Code cleanup on the shot validation path

[Project_algorithmic_C.git] / lib / othello.c

diff --git a/lib/othello.c b/lib/othello.c
index 5d9970c6941a0942d8e948a90541a0a55a06fdbd..857625a1d08befd3868a17b9b9ef20914141445b 100644 (file)
--- a/lib/othello.c
+++ b/lib/othello.c
@@ -24,7 +24,7 @@
 #include "debug.h"
 
 unsigned int current_player(unsigned int round_count) {
-   
+
     if (round_count % 2 != 0) {
         return player_two;
     } else {
@@ -46,11 +46,11 @@ unsigned int current_opponent(unsigned int current_player) {
  * |
  * y
  * |
- * v 
+ * v
  * The origin O has (1, 1) coordinates */
 
 unsigned int get_box_value(int y, int x, unsigned int pawn_array[board_size][board_size]) {
-   
+
     return pawn_array[y-1][x-1];
 }
 
@@ -67,7 +67,7 @@ bool is_box_type(int y, int x, unsigned int pawn_array[board_size][board_size],
 }
 
 static bool is_valid_coordinates(int y, int x) {
-    
+
     if ((y > 0 && y < board_size + 1) && \
             (x > 0 && x < board_size + 1)) {
         return true;
@@ -82,12 +82,12 @@ void set_pawn(int y, int x, unsigned int type, unsigned int pawn_array[board_siz
     if (type > 0 && type < 3 && \
             is_valid_coordinates(y, x)) {
         pawn_array[y-1][x-1] = type;
-    }
+    } //FIXME: else case should set invalid values to permit to catch errors
 }
 
 /* reverse the pawn at (y, x) coordinates if it exists */
 static void reverse_pawn(int y, int x, unsigned int pawn_array[board_size][board_size]) {
-     
+
     if (is_box_type(y, x, pawn_array, black)) {
         set_pawn(y, x, white, pawn_array);
     } else if (is_box_type(y, x, pawn_array, white)) {
@@ -199,7 +199,7 @@ static unsigned int count_pawn_to_reverse_one_direction(int y, int x, int direct
     return nb_pawns_reversed;
 }
 
-/* revert the pawns if needed in one direction */ 
+/* revert the pawns if needed in one direction */
 static unsigned int reverse_one_direction(int y, int x, int direction, unsigned int current_player, unsigned int pawn_array[board_size][board_size], bool dry_run) {
     unsigned int nb_pawns_reversed = 0;
     int moving_y = y, moving_x = x;
@@ -218,20 +218,21 @@ static unsigned int reverse_one_direction(int y, int x, int direction, unsigned
     return nb_pawns_reversed;
 }
 
-/* loop optimized version of valid_shot changing nothing to the pawns 2D array */
-static bool is_legal_shot(int y, int x, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
+/* loop optimized version of valid_shot function changing nothing to the pawns 2D array */
+bool is_legal_shot(int y, int x, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
     unsigned int nb_pawns_reversed = 0;
-    
+
     if (!is_valid_coordinates(y, x) || !is_box_type(y, x, pawn_array, empty)) {
         return false;
     }
-    
+
     for (unsigned int direction = north; direction <= north_west; direction++) {
         nb_pawns_reversed += reverse_one_direction(y, x, direction, current_player, pawn_array, true);
         if (nb_pawns_reversed > 0) {
             return true;
         }
     }
+    return false;
 }
 
 /* play the shot if legal and flip or reverse the necessary pawns */
@@ -245,11 +246,51 @@ unsigned int valid_shot(int y, int x, unsigned int current_player, unsigned int
     for (unsigned int direction = north; direction <= north_west; direction++) {
         nb_pawns_reversed += reverse_one_direction(y, x, direction, current_player, pawn_array, false);
     }
-    
+
     if (nb_pawns_reversed == 0) {
-        return 0;
+        return nb_pawns_reversed;
     }
 
     set_pawn(y, x, current_player, pawn_array);
     return nb_pawns_reversed;
 }
+
+static void add_shots_list_cell(int y, int x, unsigned int type, struct shots_list_s* shots_list) {
+    struct shots_list_s* list_cell = malloc(sizeof(struct shots_list_s));
+    if (!list_cell) {
+        exit(EXIT_FAILURE);
+    }
+
+    if (type > 0 && type < 5 && is_valid_coordinates(y, x)) {
+        list_cell->y = y;
+        list_cell->x = x;
+        list_cell->type = type;
+        list_add_tail(&(list_cell->list), &(shots_list->list));
+    }
+}
+
+void free_shots_list(struct shots_list_s* shots_list) {
+    struct shots_list_s* list_counter;
+
+    while (!list_empty(&shots_list->list)) {
+        list_counter = list_entry(shots_list->list.next, struct shots_list_s, list);
+        list_del(&list_counter->list);
+        free(list_counter);
+    }
+
+}
+
+void build_playable_shots_list(unsigned int current_player, struct shots_list_s* shots_list, unsigned int pawn_array[board_size][board_size]) {
+
+    for (unsigned int i = 0; i <= board_size; i++) {
+        for (unsigned int j = 0; j <= board_size; j++) {
+            if (is_legal_shot(i, j, current_player, pawn_array)) {
+                add_shots_list_cell(i, j, hint_allowed, shots_list);
+            /* FIXME: a neighbourhood detection is needed
+            } else if (is_box_type(i, j, pawn_array, empty)){
+                add_shots_list_cell(i, j, hint_forbidden, shots_list);
+            */
+            }
+        }
+    }
+}