playout/moggy.c

   1 /* Playout policy by stochastically applying a fixed set of decision
   2  * rules in given order - modelled after the intelligent playouts
   3  * in the Mogo engine. */
   4
   5 #include <assert.h>
   6 #include <math.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9
  10 #define DEBUG
  11 #include "board.h"
  12 #include "debug.h"
  13 #include "joseki/base.h"
  14 #include "mq.h"
  15 #include "pattern3.h"
  16 #include "playout.h"
  17 #include "playout/moggy.h"
  18 #include "random.h"
  19 #include "tactics.h"
  20 #include "uct/prior.h"
  21
  22 #define PLDEBUGL(n) DEBUGL_(p->debug_level, n)
  23
  24 /* Whether to avoid capturing/atariing doomed groups (this is big
  25  * performance hit and may reduce playouts balance; it does increase
  26  * the strength, but not quite proportionally to the performance). */
  27 //#define NO_DOOMED_GROUPS
  28
  29
  30 /* Note that the context can be shared by multiple threads! */
  31
  32 struct moggy_policy {
  33         bool ladders, ladderassess, borderladders, assess_local;
  34         unsigned int lcapturerate, atarirate, capturerate, patternrate, korate, josekirate;
  35         unsigned int selfatarirate, alwaysccaprate;
  36         unsigned int fillboardtries;
  37         int koage;
  38         /* Whether to look for patterns around second-to-last move. */
  39         bool pattern2;
  40         /* Whether, when self-atari attempt is detected, to play the other
  41          * group's liberty if that is non-self-atari. */
  42         bool selfatari_other;
  43
  44         struct pattern3s patterns;
  45 };
  46
  47
  48 struct group_state {
  49         enum {
  50                 G_ATARI,
  51                 G_2LIB, /* Unused. */
  52                 G_SAFE /* Unused. */
  53         } status:2;
  54
  55         /* Below, we keep track of each trait for each |color_to_play */
  56         int capturable_ready:2; // is @capturable meaningful?
  57         int capturable:2;
  58
  59         int can_countercapture_ready:2;
  60         int can_countercapture:2;
  61 };
  62
  63 /* Cache of evaluation of various board features. */
  64 struct board_state {
  65         int bsize2;
  66         hash_t hash;
  67         struct group_state *groups; /* [board_size2()], indexed by group_t */
  68         unsigned char *groups_known; /* Bitmap of known groups. */
  69 };
  70
  71 /* Using board cache: this turns out to be actually a 10% slowdown,
  72  * since we reuse data in the cache only very little within single
  73  * move. */
  74 // #define CACHE_STATE
  75 /* Reusing board cache across moves if they are successive on the
  76  * board; only cache entries within cfg distance 2 of the last move
  77  * are cleared. */
  78 // #define PERSISTENT_STATE
  79
  80 #ifdef CACHE_STATE
  81 static __thread struct board_state *ss;
  82
  83 static bool
  84 board_state_reuse(struct board_state *s, struct board *b)
  85 {
  86         /* Decide how much of the board state we can reuse. */
  87         /* We do not cache ladder decisions, so we don't have
  88          * to worry about this. */
  89         coord_t c = b->last_move.coord;
  90
  91         if (unlikely(is_pass(c))) {
  92                 /* Passes don't change anything. */
  93                 return true;
  94         }
  95
  96         if (unlikely(board_at(b, c) == S_NONE)) {
  97                 /* Suicide is hopeless. */
  98                 return false;
  99         }
 100
 101         /* XXX: we can make some moves self-atari. */
 102
 103         if (neighbor_count_at(b, c, S_BLACK) + neighbor_count_at(b, c, S_WHITE) == 0) {
 104                 /* We are not taking off liberties of any other stones. */
