import {
  ChangeDetectionStrategy,
  Component,
  computed,
  input,
} from '@angular/core';
import { Home } from '@task-stream/web/tracker/domain';

/** «+30 %» or «−10 %» against the week before (nothing when there was none). */
function change(now: number, before: number): string {
  if (!before) return now ? 'nuevo' : '';
  const pct = Math.round(((now - before) / before) * 100);
  return `${pct >= 0 ? '+' : '−'}${Math.abs(pct)} %`;
}

/** How the week goes: mine (and my streak) and my projects' teams. */
@Component({
  selector: 'ts-week-stats',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'ts-panel',
    role: 'region',
    'aria-labelledby': 'stats-title',
  },
  styleUrl: './home-panel.scss',
  template: `
    <header class="ts-panel__head">
      <h2 id="stats-title">La semana</h2>
      <span class="ts-muted">Tickets terminados, últimos 7 días</span>
    </header>
    <div class="ts-week">
      <div>
        <p class="ts-week__label">Tú</p>
        <p class="ts-week__value">
          {{ me().thisWeek }}
          @if (myChange(); as c) {
            <span class="ts-week__change" [class.is-down]="c.startsWith('−')">{{
              c
            }}</span>
          }
        </p>
        <p class="ts-week__sub">
          @if (me().streak > 1) {
            {{ me().streak }} días seguidos terminando algo
          } @else if (me().streak === 1) {
            Terminaste algo hoy o ayer
          } @else {
            Sin racha: hoy puede empezar una
          }
        </p>
      </div>
      <div>
        <p class="ts-week__label">Tus equipos</p>
        <p class="ts-week__value">
          {{ team().thisWeek }}
          @if (teamChange(); as c) {
            <span class="ts-week__change" [class.is-down]="c.startsWith('−')">{{
              c
            }}</span>
          }
        </p>
        <div
          class="ts-week__bars"
          role="img"
          [attr.aria-label]="'Terminados por día: ' + team().perDay.join(', ')"
        >
          @for (n of team().perDay; track $index) {
            <span
              [style.height.%]="height(n)"
              [class.is-this-week]="$index >= 7"
              [attr.title]="n + ' terminados'"
            ></span>
          }
        </div>
      </div>
    </div>
  `,
  styles: `
    .ts-week {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 1rem;
    }
    .ts-week__label {
      margin: 0;
      color: var(--ts-muted);
      font-size: 0.75rem;
    }
    .ts-week__value {
      display: flex;
      align-items: baseline;
      gap: 0.5rem;
      margin: 0.125rem 0 0.25rem;
      font-size: 1.75rem;
      font-weight: 700;
    }
    .ts-week__change {
      color: var(--ts-c-green, #2e9e6a);
      font-size: 0.8125rem;
      font-weight: 600;
      &.is-down {
        color: var(--ts-muted);
      }
    }
    .ts-week__sub {
      margin: 0;
      color: var(--ts-ink-soft);
      font-size: 0.8125rem;
    }
    .ts-week__bars {
      display: flex;
      align-items: flex-end;
      gap: 2px;
      height: 2.5rem;
      span {
        flex: 1;
        min-height: 2px;
        border-radius: 2px 2px 0 0;
        background: color-mix(in srgb, var(--ts-brand) 35%, transparent);
        &.is-this-week {
          background: var(--ts-brand);
        }
      }
    }
  `,
})
export class WeekStatsComponent {
  readonly me = input.required<Home['me']>();
  readonly team = input.required<Home['team']>();

  protected readonly myChange = computed(() =>
    change(this.me().thisWeek, this.me().lastWeek),
  );
  protected readonly teamChange = computed(() =>
    change(this.team().thisWeek, this.team().lastWeek),
  );
  private readonly max = computed(() => Math.max(1, ...this.team().perDay));

  protected height(n: number): number {
    return (n / this.max()) * 100;
  }
}