{} — {n}

//! Reflowable EPUB 3 export (File → Export → EPUB (Reflowable)). //! //! Stories become XHTML in reading order (page, then top-to-bottom, left-to-right of their first //! frame); paragraph styles become CSS classes (`p.`), character styles become `span` //! classes, local overrides become inline styles. Placed graphics become `

", img_src(&name, &a.mime, &a.data), esc(alt)); } } } (body, images, toc) } /// Options for [`export_html`]. #[derive(Clone, Debug, Default)] pub struct HtmlOptions { pub title: Option, pub language: Option, } /// File › Export › HTML: one self-contained page (styles inline, images as data URIs) with the /// document's stories and graphics in reading order. pub fn export_html(doc: &Document, opts: &HtmlOptions) -> String { let title = opts.title.clone().unwrap_or_else(|| doc.title.clone()); let lang = opts.language.clone().unwrap_or_else(|| "en".into()); let (body, _, _) = body_html(doc, &|_, mime, data| format!("data:{mime};base64,{}", base64(data))); format!( "\n\n\n\n\n\n{}\n\n\n\n{body}\n\n", esc(&title), stylesheet(doc) ) } fn base64(data: &[u8]) -> String { const T: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; let mut out = String::with_capacity(data.len().div_ceil(3) * 4); for c in data.chunks(3) { let n = (c[0] as u32) << 16 | (*c.get(1).unwrap_or(&0) as u32) << 8 | *c.get(2).unwrap_or(&0) as u32; for (i, shift) in [18, 12, 6, 0].into_iter().enumerate() { out.push(if i <= c.len() { T[(n >> shift & 63) as usize] as char } else { '=' }); } } out } /// Export the document as a reflowable EPUB 3. pub fn export_epub(doc: &Document, opts: &EpubOptions) -> Result, EpubError> { let io = |e: std::io::Error| EpubError(e.to_string()); let zerr = |e: zip::result::ZipError| EpubError(e.to_string()); let title = opts.title.clone().unwrap_or_else(|| doc.title.clone()); let id = opts.identifier.clone().unwrap_or_else(|| format!("urn:designcraft:{}", slug(&title))); let (body, images, toc) = body_html(doc, &|name, _, _| name.to_string()); let lang = &opts.language; let chapter = format!( "\n\n\n{}\n\n{body}\n\n", esc(&title) ); let mut nav_items = String::new(); for (a, label) in &toc { let _ = write!(nav_items, "

{}

", esc(label)); } if nav_items.is_empty() { nav_items = format!("