 105                 return true;
 106         }
 107
 108         return false;
 109 }
 110
 111 static inline struct board_state *
 112 board_state_init(struct board *b)
 113 {
 114         if (ss) {
 115                 if (ss->bsize2 != board_size2(b)) {
 116                         free(ss->groups);
 117                         free(ss->groups_known);
 118                         free(ss); ss = NULL;
 119                 }
 120 #ifdef PERSISTENT_STATE
 121                 /* Only one stone added to the board, nothing removed. */
 122                 else if (ss->hash == (b->hash ^ hash_at(b, b->last_move.coord, b->last_move.color))) {
 123                         ss->hash = b->hash;
 124                         if (likely(board_state_reuse(ss, b)))
 125                                 return ss;
 126                 }
 127 #endif
 128         }
 129         if (!ss) {
 130                 ss = malloc2(sizeof(*ss));
 131                 ss->bsize2 = board_size2(b);
 132                 ss->groups = malloc2(board_size2(b) * sizeof(*ss->groups));
 133                 ss->groups_known = malloc2(board_size2(b) / 8 + 1);
 134         }
 135         ss->hash = b->hash;
 136         memset(ss->groups_known, 0, board_size2(b) / 8 + 1);
 137         return ss;
 138 }
 139
 140 #define group_is_known(s, g) (s->groups_known[g >> 3] & (1 << (g & 7)))
 141 #define group_set_known(s, g) (s->groups_known[g >> 3] |= (1 << (g & 7)))
 142 #define group_trait_ready(s, g, color, gstat, trait) do { \
 143         if (!group_is_known(s, g)) { \
 144                 memset(&s->groups[g], 0, sizeof(s->groups[g])); \
 145                 group_set_known(s, g); \
 146         } \
 147         s->groups[g].status = gstat; \
 148         s->groups[g].trait ## _ready |= color; \
 149 } while (0)
 150 #define group_trait_is_ready(s, g, color, trait) (s->groups[g].trait ## _ready & color)
 151 #define group_trait_set(s, g, color, trait, val) s->groups[g].trait = (s->groups[g].trait & ~color) | (!!val * color)
 152 #define group_trait_get(s, g, color, trait) (s->groups[g].trait & color)
 153
 154 #else
 155
 156 #define board_state_init(b) NULL
 157 #define group_is_known(s, g) false
 158 #define group_set_known(s, g)
 159 #define group_trait_ready(s, g, color, gstat, trait)
 160 #define group_trait_is_ready(s, g, color, trait) false
 161 #define group_trait_set(s, g, color, trait, val)
 162 #define group_trait_get(s, g, color, trait) false
 163 #endif
 164
 165
 166 static char moggy_patterns_src[][11] = {
 167         /* hane pattern - enclosing hane */
 168         "XOX"
 169         "..."
 170         "???",
 171         /* hane pattern - non-cutting hane */
 172         "XO."
 173         "..."
 174         "?.?",
 175         /* hane pattern - magari */
 176         "XO?"
 177         "X.."
 178         "x.?",
 179         /* hane pattern - thin hane */
 180         "XOO"
 181         "..."
 182         "?.?" "X",
 183         /* generic pattern - katatsuke or diagonal attachment; similar to magari */
 184         ".O."
 185         "X.."
 186         "...",
 187         /* cut1 pattern (kiri) - unprotected cut */
 188         "XO?"
 189         "O.o"
 190         "?o?",
 191         /* cut1 pattern (kiri) - peeped cut */
 192         "XO?"
 193         "O.X"
 194         "???",
 195         /* cut2 pattern (de) */
 196         "?X?"
 197         "O.O"
 198         "ooo",
 199         /* cut keima (not in Mogo) */
 200         "OX?"
 201         "o.O"
 202         "???", /* o?? has some pathological tsumego cases */
 203         /* side pattern - chase */
 204         "X.?"
 205         "O.?"
 206         "##?",
 207         /* side pattern - weirdness (SUSPICIOUS) */
 208         "?X?"
