From ffbc98e1a28f041581b60b3eb7f6d43cf404214f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christoffer=20M=C3=BCller=20Madsen?=
 <christoffer@guava.space>
Date: Fri, 11 May 2018 19:00:39 +0200
Subject: [PATCH] quack kind of works

---
 quack/quack.c | 239 +++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 199 insertions(+), 40 deletions(-)

diff --git a/quack/quack.c b/quack/quack.c
index b09e722..61e3e53 100644
--- a/quack/quack.c
+++ b/quack/quack.c
@@ -2,6 +2,12 @@
 
 static PyObject* QuackError;
 
+typedef struct board_list board_list;
+struct board_list {
+  int size;
+  PyObject** list;
+};
+
 /* Utility functions */
 int sign(int x) {
     return (x > 0) - (x < 0);
@@ -88,6 +94,8 @@ int can_bear_off(int board[], int player, int from_idx) {
   return 1;
 }
 
+
+
 /* end helper functions */
 
 int is_move_valid(int board[], int player, int face_value, int move[]) {
@@ -116,7 +124,127 @@ int is_move_valid(int board[], int player, int face_value, int move[]) {
     ;
 }
 
+int* do_move(int board[], int player, int move[]) {
+  int from_idx = move[0];
+  int to_idx   = move[1];
+
+  /* "lift" checker */
+  board[from_idx] -= player;
+
+  /* Return early if bearing off */
+  if (to_idx < 1 || to_idx > 24) return board;
+
+  /* Hit opponent checker */
+  if (board[to_idx] * player == -1) {
+    /* Move checker to bar */
+    if (player == 1) board[25] -= player;
+    else             board[0]  -= player;
+
+    board[to_idx] = 0;
+  }
+
+  /* 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) {
+    fprintf(stderr, "malloc failed\n");
+    abort();
+  }
+  
+  if (checker_idxs[0] == 0) { 
+    boards.size = 1;
+    PyObject* board_tuple = PyTuple_New(26);
+    board_to_pyboard(board_tuple, board);
+    boards.list[0] = board_tuple;
+    return boards;
+  }
+
+  int ctr = 0;
+  for (int i = 1; i <= checker_idxs[0]; i++) {
+    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);
+
+      // segfault maybe :'(
+      //free(new_board);
+
+      boards.list[i] = board_tuple;
+      ctr++;
+    }
+  }
+
+  boards.size = ctr;
+  printf("boards.size: %i\n\n",boards.size);
+
+  
+  return boards;
+}
+
 /* Meta definitions */
+int extract_board(int *board, PyObject* board_tuple_obj) {
+  long numValuesBoard;
+  numValuesBoard = PyTuple_Size(board_tuple_obj);
+  if (numValuesBoard != 26) {
+    PyErr_SetString(QuackError, "Board tuple must have 26 entries");
+    return 1;
+  }
+  
+  PyObject* board_val_obj;
+  // Iterate over tuple to retreive positions
+  for (int i=0; i<numValuesBoard; i++) {
+    board_val_obj = PyTuple_GetItem(board_tuple_obj, i);
+    board[i] = PyLong_AsLong(board_val_obj);
+  }
+  
+  return 0;
+}
+
+int extract_move(int *move, PyObject* move_tuple_obj) {
+  long numValuesMove;
+  numValuesMove = PyTuple_Size(move_tuple_obj);
+  if (numValuesMove != 2) {
+    PyErr_SetString(QuackError, "Move tuple must have exactly 2 entries");
+    return 1;
+  }
+  PyObject* move_val_obj;
+  for (int i=0; i<numValuesMove; i++) {
+    move_val_obj = PyTuple_GetItem(move_tuple_obj, i);
+    move[i] = PyLong_AsLong(move_val_obj);
+  }
+
+  return 0;
+}
+
 static PyObject*
 quack_is_move_valid(PyObject *self, PyObject *args) {
   int board[26];
@@ -136,31 +264,8 @@ quack_is_move_valid(PyObject *self, PyObject *args) {
 			 &PyTuple_Type, &move_tuple_obj))
     return NULL;
 
