Some kind of refactoring

src/services/dict_nav.rs

@@ -0,0 +1,54 @@
+use crate::model::categories;
+use crate::state::{DictFocus, UiState};
+
+pub fn toggle_focus(ui: &mut UiState) {
+    ui.dict_focus = match ui.dict_focus {
+        DictFocus::Categories => DictFocus::Words,
+        DictFocus::Words => DictFocus::Categories,
+    };
+}
+
+pub fn next_category(ui: &mut UiState) {
+    let count = categories::category_count();
+    ui.dict_category = (ui.dict_category + 1) % count;
+}
+
+pub fn prev_category(ui: &mut UiState) {
+    let count = categories::category_count();
+    ui.dict_category = (ui.dict_category + count - 1) % count;
+}
+
+pub fn scroll_down(ui: &mut UiState, n: usize) {
+    let s = ui.dict_scroll_mut();
+    *s = s.saturating_add(n);
+}
+
+pub fn scroll_up(ui: &mut UiState, n: usize) {
+    let s = ui.dict_scroll_mut();
+    *s = s.saturating_sub(n);
+}
+
+pub fn activate_search(ui: &mut UiState) {
+    ui.dict_search_active = true;
+    ui.dict_focus = DictFocus::Words;
+}
+
+pub fn clear_search(ui: &mut UiState) {
+    ui.dict_search_query.clear();
+    ui.dict_search_active = false;
+    *ui.dict_scroll_mut() = 0;
+}
+
+pub fn search_input(ui: &mut UiState, c: char) {
+    ui.dict_search_query.push(c);
+    *ui.dict_scroll_mut() = 0;
+}
+
+pub fn search_backspace(ui: &mut UiState) {
+    ui.dict_search_query.pop();
+    *ui.dict_scroll_mut() = 0;
+}
+
+pub fn search_confirm(ui: &mut UiState) {
+    ui.dict_search_active = false;
+}