 209         "X.O"
 210         "###",
 211         /* side pattern - sagari (SUSPICIOUS) */
 212         "?XO"
 213         "x.x" /* Mogo has "x.?" */
 214         "###" /* Mogo has "X" */,
 215         /* side pattern - throw-in (SUSPICIOUS) */
 216 #if 0
 217         "?OX"
 218         "o.O"
 219         "?##" "X",
 220 #endif
 221         /* side pattern - cut (SUSPICIOUS) */
 222         "?OX"
 223         "X.O"
 224         "###" /* Mogo has "X" */,
 225 };
 226 #define moggy_patterns_src_n sizeof(moggy_patterns_src) / sizeof(moggy_patterns_src[0])
 227
 228 static inline bool
 229 test_pattern3_here(struct playout_policy *p, struct board *b, struct move *m)
 230 {
 231         struct moggy_policy *pp = p->data;
 232         /* Check if 3x3 pattern is matched by given move... */
 233         if (!pattern3_move_here(&pp->patterns, b, m))
 234                 return false;
 235         /* ...and the move is not obviously stupid. */
 236         if (is_bad_selfatari(b, m->color, m->coord))
 237                 return false;
 238         /* Ladder moves are stupid. */
 239         group_t atari_neighbor = board_get_atari_neighbor(b, m->coord, m->color);
 240         if (atari_neighbor && is_ladder(b, m->coord, atari_neighbor, pp->borderladders, pp->ladders))
 241                 return false;
 242         return true;
 243 }
 244
 245 static void
 246 apply_pattern_here(struct playout_policy *p, struct board *b, coord_t c, enum stone color, struct move_queue *q)
 247 {
 248         struct move m2 = { .coord = c, .color = color };
 249         if (board_is_valid_move(b, &m2) && test_pattern3_here(p, b, &m2))
 250                 mq_add(q, c);
 251 }
 252
 253 /* Check if we match any pattern around given move (with the other color to play). */
 254 static coord_t
 255 apply_pattern(struct playout_policy *p, struct board *b, struct move *m, struct move *mm)
 256 {
 257         struct move_queue q;
 258         q.moves = 0;
 259
 260         /* Suicides do not make any patterns and confuse us. */
 261         if (board_at(b, m->coord) == S_NONE || board_at(b, m->coord) == S_OFFBOARD)
 262                 return pass;
 263
 264         foreach_8neighbor(b, m->coord) {
 265                 apply_pattern_here(p, b, c, stone_other(m->color), &q);
 266         } foreach_8neighbor_end;
 267
 268         if (mm) { /* Second move for pattern searching */
 269                 foreach_8neighbor(b, mm->coord) {
 270                         if (coord_is_8adjecent(m->coord, c, b))
 271                                 continue;
 272                         apply_pattern_here(p, b, c, stone_other(m->color), &q);
 273                 } foreach_8neighbor_end;
 274         }
 275
 276         if (PLDEBUGL(5))
 277                 mq_print(&q, b, "Pattern");
 278
 279         return mq_pick(&q);
 280 }
 281
 282
 283 static bool
 284 can_play_on_lib(struct playout_policy *p, struct board_state *s,
 285                 struct board *b, group_t g, enum stone to_play)
 286 {
 287         if (group_is_known(s, g) && group_trait_is_ready(s, g, to_play, capturable)) {
 288                 /* We have already seen this group. */
 289                 assert(s->groups[g].status == G_ATARI);
 290                 if (group_trait_get(s, g, to_play, capturable))
 291                         return true;
 292                 else
 293                         return false;
 294         }
 295
 296         /* Cache miss. Set up cache entry, default at capturable = false. */
 297         group_trait_ready(s, g, to_play, G_ATARI, capturable);
 298
 299         coord_t capture = board_group_info(b, g).lib[0];
 300         if (PLDEBUGL(6))
 301                 fprintf(stderr, "can capture group %d (%s)?\n",
 302                         g, coord2sstr(capture, b));
 303         /* Does playing on the liberty usefully capture the group? */
 304         if (board_is_valid_play(b, to_play, capture)
 305             && !is_bad_selfatari(b, to_play, capture)) {
 306                 group_trait_set(s, g, to_play, capturable, true);
 307                 return true;
 308         }
 309
 310         return false;
 311 }
 312
 313 /* For given position @c, decide if this is a group that is in danger from
 314  * @capturer and @to_play can do anything about it (play at the last
 315  * liberty to either capture or escape). */
 316 /* Note that @to_play is important; e.g. consider snapback, it's good
