/**
* Shared utilities for parsing and reconstructing Marp markdown files.
*/
/**
* Parses frontmatter from content, separating it from the body.
* If no valid frontmatter exists, the entire file is treated as body content.
*/
export function parseFrontmatter(content: string): { frontmatter: string; body: string } {
const lines = content.split("\n");
if (lines.length === 0) {
return { frontmatter: "", body: "" };
}
if (lines[0].trim() !== "---") {
return { frontmatter: "", body: content };
}
const endIndex = lines.slice(1).findIndex(line => line.trim() === "---");
if (endIndex === -1) {
return { frontmatter: "", body: content };
}
const frontmatterLines = lines.slice(0, endIndex + 2);
const bodyLines = lines.slice(endIndex + 2);
return {
frontmatter: frontmatterLines.join("\n"),
body: bodyLines.join("\n"),
};
}
/**
* Splits the body content into individual slides.
* Handles trailing spaces/tabs after the `---` separator.
*/
export function splitSlides(body: string): string[] {
const trimmed = body.trim();
return trimmed ? trimmed.split(/\n---[ \t]*\n/) : [];
}
/**
* Joins frontmatter and slides back into a single markdown string.
*/
export function joinSlides(frontmatter: string, slides: string[]): string {
if (slides.length === 0) {
return frontmatter.trim() ? frontmatter : "";
}
const processedSlides = slides
.map(s => s.trim())
.filter(s => s !== "");
if (processedSlides.length === 0) {
return frontmatter.trim() ? frontmatter : "";
}
const slidesContent = processedSlides.join("\n\n---\n\n");
if (!frontmatter.trim()) {
return slidesContent;
}
const cleanedFrontmatter = frontmatter.replace(/\s+$/, "");
return `${cleanedFrontmatter}\n\n${slidesContent}`;
}
