Separate concerns

1 files changed, 25 insertions, 0 deletions

diff --git a/src/handlers/zoom.rs b/src/handlers/zoom.rs
new file mode 100644
index 0000000..3acbb2c
--- /dev/null
+++ b/src/handlers/zoom.rs
@@ -0,0 +1,25 @@
+use crate::AppModel;
+use crate::constants;
+
+/// Sets the zoom level and updates the rendered image.
+pub fn zoom(model: &mut AppModel, level: f64) {
+    model.zoom = level;
+    model.update_image();
+}
+
+/// Decreases zoom by one step if above minimum.
+pub fn zoom_out(model: &mut AppModel) {
+    let new_zoom = model.zoom - constants::ZOOM_STEP;
+    if new_zoom >= constants::MIN_ZOOM {
+        model.zoom = new_zoom;
+        model.update_image();
+    }
+}
+
+/// Increases zoom by one step if below maximum.
+pub fn zoom_in(model: &mut AppModel) {
+    if model.zoom < constants::MAX_ZOOM {
+        model.zoom += constants::ZOOM_STEP;
+        model.update_image();
+    }
+}