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 coordinates_t set_coordinates(int y, int x, unsigned type) {
  29     coordinates_t new_coordinates;
  30
  31     new_coordinates.y = y;
  32     new_coordinates.x = x;
  33     new_coordinates.type = type;
  34     return new_coordinates;
  35 }
  36
  37 /* FIXME: Does it worth doing a coordinates_t get_coordinates(int y, int x, unsigned type); helper function? */
  38 /* Or a int get_coordinates_x(int y, int x, unsigned type); helper function? */
  39
  40 /* the function do a lot of sanity checks before adding new board elements,
  41  * hence the loop. moving the checks in the main loop is also possible */
  42 unsigned add_coordinates(coordinates_t new_coordinates, coordinates_t* coordinates_array, unsigned round) {
  43
  44     /* valid coordinates are in the [1-3] range */
  45     if (new_coordinates.y < 1 || new_coordinates.y > 3 || new_coordinates.x < 1 || new_coordinates.x > 3) {
  46         return 3; /* error value for invalid coordinates */
  47     } else if (round == MAX_COORDINATES) {
  48         /* round is off-by-one */
  49         coordinates_array[MAX_COORDINATES - 1] = new_coordinates;
  50         return 1; /* error value for full array */
  51     }
  52     for (unsigned i = 0; i < MAX_COORDINATES; i++) {
  53         /* check if already entered */
  54         if (new_coordinates.y == (coordinates_array + i)->y && new_coordinates.x == (coordinates_array + i)->x) {
  55             return 2; /* error value for duplicates */
  56         } else if ((coordinates_array + i)->y == 0 && (coordinates_array + i)->x == 0) {
  57             coordinates_array[i] = new_coordinates;
  58             return 0; /* error value when everything if fine */
  59         }
  60     }
  61     return 4; /* error value for unknown error case - should never happen - */
  62 }
  63
  64 static bool chk_line(coordinates_t* coordinates_array, int line_number, unsigned round) {
  65     unsigned nb_o_align = 0;
  66     unsigned nb_x_align = 0;
  67
  68     for (unsigned i = 0; i < round; i++) {
  69         /* check if they are all the same */
  70         if ((coordinates_array + i)->y == line_number && (coordinates_array + i)->type == 0) {
  71             nb_o_align++;
  72         }
  73         if ((coordinates_array + i)->y == line_number && (coordinates_array + i)->type == 1) {
  74             nb_x_align++;
  75         }
  76     }
  77     if (nb_o_align == 3 || nb_x_align == 3) {
  78         return true;
  79     }
  80     return false;
  81 }
  82
  83 static bool chk_column(coordinates_t* coordinates_array, int column_number, unsigned round) {
  84     unsigned nb_o_align = 0;
  85     unsigned nb_x_align = 0;
  86
  87     for (unsigned i = 0; i < round; i++) {
  88         /* check if they are all the same */
  89         if ((coordinates_array + i)->x == column_number && (coordinates_array + i)->type == 0) {
  90             nb_o_align++;
  91         }
  92         if ((coordinates_array + i)->x == column_number && (coordinates_array + i)->type == 1) {
  93             nb_x_align++;
  94         }
  95     }
  96     /* one column must be full of the same type */
  97     if (nb_o_align == 3 || nb_x_align == 3) {
  98         return true;
  99     }
 100     return false;
 101 }
 102
 103 static bool chk_diagonals(coordinates_t* coordinates_array, unsigned round) {
 104     unsigned nb_o_diag_one = 0, nb_o_diag_two = 0;
 105     unsigned nb_x_diag_one = 0, nb_x_diag_two = 0;
 106
 107     for (unsigned i = 0; i < round; i++) {
 108         /* dumb count of each elements type in the two diagonals */
 109         for (int y_x_diag = 1; y_x_diag < 4; y_x_diag++) {
 110             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == y_x_diag && (coordinates_array + i)->type == 0) {
 111                 nb_o_diag_one++;
 112             }
 113             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == (4 - y_x_diag) && (coordinates_array + i)->type == 0) {
 114                 nb_o_diag_two++;
 115             }
 116             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == y_x_diag && (coordinates_array + i)->type == 1) {
 117                 nb_x_diag_one++;
 118             }
 119             if ((coordinates_array + i)->y == y_x_diag && (coordinates_array + i)->x == (4 - y_x_diag) && (coordinates_array + i)->type == 1) {
 120                 nb_x_diag_two++;
 121             }
 122         }
 123         if (nb_o_diag_one == 3 || nb_o_diag_two == 3 || nb_x_diag_one == 3 || nb_x_diag_two == 3) {
 124             return true;
 125         }
 126     }
 127     return false;
 128 }
 129
 130 bool chk_win_conditions(coordinates_t* coordinates_array, unsigned round) {
 131
 132     /* winning conditions begin at round = 5 */
 133     if (round > 4) {
 134         if (chk_diagonals(coordinates_array, round)) {
 135             return true;
 136         }
 137         for (unsigned i = 1; i < 4; i++) {
 138             if (chk_line(coordinates_array, i, round) || \
 139                 chk_column(coordinates_array, i, round)) {
 140                 return true;
 141             }
 142         }
 143     }
 144     return false;
 145 }