= Crystal Markdown :source-highlighter: rouge :toc: preamble

Universal Markdown converter for Crystal. Chains https://github.com/aloli-crystal/crystal-kramdown-asciidoc[crystal-kramdown-asciidoc] with the https://github.com/aloli-crystal/crystal-asciidoctor[crystal-asciidoctor] ecosystem to convert Markdown to PDF, EPUB, HTML, and reveal.js presentations.

== How It Works

Crystal Markdown uses a two-stage pipeline:

. Markdown -> AsciiDoc via crystal-kramdown-asciidoc . AsciiDoc -> Target format via the crystal-asciidoctor ecosystem

This approach leverages the full power of AsciiDoc as an intermediate representation, giving access to the entire Asciidoctor toolchain from a simple Markdown input.

[source,text]

Markdown ──> AsciiDoc ──> HTML ──> PDF ──> EPUB

== Installation

Add the dependency to your shard.yml:

[source,yaml]

dependencies: crystal-markdown: github: aloli-crystal/crystal-markdown version: "~> 0.1"

Then run:

[source,bash]

shards install

== Usage

=== Crystal API

[source,crystal]

require "crystal-markdown"

Markdown to HTML (embedded)

html = CrystalMarkdown.to_html("# Hello\n\nThis is bold.")

Markdown to standalone HTML document

full_html = CrystalMarkdown.to_html_standalone("# Hello\n\nContent.")

Markdown to AsciiDoc

adoc = CrystalMarkdown.to_asciidoc("# Title\n\n- item one\n- item two")

Markdown to PDF file

CrystalMarkdown.to_pdf_file("# Report\n\nContent here.", "report.pdf")

Markdown to PDF bytes

bytes = CrystalMarkdown.to_pdf("# Report\n\nContent here.")

Markdown to EPUB file

CrystalMarkdown.to_epub_file("# Book\n\nChapter content.", "book.epub")

Markdown to EPUB bytes

bytes = CrystalMarkdown.to_epub("# Book\n\nChapter content.")

=== Command Line

[source,bash]

Convert to HTML (default)

crystal-markdown document.md

Convert to PDF

crystal-markdown document.md --to pdf

Convert to EPUB

crystal-markdown document.md --to epub

Convert to AsciiDoc

crystal-markdown document.md --to asciidoc

Specify output file

crystal-markdown document.md --to pdf -o output.pdf

Generate and convert a sample document

crystal-markdown --sample --to pdf -o sample.pdf

== Supported Formats

[cols="1,1,2"] |=== | Format | Extension | Backend

| HTML | .html | crystal-asciidoctor

| PDF | .pdf | crystal-asciidoctor-pdf

| EPUB | .epub | crystal-asciidoctor-epub3

| AsciiDoc | .adoc | crystal-kramdown-asciidoc |===

== Dependencies

• https://github.com/aloli-crystal/crystal-kramdown-asciidoc[crystal-kramdown-asciidoc] -- Markdown to AsciiDoc converter
• https://github.com/aloli-crystal/crystal-asciidoctor[crystal-asciidoctor] -- AsciiDoc parser and HTML converter
• https://github.com/aloli-crystal/crystal-asciidoctor-pdf[crystal-asciidoctor-pdf] -- AsciiDoc to PDF converter
• https://github.com/aloli-crystal/crystal-asciidoctor-epub3[crystal-asciidoctor-epub3] -- AsciiDoc to EPUB converter
• https://github.com/aloli-crystal/crystal-rouge[crystal-rouge] -- Syntax highlighting

== License

MIT -- see link:LICENSE[LICENSE].