Issue #6 UI: Implement Enter key input handling and boolean return

src/main/java/com/unitime/UI/IntroScreen.java

@@ -0,0 +1,97 @@
+import java.util.Scanner;
+
+public class IntroScreen {
+    //set color for introscreen
+    private static final String ANSI_RESET = "\u001b[0m";
+    private static final String ANSI_BOLD = "\u001b[1m";
+    private static final String ANSI_GREEN = "\u001b[38;5;46m";
+    private static final String ANSI_YELLOW = "\u001b[38;5;226m";
+    private static final String[] ANSI_COLORS = {
+        "\u001b[38;5;196m",
+        "\u001b[38;5;208m",
+        "\u001b[38;5;220m", 
+        "\u001b[38;5;46m", 
+        "\u001b[38;5;51m",  
+        "\u001b[38;5;93m"   
+    };
+    private static final int NUM_COLORS = ANSI_COLORS.length;
+    private static final int WIDTH = 80;
+
+    public static boolean start() {
+        printBorderedBox();
+
+        System.out.println("=".repeat(WIDTH + 4));
+        System.out.println(ANSI_YELLOW + "                      Press [ENTER] to Start UniTime_Solver." + ANSI_RESET);
+        System.out.println("=".repeat(WIDTH + 4));
+
+        //waiting user's enter
+        try (Scanner scanner = new Scanner(System.in)) {
+            scanner.nextLine();
+            return true; //if user's enter succeed
+        }catch (Exception e) {
+            return false; //else
+        }
+    }
+
+    private static void printBorderedBox() {
+        String h_border = "+-" + "-".repeat(WIDTH) + "-+";
+        String emptyLine = "| " + " ".repeat(WIDTH) + " |";
+
+        System.out.println(h_border);
+
+        String title = " ♬  UniTime-Solver";
+        int currentLength = title.length();
+        int padding = WIDTH - currentLength; 
+
+        System.out.println("| " + ANSI_BOLD + title + ANSI_RESET + " ".repeat(padding) + " |");
+        System.out.println(h_border);
+
+        String status = " Status: [ *READY to START* ]"; 
+        int statusPadding = WIDTH - status.length();
+
+
+        System.out.println("| " + ANSI_GREEN + status + ANSI_RESET + " ".repeat(statusPadding) + " |");
+        System.out.println(h_border);
+
+        String[] logo = {
+            "  _   _       _ _____ _                     ____        _                   ",
+
+            " | | | |_ __ (_)_  _ (_)_ __ ___   ___     / ___|  ___ | |_   ______ __ ",
+
+            " | | | | '_ \\| | | | | | '_ ` _ \\ / _ \\____\\___ \\ / _ \\| \\ \\ / /_ \\ '__|",
+
+            " | |_| | | | | | | | | | | | | | |  __/_____|__) | (_) | |\\ V / __/ |  ",
+
+            " \\____/|_| |_|_| |_| |_|_| |_| |_|\\___|    |____/ \\___/|_| \\_/\\___|_|  "
+        };
+
+        final int MAX_LOGO_WIDTH = 72;
+
+        System.out.println(emptyLine);
+
+        for (int i = 0; i < logo.length; i++) {
+            String line = logo[i];
+
+            int leftPadding = (WIDTH - MAX_LOGO_WIDTH) / 2;
+
+            System.out.print("| " + " ".repeat(leftPadding));
+
+            int printableWidth = Math.min(line.length(), MAX_LOGO_WIDTH);
+
+            for (int j = 0; j < printableWidth; j++) {
+                char c = line.charAt(j);
+
+                int colorIndex = (i + j) % NUM_COLORS; 
+
+
+                System.out.print(ANSI_COLORS[colorIndex] + c + ANSI_RESET);
+            }
+
+            int rightPadding = WIDTH - leftPadding - printableWidth;
+            System.out.println(" ".repeat(rightPadding) + " |");
+        }
+
+        System.out.println(emptyLine);
+        System.out.println(h_border);
+    }
+}