From 383dd7aa4b8cbfda861a7532bd7b3c0df85b3137 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christoffer=20M=C3=BCller=20Madsen?=
 <christoffer@guava.space>
Date: Fri, 11 May 2018 20:13:43 +0200
Subject: [PATCH] code works again; quack gave ~3 times improvement for
 calc_moves

---
 board.py      | 19 ------------
 quack/quack.c | 81 ++++++++++++++++++++++-----------------------------
 2 files changed, 35 insertions(+), 65 deletions(-)

diff --git a/board.py b/board.py
index 6e9aeb1..0f403ed 100644
--- a/board.py
+++ b/board.py
@@ -187,25 +187,6 @@ class Board:
         def calc_moves(board, face_value):
             return quack.calc_moves(board, player, face_value)
 
-            idxs_with_checkers = Board.idxs_with_checkers_of_player(board, player)
-            if len(idxs_with_checkers) == 0:
-                return [board]
-            boards = [(Board.do_move(board,
-                               player,
-                               (idx, idx + (face_value * player)))
-                       if Board.is_move_valid(board,
-                                              player,
-                                              face_value,
-                                              (idx, idx + (face_value * player)))
-                       else None)
-                      for idx in idxs_with_checkers]
-            # print("pls:",boards)
-            board_list = list(filter(None, boards))  # Remove None-values
-            # if len(board_list) == 0:
-            #     return [board]
-            # print("board list:", board_list)
-            return board_list
-
         # Problem with cal_moves: Method can return empty list (should always contain at least same board).
         #               *Update*: Seems to be fixed.
             
diff --git a/quack/quack.c b/quack/quack.c
index 61e3e53..8292f39 100644
--- a/quack/quack.c
+++ b/quack/quack.c
@@ -5,7 +5,7 @@ static PyObject* QuackError;
 typedef struct board_list board_list;
 struct board_list {
   int size;
-  PyObject** list;
+  PyObject* list[16];
 };
 
 /* Utility functions */
@@ -14,11 +14,8 @@ int sign(int x) {
 }
 
 int abs(int x) {
-  if (x >= 0) {
-    return x;
-  } else {
-    return -x;
-  }
+  if (x >= 0) return x;
+  else        return -x;
 }
 /* end utility functions */
 
@@ -124,7 +121,7 @@ int is_move_valid(int board[], int player, int face_value, int move[]) {
     ;
 }
 
-int* do_move(int board[], int player, int move[]) {
+void do_move(int board[], int player, int move[]) {
   int from_idx = move[0];
   int to_idx   = move[1];
 
@@ -132,7 +129,7 @@ int* do_move(int board[], int player, int move[]) {
   board[from_idx] -= player;
 
   /* Return early if bearing off */
-  if (to_idx < 1 || to_idx > 24) return board;
+  if (to_idx < 1 || to_idx > 24) return;
 
   /* Hit opponent checker */
   if (board[to_idx] * player == -1) {
@@ -146,37 +143,39 @@ int* do_move(int board[], int player, int move[]) {
   /* Put down checker */
   board[to_idx] += player;
 
-  return board;
-}
-
-int* do_move_clone(int board[], int player, int move[]) {
-  int new_board[26];
-  for (int i = 0; i < 26; i++) {
-    new_board[i] = board[i];
-  }
-  return do_move(new_board, player, move);
-}
-
-void board_to_pyboard(PyObject* board_tuple, int board[]) {
-  for (int i = 0; i < 26; i++) {
-    PyTuple_SetItem(board_tuple, i, Py_BuildValue("i", board[i]));
-  }
   return;
 }
 
-board_list calc_moves(int board[], int player, int face_value) {
-  int* checker_idxs = idxs_with_checkers_of_player(board, player);
-  board_list boards = { .size = 0,
-			.list = malloc((15 + 1) * sizeof(PyObject*)) };
-  if (boards.list == NULL) {
+int* do_move_clone(int board[], int player, int move[]) {
+  int* new_board = malloc(sizeof(int) * 26);
+  if (new_board == NULL) {
     fprintf(stderr, "malloc failed\n");
     abort();
   }
   
+  for (int i = 0; i < 26; i++) {
+    new_board[i] = board[i];
+  }
+
+  do_move(new_board, player, move);
+  return new_board;
+}
+
+PyObject* store_board_to_pyobject(int board[]) {
+  PyObject* board_tuple = PyTuple_New(26);
+  for (int i = 0; i < 26; i++) {
+    PyTuple_SetItem(board_tuple, i, Py_BuildValue("i", board[i]));
+  }
+  return board_tuple;
+}
+
+board_list calc_moves(int board[], int player, int face_value) {
+  int* checker_idxs = idxs_with_checkers_of_player(board, player);
+  board_list boards = { .size = 0 };
+  
   if (checker_idxs[0] == 0) { 
     boards.size = 1;
-    PyObject* board_tuple = PyTuple_New(26);
-    board_to_pyboard(board_tuple, board);
+    PyObject* board_tuple = store_board_to_pyobject(board);
     boards.list[0] = board_tuple;
     return boards;
   }
@@ -186,27 +185,20 @@ board_list calc_moves(int board[], int player, int face_value) {
     int move[2];
     move[0] = checker_idxs[i];
     move[1] = checker_idxs[i] + (face_value * player);
-    for (int i = 0; i < 2; i++) {
-      printf("move[%i]: %i\n", i, move[i]);
-    }
+
     if (is_move_valid(board, player, face_value, move)) {
-      printf("legal\n");
       int* new_board = do_move_clone(board, player, move);
-      PyObject* board_tuple = PyTuple_New(26);
-      board_to_pyboard(board_tuple, new_board);
+      PyObject* board_tuple = store_board_to_pyobject(new_board);
 
       // segfault maybe :'(
-      //free(new_board);
+      free(new_board);
 
-      boards.list[i] = board_tuple;
+      boards.list[ctr] = board_tuple;
       ctr++;
     }
   }
 
   boards.size = ctr;
-  printf("boards.size: %i\n\n",boards.size);
-
-  
   return boards;
 }
 
@@ -319,8 +311,7 @@ quack_do_move(PyObject *self, PyObject *args) {
 
   do_move(board, player, move);
 
-  PyObject* board_tuple = PyTuple_New(26);
-  board_to_pyboard(board_tuple, board);
+  PyObject* board_tuple = store_board_to_pyobject(board);
   
   return Py_BuildValue("O", board_tuple);
 }
@@ -345,13 +336,11 @@ quack_calc_moves(PyObject *self, PyObject *args) {
   PyObject* boards_list = PyList_New(0);
   
   for (int i = 0; i < boards.size; i++) {
-    printf("%i\n",i);
     if (PyList_Append(boards_list, boards.list[i])) {
       printf("list insertion failed at index %i\n",i);
+      abort();
     }
-    //free(boards.list[i]);
   }
-  //free(boards.list);
   
   return Py_BuildValue("O", boards_list);
 }