Calendar · Agenda and people: an agenda, an event's details, its guests

AgendaView lists the days ahead under their names, whole days first,
then by the hour, and leaves out days with nothing; it rides on
lists::Sections, so a press or an arrow selects and Enter opens. An
empty stretch says nothing is planned.

EventPopover is an event's chip that opens its details: its title in
its hue, when and where, who is asked, and Edit and Delete when the
owner handles them. It opens through Popover::with_opener, which now
hands any element the toggle and keeps focus, placement and every way
out in the popover. AttendeeList counts the answers and lists each
guest with their answer, the organizer first. A hue worn in a row is
now data_display::color_mark, for mail labels and events alike.

src/calendar/popover.rs

@@ -0,0 +1,185 @@
+use std::rc::Rc;
+
+use gpui::{
+    AnyElement, App, ElementId, FontWeight, InteractiveElement, IntoElement, ParentElement,
+    RenderOnce, SharedString, Styled, Window, div, prelude::*,
+};
+use jiff::tz::TimeZone;
+
+use super::{
+    chip::{EventChip, tint},
+    event::{Event, When, hours},
+    people::{Attendee, AttendeeList},
+};
+use crate::{
+    buttons::{Button, ButtonVariant},
+    data_display::color_mark,
+    forms::OnValue,
+    overlays::Popover,
+    primitives::{Icon, IconName},
+    theme::{ActiveTheme, ControlSize, IconSize, TextSize},
+    typography::format,
+};
+
+/// When an event happens, in full: the day's name and its hours, or its span of whole days.
+pub(crate) fn when(event: &Event, zone: &TimeZone) -> String {
+    let (first, _) = event.days(zone);
+    match event.when {
+        When::AllDay { .. } if event.spans(zone) => hours(event, zone),
+        _ => format!("{} · {}", first.strftime("%A, %B %-d"), hours(event, zone)),
+    }
+}
+
+/// An event's chip that opens its details: its title in its hue, when and where, who comes, and what can be done with it. A press outside or Escape closes them.
+#[derive(IntoElement)]
+pub struct EventPopover {
+    id: ElementId,
+    event: Event,
+    zone: Option<TimeZone>,
+    attendees: Vec<Attendee>,
+    on_edit: Option<OnValue>,
+    on_delete: Option<OnValue>,
+}
+
+impl EventPopover {
+    pub fn new(id: impl Into<ElementId>, event: Event) -> Self {
+        Self {
+            id: id.into(),
+            event,
+            zone: None,
+            attendees: Vec::new(),
+            on_edit: None,
+            on_delete: None,
+        }
+    }
+
+    /// The zone its hours read in; the system's otherwise.
+    pub fn zone(mut self, zone: TimeZone) -> Self {
+        self.zone = Some(zone);
+        self
+    }
+
+    /// Who is asked, shown under where.
+    pub fn attendees(mut self, attendees: impl IntoIterator<Item = Attendee>) -> Self {
+        self.attendees = attendees.into_iter().collect();
+        self
+    }
+
+    /// Offers Edit; gets the event's key.
+    pub fn on_edit(
+        mut self,
+        handler: impl Fn(&SharedString, &mut Window, &mut App) + 'static,
+    ) -> Self {
+        self.on_edit = Some(Rc::new(handler));
+        self
+    }
+
+    /// Offers Delete; gets the event's key.
+    pub fn on_delete(
+        mut self,
+        handler: impl Fn(&SharedString, &mut Window, &mut App) + 'static,
+    ) -> Self {
+        self.on_delete = Some(Rc::new(handler));
+        self
+    }
+}
+
+/// A line of the details: an icon, then its words, wrapping.
+fn line(icon: IconName, words: String, cx: &App) -> AnyElement {
+    let theme = cx.theme();
+    div()
+        .flex()
+        .items_start()
+        .gap_2()
+        .child(
+            Icon::new(icon)
+                .size(IconSize::Sm)
+                .color(theme.colors.fg_subtle),
+        )
+        .child(div().flex_1().min_w_0().child(words))
+        .into_any_element()
+}
+
+impl RenderOnce for EventPopover {
+    fn render(self, _: &mut Window, _: &mut App) -> impl IntoElement {
+        let zone = self
+            .zone
+            .unwrap_or_else(|| format::system_zone("event popover"));
+        let (event, chip_zone) = (self.event.clone(), zone.clone());
+        let (id, chip_id) = (self.id.clone(), (self.id.clone(), "chip"));
+        let details = move |_: &mut Window, cx: &mut App| {
+            let theme = cx.theme();
+            let key = self.event.key.clone();
+            let action = |label: &'static str, variant, handler: Option<OnValue>| {
+                handler.map(|handler| {
+                    let key = key.clone();
+                    Button::new((self.id.clone(), label), label)
+                        .variant(variant)
+                        .size(ControlSize::Sm)
+                        .on_click(move |_, window, cx| {
+                            log::info!("event popover: {label} {key}");
+                            handler(&key, window, cx)
+                        })
+                })
+            };
+            let delete = action("Delete", ButtonVariant::Ghost, self.on_delete.clone());
+            let edit = action("Edit", ButtonVariant::Secondary, self.on_edit.clone());
+            let key = self.event.key.clone();
+            div()
+                .debug_selector(move || format!("event-popover {key}"))
+                .w(theme.calendar().card)
+                .flex()
+                .flex_col()
+                .gap_3()
+                .text_size(theme.text_size(TextSize::Sm))
+                .text_color(theme.colors.fg)
+                .child(
+                    div()
+                        .flex()
+                        .items_start()
+                        .gap_2()
+                        .child(color_mark(tint(&self.event, cx), cx))
+                        .child(
+                            div()
+                                .flex_1()
+                                .min_w_0()
+                                .text_size(theme.text_size(TextSize::Base))
+                                .font_weight(FontWeight::SEMIBOLD)
+                                .child(self.event.title.clone()),
+                        ),
+                )
+                .child(line(IconName::Clock, when(&self.event, &zone), cx))
+                .children(
+                    self.event
+                        .place
+                        .clone()
+                        .map(|place| line(IconName::MapPin, place.to_string(), cx)),
+                )
+                .when(!self.attendees.is_empty(), |details| {
+                    details.child(AttendeeList::new(
+                        (self.id.clone(), "guests"),
+                        self.attendees.clone(),
+                    ))
+                })
+                .when(delete.is_some() || edit.is_some(), |details| {
+                    details.child(
+                        div()
+                            .flex()
+                            .justify_end()
+                            .gap_2()
+                            .children(delete)
+                            .children(edit),
+                    )
+                })
+        };
+        Popover::with_opener(
+            id,
+            move |toggle| {
+                EventChip::new(chip_id, event)
+                    .zone(chip_zone)
+                    .on_click(move |window, cx| toggle(window, cx))
+            },
+            details,
+        )
+    }
+}