wordcraft/crates/engine/src/io_ext.rs

//! Format crates registered with the I/O dispatcher.

use wordcraft_doc::Document;

/// Open a format other than plain text / JSON; files that give no page size (Markdown, HTML)
/// start on `page`.
pub fn open(ext: &str, bytes: &[u8], page: &wordcraft_doc::SectionProps) -> Option<Result<Document, String>> {
    match ext {
        "docx" | "docm" | "dotx" | "dotm" => Some(crate::io::read_docx(bytes, None).map_err(|e| e.to_string())),
        "doc" | "dot" => Some(wordcraft_docbin::read(bytes).map_err(|e| e.to_string())),
        // Word XML Document (Flat OPC) or Word 2003 XML, told apart by the root element.
        "xml" => Some(wordcraft_docx::read_xml(bytes).map_err(|e| e.to_string())),
        // HTML, Markdown, ODT, RTF…: pictures fit the text width (see `io::fit_pictures`).
        other => wordcraft_formats::import_on(other, bytes, page).map(|r| {
            r.map(|mut doc| {
                crate::io::fit_pictures(&mut doc);
                draw_charts(&mut doc);
                doc
            })
        }),
    }
}

/// Draw the charts a reader left undrawn (ODT charts come as their chart model alone): in the
/// document's theme colours, at their size.
fn draw_charts(doc: &mut Document) {
    use wordcraft_doc::para::InlineObject;
    /// Groups nest at most this deep here (the readers flatten deeper ones).
    const DEPTH: usize = 16;
    fn undrawn(o: &InlineObject, depth: usize) -> bool {
        match o {
            InlineObject::Graphic { graphic, .. } => graphic.chart.is_some() && graphic.items.is_empty(),
            InlineObject::Group { children, .. } if depth < DEPTH => children.iter().any(|c| undrawn(&c.obj, depth + 1)),
            _ => false,
        }
    }
    fn draw(o: &mut InlineObject, theme: &[wordcraft_doc::Rgb], depth: usize) {
        match o {
            InlineObject::Group { children, .. } if depth < DEPTH => children.iter_mut().for_each(|c| draw(&mut c.obj, theme, depth + 1)),
            o if undrawn(o, depth) => crate::cmd::chart::redraw(o, theme),
            _ => {}
        }
    }
    let theme = doc.settings.theme_colors.clone();
    // (Drawing them doesn't change the document: markup kept as read for them still is.)
    doc.fill_objects(&|o| undrawn(o, 0), &mut |o| draw(o, &theme, 0));
}

/// Save to a format other than plain text / JSON.
pub fn save(ext: &str, doc: &Document, opts: &crate::io::ExportOptions) -> Option<Result<Vec<u8>, String>> {
    // .docx/.docm/.dotx/.dotm: the extension picks the package flavour Word expects.
    if let Some(flavor) = wordcraft_docx::Flavor::from_ext(ext) {
        return Some(wordcraft_docx::write_as(doc, flavor).map_err(|e| e.to_string()));
    }
    match ext {
        "xml" if opts.word2003 => Some(wordcraft_docx::write_wordml2003(doc).map_err(|e| e.to_string())),
        "xml" => Some(wordcraft_docx::write_flat(doc).map_err(|e| e.to_string())),
        "png" => Some(render_png(doc, 0, 2.0, opts)),
        "pdf" => {
            // Output shows the fields Word fills in as it prints (see `output_fields`).
            let out = crate::cmd::references::output_fields(doc);
            let doc = out.as_ref().unwrap_or(doc);
            let pdf = wordcraft_pdf::PdfOptions {
                include_markup: opts.markup,
                comments: opts.markup && opts.comments,
                numeral: opts.numeral,
                ..Default::default()
            };
            Some(wordcraft_pdf::export(doc, &pdf).map_err(|e| e.to_string()))
        }
        other => wordcraft_formats::export_with(other, doc, &wordcraft_formats::ExportOptions { comments: opts.markup && opts.comments }),
    }
}

/// Render page `page` as PNG at `scale` px/pt. With Print Markup's comments the page has its
/// markup area with the comments in balloons (page images always show tracked changes).
pub fn render_png(doc: &Document, page: usize, scale: f32, opts: &crate::io::ExportOptions) -> Result<Vec<u8>, String> {
    let out = crate::cmd::references::output_fields(doc);
    let doc = out.as_ref().unwrap_or(doc);
    let lo = wordcraft_layout::LayoutOptions { comment_balloons: opts.markup && opts.comments, numeral: opts.numeral, ..Default::default() };
    let l = wordcraft_layout::layout(doc, &mut wordcraft_layout::LayoutCache::new(), &lo);
    let p = l.pages.get(page).ok_or_else(|| format!("no page {}", page + 1))?;
    let img = wordcraft_render::render_page(doc, p, scale, &Default::default());
    Ok(img.to_png())
}