3 files changed, 182 insertions, 6 deletions

diff --git a/src/cube_public.h b/src/cube_public.h
index ea1d28d..a1c4b90 100644
--- a/src/cube_public.h
+++ b/src/cube_public.h
@@ -89,7 +89,7 @@ nissy_frommoves(
 }
 
 int64_t
-nissy_convertcube(
+nissy_convert(
         const char *format_in,
         const char *format_out,
         const char *cube_string,
@@ -155,6 +155,7 @@ nissy_solve(
 {
         cube_t c;
         int64_t ret;
+        int h;
 
         c = readcube_B32(cube);
 
@@ -188,8 +189,12 @@ nissy_solve(
                 return -1;
         }
 
-        if (!strcmp(solver, "h48")) {
-                LOG("h48 solver not implemented yet\n");
+        /* TODO define and use solve_options_t */
+        if (!strcmp(solver, "H48")) {
+                h = atoi(options); /* TODO: better parsing */
+                ret = solve_h48(
+                    c, minmoves, maxmoves, maxsolutions,
+                    (uint8_t)h, data, solutions);
                 ret = -1;
         } else if (!strcmp(solver, "simple")) {
                 ret = solve_simple(
diff --git a/src/solve_generic.h b/src/solve_generic.h
index d1d1469..41d995a 100644
--- a/src/solve_generic.h
+++ b/src/solve_generic.h
@@ -21,7 +21,7 @@ solve_generic_appendsolution(dfsarg_generic_t *arg)
 {
         int strl;
 
-        strl = writemoves(arg->moves, arg->depth, *arg->nextsol);
+        strl = writemoves(arg->moves, arg->nmoves, *arg->nextsol);
         LOG("Solution found: %s\n", *arg->nextsol);
         *arg->nextsol += strl;
         **arg->nextsol = '\n';
@@ -53,7 +53,6 @@ solve_generic_dfs(dfsarg_generic_t *arg)
                 return 1;
         }
 
-        /* memcpy(&nextarg, arg, sizeof(dfsarg_generic_t)); */
         nextarg = *arg;
         nextarg.nmoves = arg->nmoves + 1;
         for (m = 0, ret = 0; m < 18; m++) {
diff --git a/src/solve_h48.h b/src/solve_h48.h
index 1646f49..201c7c6 100644
--- a/src/solve_h48.h
+++ b/src/solve_h48.h
@@ -11,6 +11,8 @@
 #define COCLASS(x)            (((x) & COCLASS_MASK) >> UINT32_C(16))
 #define TTREP_MASK            (UINT32_C(0xFF) << UINT32_C(8))
 #define TTREP(x)              (((x) & TTREP_MASK) >> UINT32_C(8))
+#define CBOUND_MASK           UINT32_C(0xFF)
+#define CBOUND(x)             ((x) & CBOUND_MASK)
 #define H48_ESIZE(h)          ((_12c4 * _8c4) << (int64_t)(h))
 
 #define ESEP_IND(i)           ((uint32_t)(i) / UINT32_C(8))
@@ -19,6 +21,8 @@
 #define VISITED_IND(i)        ((uint32_t)(i) / UINT32_C(8))
 #define VISITED_MASK(i)       (UINT32_C(1) << ((uint32_t)(i) % UINT32_C(8)))
 
+#define MAX_SOLUTION_LENGTH 20
+
 typedef struct {
         cube_t cube;
         uint8_t depth;
@@ -39,6 +43,20 @@ typedef struct {
         cube_t *crep;
 } bfsarg_esep_t;
 
+typedef struct {
+        cube_t cube;
+        cube_t inverse;
+        int8_t nmoves;
+        int8_t depth;
+        uint8_t moves[MAX_SOLUTION_LENGTH];
+        int64_t *nsols;
+        int64_t maxsolutions;
+        uint8_t h;
+        uint32_t *cocsepdata;
+        uint32_t *h48data;
+        char **nextsol;
+} dfsarg_solveh48_t;
+
 _static_inline int64_t coord_h48(cube_t, const uint32_t *, uint8_t);
 _static_inline int64_t coord_h48_edges(cube_t, int64_t, uint8_t, uint8_t);
 _static_inline cube_t invcoord_h48(int64_t, const cube_t *, uint8_t);
@@ -53,6 +71,13 @@ _static_inline void set_visited(uint8_t *, int64_t);
 _static_inline uint8_t get_esep_pval(const uint32_t *, int64_t);
 _static_inline void set_esep_pval(uint32_t *, int64_t, uint8_t);
 
+_static void solve_h48_appendsolution(dfsarg_solveh48_t *);
+_static_inline int8_t get_h48_cdata(cube_t, uint32_t *, uint32_t *);
+_static_inline int8_t get_h48_bound(cube_t, uint32_t, uint8_t, uint32_t *);
+_static_inline bool solve_h48_stop(dfsarg_solveh48_t *);
+_static int64_t solve_h48_dfs(dfsarg_solveh48_t *);
+_static int64_t solve_h48(cube_t, int8_t, int8_t, int8_t, uint8_t, const void *, char *);
+
 _static_inline int64_t
 coord_h48(cube_t c, const uint32_t *cocsepdata, uint8_t h)
 {
@@ -238,8 +263,11 @@ gendata_h48(void *buf, uint8_t h, uint8_t maxdepth)
         cube_t crep[COCSEP_CLASSES];
         size_t cocsepsize, infosize;
 
