X-Git-Url: https://git.piment-noir.org/?p=Project_algorithmic_C.git;a=blobdiff_plain;f=lib%2Fothello.c;h=6c03f1dacaa7acbc57c3d55ad51df6e866257b6f;hp=02eac9d82cad3c92011b35f03d4ca30e3e8262fc;hb=aa739af2efbd062790fb7b4690a87e3774efa974;hpb=74e2b93b658575fa792ada51c3bf1cdc3cfde247

diff --git a/lib/othello.c b/lib/othello.c
index 02eac9d..6c03f1d 100644
--- a/lib/othello.c
+++ b/lib/othello.c
@@ -18,11 +18,18 @@
 
 #include <stdlib.h>
 #include <stdbool.h>
+#include <string.h>
 
 #include "othello.h"
+#include "debug.h"
 
+/**
+ * Get current round player integer
+ * @param  round_count current round integer
+ * @return             current round player
+ */
 unsigned int current_player(unsigned int round_count) {
-   
+
     if (round_count % 2 != 0) {
         return player_two;
     } else {
@@ -30,16 +37,38 @@ unsigned int current_player(unsigned int round_count) {
     }
 }
 
-/* for consitency with ncurses, the board coordinates are in the following order:
- * --x-->
+/**
+ * Get current round opponent integer
+ * @param  current_player current round player
+ * @return                current round opponent integer
+ */
+static unsigned int current_opponent(unsigned int current_player) {
+
+    if (current_player == player_one) {
+        return player_two;
+    } else {
+        return player_one;
+    }
+}
+
+/* for consistency with ncurses, the board coordinates are in the following order:
+ * O--x-->
  * |
  * y
  * |
- * v */
+ * v
+ * The origin O has (1, 1) coordinates */
 
+/**
+ * Get pawn value at coordinates (y,x)
+ * @param  y          y coordinate
+ * @param  x          x coordinate
+ * @param  pawn_array array of played pawns
+ * @return            pawn integer type
+ */
 unsigned int get_box_value(int y, int x, unsigned int pawn_array[board_size][board_size]) {
-   
-    return pawn_array[y][x];
+
+    return pawn_array[y-1][x-1];
 }
 
 bool is_box_type(int y, int x, unsigned int pawn_array[board_size][board_size], unsigned int type) {
@@ -54,49 +83,239 @@ bool is_box_type(int y, int x, unsigned int pawn_array[board_size][board_size],
     }
 }
 
-/* helper function to set a value != empty at the (y, x) in the pawns array */
-int** set_pawn(int y, int x, unsigned int type, unsigned int pawn_array[board_size][board_size]) {
+static bool is_valid_coordinates(int y, int x) {
 
-    if (is_box_type(y, x, pawn_array, empty)) {
-        pawn_array[y][x] = type;
-        return pawn_array;
+    if ((y > 0 && y < board_size + 1) && \
+            (x > 0 && x < board_size + 1)) {
+        return true;
     } else {
-        return NULL;
+        return false;
     }
 }
 
-static int** zero_pawns(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++) {
-            pawn_array = set_pawn(i, j, empty, pawn_array);
+/**
+ * Helper function to set a correct value at the (y,x) coordinates in the pawns array
+ * @param y      [description]
+ * @param x      [description]
+ * @param type   [description]
+ * @param pawn_array [description]
+ */
+void set_pawn(int y, int x, unsigned int type, unsigned int pawn_array[board_size][board_size]) {
+
+    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)) {
+        set_pawn(y, x, black, pawn_array);
+    }
+}
+
+void zero_pawns(unsigned int pawn_array[board_size][board_size]) {
+
+    for (int i = 1; i <= board_size; i++) {
+        for (int j = 1; j <= board_size; j++) {
+            set_pawn(i, j, empty, pawn_array);
          }
     }
-    return pawn_array;
 }
 
-/* set the pawns in the start position */
-int** init_pawns(unsigned int pawn_array[board_size][board_size]) {
+/**
+ * Set the pawns in the start position
+ * @param pawn_array array of played pawns
+ */
+void init_pawns(unsigned int pawn_array[board_size][board_size]) {
 
