1 files changed, 41 insertions, 0 deletions

diff --git a/src/nissy.h b/src/nissy.h
index 38fe656..959b2d8 100644
--- a/src/nissy.h
+++ b/src/nissy.h
@@ -27,6 +27,7 @@ for example 'rotation UF' or 'mirrored BL'.
 #define NISSY_SIZE_TRANSFORMATION 12U
 #define NISSY_SIZE_SOLVE_STATS    10U
 #define NISSY_SIZE_DATAID         255U
+#define NISSY_SIZE_MOVES          1000U
 
 /* Flags for NISS options */
 #define NISSY_NISSFLAG_NORMAL  1U
@@ -99,6 +100,12 @@ not known.
 #define NISSY_ERROR_INVALID_SOLVER -50LL
 
 /*
+The value NISSY_ERROR_INVALID_VARIATION means that the given method of
+finding variations for a solution is not known.
+*/
+#define NISSY_ERROR_INVALID_VARIATION -51LL
+
+/*
 The value NISSY_ERROR_NULL_POINTER means that one of the provided pointer
 arguments is NULL. For example, it may be returned by solve when called
 with a solver that requires some pre-computed data, but the provided
@@ -205,6 +212,36 @@ nissy_applytrans(
 );
 
 /*
+Find variations of a given move sequence, for example by changing
+the direction of the last quarter turn(s), or linearizing a NISS move
+sequence. The result consists of one or more move sequences, one per line,
+and it always ends in a newline character.
+
+Parameters:
+   moves       - The moves of which to find the variation. Must be at most
+                 NISSY_SIZE_MOVES long.
+   variations  - Specify which kind of variations to find, e.g. "lastqt".
+   result_size - The size of the result buffer.
+   result      - The result buffer.
+
+Return values:
+   NISSY_ERROR_NULL_POINTER      - One of the provided pointers is NULL.
+   NISSY_ERROR_INVALID_MOVES     - The given moves are invalid.
+   NISSY_ERROR_INVALID_VARIATION - The given transformer is not known.
+   NISSY_ERROR_BUFFER_SIZE       - Either the result buffer is too small or the
+                                   given move sequence is longer than
+                                   NISSY_SIZE_MOVES.
+   Any value >= 0                - The number of variations found.
+*/
+long long
+nissy_variations(
+        const char *moves,
+        const char *variation,
+        unsigned long long result_size,
+        char *result
+);
+
+/*
 Get the cube with the given ep, eo, cp and co values. The values must be in the
 ranges specified below, but if the option "fix" is given any values outside its
 range will be adjusted before using it. The option "fix" also fixes parity and
@@ -365,6 +402,8 @@ nissy_solve(
 );
 
 /*
+Count the given moves.
+
 Parameters:
    moves  - The moves to be counted.
 
@@ -379,6 +418,8 @@ nissy_countmoves(
 );
 
 /*
+Compare the two moves sequences. Both must be at most NISSY_SIZE_MOVES long.
+
 Parameters:
    moves1 - The first sequence of moves to compare.
    moves2 - The second sequence of moves to compare.