From 015b6a9dfa8cc28c54775b9ebd65b409066b6188 Mon Sep 17 00:00:00 2001
From: Roman Khaliavka <roman.khaliavka@student.tuke.sk>
Date: Wed, 9 Apr 2025 10:44:45 +0000
Subject: [PATCH] du5

---
 du5/program.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 du5/program.c

diff --git a/du5/program.c b/du5/program.c
new file mode 100644
index 0000000..7f80ddf
--- /dev/null
+++ b/du5/program.c
@@ -0,0 +1,94 @@
+#include "snake.h"
+#include <stdlib.h>
+
+// Pridá nový diel hada na začiatok (hlavu)
+struct snake* add_snake(struct snake* snake, int x, int y){
+    struct snake* new_head = malloc(sizeof(struct snake));
+    if(!new_head){
+      return NULL;
+    }
+    new_head->x = x;
+    new_head->y = y;
+    new_head->next = snake;
+    return new_head;
+}
+
+// Odstráni posledný diel hada (chvost)
+struct snake* remove_snake(struct snake* snake){
+    if(!snake || !snake->next){
+        free(snake);
+        return NULL;
+    }
+
+    struct snake* current = snake;
+    while (current->next && current->next->next){
+        current = current->next;
+    }
+    free(current->next);
+    current->next = NULL;
+    return snake;
+}
+
+// Zistí, či sa na daných súradniciach nachádza časť hada
+int is_snake(struct snake* snake, int x, int y){
+    while(snake){
+        if(snake->x == x && snake->y == y){
+            return 1;
+        }
+        snake = snake->next;
+    }
+    return 0;
+}
+
+// Uvoľní pamäť všetkých častí hada
+void free_snake(struct snake* sn){
+    while(sn){
+        struct snake* next = sn->next;
+        free(sn);
+        sn = next;
+    }
+}
+
+// Spraví jeden krok hry – aktualizuje stav podľa pohybu
+int step_state(struct state* state){
+    if(!state || !state->snake) return END_USER;
+
+    int new_x = state->snake->x + state->sx;
+    int new_y = state->snake->y + state->sy;
+
+    // Kontrola nárazu do steny
+    if(new_x < 0 || new_x >= state->width || new_y < 0 || new_y >= state->height){
+        return END_WALL;
+    }
+
+    // Kontrola nárazu do seba samého
+    if(is_snake(state->snake, new_x, new_y)){
+        return END_SNAKE;
+    }
+
+    // Kontrola, či had zjedol jedlo
+    for(int i = 0; i < FOOD_COUNT; i++){
+        if(state->foodx[i] == new_x && state->foody[i] == new_y){
+            // Označí jedlo ako zjedené
+            state->foodx[i] = -1;
+            state->foody[i] = -1;
+            // Pridá nový diel hada na pozíciu jedla
+            state->snake = add_snake(state->snake, new_x, new_y);
+
+            // Skontroluje, či ešte zostalo jedlo
+            int food_left = 0;
+            for(int j = 0; j < FOOD_COUNT; j++){
+                if(state->foodx[j] >= 0 && state->foody[j] >= 0){
+                    food_left = 1;
+                    break;
+                }
+            }
+            return food_left ? END_CONTINUE : END_FOOD;
+        }
+    }
+
+    // Bežný pohyb – had sa pohne o jedno políčko
+    state->snake = add_snake(state->snake, new_x, new_y);
+    state->snake = remove_snake(state->snake);
+    return END_CONTINUE;
+}