rust_widgets 2.7.0

// SPDX-FileCopyrightText: Copyright (c) 2026 Mike Li/Mikewolfli/Wei Li(mikewolfli@163.com)
// SPDX-License-Identifier: MIT

//! Dialog widgets.
use crate::core::{Color, Rect};
use crate::render::RenderContext;

pub mod bottom_sheet;
pub mod color_dialog;
pub mod dialog_widget;
pub mod file_dialog;
pub mod find_replace_dialog;
pub mod font_dialog;
pub mod input_dialog;
pub mod message_box;
pub mod modal_bottom_sheet;
pub mod popover;
pub mod popup_window;
pub mod progress_dialog;
pub mod tooltip;
pub mod wizard;
// Re-export dialog types
pub use bottom_sheet::BottomSheet;
pub use color_dialog::ColorDialog;
pub use dialog_widget::Dialog;
pub use file_dialog::FileDialog;
pub use find_replace_dialog::FindReplaceDialog;
pub use font_dialog::FontDialog;
pub use input_dialog::InputDialog;
pub use message_box::MessageBox;
pub use modal_bottom_sheet::ModalBottomSheet;
pub use popover::Popover;
pub use popup_window::PopupWindow;
pub use progress_dialog::ProgressDialog;
pub use tooltip::Tooltip;
pub use wizard::{WizardDialog, WizardStep};

/// Paints the modal scrim over the control's whole rectangle.
///
/// # Why this is one function and not six copies
///
/// Every modal dialog in this module dims the page it sits on, and six of them were silently
/// missing it: `Dialog` and `MessageBox` were fixed first, then the scan showed
/// `color_dialog` / `file_dialog` / `font_dialog` / `input_dialog` / `progress_dialog` carried a
/// `modal` flag with nothing painted for it. Six copies of the same six lines is how six of them
/// came to diverge in the first place, so the body lives here once.
///
/// # Why the `Scrim` role rather than a blend
///
/// BLUE21 B23 recorded that blending toward the ink **lightens** a dark page — a scrim that
/// brightens what it covers is the defect stated in `Colors::scrim`'s own documentation. The
/// role lets a dark theme dim deliberately while a light theme darkens, and the literal survives
/// only as the fallback for a theme that predates the role.
pub(crate) fn draw_modal_scrim(context: &mut RenderContext, page: Rect) {
    draw_modal_scrim_scaled(context, page, 1.0);
}

/// Paints the modal scrim at `strength` of its resolved opacity, for a backdrop that fades in.
///
/// Scaling the **alpha** rather than blending toward the page is the one form that is right for
/// both a dark scrim (which must get darker as it arrives) and a light one (which must get lighter):
/// a blend toward the window fill would move a scrim in the wrong direction in one of the two
/// appearances. `strength` is clamped, and the whole plane is skipped at zero so a hidden dialog
/// leaves the page untouched.
pub(crate) fn draw_modal_scrim_scaled(context: &mut RenderContext, page: Rect, strength: f32) {
    let strength = strength.clamp(0.0, 1.0);
    if strength <= 0.0 {
        return;
    }
    let scrim = crate::style::layer_color(crate::style::LayerColor::Scrim)
        .unwrap_or_else(|| Color::BLACK.with_alpha(82));
    let scrim = scrim.with_alpha((scrim.a as f32 * strength) as u8);
    context.fill_rect(page, scrim);
}

/// How small a revealing modal is at the instant it appears: 0.92 of its settled size.
///
/// A dialog that grows from nothing reads as a pop rather than an arrival, and one that grows from
/// far away reads as a zoom unrelated to a dialog's purpose. A few percent is the "settle" every
/// platform uses; the value is deliberately *not* zero, so the first visible frame already shows the
/// dialog's shape. Shared by every modal family so a dialog and a message box arrive alike — two
/// nearby literals is exactly how the eight dialogs acquired four title-bar heights (rule #101).
pub(crate) const REVEAL_MIN_SCALE: f32 = 0.92;

/// Scales `rect` about its own centre, rounding outward so a shrinking frame never loses a pixel
/// column to truncation while it is still meant to be visible.
///
/// The frame is grown from its centre rather than from a corner because a dialog that grows from a
/// corner reads as a panel sliding in, which is a different affordance (that is what `bottom_sheet`
/// and `navigation_drawer` do). Kept as a free function so a draw path has one expression for the
/// geometry and a test can compose the same rect without duplicating the arithmetic.
pub(crate) fn scale_about_centre(rect: Rect, scale: f32) -> Rect {
    let scale = scale.clamp(0.0, 1.0);
    let width = ((rect.width as f32 * scale) + 0.5) as u32;
    let height = ((rect.height as f32 * scale) + 0.5) as u32;
    let dx = (rect.width.saturating_sub(width) / 2) as i32;
    let dy = (rect.height.saturating_sub(height) / 2) as i32;
    Rect::new(rect.x + dx, rect.y + dy, width, height)
}