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-platform/src/accessibility.rs

@@ -0,0 +1,94 @@
+use crate::{env, settings::Motion};
+
+/// `ELY_REDUCE_MOTION` wins, then the setting, then the OS.
+pub fn reduce_motion(setting: Motion) -> bool {
+    let (env, system) = (env::flag("ELY_REDUCE_MOTION"), os_reduce_motion());
+    if env.is_none() && setting == Motion::System && system.is_none() {
+        log::info!("accessibility: no reduce-motion setting found, using full motion");
+    }
+    reduce_motion_from(env, setting, system)
+}
+
+fn reduce_motion_from(env: Option<bool>, setting: Motion, system: Option<bool>) -> bool {
+    let set = match setting {
+        Motion::System => None,
+        Motion::Reduced => Some(true),
+        Motion::Full => Some(false),
+    };
+    env.or(set).or(system).unwrap_or(false)
+}
+
+#[cfg(target_os = "macos")]
+fn os_reduce_motion() -> Option<bool> {
+    Some(objc2_app_kit::NSWorkspace::sharedWorkspace().accessibilityDisplayShouldReduceMotion())
+}
+
+#[cfg(target_os = "linux")]
+fn os_reduce_motion() -> Option<bool> {
+    let output = std::process::Command::new("gsettings")
+        .args(["get", "org.gnome.desktop.interface", "enable-animations"])
+        .output()
+        .map_err(|error| log::debug!("accessibility: gsettings did not run: {error}"))
+        .ok()?;
+    if !output.status.success() {
+        log::debug!("accessibility: gsettings has no enable-animations key");
+        return None;
+    }
+    animations_enabled(&String::from_utf8_lossy(&output.stdout)).map(|enabled| !enabled)
+}
+
+#[cfg(windows)]
+fn os_reduce_motion() -> Option<bool> {
+    use windows_sys::Win32::UI::WindowsAndMessaging::{
+        SPI_GETCLIENTAREAANIMATION, SystemParametersInfoW,
+    };
+
+    let mut enabled: i32 = 1;
+    // SAFETY: a live i32, the size the call expects.
+    let read = unsafe {
+        SystemParametersInfoW(
+            SPI_GETCLIENTAREAANIMATION,
+            0,
+            (&mut enabled as *mut i32).cast(),
+            0,
+        )
+    };
+    (read != 0).then_some(enabled == 0)
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "linux", windows)))]
+fn os_reduce_motion() -> Option<bool> {
+    None
+}
+
+#[cfg(any(target_os = "linux", test))]
+fn animations_enabled(gsettings: &str) -> Option<bool> {
+    match gsettings.trim() {
+        "true" => Some(true),
+        "false" => Some(false),
+        _ => None,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{Motion, animations_enabled, reduce_motion_from};
+
+    #[test]
+    fn the_env_wins_then_the_setting_then_the_os_then_full_motion() {
+        assert!(reduce_motion_from(Some(true), Motion::Full, Some(false)));
+        assert!(!reduce_motion_from(Some(false), Motion::Reduced, Some(true)));
+        assert!(reduce_motion_from(None, Motion::Reduced, Some(false)));
+        assert!(!reduce_motion_from(None, Motion::Full, Some(true)));
+        assert!(reduce_motion_from(None, Motion::System, Some(true)));
+        assert!(!reduce_motion_from(None, Motion::System, None));
+    }
+
+    #[test]
+    fn gsettings_answers_parse_and_anything_else_is_no_answer() {
+        assert_eq!(animations_enabled("true\n"), Some(true));
+        assert_eq!(animations_enabled("false\n"), Some(false));
+        assert_eq!(animations_enabled("uint32 7\n"), None);
+        assert_eq!(animations_enabled(""), None);
+    }
+}