="state() === 'idle' && elapsedMs() === 0">
+          <mat-icon>stop</mat-icon>
+          {{ 'STOPWATCH.STOP' | translate }}
+        </button>
+        <button mat-stroked-button (click)="reset()" [disabled]="elapsedMs() === 0 && state() === 'idle'">
+          <mat-icon>restart_alt</mat-icon>
+          {{ 'STOPWATCH.RESET' | translate }}
+        </button>
+      </div>
+
+      <div class="flex flex-col gap-3 items-center w-full max-w-[520px]">
+        <mat-checkbox [checked]="intervalEnabled()" (change)="intervalEnabled.set($event.checked)">
+          {{ 'STOPWATCH.INTERVAL_ENABLED' | translate }}
+        </mat-checkbox>
+
+        <div class="flex flex-wrap gap-3 items-center justify-center">
+          <mat-form-field appearance="outline" class="w-[160px]">
+            <mat-label>{{ 'STOPWATCH.INTERVAL_MINUTES' | translate }}</mat-label>
+            <input
+              matInput
+              type="number"
+              min="0"
+              step="1"
+              [disabled]="!intervalEnabled()"
+              [ngModel]="intervalMinutes()"
+              (ngModelChange)="intervalMinutes.set($event)"
+            />
+          </mat-form-field>
+
+          <mat-form-field appearance="outline" class="w-[160px]">
+            <mat-label>{{ 'STOPWATCH.INTERVAL_SECONDS' | translate }}</mat-label>
+            <input
+              matInput
+              type="number"
+              min="0"
+              max="59"
+              step="1"
+              [disabled]="!intervalEnabled()"
+              [ngModel]="intervalSeconds()"
+              (ngModelChange)="intervalSeconds.set($event)"
+            />
+          </mat-form-field>
+        </div>
+
+        <p class="m-0 opacity-70 text-sm text-center">
+          {{ 'STOPWATCH.INTERVAL_HINT' | translate }}
+        </p>
+      </div>
+    </div>
+  </mat-card-content>
+</mat-card>

src/app/pages/stopwatch/stopwatch.component.ts

@@ -0,0 +1,186 @@
+import {Component, computed, OnDestroy, signal} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {MatButtonModule} from '@angular/material/button';
+import {MatCardModule} from '@angular/material/card';
+import {MatFormFieldModule} from '@angular/material/form-field';
+import {MatIconModule} from '@angular/material/icon';
+import {MatInputModule} from '@angular/material/input';
+import {MatCheckboxModule} from '@angular/material/checkbox';
+import {TranslateModule} from '@ngx-translate/core';
+
+type StopwatchState = 'idle' | 'running' | 'paused';
+
+@Component({
+  selector: 'app-stopwatch',
+  standalone: true,
+  imports: [
+    FormsModule,
+    MatButtonModule,
+    MatCardModule,
+    MatFormFieldModule,
+    MatIconModule,
+    MatInputModule,
+    MatCheckboxModule,
+    TranslateModule
+  ],
+  templateUrl: './stopwatch.component.html'
+})
+export class StopwatchComponent implements OnDestroy {
+  readonly state = signal<StopwatchState>('idle');
+  readonly elapsedMs = signal(0);
+
+  readonly intervalEnabled = signal(false);
+  readonly intervalMinutes = signal(2);
+  readonly intervalSeconds = signal(0);
+
+  readonly flashing = signal(false);
+
+  readonly display = computed(() => formatElapsed(this.elapsedMs()));
+
+  private rafId: number | null = null;
+  private startTimestamp = 0;
+  private accumulatedMs = 0;
+  private previousElapsedMs = 0;
+  private audioContext: AudioContext | null = null;
+  private flashTimeoutId: number | null = null;
+
+  start(): void {
+    if (this.state() === 'running') {
+      return;
+    }
+    this.ensureAudioContext();
+    this.startTimestamp = performance.now();
+    this.previousElapsedMs = this.accumulatedMs;
+    this.state.set('running');
+    this.tick();
+  }
+
+  pause(): void {
+    if (this.state() !== 'running') {
+      return;
+    }
+    this.accumulatedMs = this.elapsedMs();
+    this.cancelTick();
+    this.state.set('paused');
+  }
+
+  stop(): void {
+    this.cancelTick();
+    this.accumulatedMs = 0;
+    this.previousElapsedMs = 0;
+    this.elapsedMs.set(0);
+    this.state.set('idle');
+  }
+
+  reset(): void {
+    this.stop();
+  }
+
+  ngOnDestroy(): void {
+    this.cancelTick();
+    if (this.flashTimeoutId !== null) {
+      clearTimeout(this.flashTimeoutId);
+      this.flashTimeoutId = null;
+    }
+    if (this.audioContext) {
+      this.audioContext.close().catch(() => undefined);
+      this.audioContext = null;
+    }
+  }
+
+  private tick = (): void => {
+    if (this.state() !== 'running') {
+      return;
+    }
+    const now = performance.now();
+    const newElapsed = this.accumulatedMs + (now - this.startTimestamp);
+
+    this.checkIntervalCrossing(this.previousElapsedMs, newElapsed);
+    this.previousElapsedMs = newElapsed;
+    this.elapsedMs.set(newElapsed);
+
+    this.rafId = requestAnimationFrame(this.tick);
+  };
+
+  private cancelTick(): void {
+    if (this.rafId !== null) {
+      cancelAnimationFrame(this.rafId);
+      this.rafId = null;
+    }
+  }
+
+  private checkIntervalCrossing(prevMs: number, currMs: number): void {
+    if (!this.intervalEnabled()) {
+      return;
+    }
+    const intervalMs = this.intervalMinutes() * 60_000 + this.intervalSeconds() * 1_000;
+    if (intervalMs <= 0) {
+      return;
+    }
+    const prevTick = Math.floor(prevMs / intervalMs);
+    const currTick = Math.floor(currMs / intervalMs);
+    if (currTick > prevTick) {
+      this.beep();
+      this.triggerFlash();
+    }
+  }
+
+  private triggerFlash(): void {
+    if (this.flashTimeoutId !== null) {
+      clearTimeout(this.flashTimeoutId);
+    }
+    this.flashing.set(true);
+    this.flashTimeoutId = window.setTimeout(() => {
+      this.flashing.set(false);
+      this.flashTimeoutId = null;
+    }, 450);
+  }
+
+  private ensureAudioContext(): void {
+    if (this.audioContext) {
+      return;
+    }
+    const Ctor = window.AudioContext ?? (window as unknown as { webkitAudioContext?: typeof AudioContext }).webkitAudioContext;
+    if (Ctor) {
+      this.audioContext = new Ctor();
+    }
+  }
+
+  private beep(): void {
+    if (!this.audioContext) {
+      return;
+    }
+    const ctx = this.audioContext;
+    const oscillator = ctx.createOscillator();
+    const gain = ctx.createGain();
+
+    oscillator.type = 'sine';
+    oscillator.frequency.value = 880;
+
+    const now = ctx.currentTime;
+    const duration = 0.18;
+    gain.gain.setValueAtTime(0, now);
+    gain.gain.linearRampToValueAtTime(0.25, now + 0.01);
+    gain.gain.linearRampToValueAtTime(0, now + duration);
+
+    oscillator.connect(gain);
+    gain.connect(ctx.destination);
+    oscillator.start(now);
+    oscillator.stop(now + duration);
+  }
+}
+
+function formatElapsed(totalMs: number): string {
+  const ms = Math.floor(totalMs % 1000);
+  const totalSeconds = Math.floor(totalMs / 1000);
+  const seconds = totalSeconds % 60;
+  const totalMinutes = Math.floor(totalSeconds / 60);
+  const minutes = totalMinutes % 60;
+  const hours = Math.floor(totalMinutes / 60);
+
+  return `${pad(hours, 2)}:${pad(minutes, 2)}:${pad(seconds, 2)}.${pad(ms, 3)}`;
+}
+
+function pad(value: number, length: number): string {
+  return value.toString().padStart(length, '0');
+}

