frus-widgets 0.4.0

//! [`DateTimePicker`]: a **date-and-time flow** in a single widget — the
//! [`crate::DatePicker`] calendar above the [`crate::TimePicker`] time picker, topped by
//! a **summary** of the selection.
//!
//! Purely composite and controlled: it only combines the two sub-pickers and relays
//! their messages; the state, date and time, lives in the application.

use frus_core::{Rect, Scene};
use frus_layout::{Dimension, FlexDirection, Style};

use crate::datepicker::DatePicker;
use crate::interaction::Status;
use crate::text::Text;
use crate::theme::Theme;
use crate::timepicker::TimePicker;
use crate::widget::Widget;

/// A date-and-time picker.
pub struct DateTimePicker<Msg = crate::callback::Callback> {
    children: Vec<Box<dyn Widget<Msg>>>,
}

impl<Msg: Clone + 'static> DateTimePicker<Msg> {
    /// Creates a date-and-time flow. The **date** part shows `year`/`month` (1–12)
    /// with `day` selected if there is one — `on_day(day)` on click, `on_nav(±1)` to
    /// change month — while the **time** part shows `hour`/`minute`
    /// (`on_hour`/`on_minute`). A "Month day, year  HH:MM" summary tops it all once a
    /// day is chosen.
    #[allow(clippy::too_many_arguments)]
    pub fn new(
        year: i32,
        month: u32,
        day: Option<u32>,
        hour: u32,
        minute: u32,
        on_day: impl Fn(u32) -> Msg + 'static,
        on_nav: impl Fn(i32) -> Msg + 'static,
        on_hour: impl Fn(u32) -> Msg + 'static,
        on_minute: impl Fn(u32) -> Msg + 'static,
    ) -> Self {
        let month = month.clamp(1, 12);
        let (hour, minute) = (hour.min(23), minute.min(59));

        let date = DatePicker::new(year, month, day, on_day, on_nav);
        let time = TimePicker::new(hour, minute, on_hour, on_minute);

        let mut children: Vec<Box<dyn Widget<Msg>>> = Vec::new();
        if let Some(day) = day {
            let summary = format!(
                "{} {day}, {year}  {hour:02}:{minute:02}",
                crate::localizations::of().months()[(month - 1) as usize]
            );
            children.push(Box::new(Text::new(summary).size(16.0)));
        }
        children.push(Box::new(date));
        children.push(Box::new(time));

        Self { children }
    }
}

impl<Msg: Clone> Widget<Msg> for DateTimePicker<Msg> {
    fn style(&self) -> Style {
        Style {
            width: Dimension::Auto,
            flex_direction: FlexDirection::Column,
            gap: 16.0,
            ..Default::default()
        }
    }

    fn children(&self) -> &[Box<dyn Widget<Msg>>] {
        &self.children
    }

    fn paint(&self, _bounds: Rect, _status: Status, _theme: &Theme, _scene: &mut Scene) {}

    fn on_click(&self) -> Option<Msg> {
        None
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::{build_ui, Runtime, Size};
    use frus_core::Primitive;

    #[derive(Clone, Debug, PartialEq)]
    enum Msg {
        Day(u32),
        Nav(i32),
        Hour(u32),
        Minute(u32),
    }

    #[test]
    fn summary_appears_only_when_a_day_is_picked() {
        // With no day: [date, time]. With one: [summary, date, time].
        let without = DateTimePicker::new(
            2026,
            7,
            None,
            9,
            30,
            Msg::Day,
            Msg::Nav,
            Msg::Hour,
            Msg::Minute,
        );
        assert_eq!(Widget::<Msg>::children(&without).len(), 2);

        let with = DateTimePicker::new(
            2026,
            7,
            Some(11),
            9,
            30,
            Msg::Day,
            Msg::Nav,
            Msg::Hour,
            Msg::Minute,
        );
        assert_eq!(Widget::<Msg>::children(&with).len(), 3);
    }

    #[test]
    fn renders_the_combined_summary() {
        let dt = DateTimePicker::new(
            2026,
            7,
            Some(11),
            9,
            30,
            Msg::Day,
            Msg::Nav,
            Msg::Hour,
            Msg::Minute,
        );
        let ui = build_ui(
            &dt,
            Size::new(280.0, 520.0),
            &Runtime::default(),
            &Theme::default(),
        );
        let has_summary =
            ui.scene().primitives().iter().any(
                |p| matches!(p, Primitive::Text { text, .. } if text == "July 11, 2026  09:30"),
            );
        assert!(has_summary, "the date-and-time summary is shown");
    }
}