-    pawn_array = zero_pawns(pawn_array);
-    pawn_array = set_pawn(5, 4, black, pawn_array);
-    pawn_array = set_pawn(4, 5, black, pawn_array);
-    pawn_array = set_pawn(4, 4, white, pawn_array);
-    pawn_array = set_pawn(5, 5, white, pawn_array);
-    return pawn_array;
+    /* the 2D array zeroing is not necessary if it is properly initialized to zero */
+    zero_pawns(pawn_array);
+    set_pawn(5, 4, black, pawn_array);
+    set_pawn(4, 5, black, pawn_array);
+    set_pawn(4, 4, white, pawn_array);
+    set_pawn(5, 5, white, pawn_array);
 }
 
-unsigned int count_pawn_type(unsigned int pawn_array[board_size][board_size], unsigned int type) {
+unsigned int count_pawns_type(unsigned int pawn_array[board_size][board_size], unsigned int type) {
     unsigned int count = 0;
 
     if (type > 2) {
-        return -1;
+        return 0;
     }
-    for (unsigned int i = 0; i < board_size; i++) {
-        for (unsigned int j = 0; j < board_size; j++) {
-            if (pawn_array[i][j] == type) {
+    for (int i = 1; i <= board_size; i++) {
+        for (int j = 1; j <= board_size; j++) {
+            if (is_box_type(i, j, pawn_array, type)) {
                 count++;
             }
         }
     }
     return count;
 }
+
+static void direction_to_coordinates(unsigned int direction, int* start_y, int* start_x) {
+
+    if (direction == north) {
+        *start_y = *start_y - 1;
+    } else if (direction == north_east) {
+        *start_y = *start_y - 1;
+        *start_x = *start_x + 1;
+    } else if (direction == east) {
+        *start_x = *start_x + 1;
+    } else if (direction == south_east) {
+        *start_y = *start_y + 1;
+        *start_x = *start_x + 1;
+    } else if (direction == south) {
+        *start_y = *start_y + 1;
+    } else if (direction == south_west) {
+        *start_y = *start_y + 1;
+        *start_x = *start_x - 1;
+    } else if (direction == west) {
+        *start_x = *start_x - 1;
+    } else if (direction == north_west) {
+        *start_y = *start_y - 1;
+        *start_x = *start_x - 1;
+    }
+}
+
+bool is_board_full(unsigned int pawn_array[board_size][board_size]) {
+
+    /* an alternate method is to test the round count vs. 60 */
+    for (int i = 1; i <= board_size; i++) {
+        for (int j = 1; j <= board_size; j++) {
+            if (is_box_type(i, j, pawn_array , empty)) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+unsigned int eval_winner(unsigned int nb_white, unsigned int nb_black) {
+
+    if (nb_white > nb_black) {
+        return player_two;
+    } else if (nb_white < nb_black) {
+        return player_one;
+    } else {
+        return 0;
+    }
+}
+
+static unsigned int count_pawn_to_reverse_one_direction(int y, int x, unsigned int direction, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
+    unsigned int nb_pawns_reversed = 0;
+    int moving_y = y, moving_x = x;
+
+    /* count the pawns to reverse in the chosen direction */
+    direction_to_coordinates(direction, &moving_y, &moving_x);
+    while (true) {
+        if (!is_valid_coordinates(moving_y, moving_x) || is_box_type(moving_y, moving_x, pawn_array, empty)) {
+            return 0;
+        }
+        if (is_box_type(moving_y, moving_x, pawn_array, current_player)) {
+            break;
+        }
+        nb_pawns_reversed++;
+        direction_to_coordinates(direction, &moving_y, &moving_x);
+    }
+    return nb_pawns_reversed;
+}
+
+/* revert the pawns if needed in one direction */
+static unsigned int reverse_one_direction(int y, int x, unsigned 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;
+
+    nb_pawns_reversed = count_pawn_to_reverse_one_direction(moving_y, moving_x, direction, current_player, pawn_array);
+
+    /* now reverse the needed pawns */
+    if (nb_pawns_reversed > 0 && !dry_run) {
+        moving_y = y, moving_x = x;
+        direction_to_coordinates(direction, &moving_y, &moving_x);
+        while (!is_box_type(moving_y, moving_x, pawn_array, current_player)) {
+            reverse_pawn(moving_y, moving_x, pawn_array);
+            direction_to_coordinates(direction, &moving_y, &moving_x);
+        }
+    }
+    return nb_pawns_reversed;
+}
+
+/* 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 */
+unsigned int valid_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 0;
+    }
+
+    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 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 = (struct shots_list_s*)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);
+            */
+            }
+        }
+    }
+}