From d18b995228e44c88028412a11ede8c3d9982cae8 Mon Sep 17 00:00:00 2001
From: Austen Adler <agadler@austenadler.com>
Date: Mon, 26 Apr 2021 18:11:23 -0400
Subject: [PATCH] Improve e handling

---
 src/main.rs | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 8c59a0a..322ab03 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -326,6 +326,14 @@ fn handle_key(app: &mut App, events: &Events, key: Key) {
                     app.input.push(c);
                 }
                 Key::Char(c @ 'e') | Key::Char(c @ '.') => {
+                    if app.input.is_empty() {
+                        if let Ok(x) = app.calculator.pop() {
+                            app.input = x.to_string();
+                        } else {
+                            return;
+                        }
+                    }
+
                     if !app.input.contains(c) {
                         app.input.push(c);
                     }
@@ -333,9 +341,16 @@ fn handle_key(app: &mut App, events: &Events, key: Key) {
                 Key::Char('\n') | Key::Char(' ') => {
                     if app.input.is_empty() {
                         calc_operation(app, '\n');
-                    } else if let Ok(f) = app.input.parse::<f64>() {
-                        if app.calculator.push(f).is_ok() {
-                            app.input.clear();
+                    } else {
+                        let mut tmp_input = app.input.clone();
+                        if tmp_input.ends_with('e') {
+                            let tmp_input = tmp_input.push('0');
+                        }
+
+                        if let Ok(f) = tmp_input.parse::<f64>() {
+                            if app.calculator.push(f).is_ok() {
+                                app.input.clear();
+                            }
                         }
                     }
                 }