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//! Traits for fonts and text handling.

use crate::Error;

pub trait Text {
    type FontBuilder: FontBuilder<Out = Self::Font>;
    type Font: Font;

    type TextLayoutBuilder: TextLayoutBuilder<Out = Self::TextLayout>;
    type TextLayout: TextLayout;

    fn new_font_by_name(&mut self, name: &str, size: f64) -> Result<Self::FontBuilder, Error>;

    fn new_text_layout(
        &mut self,
        font: &Self::Font,
        text: &str,
    ) -> Result<Self::TextLayoutBuilder, Error>;
}

pub trait FontBuilder {
    type Out: Font;

    fn build(self) -> Result<Self::Out, Error>;
}

pub trait Font {}

pub trait TextLayoutBuilder {
    type Out: TextLayout;

    fn build(self) -> Result<Self::Out, Error>;
}

pub trait TextLayout {
    /// Measure the advance width of the text.
    fn width(&self) -> f64;
}