+        /* TODO: move info at start of tables (all tables!) */
         infosize = 4 * maxdepth;
         cocsepsize = gendata_cocsep(buf, selfsim, crep);
+        infosize = 88;
+
         if (buf == NULL)
                 goto gendata_h48_return_size;
 
@@ -272,7 +300,6 @@ gendata_h48(void *buf, uint8_t h, uint8_t maxdepth)
         }
 
         info[0] = arg.depth-1;
-        infosize = 4 * (size_t)(info[0] + 2);
 
         LOG("h48 pruning table computed\n");
         LOG("Maximum pruning value: %" PRIu32 "\n", info[0]);
@@ -353,3 +380,148 @@ set_esep_pval(uint32_t *buf32, int64_t i, uint8_t val)
         buf32[ESEP_IND(i)] =
             (buf32[ESEP_IND(i)] & (~ESEP_MASK(i))) | (val << ESEP_SHIFT(i));
 }
+
+_static void
+solve_h48_appendsolution(dfsarg_solveh48_t *arg)
+{
+        int strl;
+
+        strl = writemoves(arg->moves, arg->nmoves, *arg->nextsol);
+        LOG("Solution found: %s\n", *arg->nextsol);
+        *arg->nextsol += strl;
+        **arg->nextsol = '\n';
+        (*arg->nextsol)++;
+        (*arg->nsols)++;
+}
+
+_static_inline int8_t
+get_h48_cdata(cube_t cube, uint32_t *cocsepdata, uint32_t *cdata)
+{
+        int64_t coord;
+
+        coord = coord_cocsep(cube);
+        *cdata = cocsepdata[coord];
+
+        return CBOUND(*cdata);
+}
+
+_static_inline int8_t
+get_h48_bound(cube_t cube, uint32_t cdata, uint8_t h, uint32_t *h48data)
+{
+        int64_t coord;
+
+        coord = coord_h48_edges(cube, COCLASS(cdata), TTREP(cdata), h);
+        return get_esep_pval(h48data, coord);
+}
+
+_static_inline bool
+solve_h48_stop(dfsarg_solveh48_t *arg)
+{
+        uint32_t data, data_inv;
+        int8_t bound;
+
+        bound = get_h48_cdata(arg->cube, arg->cocsepdata, &data);
+        if (bound + arg->nmoves > arg->depth)
+                return true;
+
+        bound = get_h48_cdata(arg->inverse, arg->cocsepdata, &data_inv);
+        if (bound + arg->nmoves > arg->depth)
+                return true;
+
+/*
+        bound = get_h48_bound(arg->cube, data, arg->h, arg->h48data);
+LOG("Using pval %" PRId8 "\n", bound);
+        if (bound + arg->nmoves > arg->depth)
+                return true;
+
+        bound = get_h48_bound(arg->inverse, data_inv, arg->h, arg->h48data);
+        if (bound + arg->nmoves > arg->depth)
+                return true;
+*/
+
+        return false;
+}
+
+_static int64_t
+solve_h48_dfs(dfsarg_solveh48_t *arg)
+{
+        dfsarg_solveh48_t nextarg;
+        int64_t ret;
+        uint8_t m;
+
+        if (*arg->nsols == arg->maxsolutions)
+                return 0;
+
+        if (solve_h48_stop(arg))
+                return 0;
+
+        if (issolved(arg->cube)) {
+                if (arg->nmoves != arg->depth)
+                        return 0;
+                solve_h48_appendsolution(arg);
+                return 1;
+        }
+
+        /* TODO: avoid copy, change arg and undo changes after recursion */
+        nextarg = *arg;
+        nextarg.nmoves = arg->nmoves + 1;
+        ret = 0;
+        for (m = 0; m < 18; m++) {
+                nextarg.moves[arg->nmoves] = m;
+                if (!allowednextmove(nextarg.moves, nextarg.nmoves)) {
+                        /* If a move is not allowed, neither are its 180
+                         * and 270 degree variations */
+                        m += 2;
+                        continue;
+                }
+                nextarg.cube = move(arg->cube, m);
+                nextarg.inverse = inverse(nextarg.cube); /* TODO: use premove */
+                ret += solve_h48_dfs(&nextarg);
+        }
+
+        return ret;
+}
+
+_static int64_t
+solve_h48(
+        cube_t cube,
+        int8_t minmoves,
+        int8_t maxmoves,
+        int8_t maxsolutions,
+        uint8_t h,
+        const void *data,
+        char *solutions
+)
+{
+        int64_t nsols;
+        dfsarg_solveh48_t arg;
+
+        arg = (dfsarg_solveh48_t) {
+                .cube = cube,
+                .inverse = inverse(cube),
+                .nsols = &nsols,
+                .maxsolutions = maxsolutions,
+                .h = h,
+                .cocsepdata = (uint32_t *)data,
+                .h48data = ((uint32_t *)data) + COCSEP_FULLSIZE / 4,
+                .nextsol = &solutions
+        };
+
+        nsols = 0;
+        for (arg.depth = minmoves;
+             arg.depth <= maxmoves && nsols < maxsolutions;
+             arg.depth++)
+        {
+                LOG("Found %" PRId64 " solutions, searching at depth %"
+                    PRId8 "\n", nsols, arg.depth);
+                arg.nmoves = 0;
+                solve_h48_dfs(&arg);
+        }
+
+/*
+for (int64_t i = 0; i < 4; i++)
+LOG("Data for coord = %" PRId64 ": %" PRIu8 "\n",
+i, get_esep_pval(arg.h48data, i));
+*/
+        return nsols;
+}