platform/packages/ui/src/components/ScrollBox.svelte

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<script lang="ts">
  import { afterUpdate } from 'svelte'

  export let vertical: boolean = false
  export let stretch: boolean = false
  export let bothScroll: boolean = false
  export let noShift: boolean = false
  export let autoscrollable: boolean = false

  let div: HTMLElement
  let autoscroll: boolean = true

  afterUpdate(async () => {
    if (autoscrollable && autoscroll) div.scrollTo(0, div.scrollHeight)
  })

  function setAutoscroll () {
    autoscroll = div.scrollTop > div.scrollHeight - div.clientHeight - 50
  }
</script>

<div class="scroll" bind:this={div} class:vertical class:bothScroll class:noShift on:scroll={setAutoscroll}>
  <div class="box" class:stretch>
    <slot />
  </div>
</div>

<style lang="scss">
  .scroll {
    position: relative;
    width: auto;
    height: 100%;
    overflow-x: auto;
    overflow-y: hidden;
    margin-right: 0;
    margin-bottom: -0.75rem;

    .box {
      position: absolute;
      display: flex;
      padding: 0 0 0.375rem 0;
      top: 0;
      left: 0;
      width: auto;
      height: 100%;
      &.stretch {
        width: 100%;
      }
    }

    &.vertical {
      margin: 0 -0.5rem 0 -0.5rem;
      overflow-x: hidden;
      overflow-y: auto;
      .box {
        flex-direction: column;
        padding: 0 0.5rem 0 0.5rem;
        width: 100%;
        height: auto;
        &.stretch {
          height: 100%;
        }
      }
    }

    &.bothScroll {
      margin: 0 -0.375rem -0.375rem 0;
      overflow: auto;
      .box {
        padding: 0 0.375rem 0.375rem 0;
      }
    }

    &.noShift {
      margin: 0;
      .box {
        padding: 0;
      }
    }
  }
</style>