guise-ui 1.5.3

//! `NumberInput` — a numeric text field with stepper buttons (gpui entity).
//!
//! Owns an editable buffer (reusing [`TextEdit`]) constrained to numeric input,
//! plus optional min/max/step. Emits [`NumberInputEvent`] with the parsed value
//! whenever it changes.

use gpui::prelude::*;
use gpui::{
  div, px, App, Context, Entity, EventEmitter, FocusHandle, IntoElement, KeyDownEvent,
  SharedString, Window,
};

use super::line::{self, Line, LineEditor, LineState};
use super::{control_metrics, Field, KeyOutcome, TextEdit};
use crate::devtools::ProbedAny;
use crate::icon::{Icon, IconName};
use crate::reactive::Signal;
use crate::theme::{theme, Size};

/// Emitted when the numeric value changes. Carries the parsed value.
#[derive(Debug, Clone, Copy)]
pub struct NumberInputEvent(pub f64);

/// A numeric input. Create with `cx.new(|cx| NumberInput::new(cx))`.
pub struct NumberInput {
  edit: TextEdit,
  state: LineState,
  focus: FocusHandle,
  min: Option<f64>,
  max: Option<f64>,
  step: f64,
  label: Option<SharedString>,
  description: Option<SharedString>,
  error: Option<SharedString>,
  size: Size,
  disabled: bool,
}

impl EventEmitter<NumberInputEvent> for NumberInput {}

/// Parse a numeric buffer, tolerating surrounding whitespace and a lone `-`.
fn parse_number(s: &str) -> Option<f64> {
  let t = s.trim();
  if t.is_empty() || t == "-" {
    return None;
  }
  t.parse::<f64>().ok()
}

fn clamp(v: f64, min: Option<f64>, max: Option<f64>) -> f64 {
  let v = min.map_or(v, |m| v.max(m));
  max.map_or(v, |m| v.min(m))
}

/// Format without a trailing `.0` for whole numbers.
fn format_number(v: f64) -> String {
  if v.fract() == 0.0 {
    format!("{}", v as i64)
  } else {
    format!("{v}")
  }
}

impl NumberInput {
  pub fn new(cx: &mut Context<Self>) -> Self {
    NumberInput {
      edit: TextEdit::new(""),
      state: LineState::new(),
      focus: cx.focus_handle().tab_stop(true),
      min: None,
      max: None,
      step: 1.0,
      label: None,
      description: None,
      error: None,
      size: Size::Sm,
      disabled: false,
    }
  }

  pub fn value(mut self, value: f64) -> Self {
    let value = clamp(value, self.min, self.max);
    self.edit = TextEdit::new(&format_number(value));
    self
  }

  pub fn min(mut self, min: f64) -> Self {
    self.min = Some(min);
    self
  }

  pub fn max(mut self, max: f64) -> Self {
    self.max = Some(max);
    self
  }

  pub fn step(mut self, step: f64) -> Self {
    self.step = step;
    self
  }

  pub fn label(mut self, label: impl Into<SharedString>) -> Self {
    self.label = Some(label.into());
    self
  }

  pub fn description(mut self, description: impl Into<SharedString>) -> Self {
    self.description = Some(description.into());
    self
  }

  pub fn error(mut self, error: impl Into<SharedString>) -> Self {
    self.error = Some(error.into());
    self
  }

  pub fn size(mut self, size: Size) -> Self {
    self.size = size;
    self
  }

  pub fn disabled(mut self, disabled: bool) -> Self {
    self.disabled = disabled;
    self
  }

  /// The current parsed value, or `None` if the buffer isn't a number.
  pub fn value_f64(&self) -> Option<f64> {
    parse_number(&self.edit.text())
  }

  /// Two-way bind this input's value to a `Signal<f64>`. The signal is the
  /// source of truth: the input adopts its value now (clamped to min/max),
  /// edits write back through [`Signal::set_if_changed`], and signal writes
  /// replace the buffer without emitting [`NumberInputEvent`]. Equality
  /// guards on both directions prevent update loops.
  pub fn bind(entity: &Entity<NumberInput>, signal: &Signal<f64>, cx: &mut App) {
    let initial = signal.get(cx);
    entity.update(cx, |this, cx| this.sync_value(initial, cx));
    let sink = signal.clone();
    cx.subscribe(entity, move |_input, event: &NumberInputEvent, cx| {
      sink.set_if_changed(cx, event.0);
    })
    .detach();
    let input = entity.downgrade();
    cx.observe(signal.entity(), move |observed, cx| {
      let value = *observed.read(cx);
      input.update(cx, |this, cx| this.sync_value(value, cx)).ok();
    })
    .detach();
  }

  /// Set the value programmatically, clamped to min/max. Does not emit —
  /// a host that changed the value already knows.
  pub fn set_value(&mut self, value: f64, cx: &mut Context<Self>) {
    self.sync_value(value, cx);
  }

  /// Raise or lower the ceiling after construction. A value above the new
  /// maximum is pulled down to it, so the field can never show one the
  /// bounds forbid.
  pub fn set_max(&mut self, max: f64, cx: &mut Context<Self>) {
    self.max = Some(max);
    if let Some(current) = self.value_f64() {
      if current > max {
        self.sync_value(max, cx);
        return;
      }
    }
    cx.notify();
  }

