TP_13/exo2/lib/coordinates.c

   1 /*
   2  * =====================================================================================
   3  *
   4  *       Filename:  coordinates.c
   5  *
   6  *    Description:  Data definition and functions to manipulate elements in the grid
   7  *
   8  *        Version:  1.0
   9  *        Created:  16/03/2017 19:05:02
  10  *       Revision:  none
  11  *       Compiler:  gcc
  12  *
  13  *         Author:  Jerome Benoit (fraggle), jerome.benoit@piment-noir.org
  14  *   Organization:  Piment Noir
  15  *
  16  * =====================================================================================
  17  */
  18
  19 #include "coordinates.h"
  20
  21 void init_coordinates(coordinates_t* coordinates_array) {
  22
  23     for (unsigned i = 0; i < MAX_COORDINATES; i++) {
  24         coordinates_array[i] = set_coordinates(0, 0, 0);
  25     }
  26 }
  27
  28 void reinit_coordinates(coordinates_t* coordinates_array) {
  29
  30     init_coordinates(coordinates_array);
  31 }
  32
  33 coordinates_t set_coordinates(int y, int x, unsigned type) {
  34     coordinates_t new_coordinates;
  35
  36     new_coordinates.y = y;
  37     new_coordinates.x = x;
  38     new_coordinates.type = type;
  39     return new_coordinates;
  40 }
  41
  42 /* FIXME: Does it worth doing a coordinates_t get_coordinates(int y, int x, unsigned type); helper function? */
  43 /* Or a int get_coordinates_x(int y, int x, unsigned type); helper function? */
  44
  45 /* the function do a lot of sanity checks before adding new board elements,
  46  * hence the loop. moving the checks in the main loop is also possible */
  47 unsigned add_coordinates(coordinates_t new_coordinates, coordinates_t* coordinates_array, unsigned round) {
  48
  49     /* valid coordinates are in the [1-3] range */
  50     if (new_coordinates.y < 1 || new_coordinates.y > 3 || new_coordinates.x < 1 || new_coordinates.x > 3) {
  51         return 3; /* error value for invalid coordinates */
  52     } else if (round == MAX_COORDINATES - 1) {
  53         /* round is off-by-one vs. MAX_COORDINATES */
  54         coordinates_array[MAX_COORDINATES - 1] = new_coordinates;
  55         return 1; /* error value for full array */
  56     }
  57     for (unsigned i = 0; i < MAX_COORDINATES; i++) {
  58         /* check if already entered */
  59         if (new_coordinates.y == (coordinates_array + i)->y && new_coordinates.x == (coordinates_array + i)->x) {
  60             return 2; /* error value for duplicates */
  61         } else if ((coordinates_array + i)->y == 0 && (coordinates_array + i)->x == 0) {
  62             coordinates_array[i] = new_coordinates;
  63             return 0; /* error value when everything if fine */
  64         }
  65     }
  66     return 4; /* error value for unknown error case - should never happen - */
  67 }
  68
  69 static bool chk_line(coordinates_t* coordinates_array, int line_number, unsigned round) {
  70     unsigned nb_o_align = 0;
  71     unsigned nb_x_align = 0;
  72
  73     for (unsigned i = 0; i <= round; i++) {
  74         /* check if they are all the same */
  75         if ((coordinates_array + i)->y == line_number && (coordinates_array + i)->type == 0) {
  76             nb_o_align++;
  77         }
  78         if ((coordinates_array + i)->y == line_number && (coordinates_array + i)->type == 1) {
  79             nb_x_align++;
  80         }
  81     }
  82     if (nb_o_align == 3 || nb_x_align == 3) {
  83         return true;
  84     }
  85     return false;
  86 }
  87
  88 static bool chk_column(coordinates_t* coordinates_array, int column_number, unsigned round) {
  89     unsigned nb_o_align = 0;
  90     unsigned nb_x_align = 0;
  91
  92     for (unsigned i = 0; i <= round; i++) {
  93         /* check if they are all the same */
  94         if ((coordinates_array + i)->x == column_number && (coordinates_array + i)->type == 0) {
  95             nb_o_align++;
  96         }
  97         if ((coordinates_array + i)->x == column_number && (coordinates_array + i)->type == 1) {
  98             nb_x_align++;
  99         }
 100     }
 101     /* one column must be full of the same type */
 102     if (nb_o_align == 3 || nb_x_align == 3) {
 103         return true;
 104     }
 105     return false;
 106 }
 107
 108 static bool chk_diagonals(coordinates_t* coordinates_array, unsigned round) {
 109     unsigned nb_o_diag_one = 0, nb_o_diag_two = 0;
 110     unsigned nb_x_diag_one = 0, nb_x_diag_two = 0;
 111
 112     for (unsigned i = 0; i <= round; i++) {
 113         /* dumb count of each elements type in the two diagonals */
 114         for (int y_x_diag = 1; y_x_diag < 4; y_x_diag++) {
 115             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == y_x_diag && (coordinates_array + i)->type == 0) {
 116                 nb_o_diag_one++;
 117             }
 118             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == (4 - y_x_diag) && (coordinates_array + i)->type == 0) {
 119                 nb_o_diag_two++;
 120             }
 121             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == y_x_diag && (coordinates_array + i)->type == 1) {
 122                 nb_x_diag_one++;
 123             }
 124             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == (4 - y_x_diag) && (coordinates_array + i)->type == 1) {
 125                 nb_x_diag_two++;
 126             }
 127         }
 128         if (nb_o_diag_one == 3 || nb_o_diag_two == 3 || nb_x_diag_one == 3 || nb_x_diag_two == 3) {
 129             return true;
 130         }
 131     }
 132     return false;
 133 }
 134
 135 bool chk_win_conditions(coordinates_t* coordinates_array, unsigned round) {
 136
 137     /* winning conditions begin at round = 4 */
 138     if (round > 3) {
 139         if (chk_diagonals(coordinates_array, round)) {
 140             return true;
 141         }
 142         for (unsigned i = 1; i < 4; i++) {
 143             if (chk_line(coordinates_array, i, round) || \
 144                 chk_column(coordinates_array, i, round)) {
 145                 return true;
 146             }
 147         }
 148     }
 149     return false;
 150 }