ttrpg-tools/src/components/journal/stat-sheet.ts

89 lines
2.5 KiB
TypeScript

/**
* Stat sheet template engine — parses *.sheet.svg files and extracts
* text nodes containing ${key} template patterns.
*
* Walks <text> elements. If a <text> has <tspan> children, we bind to
* each <tspan> individually (preserving their position attributes).
* If a <text> has no <tspan> children, we bind to the <text> directly.
*/
/** Regex matching ${key} template patterns (captures the key name). */
const TEMPLATE_RE = /\$\{(\w+)\}/g;
/** A single template binding targeting a specific text-bearing leaf node. */
export interface TextTemplate {
/** The DOM node to update — a <text> (no children) or a <tspan>. */
el: SVGTextContentElement;
/** Original text content with ${key} placeholders. */
template: string;
/** Bare key names extracted from the template. */
keys: string[];
}
/** The result of parsing a stat sheet SVG string. */
export interface ParsedSheet {
svgElement: SVGSVGElement;
templates: TextTemplate[];
}
/**
* Check if a text node's content has template patterns, and if so,
* register a binding.
*/
function scanNode(el: Element, templates: TextTemplate[]): void {
const content = el.textContent;
if (!content) return;
TEMPLATE_RE.lastIndex = 0;
const keys: string[] = [];
let m: RegExpExecArray | null;
while ((m = TEMPLATE_RE.exec(content)) !== null) {
keys.push(m[1]);
}
if (keys.length > 0) {
templates.push({
el: el as SVGTextContentElement,
template: content,
keys,
});
}
}
/**
* Parse an SVG string into a live DOM element and extract all template
* bindings from <text> and <tspan> leaf nodes.
*/
export function parseSheet(svgString: string): ParsedSheet {
const parser = new DOMParser();
const doc = parser.parseFromString(svgString, "image/svg+xml");
const svgElement = doc.documentElement as unknown as SVGSVGElement;
if (!svgElement || svgElement.tagName !== "svg") {
return {
svgElement: document.createElementNS(
"http://www.w3.org/2000/svg",
"svg",
) as SVGSVGElement,
templates: [],
};
}
const templates: TextTemplate[] = [];
for (const textEl of svgElement.querySelectorAll("text")) {
const tspans = textEl.querySelectorAll("tspan");
if (tspans.length > 0) {
// Has children — bind to each <tspan> individually
for (const tspan of tspans) {
scanNode(tspan, templates);
}
} else {
// Leaf <text> — bind directly
scanNode(textEl, templates);
}
}
return { svgElement, templates };
}