merman-render 0.8.0

//! Flowchart v2 icon shape.

use std::fmt::Write as _;

use crate::svg::parity::flowchart::{
    HTML_LABEL_FOREIGN_OBJECT_OVERFLOW_ATTR, OptionalStyleXmlAttr, escape_attr,
    flowchart_label_html,
};
use crate::svg::parity::fmt;

pub(in crate::svg::parity::flowchart::render::node) fn render_icon(
    out: &mut String,
    ctx: &crate::svg::parity::flowchart::types::FlowchartRenderCtx<'_>,
    common: &super::super::FlowchartNodeRenderCommon<'_>,
    label: &super::super::FlowchartNodeLabelState<'_>,
    details: &mut crate::svg::parity::flowchart::types::FlowchartRenderDetails,
) -> crate::Result<()> {
    // Port of Mermaid `icon.ts` (`icon-shape default`).
    let has_label = !label.text.is_empty();
    let label_padding = if has_label { 8.0 } else { 0.0 };
    let top_label = common.node_pos == Some("t");

    let asset_h = common.node_asset_height.unwrap_or(48.0);
    let asset_w = common.node_asset_width.unwrap_or(48.0);
    let icon_size = asset_h.max(asset_w);

    let height = icon_size;
    let width = icon_size;
    let x = -width / 2.0;
    let y = -height / 2.0;
    let metrics = super::super::helpers::compute_node_label_metrics(
        ctx,
        Some(common.layout_node),
        label.text,
        label.label_type,
        common.node_classes,
        common.node_styles,
    );
    let span_style_attr = OptionalStyleXmlAttr(common.label_style);

    // Mermaid's `labelHelper(...)` wraps icon labels in `.labelBkg` (2px padding).
    let label_bbox_w = metrics.width + if has_label { 4.0 } else { 0.0 };
    let label_bbox_h = metrics.height + if has_label { 4.0 } else { 0.0 };
    let label_div_style = super::super::helpers::asset_label_div_style(ctx, label_bbox_w);

    let outer_w = width.max(label_bbox_w);
    let outer_h = height + label_bbox_h + label_padding;

    let icon_dy = if top_label {
        label_bbox_h / 2.0 + label_padding / 2.0
    } else {
        -label_bbox_h / 2.0 - label_padding / 2.0
    };

    // Icon border/background (Mermaid uses RoughJS `rc.rectangle(...)` with stroke/fill "none").
    let icon_path = format!(
        "M{} {} L{} {} L{} {} L{} {}",
        fmt(x),
        fmt(y),
        fmt(x + width),
        fmt(y),
        fmt(x + width),
        fmt(y + height),
        fmt(x),
        fmt(y + height)
    );
    let _ = write!(out, r#"<g transform="translate(0,{})">"#, fmt(icon_dy));
    let _ = write!(
        out,
        r#"<path d="{}" stroke="none" stroke-width="0" fill="none"/>"#,
        escape_attr(&icon_path),
    );
    out.push_str("</g>");

    let outer_x0 = -outer_w / 2.0;
    let outer_y0 = -outer_h / 2.0;
    let outer_path = format!(
        "M{} {} L{} {} L{} {} L{} {}",
        fmt(outer_x0),
        fmt(outer_y0),
        fmt(outer_x0 + outer_w),
        fmt(outer_y0),
        fmt(outer_x0 + outer_w),
        fmt(outer_y0 + outer_h),
        fmt(outer_x0),
        fmt(outer_y0 + outer_h)
    );

    let label_html = super::super::helpers::timed_node_label_html(common.timing, details, || {
        flowchart_label_html(label.text, label.label_type, ctx.config, ctx.math_renderer)
    });
    let label_y = if top_label {
        -outer_h / 2.0
    } else {
        outer_h / 2.0 - label_bbox_h
    };
    let _ = write!(
        out,
        r#"<g class="label" style="{}" transform="translate({},{})"><rect/><foreignObject width="{}" height="{}"{}><div xmlns="http://www.w3.org/1999/xhtml" class="labelBkg" style="{}"><span class="{}"{}>{}</span></div></foreignObject></g>"#,
        escape_attr(common.label_style),
        fmt(-label_bbox_w / 2.0),
        fmt(label_y),
        fmt(label_bbox_w),
        fmt(label_bbox_h),
        HTML_LABEL_FOREIGN_OBJECT_OVERFLOW_ATTR,
        escape_attr(&label_div_style),
        super::super::helpers::flowchart_node_label_span_class(label.label_type),
        span_style_attr,
        label_html
    );

    // Outer bbox helper node (transparent fill, no stroke) — emitted after the label group.
    let _ = write!(
        out,
        r#"<g><path d="{}" stroke="none" stroke-width="0" fill="transparent"/></g>"#,
        escape_attr(&outer_path)
    );

    if let Some(icon_name) = common.node_icon.filter(|icon| !icon.trim().is_empty()) {
        let icon_tx = -icon_size / 2.0;
        let icon_ty = icon_dy - icon_size / 2.0;
        let icon_svg = super::super::helpers::icon_svg_or_placeholder(
            ctx,
            common.node_id,
            icon_name,
            icon_size,
        )?;
        let _ = write!(
            out,
            r#"<g transform="translate({},{})" style="color: {};"><g>{}</g></g>"#,
            fmt(icon_tx),
            fmt(icon_ty),
            escape_attr(common.stroke_color),
            icon_svg,
        );
    }

    out.push_str("</g>");
    if common.wrapped_in_a {
        out.push_str("</a>");
    }
    Ok(())
}