  /// Raise or lower the floor after construction, pulling a value below it
  /// up to match.
  pub fn set_min(&mut self, min: f64, cx: &mut Context<Self>) {
    self.min = Some(min);
    if let Some(current) = self.value_f64() {
      if current < min {
        self.sync_value(min, cx);
        return;
      }
    }
    cx.notify();
  }

  /// Programmatic set: clamp and repaint without emitting an event.
  fn sync_value(&mut self, raw: f64, cx: &mut Context<Self>) {
    let next = clamp(raw, self.min, self.max);
    if self.value_f64() != Some(next) {
      self.edit.set_text(&format_number(next));
      cx.notify();
    }
  }

  fn nudge(&mut self, dir: f64, cx: &mut Context<Self>) {
    if self.disabled {
      return;
    }
    let current = parse_number(&self.edit.text()).unwrap_or(0.0);
    let next = clamp(current + dir * self.step, self.min, self.max);
    self.edit.set_text(&format_number(next));
    cx.emit(NumberInputEvent(next));
    cx.notify();
  }

  fn on_key(&mut self, event: &KeyDownEvent, window: &mut Window, cx: &mut Context<Self>) {
    if self.disabled {
      return;
    }
    // The arrows step the value rather than moving a caret up and down a
    // line that doesn't exist, the way a spinner does.
    let ks = &event.keystroke;
    if !ks.modifiers.platform && !ks.modifiers.control && !ks.modifiers.shift {
      match ks.key.as_str() {
        "up" => {
          self.nudge(1.0, cx);
          cx.stop_propagation();
          return;
        }
        "down" => {
          self.nudge(-1.0, cx);
          cx.stop_propagation();
          return;
        }
        _ => {}
      }
    }
    match line::keys(self, event, window, cx) {
      KeyOutcome::Edited | KeyOutcome::Submit => {
        self.line_changed(cx);
        cx.stop_propagation();
      }
      KeyOutcome::Cancel | KeyOutcome::Pass => {}
    }
  }
}

impl LineEditor for NumberInput {
  fn edit(&self) -> &TextEdit {
    &self.edit
  }

  fn edit_mut(&mut self) -> &mut TextEdit {
    &mut self.edit
  }

  fn line(&self) -> &LineState {
    &self.state
  }

  fn line_mut(&mut self) -> &mut LineState {
    &mut self.state
  }

  fn line_focus(&self) -> &FocusHandle {
    &self.focus
  }

  fn line_read_only(&self) -> bool {
    self.disabled
  }

  /// Only what can spell a number gets in — by typing, by IME, or by paste.
  fn line_filter(&self, text: String) -> String {
    text
      .chars()
      .filter(|c| c.is_ascii_digit() || *c == '.' || *c == '-' || *c == 'e' || *c == 'E')
      .collect()
  }

  fn line_changed(&mut self, cx: &mut Context<Self>) {
    if let Some(value) = parse_number(&self.edit.text()) {
      cx.emit(NumberInputEvent(value));
    }
    cx.notify();
  }
}

line::line_input_handler!(NumberInput);
line::line_focus_builders!(NumberInput);

impl Render for NumberInput {
  fn render(&mut self, window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
    let t = theme(cx);
    let (height, pad_x, font) = control_metrics(self.size);
    let radius = t.radius(t.default_radius);
    let focused = self.focus.is_focused(window) && !self.disabled;
    let border = if self.error.is_some() {
      t.color(crate::theme::ColorName::Red, 6)
    } else if focused {
      t.primary()
    } else {
      t.border()
    }
    .hsla();
    let text_color = t.text().hsla();
    let dimmed = t.dimmed().hsla();
    let surface = t.surface().hsla();

    let interior = Line::new(cx.entity()).placeholder(SharedString::new_static("0"), dimmed);

    let stepper = |id: &'static str, icon: IconName| {
      div()
        .id(id)
        .flex()
        .items_center()
        .justify_center()
        .w(px(20.0))
        .h(px(height / 2.0 - 1.0))
        .text_color(dimmed)
        .hover(move |s| s.text_color(text_color))
        .child(Icon::new(icon).size(Size::Xs))
    };

    let steppers = div()
      .flex()
      .flex_col()
      .border_l_1()
      .border_color(border)
      .child(
        stepper("guise-number-inc", IconName::ChevronUp)
          .on_click(cx.listener(|this, _ev, _window, cx| this.nudge(1.0, cx))),
      )
      .child(
        stepper("guise-number-dec", IconName::ChevronDown)
          .on_click(cx.listener(|this, _ev, _window, cx| this.nudge(-1.0, cx))),
      );

    let field = line::wire(div().id("guise-numberinput"), &self.focus, cx)
      .on_key_down(cx.listener(Self::on_key))
      .flex()
      .items_center()
      .justify_between()
      .h(px(height))
      .pl(px(pad_x))
      .rounded(px(radius))
      .border_1()
      .border_color(border)
      .bg(surface)
      .text_size(px(font))
      .line_height(px(font * 1.3))
      .child(div().flex_1().min_w(px(0.0)).child(interior))
      .child(steppers);

    let mut chrome = Field::new().child(if self.disabled {
      field.opacity(0.6)
    } else {
      field
    });
    if let Some(label) = self.label.clone() {
      chrome = chrome.label(label);
    }
    if let Some(error) = self.error.clone() {
      chrome = chrome.error(error);
    } else if let Some(description) = self.description.clone() {
      chrome = chrome.description(description);
    }
    chrome.probe_any("NumberInput")
  }
}