// file-size.pipe.ts
import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: 'fileSize', standalone: true })
export class FileSizePipe implements PipeTransform {
  transform(bytes: number): string {
    if (bytes < 1024) return `${bytes} B`;

    const units = ['KB', 'MB', 'GB', 'TB'];
    let size = bytes / 1024;
    let unitIndex = 0;

    while (size >= 1024 && unitIndex < units.length - 1) {
      size /= 1024;
      unitIndex++;
    }

    // Drop a trailing ".0" so 2 MB shows as "2 MB", not "2.0 MB".
    const rounded = Math.round(size * 10) / 10;
    return `${rounded} ${units[unitIndex]}`;
  }
}

// downloads.component.ts
import { Component } from '@angular/core';
import { FileSizePipe } from './file-size.pipe';

@Component({
  selector: 'app-downloads',
  standalone: true,
  imports: [FileSizePipe],
  template: `
    <p>{{ 512 | fileSize }}</p>       <!-- 512 B -->
    <p>{{ 1536 | fileSize }}</p>      <!-- 1.5 KB -->
    <p>{{ 2097152 | fileSize }}</p>   <!-- 2 MB -->
  `,
})
export class DownloadsComponent {}

/*
  Notes:
  - The while loop steps up through the units (KB, MB, GB, TB),
    dividing by 1024 each time until the size is below 1024 or the
    largest unit is reached.
  - Rounding to one decimal and stripping a trailing .0 via Math.round
    keeps "2 MB" clean while still allowing "1.5 KB".
*/