Implement TUI search and mutation workflows

apps/tui/src/search.rs

@@ -0,0 +1,50 @@
+//! Presentation state for storage-provided decrypted search results.
+
+use ironstorage::read::{GrepEntry, GrepResults};
+
+#[derive(Debug)]
+pub struct GrepView {
+    results: GrepResults,
+    selected: Option<usize>,
+}
+
+impl GrepView {
+    pub fn new(results: GrepResults) -> Self {
+        let selected = (!results.entries().is_empty()).then_some(0);
+        Self { results, selected }
+    }
+
+    pub fn entries(&self) -> &[GrepEntry] {
+        self.results.entries()
+    }
+
+    pub fn selected_index(&self) -> Option<usize> {
+        self.selected
+    }
+
+    pub fn selected_entry(&self) -> Option<&GrepEntry> {
+        self.selected
+            .and_then(|index| self.results.entries().get(index))
+    }
+
+    pub fn includes_line_numbers(&self) -> bool {
+        self.results.includes_line_numbers()
+    }
+
+    pub fn next(&mut self) {
+        let count = self.results.entries().len();
+        if count != 0 {
+            self.selected = Some(self.selected.map_or(0, |index| (index + 1) % count));
+        }
+    }
+
+    pub fn previous(&mut self) {
+        let count = self.results.entries().len();
+        if count != 0 {
+            self.selected = Some(
+                self.selected
+                    .map_or(0, |index| index.checked_sub(1).unwrap_or(count - 1)),
+            );
+        }
+    }
+}