-  long numValuesBoard;
-  numValuesBoard = PyTuple_Size(board_tuple_obj);
-  if (numValuesBoard != 26) {
-    PyErr_SetString(QuackError, "Board tuple must have 26 entries");
-    return NULL;
-  }
-  
-  PyObject* board_val_obj;
-  // Iterate over tuple to retreive positions
-  for (int i=0; i<numValuesBoard; i++) {
-    board_val_obj = PyTuple_GetItem(board_tuple_obj, i);
-    board[i] = PyLong_AsLong(board_val_obj);
-  }
-
-  long numValuesMove;
-  numValuesMove = PyTuple_Size(move_tuple_obj);
-  if (numValuesMove != 2) {
-    PyErr_SetString(QuackError, "Move tuple must have exactly 2 entries");
-    return NULL;
-  }
-  PyObject* move_val_obj;
-  for (int i=0; i<numValuesMove; i++) {
-    move_val_obj = PyTuple_GetItem(move_tuple_obj, i);
-    move[i] = PyLong_AsLong(move_val_obj);
-  }
+ if (extract_board(board, board_tuple_obj)) return NULL;
+ if (extract_move(move, move_tuple_obj))    return NULL;
   
   validity = is_move_valid(board, player, face_value, move);
   return Py_BuildValue("i", validity);
@@ -181,31 +286,76 @@ quack_idxs_with_checkers_of_player(PyObject *self, PyObject *args) {
 			 &player))
     return NULL;
 
-  long numValuesBoard;
-  numValuesBoard = PyTuple_Size(board_tuple_obj);
-  if (numValuesBoard != 26) {
-    PyErr_SetString(QuackError, "Board tuple must have 26 entries");
-    return NULL;
-  }
-  
-  PyObject* board_val_obj;
-  // Iterate over tuple to retreive positions
-  for (int i=0; i<numValuesBoard; i++) {
-    board_val_obj = PyTuple_GetItem(board_tuple_obj, i);
-    board[i] = PyLong_AsLong(board_val_obj);
-  }
+  if (extract_board(board, board_tuple_obj)) return NULL;
   
   idxs = idxs_with_checkers_of_player(board, player);
   PyObject* idxs_list = PyList_New(0);
   
   for (int i = 1; i <= idxs[0]; i++) {
-    PyList_Append(idxs_list, Py_BuildValue("i",idxs[i]));
+    PyList_Append(idxs_list, Py_BuildValue("i", idxs[i]));
   }
   free(idxs);
   
   return Py_BuildValue("O", idxs_list);
 }
 
+static PyObject*
+quack_do_move(PyObject *self, PyObject *args) {
+  int board[26];
+  int player;
+  int move[2];
+  
+  PyObject* board_tuple_obj;
+  PyObject* move_tuple_obj;
+  
+  if (! PyArg_ParseTuple(args, "O!iO!",
+			 &PyTuple_Type, &board_tuple_obj,
+			 &player,
+			 &PyTuple_Type, &move_tuple_obj))
+    return NULL;
+
+  if (extract_board(board, board_tuple_obj)) return NULL;
+  if (extract_move(move, move_tuple_obj))    return NULL;
+
+  do_move(board, player, move);
+
+  PyObject* board_tuple = PyTuple_New(26);
+  board_to_pyboard(board_tuple, board);
+  
+  return Py_BuildValue("O", board_tuple);
+}
+
+static PyObject*
+quack_calc_moves(PyObject *self, PyObject *args) {
+  int board[26];
+  int player;
+  int face_value;
+  
+  PyObject* board_tuple_obj;
+  
+  if (! PyArg_ParseTuple(args, "O!ii",
+			 &PyTuple_Type, &board_tuple_obj,
+			 &player,
+			 &face_value))
+    return NULL;
+
+  if (extract_board(board, board_tuple_obj)) return NULL;
+
+  board_list boards = calc_moves(board, player, face_value);
+  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);
+    }
+    //free(boards.list[i]);
+  }
+  //free(boards.list);
+  
+  return Py_BuildValue("O", boards_list);
+}
+
 
 static PyMethodDef quack_methods[] = {
   {
@@ -214,7 +364,16 @@ static PyMethodDef quack_methods[] = {
   },
   {
     "idxs_with_checkers_of_player", quack_idxs_with_checkers_of_player, METH_VARARGS,
-    "Returnes a list of indexes with checkers of the specified player"},
+    "Returns a list of indexes with checkers of the specified player"
+  },
+  {
+    "do_move", quack_do_move, METH_VARARGS,
+    "Returns the board after doing the specified move"
+  },
+  {
+    "calc_moves", quack_calc_moves, METH_VARARGS,
+    "Calculates all legal moves from board with specified face value"
+  },
   {NULL, NULL, 0, NULL}
 };