Add console clearing capability

This program is expected to be used interactively only. Therefore, we add behavior to the program such that the console is cleared every time the user interacts with the menu. That way, any messages printed because of user input appear at the top and the menu appears again for the user to enter their next interaction, which keeps the UI clean.

NOTE: I originally implemented this behavior in the CSCI 112 project and copied it over to here.

project_3x3_rubik_solver.cpp

@@ -149,6 +149,64 @@ void rightySequence();
 void reverseRightySequence();
 void sledgehammerSequence();
 
+static void clear_console() {
+    /* The definition of `clear_screen()` below is courtesy of
+    https://stackoverflow.com/a/42500322. Please note that the answer has been
+    licensed under CC BY-SA 3.0, and the code has been originally adapted from
+    https://cplusplus.com/articles/4z18T05o/#OSSpecificWays and modified such
+    that it can be cross-compiled and have consistent behavior on all
+    mainstream operating systems. The original licensing from
+    https://cplusplus.com is unknown. */
+#ifdef _WIN32
+    HANDLE                     h_std_out;
+    CONSOLE_SCREEN_BUFFER_INFO csbi;
+    DWORD                      count;
+    DWORD                      cell_count;
+    COORD                      home_coords = { 0, 0 };
+
+    h_std_out = GetStdHandle(STD_OUTPUT_HANDLE);
+    if (h_std_out == INVALID_HANDLE_VALUE) return;
+
+    /* Get the number of cells in the current buffer */
+    if (!GetConsoleScreenBufferInfo(h_std_out, &csbi)) return;
+    cell_count = csbi.dwSize.X * csbi.dwSize.Y;
+
+    /* Fill the entire buffer with spaces */
+    if (!FillConsoleOutputCharacter(
+        h_std_out,
+        (TCHAR)' ',
+        cell_count,
+        home_coords,
+        &count
+    )) return;
+
+    /* Fill the entire buffer with the current colors and attributes */
+    if (!FillConsoleOutputAttribute(
+        h_std_out,
+        csbi.wAttributes,
+        cell_count,
+        home_coords,
+        &count
+    )) return;
+
+    /* Move the cursor home */
+    SetConsoleCursorPosition(h_std_out, home_coords);
+#else
+/* Hassan: Not _WIN32. This assumes that it indicates a POSIX-compatible
+build environment */
+    if (!cur_term)
+    {
+        int result;
+        setupterm(NULL, STDOUT_FILENO, &result);
+        if (result <= 0) return;
+    }
+
+    char action[] = "clear";  /* This was added in order to comply with ISO
+                               * C++11
+                               */
+    putp(tigetstr(action));
+#endif
+}
 
 int main()
 {
@@ -178,6 +236,9 @@ int main()
             continue;  // Will reshow the menu
         }
 
+        /* This program only expects to be used interactively, so buffer
+        cleanliness is important */
+        clear_console();
         // Handle user input
         switch (choice) {
         case 1:

project_3x3_rubik_solver.h

@@ -12,4 +12,13 @@
 #include <vector>
 #include <unordered_map>
 #include <unordered_set>
-#include <queue>
+#include <queue>
+#ifdef _WIN32
+#define NOMINMAX
+#include <Windows.h>
+#else
+#include <curses.h>  // Wasn't included in original code
+                     // https://linux.die.net/man/3/setupterm
+#include <term.h>
+#include <unistd.h>  // Included before `term.h` in original code
+#endif