Ely Office: six offline-first desktop apps in Rust and GPUI

ElyDoc, ElyTable, ElyShow (LibreOfficeKit), ElyPDF (MuPDF), ElyTree (Git),
ElyMark (Milkdown and CodeMirror in CEF). ElyMail and ElyAgent follow.

crates/ely-web-content/src/edit.rs

@@ -0,0 +1,92 @@
+//! AppKit's Command edit keys; off-screen Blink never gets them.
+
+use cef::*;
+
+const SHIFT: u32 = 1 << 1;
+const CONTROL: u32 = 1 << 2;
+const ALT: u32 = 1 << 3;
+const COMMAND: u32 = 1 << 7;
+
+/// What AppKit's standard bindings do, as page script.
+pub(crate) fn script(windows_key: i32, modifiers: u32) -> Option<String> {
+    if modifiers & COMMAND == 0 || modifiers & (CONTROL | ALT) != 0 {
+        return None;
+    }
+    let alter = if modifiers & SHIFT != 0 {
+        "extend"
+    } else {
+        "move"
+    };
+    let (direction, unit) = match windows_key {
+        0x25 => ("backward", "lineboundary"),
+        0x27 => ("forward", "lineboundary"),
+        0x26 => ("backward", "documentboundary"),
+        0x28 => ("forward", "documentboundary"),
+        // Delete to the line's start or end.
+        0x08 | 0x2E if modifiers & SHIFT == 0 => {
+            let (direction, command) = match windows_key {
+                0x08 => ("backward", "delete"),
+                _ => ("forward", "forwardDelete"),
+            };
+            return Some(format!(
+                "{{const s=getSelection();if(s.isCollapsed)s.modify('extend','{direction}','lineboundary');document.execCommand('{command}')}}"
+            ));
+        }
+        _ => return None,
+    };
+    Some(format!(
+        "{{const s=getSelection();s.modify('{alter}','{direction}','{unit}');s.focusNode?.parentElement?.scrollIntoView({{block:'nearest'}})}}"
+    ))
+}
+
+wrap_keyboard_handler! {
+    pub(crate) struct Keys;
+
+    impl KeyboardHandler {
+        fn on_key_event(
+            &self,
+            browser: Option<&mut Browser>,
+            event: Option<&KeyEvent>,
+            _os_event: *mut u8,
+        ) -> ::std::os::raw::c_int {
+            let (Some(browser), Some(event)) = (browser, event) else { return 0 };
+            let down = matches!(event.type_, KeyEventType::RAWKEYDOWN | KeyEventType::KEYDOWN);
+            if !down || event.focus_on_editable_field == 0 {
+                return 0;
+            }
+            let Some(script) = script(event.windows_key_code, event.modifiers) else { return 0 };
+            let Some(frame) = browser.focused_frame() else { return 0 };
+            log::debug!("web: AppKit edit key {}", event.windows_key_code);
+            frame.execute_java_script(Some(&CefString::from(script.as_str())), None, 0);
+            1
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn command_keys_only() {
+        assert!(
+            script(0x28, COMMAND)
+                .unwrap()
+                .contains("'move','forward','documentboundary'")
+        );
+        assert!(
+            script(0x25, COMMAND | SHIFT)
+                .unwrap()
+                .contains("'extend','backward','lineboundary'")
+        );
+        assert!(
+            script(0x08, COMMAND)
+                .unwrap()
+                .contains("execCommand('delete')")
+        );
+        assert!(script(0x2E, COMMAND).unwrap().contains("forwardDelete"));
+        assert_eq!(script(0x28, 0), None);
+        assert_eq!(script(0x28, COMMAND | ALT), None);
+        assert_eq!(script(0x41, COMMAND), None);
+    }
+}