PTN code looks correct, minor tweaks and header guards

5 files changed, 49 insertions, 31 deletions

diff --git a/include/enums.h b/include/enums.h
index 1df2a4b..3f1e172 100644
--- a/include/enums.h
+++ b/include/enums.h
@@ -1,5 +1,8 @@
+#ifndef ENUMS_H_INCLUDE
+#define ENUMS_H_INCLUDE
 enum COLOUR         { C_WHITE, C_BLACK };
 enum STONE_VARIANT  { STONE_FLAT, STONE_STANDING, STONE_CAPSTONE };
 enum MOVE_DIRECTION { M_UP, M_DOWN, M_LEFT, M_RIGHT };
 enum ACTION_RESULT  { A_OK, A_ILLEGAL, A_OVERFLOW };
 enum WIN_RESULT     { W_NONE, W_ROAD_WHITE, W_ROAD_BLACK, W_FLAT_WHITE, W_FLAT_BLACK };
+#endif
diff --git a/include/ptn.c b/include/ptn.c
index 58648b9..1a333d7 100644
--- a/include/ptn.c
+++ b/include/ptn.c
@@ -5,26 +5,28 @@
 
 enum PTN_PARSE_RESULT
 parse_place(const uint8_t board_size, char *ptn,
-            uint8_t *location, enum STONE_VARIANT *stone) {
+            uint8_t *out_location, enum STONE_VARIANT *out_stone) {
+
+  if (board_size < 5 || board_size > 6) return PTN_INVALID;
 
   ASSERT_NONEMPTY;
 
-  *stone = STONE_FLAT;
+  *out_stone = STONE_FLAT;
   switch (*ptn) {
-    case 'C' : { ptn++; *stone = STONE_CAPSTONE; break; };
-    case 'S' : { ptn++; *stone = STONE_STANDING; break; };
+    case 'C' : { ptn++; *out_stone = STONE_CAPSTONE; break; };
+    case 'S' : { ptn++; *out_stone = STONE_STANDING; break; };
     case 'F' : { ptn++; break; };
   }
 
   ASSERT_MORE;
 
   if ( (*ptn < 'a') || (*ptn > '`' + board_size) ) return PTN_INVALID;
-  *location = *ptn - 'a';
+  *out_location = *ptn - 'a';
 
   ptn++; ASSERT_MORE;
 
   if ( (*ptn < '1') || (*ptn > board_size + '0') ) return PTN_INVALID;
-  *location += board_size * (*ptn - '1');
+  *out_location += board_size * (*ptn - '1');
 
   if (*(++ptn) > 0) return PTN_INVALID;
 
@@ -33,8 +35,10 @@ parse_place(const uint8_t board_size, char *ptn,
 
 enum PTN_PARSE_RESULT
 parse_move(const uint8_t board_size, char *ptn,
-           uint8_t *location, enum MOVE_DIRECTION *direction,
-           uint8_t *steps, uint8_t drops[5]) {
+           uint8_t *out_location, enum MOVE_DIRECTION *out_direction,
+           uint8_t *out_steps, uint8_t out_drops[5]) {
+
+  if (board_size < 5 || board_size > 6) return PTN_INVALID;
 
   ASSERT_NONEMPTY;
 
@@ -46,37 +50,47 @@ parse_move(const uint8_t board_size, char *ptn,
   }
 
   if ( (*ptn < 'a') || (*ptn > '`' + board_size) ) return PTN_INVALID;
-  *location = *ptn - 'a';
+  *out_location = *ptn - 'a';
 
   ptn++; ASSERT_MORE;
 
   if ( (*ptn < '1') || (*ptn > board_size + '0') ) return PTN_INVALID;
-  *location += board_size * (*ptn - '1');
+  *out_location += board_size * (*ptn - '1');
 
   ptn++; ASSERT_MORE;
 
   switch (*ptn) {
-    case '+': { *direction = M_UP;    break; }
-    case '-': { *direction = M_DOWN;  break; }
-    case '<': { *direction = M_LEFT;  break; }
-    case '>': { *direction = M_RIGHT; break; }
+    case '+': { *out_direction = M_UP;    break; }
+    case '-': { *out_direction = M_DOWN;  break; }
+    case '<': { *out_direction = M_LEFT;  break; }
+    case '>': { *out_direction = M_RIGHT; break; }
     default: return PTN_INVALID;
   }
 
