Attachment previews

let tokens = cx.theme().semantic_tokens();
let composer_items = demo_attachments(&self.demo_thumbnail)
    .into_iter()
    .filter(|item| !self.removed_attachments.contains(item.id()))
    .collect::<Vec<_>>();
let status: SharedString = self
    .last_attachment_event
    .clone()
    .unwrap_or_else(|| "Remove a composer file or open a message file".into());
let caption = |text: &'static str| {
    div()
        .text_xs()
        .text_color(cx.theme().muted_foreground)
        .child(text)
};
v_flex()
    .gap(tokens.spacing.md)
    .child(caption("Composer: compact and removable"))
    .child(
        AttachmentStrip::new("composer-attachments")
            .label("Prompt attachments")
            .items(composer_items)
            .removable(true)
            .compact(true)
            .on_event(cx.listener(|this, event: &AttachmentEvent, _, cx| {
                if let AttachmentEvent::Removed { id } = event {
                    this.removed_attachments.insert(id.clone());
                    this.last_attachment_event =
                        Some(format!("Removed {id}").into());
                    cx.notify();
                }
            })),
    )
    .child(caption("Message: read-only, openable tiles"))
    .child(
        AttachmentStrip::new("message-attachments")
            .label("Message attachments")
            .items(demo_attachments(&self.demo_thumbnail))
            .on_event(cx.listener(|this, event: &AttachmentEvent, _, cx| {
                if let AttachmentEvent::Opened { id } = event {
                    this.last_attachment_event =
                        Some(format!("Opened {id}").into());
                    cx.notify();
                }
            })),
    )
    .child(caption("Upload lifecycle: queued, uploading, failed"))
    .child(
        AttachmentStrip::new("attachment-states")
            .label("Upload states")
            .items(demo_attachment_states()),
    )
    .child(
        div()
            .id("attachments-story-status")
            .role(Role::Status)
            .aria_label(status.clone())
            .text_xs()
            .text_color(cx.theme().muted_foreground)
            .child(status),
    )