Abstract engine and drawing logic apart from one another. Keep gamestate in a struct

src/2048_rewrite.c

@@ -0,0 +1,152 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ncurses.h>
+#include <termios.h>
+#include <unistd.h>
+#include "2048_engine.h"
+
+#define ITER(x, expr)\
+    do {\
+        int i;\
+        for (i = 0; i < x; ++i) { expr; }\
+    } while (0)
+
+#ifdef HAVE_CURSES
+void drawstate_init(void)
+{
+    initscr();
+    cbreak();
+    noecho();
+    curs_set(FALSE);
+}
+
+void drawstate_clear(void)
+{
+    endwin();
+}
+
+void draw_screen(struct gamestate *g)
+{
+    static WINDOW *gamewin;
+    static size_t wh;
+    static size_t ww;
+
+    if (!gamewin) {
+        wh = g->opts->grid_height * (g->print_width + 2) + 3;
+        ww = g->opts->grid_width * (g->print_width + 2) + 1;
+        gamewin = newwin(wh, ww, 1, 1);
+        keypad(gamewin, TRUE);
+    }
+
+    // mvwprintw will sometimes have a useless arg, this is warned, but doesn't affect the program
+    char *scr = g->score_last ? "SCORE: %d (+%d)\n" : "SCORE: %d\n";
+    mvwprintw(gamewin, 0, 0, scr, g->score, g->score_last);
+    mvwprintw(gamewin, 1, 0, "HISCR: %d\n", g->score_high);
+
+    ITER(g->opts->grid_width*(g->print_width + 2) + 1, waddch(gamewin, '-')); 
+    int i, j, xps = 0, yps = 3;
+    for (i = 0; i < g->opts->grid_width; i++, xps = 0, yps++) {
+        mvwprintw(gamewin, yps, xps++, "|");
+        for (j = 0; j < g->opts->grid_height; j++) {
+            if (g->grid[j][i]) {
+                mvwprintw(gamewin, yps, xps, "%*d", g->print_width, g->grid[j][i]);
+                mvwprintw(gamewin, yps, xps + g->print_width, " |");
+            }
+            else {
+                ITER(g->print_width + 1, waddch(gamewin, ' '));
+                waddch(gamewin, '|');
+            }
+            xps += (g->print_width + 2);
+        }
+    }
+    ITER(g->opts->grid_height*(g->print_width + 2) + 1, waddch(gamewin, '-')); 
+    wrefresh(gamewin);
+}
+
+int get_keypress(void)
+{
+    return getch();
+}
+
+#elif VT100_COMPATIBLE
+
+#else
+struct termios sattr;
+void drawstate_clear()
+{
+    tcsetattr(STDIN_FILENO, TCSANOW, &sattr);
+}
+
+void drawstate_init(void)
+{
+    tcgetattr(STDIN_FILENO, &sattr);
+
+    /* alters terminal stdin to not echo and doesn't need \n before reading getchar */
+    struct termios tattr;
+    tcgetattr(STDIN_FILENO, &tattr);
+    tattr.c_lflag &= ~(ICANON | ECHO);
+    tcsetattr(STDOUT_FILENO, TCSANOW, &tattr);
+}
+
+void draw_screen(struct gamestate *g)
+{
+    printf("HISCORE: %ld |", g->score_high);
+    printf("| SCORE: %ld ", g->score);
+    if (g->score_last) printf("(+%ld)", g->score_last);
+    printf("\n");
+
+    // alter this grid_size + 1 to match abitrary grid size
+    ITER(g->opts->grid_width, printf("------"));
+    printf("-\n");
+    int i, j;
+    for (i = 0; i < g->opts->grid_height; i++) {
+        printf("|");
+        for (j = 0; j < g->opts->grid_width; j++) {
+            if (g->grid[j][i])
+                printf("%*ld |", 4, g->grid[j][i]);
+            else
+                printf("     |");
+        }
+        printf("\n");
+    }
+    ITER(g->opts->grid_width, printf("------"));
+    printf("-\n\n");
+}
+
+int get_keypress(void)
+{
+    return fgetc(stdin);
+}
+
+#endif
+
+int main(int argc, char **argv)
+{
+    struct gamestate *g = gamestate_init(gameoptions_default());
+
+    drawstate_init();
+    
+    while (1) {
+        draw_screen(g);
+
+        /* abstract getting keypress */
+        int ch;
+        do {
+            ch = get_keypress();
+            if (ch == 'q') { goto endloop; }
+        } while (strchr("hjkl", ch) == NULL);
+
+        gamestate_tick(g, ch, NULL);
+
+        if (!moves_available(g)) {
+            printf("You lose\n");
+            break;
+        }
+    }
+endloop:
+
+    drawstate_clear();
+    gamestate_clear(g);
+    return 0;
+}