use crate::component::ChartComponent;
use crate::layout::LayoutOutput;
use crate::model::{Legend, ResolvedOption};
use crate::visual::{Color, FillStrokeStyle, TextAlign, TextBaseline, VisualElement};
use crate::text::{compute_text_offset, create_text_layout};
use vello_cpu::kurbo::{Point, Rect};
pub struct LegendComponent {
legend: Legend,
}
impl LegendComponent {
pub fn new(legend: &Legend) -> Self {
Self { legend: legend.clone() }
}
}
impl ChartComponent for LegendComponent {
fn build_visual_elements(&self, resolved: &ResolvedOption, layout: &LayoutOutput) -> Vec<VisualElement> {
let mut elements = Vec::new();
if !self.legend.show {
return elements;
}
if let Some(bbox) = layout.legend_bbox {
let item_height = self.legend.item_height;
let symbol_size = self.legend.symbol_size;
let font_config = &self.legend.text_style;
let item_widths: Vec<f64> = self.legend.data.iter()
.map(|name| {
let text_w = crate::layout::measure_text_size(name, font_config).width;
symbol_size + 5.0 + text_w + 10.0
})
.collect();
match self.legend.orient {
crate::model::Orient::Horizontal => {
let mut x = bbox.x0 + 10.0;
let mut y = bbox.y0 + 5.0;
let mut col_count = 0_usize;
for (i, name) in self.legend.data.iter().enumerate() {
let color = resolved.series_color_by_name(name)
.or_else(|| resolved.colors.get(i % resolved.colors.len()).copied())
.unwrap_or(Color::new(0, 0, 0));
let iw = item_widths[i];
if col_count > 0 && x + iw > bbox.x1 - 5.0 {
col_count = 0;
x = bbox.x0 + 10.0;
y += item_height;
}
let center_y = y + item_height / 2.0;
let symbol_y = center_y - symbol_size / 2.0;
elements.push(VisualElement::Rect {
rect: Rect::new(x, symbol_y, x + symbol_size, symbol_y + symbol_size),
style: FillStrokeStyle {
fill: Some(color),
stroke: None,
},
});
let layout_obj = create_text_layout(name, font_config, None);
let (_, y_offset) = compute_text_offset(&layout_obj, TextAlign::Left, TextBaseline::Middle);
elements.push(VisualElement::TextRun {
text: name.clone(),
position: Point::new(x + symbol_size + 5.0, center_y + y_offset),
style: crate::model::TextStyle {
color: font_config.color,
font_size: font_config.font_size,
font_family: font_config.font_family.clone(),
font_weight: font_config.font_weight,
font_style: font_config.font_style,
align: TextAlign::Left,
vertical_align: TextBaseline::Top,
},
rotation: 0.0,
max_width: None,
layout: Some(layout_obj),
});
x += iw;
col_count += 1;
}
}
crate::model::Orient::Vertical => {
for (i, name) in self.legend.data.iter().enumerate() {
let color = resolved.series_color_by_name(name)
.or_else(|| resolved.colors.get(i % resolved.colors.len()).copied())
.unwrap_or(Color::new(0, 0, 0));
let x = bbox.x0 + 10.0;
let y = bbox.y0 + i as f64 * item_height + 5.0;
let center_y = y + item_height / 2.0;
let symbol_y = center_y - symbol_size / 2.0;
elements.push(VisualElement::Rect {
rect: Rect::new(x, symbol_y, x + symbol_size, symbol_y + symbol_size),
style: FillStrokeStyle {
fill: Some(color),
stroke: None,
},
});
let layout_obj = create_text_layout(name, font_config, None);
let (_, y_offset) = compute_text_offset(&layout_obj, TextAlign::Left, TextBaseline::Middle);
elements.push(VisualElement::TextRun {
text: name.clone(),
position: Point::new(x + symbol_size + 5.0, center_y + y_offset),
style: crate::model::TextStyle {
color: font_config.color,
font_size: font_config.font_size,
font_family: font_config.font_family.clone(),
font_weight: font_config.font_weight,
font_style: font_config.font_style,
align: TextAlign::Left,
vertical_align: TextBaseline::Top,
},
rotation: 0.0,
max_width: None,
layout: Some(layout_obj),
});
}
}
}
}
elements
}
}