src/assets/i18n/de.json

@@ -8,6 +8,7 @@
     "IMPRINT": "Impressum",
     "PROJECTS": "Projekte",
     "ALGORITHMS": "Algorithmen",
+    "STOPWATCH": "Stoppuhr",
     "SETTINGS": "Einstellungen",
     "LANGUAGE": "Sprache",
     "APPEARANCE": "Darstellung"
@@ -588,5 +589,16 @@
     "ALERT": {
       "NO_SOLUTION": "Keine Lösung gefunden (das sollte bei einer planaren Karte nicht passieren!)."
     }
+  },
+  "STOPWATCH": {
+    "TITLE": "Stoppuhr",
+    "START": "Start",
+    "PAUSE": "Pause",
+    "STOP": "Stopp",
+    "RESET": "Zurücksetzen",
+    "INTERVAL_ENABLED": "Signalton bei Intervall",
+    "INTERVAL_MINUTES": "Minuten",
+    "INTERVAL_SECONDS": "Sekunden",
+    "INTERVAL_HINT": "Spielt einen kurzen Ton ab, sobald die verstrichene Zeit ein Vielfaches des Intervalls überschreitet."
   }
 }

src/assets/i18n/en.json

@@ -8,6 +8,7 @@
     "IMPRINT": "Impressum",
     "PROJECTS": "Projects",
     "ALGORITHMS": "Algorithms",
+    "STOPWATCH": "Stopwatch",
     "SETTINGS": "Settings",
     "LANGUAGE": "Language",
     "APPEARANCE": "Appearance"
@@ -587,5 +588,16 @@
     "ALERT": {
       "NO_SOLUTION": "No solution found (this should not happen for a planar map!)."
     }
+  },
+  "STOPWATCH": {
+    "TITLE": "Stopwatch",
+    "START": "Start",
+    "PAUSE": "Pause",
+    "STOP": "Stop",
+    "RESET": "Reset",
+    "INTERVAL_ENABLED": "Beep at interval",
+    "INTERVAL_MINUTES": "Minutes",
+    "INTERVAL_SECONDS": "Seconds",
+    "INTERVAL_HINT": "Plays a short tone whenever the elapsed time crosses a multiple of the interval."
   }
 }