{}

", esc(&title)); } let nav = format!( "\n\n\n{}\n\n\n", esc(&title) ); let mut manifest = String::from( "\n\n\n", ); for (k, (name, (mime, _))) in images.iter().enumerate() { let _ = writeln!(manifest, ""); } // Cover: an image page first in reading order. if opts.cover.is_some() { manifest.push_str("\n\n"); } let cover_spine = if opts.cover.is_some() { "\n" } else { "" }; let author = opts.author.as_deref().map(|a| format!("{}", esc(a))).unwrap_or_default(); let opf = format!( "\n\n\n{}\n{}\n{lang}{author}\n2026-01-01T00:00:00Z\n\n\n\n{manifest}\n\n{cover_spine}\n\n\n", esc(&id), esc(&title) ); let container = "\n\n"; let mut buf = std::io::Cursor::new(Vec::new()); { let mut z = zip::ZipWriter::new(&mut buf); let stored = zip::write::SimpleFileOptions::default().compression_method(zip::CompressionMethod::Stored); let deflate = zip::write::SimpleFileOptions::default().compression_method(zip::CompressionMethod::Deflated); z.start_file("mimetype", stored).map_err(zerr)?; z.write_all(b"application/epub+zip").map_err(io)?; for (name, data) in [ ("META-INF/container.xml", container.as_bytes()), ("OEBPS/content.opf", opf.as_bytes()), ("OEBPS/nav.xhtml", nav.as_bytes()), ("OEBPS/style.css", stylesheet(doc).as_bytes()), ("OEBPS/content.xhtml", chapter.as_bytes()), ] { z.start_file(name, deflate).map_err(zerr)?; z.write_all(data).map_err(io)?; } for (name, (_, data)) in &images { z.start_file(format!("OEBPS/{name}"), stored).map_err(zerr)?; z.write_all(data).map_err(io)?; } if let Some(c) = &opts.cover { z.start_file("OEBPS/images/cover.png", stored).map_err(zerr)?; z.write_all(c).map_err(io)?; let xhtml = format!( "\n\n\n{}\n $\"{}\"/$ \n\n", esc(&title), esc(&title) ); z.start_file("OEBPS/cover.xhtml", deflate).map_err(zerr)?; z.write_all(xhtml.as_bytes()).map_err(io)?; } z.finish().map_err(zerr)?; } Ok(buf.into_inner()) } #[cfg(test)] mod tests { use super::*; use designcraft_doc::build::NewDocument; use designcraft_doc::geom::Rect; use designcraft_doc::{ParaFormat, SpreadRef}; use std::io::Read; #[test] fn exports_valid_package_in_reading_order() { let mut d = Document::new(&NewDocument { pages: 2, ..Default::default() }); let lid = d.default_layer(); d.add_text_frame(SpreadRef::Doc(0), Rect::new(36.0, 400.0, 300.0, 500.0), lid, "Second & co", ParaFormat::default()).unwrap(); d.add_text_frame(SpreadRef::Doc(0), Rect::new(36.0, 36.0, 300.0, 100.0), lid, "First\nline two", ParaFormat::default()).unwrap(); let bytes = export_epub(&d, &EpubOptions::default()).unwrap(); let mut z = zip::ZipArchive::new(std::io::Cursor::new(bytes)).unwrap(); assert_eq!(z.by_index(0).unwrap().name(), "mimetype"); let mut html = String::new(); z.by_name("OEBPS/content.xhtml").unwrap().read_to_string(&mut html).unwrap(); let a = html.find("First").unwrap(); let b = html.find("Second <b> & co").unwrap(); assert!(a < b, "reading order"); assert!(html.contains("
")); let mut css = String::new(); z.by_name("OEBPS/style.css").unwrap().read_to_string(&mut css).unwrap(); assert!(css.contains("p.basic-paragraph")); assert!(z.by_name("OEBPS/nav.xhtml").is_ok()); } #[test] fn styles_whose_names_slug_alike_keep_their_own_classes() { let mut d = Document::new(&NewDocument::default()); let lid = d.default_layer(); for (name, size) in [("見出し", 30.0), ("本文", 10.0), ("Body Text", 12.0), ("Body-Text", 20.0)] { d.styles_mut().paragraph.push(designcraft_doc::ParagraphStyle { name: name.into(), based_on: None, next_style: None, para: Default::default(), chars: CharAttrs { size: Some(size), ..Default::default() }, shortcut: String::new(), }); } for (k, name) in ["見出し", "本文", "Body Text", "Body-Text"].into_iter().enumerate() { let y = 36.0 + 100.0 * k as f64; let pf = ParaFormat { style: name.into(), ..Default::default() }; d.add_text_frame(SpreadRef::Doc(0), Rect::new(36.0, y, 300.0, y + 50.0), lid, &format!("P{k}"), pf).unwrap(); } let bytes = export_epub(&d, &EpubOptions::default()).unwrap(); let mut z = zip::ZipArchive::new(std::io::Cursor::new(bytes)).unwrap(); let mut html = String::new(); z.by_name("OEBPS/content.xhtml").unwrap().read_to_string(&mut html).unwrap(); let mut css = String::new(); z.by_name("OEBPS/style.css").unwrap().read_to_string(&mut css).unwrap(); let class_of = |text: &str| { let end = html.find(&format!("\">{text}
")).unwrap(); let start = html[..end].rfind("class=\"").unwrap() + 7; html[start..end].to_string() }; let classes: Vec = (0..4).map(|k| class_of(&format!("P{k}"))).collect(); for (k, c) in classes.iter().enumerate() { assert!(!classes[..k].contains(c), "class `{c}` shared: {classes:?}"); assert_eq!(css.matches(&format!("p.{c} {{")).count(), 1, "one rule for `{c}`:\n{css}"); } } #[test] fn slugs() { assert_eq!(slug("[Basic Paragraph]"), "basic-paragraph"); assert_eq!(slug("Body First"), "body-first"); assert_eq!(slug("1 Head"), "s-1-head"); } #[test] fn html_is_one_self_contained_page() { let mut d = Document::new(&NewDocument::default()); let lid = d.default_layer(); d.add_text_frame(SpreadRef::Doc(0), Rect::new(36.0, 36.0, 300.0, 100.0), lid, "Hello ", ParaFormat::default()).unwrap(); let html = export_html(&d, &HtmlOptions { title: Some("T".into()), language: None }); assert!(html.starts_with("") && html.contains("T") && html.contains("Hello <web>")); assert!(html.contains("p.basic-paragraph"), "styles inline"); assert_eq!(base64(b"Man"), "TWFu"); assert_eq!(base64(b"Ma"), "TWE="); assert_eq!(base64(b"M"), "TQ=="); } }