C: Color Settings, Proof Setup and Proof Colors

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/engine/src/cmd/colorsettings.rs

@@ -0,0 +1,101 @@
+//! Edit › Color Settings: the RGB and CMYK working spaces, conversion intent and black-point
+//! compensation (process-wide), and loading ICC profiles.
+
+use designcraft_color::cms::{self, ColorSettings, Intent};
+use serde_json::{Value, json};
+
+use super::{CommandSpec, always, bad, cmd, str_param};
+use crate::Result;
+
+fn state() -> Value {
+    let st = cms::active_settings();
+    json!({"rgb": st.rgb, "cmyk": st.cmyk, "intent": st.intent.id(), "bpc": st.bpc, "profiles": cms::profiles()})
+}
+
+fn set(p: &Value) -> Result<Value> {
+    let mut st: ColorSettings = cms::active_settings();
+    if let Some(v) = str_param(p, "rgb") {
+        st.rgb = v.to_string();
+    }
+    if let Some(v) = str_param(p, "cmyk") {
+        st.cmyk = v.to_string();
+    }
+    if let Some(v) = str_param(p, "intent") {
+        st.intent = Intent::parse(v).ok_or_else(|| bad("color.settings", format!("unknown intent `{v}`")))?;
+    }
+    if let Some(v) = p.get("bpc").and_then(Value::as_bool) {
+        st.bpc = v;
+    }
+    cms::set_active(&st).map_err(|e| bad("color.settings", e.to_string()))?;
+    Ok(state())
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!(
+            noundo "color.settings",
+            "Color Settings",
+            [],
+            None,
+            "{rgb?: working RGB profile, cmyk?: working CMYK profile, intent?: perceptual|relative|saturation|absolute, bpc?: bool} → {rgb, cmyk, intent, bpc, profiles}",
+            always,
+            |_s, p| set(p)
+        ),
+        cmd!(noundo "color.loadProfile", "Load Profile…", [], None, "{path} — an ICC profile (.icc/.icm) to use as a working space or proof target", always, |_s, p| {
+            let path = str_param(p, "path").ok_or_else(|| bad("color.loadProfile", "`path` required"))?;
+            #[cfg(not(target_arch = "wasm32"))]
+            {
+                let info = cms::load_icc_file(std::path::Path::new(path)).map_err(|e| bad("color.loadProfile", e.to_string()))?;
+                Ok(json!(info))
+            }
+            #[cfg(target_arch = "wasm32")]
+            {
+                let _ = path;
+                Err(bad("color.loadProfile", "no file system on the web"))
+            }
+        }),
+        cmd!(query "color.convert", "Convert Color", [], None, "{color: {model: rgb, r, g, b} | {model: cmyk, c, m, y, k} | {model: gray, k}, to: rgb|cmyk|gray|lab} — through the working spaces", always, |_s, p| {
+            let c: designcraft_color::Color = serde_json::from_value(p.get("color").cloned().unwrap_or_default()).map_err(|e| bad("color.convert", e.to_string()))?;
+            let a = cms::active();
+            let intent = a.settings().intent;
+            Ok(match str_param(p, "to").unwrap_or("rgb") {
+                "lab" => {
+                    let l = a.lab(&c);
+                    json!({"l": l.l, "a": l.a, "b": l.b, "outOfGamut": a.out_of_gamut(&c)})
+                }
+                "cmyk" => json!(a.convert(&c, cms::Model::Cmyk, intent)),
+                "gray" => json!(a.convert(&c, cms::Model::Gray, intent)),
+                _ => json!(a.convert(&c, cms::Model::Rgb, intent)),
+            })
+        }),
+    ]
+}
+
+#[cfg(test)]
+mod tests {
+    use serde_json::json;
+
+    use crate::Session;
+
+    #[test]
+    fn color_settings_report_convert_and_validate() {
+        // The settings are process-wide: this test only re-applies the current ones, so tests
+        // rendering in parallel aren't affected.
+        let mut s = Session::new();
+        let before = s.execute("color.settings", &json!({})).unwrap();
+        assert!(before["profiles"].as_array().unwrap().len() >= 6);
+        let cyan = json!({"color": {"model": "cmyk", "c": 1.0, "m": 0.0, "y": 0.0, "k": 0.0}, "to": "rgb"});
+        let rgb = s.execute("color.convert", &cyan).unwrap();
+        assert_eq!(rgb["model"], "rgb");
+        assert!(rgb["r"].as_f64().unwrap() < 0.3 && rgb["b"].as_f64().unwrap() > 0.7, "{rgb}");
+        let lab = s.execute("color.convert", &json!({"color": {"model": "rgb", "r": 0.0, "g": 1.0, "b": 0.0}, "to": "lab"})).unwrap();
+        assert_eq!(lab["outOfGamut"], true, "pure RGB green is outside the press gamut");
+        let again = s
+            .execute("color.settings", &json!({"rgb": before["rgb"], "cmyk": before["cmyk"], "intent": before["intent"], "bpc": before["bpc"]}))
+            .unwrap();
+        assert_eq!(again["cmyk"], before["cmyk"]);
+        assert!(s.execute("color.settings", &json!({"cmyk": "Nope"})).is_err());
+        assert!(s.execute("color.settings", &json!({"intent": "sideways"})).is_err());
+        assert_eq!(s.execute("color.settings", &json!({})).unwrap()["cmyk"], before["cmyk"], "a failed change leaves the settings");
+    }
+}

crates/engine/src/cmd/mod.rs

@@ -7,6 +7,7 @@ pub mod book;
 mod buttons;
 mod captions;
 mod changes;
+mod colorsettings;
 mod conditions;
 mod datamerge;
 mod edit;
@@ -156,6 +157,7 @@ pub fn command_specs() -> &'static [CommandSpec] {
         v.extend(book::specs());
         v.extend(buttons::specs());
         v.extend(captions::specs());
+        v.extend(colorsettings::specs());
         v.extend(changes::specs());
         v.extend(conditions::specs());
         v.extend(library::specs());