Before going crazy

crates/project/src/project.rs

@@ -216,6 +216,12 @@ pub struct Step {
     pub source: Option<usize>,
 }
 
+impl Step {
+    pub fn is_default(&self) -> bool {
+        self.active && self.script.is_empty() && self.source.is_none()
+    }
+}
+
 impl Default for Step {
     fn default() -> Self {
         Self {
@@ -227,20 +233,141 @@ impl Default for Step {
     }
 }
 
-#[derive(Clone, Serialize, Deserialize)]
+#[derive(Clone)]
 pub struct Pattern {
     pub steps: Vec<Step>,
     pub length: usize,
-    #[serde(default)]
     pub speed: PatternSpeed,
-    #[serde(default)]
     pub name: Option<String>,
-    #[serde(default)]
     pub quantization: LaunchQuantization,
-    #[serde(default)]
     pub sync_mode: SyncMode,
 }
 
+#[derive(Serialize, Deserialize)]
+struct SparseStep {
+    i: usize,
+    #[serde(default = "default_active", skip_serializing_if = "is_true")]
+    active: bool,
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    script: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    source: Option<usize>,
+}
+
+fn default_active() -> bool {
+    true
+}
+
+fn is_true(v: &bool) -> bool {
+    *v
+}
+
+#[derive(Serialize, Deserialize)]
+struct SparsePattern {
+    steps: Vec<SparseStep>,
+    length: usize,
+    #[serde(default)]
+    speed: PatternSpeed,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    name: Option<String>,
+    #[serde(default, skip_serializing_if = "is_default_quantization")]
+    quantization: LaunchQuantization,
+    #[serde(default, skip_serializing_if = "is_default_sync_mode")]
+    sync_mode: SyncMode,
+}
+
+fn is_default_quantization(q: &LaunchQuantization) -> bool {
+    *q == LaunchQuantization::default()
+}
+
+fn is_default_sync_mode(s: &SyncMode) -> bool {
+    *s == SyncMode::default()
+}
+
+#[derive(Deserialize)]
+struct LegacyPattern {
+    steps: Vec<Step>,
+    length: usize,
+    #[serde(default)]
+    speed: PatternSpeed,
+    #[serde(default)]
+    name: Option<String>,
+    #[serde(default)]
+    quantization: LaunchQuantization,
+    #[serde(default)]
+    sync_mode: SyncMode,
+}
+
+impl Serialize for Pattern {
+    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        let sparse_steps: Vec<SparseStep> = self
+            .steps
+            .iter()
+            .enumerate()
+            .filter(|(_, step)| !step.is_default())
+            .map(|(i, step)| SparseStep {
+                i,
+                active: step.active,
+                script: step.script.clone(),
+                source: step.source,
+            })
+            .collect();
+
+        let sparse = SparsePattern {
+            steps: sparse_steps,
+            length: self.length,
+            speed: self.speed,
+            name: self.name.clone(),
+            quantization: self.quantization,
+            sync_mode: self.sync_mode,
+        };
+        sparse.serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for Pattern {
+    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        #[derive(Deserialize)]
+        #[serde(untagged)]
+        enum PatternFormat {
+            Sparse(SparsePattern),
+            Legacy(LegacyPattern),
+        }
+
+        match PatternFormat::deserialize(deserializer)? {
+            PatternFormat::Sparse(sparse) => {
+                let mut steps: Vec<Step> = (0..MAX_STEPS).map(|_| Step::default()).collect();
+                for ss in sparse.steps {
+                    if ss.i < MAX_STEPS {
+                        steps[ss.i] = Step {
+                            active: ss.active,
+                            script: ss.script,
+                            command: None,
+                            source: ss.source,
+                        };
+                    }
+                }
+                Ok(Pattern {
+                    steps,
+                    length: sparse.length,
+                    speed: sparse.speed,
+                    name: sparse.name,
+                    quantization: sparse.quantization,
+                    sync_mode: sparse.sync_mode,
+                })
+            }
+            PatternFormat::Legacy(legacy) => Ok(Pattern {
+                steps: legacy.steps,
+                length: legacy.length,
+                speed: legacy.speed,
+                name: legacy.name,
+                quantization: legacy.quantization,
+                sync_mode: legacy.sync_mode,
+            }),
+        }
+    }
+}
+
 impl Default for Pattern {
     fn default() -> Self {
         Self {