Some kind of refactoring

src/services/pattern_editor.rs

@@ -1,4 +1,4 @@
-use crate::model::{PatternSpeed, Project};
+use crate::model::{Bank, Pattern, PatternSpeed, Project};
 
 #[derive(Debug, Clone, Copy)]
 pub struct PatternEdit {
@@ -90,3 +90,38 @@ pub fn get_step_script(
         .step(step)
         .map(|s| s.script.clone())
 }
+
+pub fn delete_step(project: &mut Project, bank: usize, pattern: usize, step: usize) -> PatternEdit {
+    let pat = project.pattern_at_mut(bank, pattern);
+    for s in &mut pat.steps {
+        if s.source == Some(step) {
+            s.source = None;
+            s.script.clear();
+            s.command = None;
+        }
+    }
+
+    set_step_script(project, bank, pattern, step, String::new());
+    if let Some(s) = project.pattern_at_mut(bank, pattern).step_mut(step) {
+        s.command = None;
+        s.source = None;
+    }
+    PatternEdit::new(bank, pattern)
+}
+
+pub fn delete_steps(project: &mut Project, bank: usize, pattern: usize, steps: &[usize]) -> PatternEdit {
+    for &step in steps {
+        delete_step(project, bank, pattern, step);
+    }
+    PatternEdit::new(bank, pattern)
+}
+
+pub fn reset_pattern(project: &mut Project, bank: usize, pattern: usize) -> PatternEdit {
+    project.banks[bank].patterns[pattern] = Pattern::default();
+    PatternEdit::new(bank, pattern)
+}
+
+pub fn reset_bank(project: &mut Project, bank: usize) -> usize {
+    project.banks[bank] = Bank::default();
+    project.banks[bank].patterns.len()
+}