-  ptn++; ASSERT_MORE;
+  ptn++;
+  // Handle the case '<column><row><direction>' as
+  // '1<column><row><direction>1' for convenience
+  if (*ptn == 0) {
+    if (picked_up == 0) {
+      *out_steps = 1;
+      out_drops[0] = 1;
+    } else {
+      return PTN_INVALID;
+    }
+  }
 
-  *steps = 0;
+  *out_steps = 0;
   uint8_t total = 0;
   while (*ptn) {
       if ( (*ptn < '1') || (*ptn > '0' + board_size) ) {
         return PTN_INVALID;
       }
-      // TODO: Correct?
-      if ( (*steps >= board_size) && *ptn) return PTN_INVALID;
 
-      drops[*steps] = *ptn - '0';
-      total += drops[*steps];
-      *steps += 1;
+      if ( (*out_steps + 1 >= board_size) && *ptn) return PTN_INVALID;
+
+      out_drops[*out_steps] = *ptn - '0';
+      total += out_drops[*out_steps];
+      *out_steps += 1;
       ptn++;
   }
 
diff --git a/include/ptn.h b/include/ptn.h
index 715a7d0..e780a70 100644
--- a/include/ptn.h
+++ b/include/ptn.h
@@ -5,9 +5,9 @@ enum PTN_PARSE_RESULT { PTN_VALID, PTN_INVALID };
 
 enum PTN_PARSE_RESULT
 parse_place(const uint8_t board_size, char *ptn,
-            uint8_t *location, enum STONE_VARIANT *stone);
+            uint8_t *out_location, enum STONE_VARIANT *out_stone);
 
 enum PTN_PARSE_RESULT
 parse_move(const uint8_t board_size, char *ptn,
-           uint8_t *location, enum MOVE_DIRECTION *direction,
-           uint8_t *steps, uint8_t drops[5]);
+           uint8_t *out_location, enum MOVE_DIRECTION *out_direction,
+           uint8_t *out_steps, uint8_t out_drops[5]);
diff --git a/include/state.c b/include/state.c
index 1505881..3708792 100644
--- a/include/state.c
+++ b/include/state.c
@@ -18,14 +18,16 @@
 // -------------------------------------------------------------------
 // Game management
 
-void reset_game() {
-  if (board_size == 6) {
+void reset_state(const uint8_t new_board_size) {
+  if (new_board_size == 6) {
+    board_size = 6;
     white_flats = 30; black_flats = 30;
   } else {
     board_size = 5;
     white_flats = 21; black_flats = 21;
   }
-  white_caps = 1; black_caps = 1;
+  white_caps = 1;
+  black_caps = 1;
 
   turn = 0;
 
diff --git a/include/state.h b/include/state.h
index 428a998..17d705a 100644
--- a/include/state.h
+++ b/include/state.h
@@ -1,16 +1,15 @@
 #include <stdint.h>
 #include "enums.h"
 
-static uint8_t board_size = 5;
-
 typedef uint16_t colour_stack_t;
 typedef uint8_t data_t;
 
-static colour_stack_t colours[36];
+static uint8_t board_size;
 static data_t celldat[36];
+static colour_stack_t colours[36];
 static uint8_t white_flats, black_flats, white_caps, black_caps, turn;
 
-void reset_game(void);
+void reset_state(const uint8_t new_board_size);
 
 enum ACTION_RESULT
 try_place(const int8_t location, const enum COLOUR colour,