🎨 Palette: Implement thousands separators and ANSI line clearing

.Jules/palette.md

@@ -29,3 +29,7 @@
 ## 2025-01-24 - Real-time Achievement Feedback in CLI
 **Learning:** In terminal-based games, displaying achievement progress (like a live high score) in real-time provides immediate tactile reward and engagement. Furthermore, inclusive UX means ensuring first-time players also receive "New Best" feedback, even when their initial record is zero.
 **Action:** Update session-high-score variables immediately upon record-breaking and display them in the live HUD. Ensure achievement conditions (`score > highscore`) don't exclude the first-time user experience.
+
+## 2026-03-31 - Professionalizing CLI UI with Formatting and Line Clearing
+**Learning:** Large numbers in CLI games become hard to read at a glance; implementing thousands separators (like `formatWithCommas`) significantly improves immediate comprehension. Additionally, using the ANSI escape sequence `\033[K` (Erase in Line) is a more robust way to handle volatile line updates than manual space padding, as it avoids "ghost" characters regardless of terminal width or previous string length.
+**Action:** Always format large numeric outputs for readability and use semantic ANSI clearing sequences for in-place terminal updates.

src/main.cpp

@@ -24,6 +24,16 @@
 
 struct termios oldt;
 
+std::string formatWithCommas(long long value) {
+    std::string s = std::to_string(value);
+    int n = s.length() - 3;
+    while (n > 0) {
+        s.insert(n, ",");
+        n -= 3;
+    }
+    return s;
+}
+
 void restore_terminal(int signum) {
     tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
     // Use write() and _exit() because they are async-signal-safe
@@ -77,13 +87,13 @@ int main() {
     std::cout << CLR_CTRL << "==========================\n      SPEED CLICKER\n==========================\n" << CLR_RESET;
 
     if (highscore > 0) {
-        std::cout << " Personal Best: " << CLR_SCORE << highscore << CLR_RESET << "\n\n";
+        std::cout << " Personal Best: " << CLR_SCORE << formatWithCommas(highscore) << CLR_RESET << "\n\n";
     }
 
     std::cout << "Controls:\n " << CLR_CTRL << "[h]" << CLR_RESET << " Toggle Hard Mode (10x Speed!)\n "
               << CLR_CTRL << "[q]" << CLR_RESET << " Quit Game\n " << CLR_CTRL << "[Any key]" << CLR_RESET << " Click!\n\n";
 
-    std::cout << "Press any key to start... " << std::flush;
+    std::cout << "Press " << CLR_CTRL << "any key" << CLR_RESET << " to start... " << std::flush;
     struct pollfd start_fds[1] = {{STDIN_FILENO, POLLIN, 0}};
     if (poll(start_fds, 1, -1) > 0) {
         if (read(STDIN_FILENO, &input, 1) > 0 && input == 'q') {
@@ -94,7 +104,7 @@ int main() {
     }
 
     for (int i = 3; i > 0; --i) {
-        std::cout << "\rStarting in " << CLR_CTRL << i << CLR_RESET << "... " << std::flush;
+        std::cout << "\rStarting in " << CLR_CTRL << i << CLR_RESET << "... \033[K" << std::flush;
         auto start_wait = std::chrono::steady_clock::now();
         while (std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now() - start_wait).count() < 1000) {
             int elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now() - start_wait).count();
@@ -108,7 +118,7 @@ int main() {
             }
         }
     }
-    std::cout << "\r" << CLR_NORM << "GO!             " << CLR_RESET << "\n" << std::flush;
+    std::cout << "\r" << CLR_NORM << "GO!\033[K" << CLR_RESET << "\n" << std::flush;
     std::this_thread::sleep_for(std::chrono::milliseconds(200));
     tcflush(STDIN_FILENO, TCIFLUSH);
 
@@ -141,10 +151,11 @@ int main() {
         }
 
         if (updateUI) {
-            std::cout << "\r" << CLR_SCORE << "Score: " << score << CLR_RESET << " | High: " << highscore << " "
+            std::cout << "\r" << CLR_SCORE << "Score: " << formatWithCommas(score) << CLR_RESET
+                      << " | High: " << formatWithCommas(highscore) << " "
                       << (hardMode ? CLR_HARD "[HARD MODE]" : CLR_NORM "[NORMAL MODE]")
                       << (score > initialHighscore ? " NEW BEST! 🥳" : "")
-                      << "           " << std::flush;
+                      << "\033[K" << std::flush;
             updateUI = false;
         }
     }
@@ -154,9 +165,9 @@ int main() {
     }
 
     tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
-    std::cout << "\n\n" << CLR_SCORE << "Final Score: " << score << CLR_RESET << "\n";
+    std::cout << "\n\n" << CLR_SCORE << "Final Score: " << formatWithCommas(score) << CLR_RESET << "\n";
     if (score > initialHighscore) {
-        std::cout << "Congratulations! A new personal best!\n";
+        std::cout << "Congratulations! A new personal best (Previous: " << formatWithCommas(initialHighscore) << ")!\n";
     }
     std::cout << "Thanks for playing!\n";
     std::cout << "\033[?25h" << std::flush;