Initial Functional Plugin

src/lib.rs

@@ -0,0 +1,167 @@
+use std::{
+    ffi::{CStr, OsStr, c_void},
+    os::unix::ffi::OsStrExt,
+    path::Path,
+};
+
+use cairo::{Format, ImageSurface};
+
+use crate::zathura::{
+    ZathuraResult, cairo_t, zathura_document_get_data, zathura_document_get_path,
+    zathura_document_s, zathura_document_set_data, zathura_document_set_number_of_pages,
+    zathura_page_get_document, zathura_page_get_index, zathura_page_set_height,
+    zathura_page_set_width, zathura_page_t,
+};
+
+mod typst;
+mod zathura;
+use typst::TypstDocument;
+
+#[allow(non_upper_case_globals)]
+#[unsafe(no_mangle)]
+pub static zathura_plugin_6_7: zathura::zathura_plugin_definition_s =
+    zathura::zathura_plugin_definition_s {
+        name: c"zathura-typst".as_ptr(),
+        version: zathura::zathura_plugin_version_s {
+            major: 0,
+            minor: 1,
+            rev: 0,
+        },
+        functions: zathura::zathura_plugin_functions_s {
+            document_open: Some(document_open),
+            document_free: Some(document_free),
+            document_index_generate: None,
+            document_save_as: None,
+            document_attachments_get: None,
+            document_attachment_save: None,
+            document_get_information: None,
+            page_init: Some(page_init),
+            page_clear: Some(page_clear),
+            page_search_text: None,
+            page_links_get: None,
+            page_form_fields_get: None,
+            page_images_get: None,
+            page_image_get_cairo: None,
+            page_get_text: None,
+            page_get_selection: None,
+            page_render_cairo: Some(page_render_cairo),
+            page_get_label: None,
+            page_get_signatures: None,
+        },
+        mime_types_size: 1,
+        mime_types: {
+            static MIMETYPES: &[&u8] = &[c"text/vnd.typst".to_bytes_with_nul().first().unwrap()];
+            MIMETYPES.as_ptr() as *mut _
+        },
+    };
+
+unsafe extern "C" fn document_open(doc: *mut zathura_document_s) -> ZathuraResult {
+    let path = unsafe {
+        Path::new(OsStr::from_bytes(
+            CStr::from_ptr(zathura_document_get_path(doc)).to_bytes(),
+        ))
+    };
+    let Ok(document) = TypstDocument::load(path) else {
+        return ZathuraResult::InvalidArguments;
+    };
+    let document = Box::new(document);
+
+    unsafe {
+        zathura_document_set_number_of_pages(doc, document.doc.pages.len() as _);
+        zathura_document_set_data(doc, Box::into_raw(document) as _);
+    }
+
+    ZathuraResult::OK
+}
+
+unsafe extern "C" fn document_free(_: *mut zathura_document_s, data: *mut c_void) -> ZathuraResult {
+    if !data.is_null() {
+        drop(unsafe { Box::<TypstDocument>::from_raw(data as _) });
+    }
+    ZathuraResult::OK
+}
+
+unsafe extern "C" fn page_init(page: *mut zathura_page_t) -> ZathuraResult {
+    let pageno = unsafe { zathura_page_get_index(page) };
+    let doc = unsafe { zathura_page_get_document(page) };
+    let typst_doc = unsafe { &mut *(zathura_document_get_data(doc) as *mut TypstDocument) };
+    let typst_page = &mut typst_doc.doc.pages[pageno as usize];
+
+    unsafe {
+        zathura_page_set_width(page, typst_page.frame.width().to_pt());
+        zathura_page_set_height(page, typst_page.frame.height().to_pt());
+    };
+
+    ZathuraResult::OK
+}
+
+unsafe extern "C" fn page_clear(_: *mut zathura_page_t, _: *mut c_void) -> ZathuraResult {
+    ZathuraResult::OK
+}
+
+unsafe extern "C" fn page_render_cairo(
+    page: *mut zathura_page_t,
+    _: *mut c_void,
+    cairo: *mut cairo_t,
+    _printing: bool,
+) -> ZathuraResult {
+    let pageno = unsafe { zathura_page_get_index(page) };
+    let doc = unsafe { zathura_page_get_document(page) };
+    let typst_doc = unsafe { &mut *(zathura_document_get_data(doc) as *mut TypstDocument) };
+    let typst_page = &mut typst_doc.doc.pages[pageno as usize];
+
+    let context = unsafe { cairo::Context::from_raw_none(cairo) };
+    let surface = context.target();
+    if surface.status().is_err() {
+        return ZathuraResult::Unknown;
+    }
+    let Ok(surface) = ImageSurface::try_from(surface) else {
+        return ZathuraResult::InvalidArguments;
+    };
+
+    let scale = {
+        let wscale = surface.width() as f32 / typst_page.frame.width().to_pt() as f32;
+        let vscale = surface.height() as f32 / typst_page.frame.height().to_pt() as f32;
+        if wscale < vscale { wscale } else { vscale } // min, but floats aren't Ord
+    };
+
+    let format = surface.format();
+
+    let pixels_rgba = typst_render::render(typst_page, scale).take();
+
+    let (pixels_rgba, _) = pixels_rgba.as_chunks::<4>(); // This will always be exact anyway
+
+    let buf = unsafe {
+        std::slice::from_raw_parts_mut(
+            cairo::ffi::cairo_image_surface_get_data(surface.to_raw_none()),
+            surface.stride() as usize * surface.height() as usize,
+        )
+    };
+
+    if !matches!(format, Format::ARgb32 | Format::Rgb24) {
+        return ZathuraResult::Unknown;
+    }
+
+    pixels_rgba
+        .iter()
+        .zip(buf.chunks_exact_mut(4))
+        .for_each(|(&[r, g, b, a], dst)| {
+            dst.copy_from_slice(&u32::from_be_bytes([a, r, g, b]).to_ne_bytes());
+        });
+
+    surface.mark_dirty();
+
+    ZathuraResult::OK
+}
+// TODO: handle compile errors
+// TODO: render warnings
+// TODO: text/link/... handling
+// TODO: nixify compilation of magicdb (file -Cm ~/.magic:/nix/store/vi7ya34k19nid2m0dmkljqip5572g0bi-file-5.45/share/misc/magic.mgc)
+/*
+0	string/cW	/*\ doc:\ typst\ */	typst text document
+!:ext typ
+!:mime text/vnd.typst
+0	string	#import	typst text document
+!:ext typ
+!:mime text/vnd.typst
+*/