 317  * to play at the last liberty by attacker, but not defender. */
 318 static __attribute__((always_inline)) bool
 319 capturable_group(struct playout_policy *p, struct board_state *s,
 320                  struct board *b, enum stone capturer, coord_t c,
 321                  enum stone to_play)
 322 {
 323         group_t g = group_at(b, c);
 324         if (likely(board_at(b, c) != stone_other(capturer)
 325                    || board_group_info(b, g).libs > 1))
 326                 return false;
 327
 328         return can_play_on_lib(p, s, b, g, to_play);
 329 }
 330
 331 /* For given atari group @group owned by @owner, decide if @to_play
 332  * can save it / keep it in danger by dealing with one of the
 333  * neighboring groups. */
 334 static bool
 335 can_countercapture(struct playout_policy *p, struct board_state *s,
 336                    struct board *b, enum stone owner, group_t g,
 337                    enum stone to_play, struct move_queue *q)
 338 {
 339         if (b->clen < 2)
 340                 return false;
 341         if (group_is_known(s, g) && group_trait_is_ready(s, g, to_play, can_countercapture)) {
 342                 /* We have already seen this group. */
 343                 assert(s->groups[g].status == G_ATARI);
 344                 if (group_trait_get(s, g, to_play, can_countercapture)) {
 345                         if (q) { /* Scan for countercapture liberties. */
 346                                 goto scan;
 347                         }
 348                         return true;
 349                 } else {
 350                         return false;
 351                 }
 352         }
 353
 354         /* Cache miss. Set up cache entry, default at can_countercapture = true. */
 355         group_trait_ready(s, g, to_play, G_ATARI, can_countercapture);
 356         group_trait_set(s, g, to_play, can_countercapture, true);
 357
 358 scan:;
 359         unsigned int qmoves_prev = q ? q->moves : 0;
 360
 361         foreach_in_group(b, g) {
 362                 foreach_neighbor(b, c, {
 363                         if (!capturable_group(p, s, b, owner, c, to_play))
 364                                 continue;
 365
 366                         if (!q) {
 367                                 return true;
 368                         }
 369                         mq_add(q, board_group_info(b, group_at(b, c)).lib[0]);
 370                         mq_nodup(q);
 371                 });
 372         } foreach_in_group_end;
 373
 374         bool can = q ? q->moves > qmoves_prev : false;
 375         group_trait_set(s, g, to_play, can_countercapture, can);
 376         return can;
 377 }
 378
 379 #ifdef NO_DOOMED_GROUPS
 380 static bool
 381 can_be_rescued(struct playout_policy *p, struct board_state *s,
 382                struct board *b, group_t group, enum stone color)
 383 {
 384         /* Does playing on the liberty rescue the group? */
 385         if (can_play_on_lib(p, s, b, group, color))
 386                 return true;
 387
 388         /* Then, maybe we can capture one of our neighbors? */
 389         return can_countercapture(p, s, b, color, group, color, NULL);
 390 }
 391 #endif
 392
 393 /* ladder != NULL implies to always enqueue all relevant moves. */
 394 static void
 395 group_atari_check(struct playout_policy *p, struct board *b, group_t group, enum stone to_play,
 396                   struct move_queue *q, coord_t *ladder, struct board_state *s)
 397 {
 398         struct moggy_policy *pp = p->data;
 399         int qmoves_prev = q->moves;
 400
 401         /* We don't use @to_play almost anywhere since any moves here are good
 402          * for both defender and attacker. */
 403
 404         enum stone color = board_at(b, group_base(group));
 405         coord_t lib = board_group_info(b, group).lib[0];
 406
 407         assert(color != S_OFFBOARD && color != S_NONE);
 408         if (PLDEBUGL(5))
 409                 fprintf(stderr, "[%s] atariiiiiiiii %s of color %d\n",
 410                         coord2sstr(group, b), coord2sstr(lib, b), color);
 411         assert(board_at(b, lib) == S_NONE);
 412
 413         /* Do not bother with kos. */
 414         if (group_is_onestone(b, group)
 415             && neighbor_count_at(b, lib, color) + neighbor_count_at(b, lib, S_OFFBOARD) == 4)
 416                 return;
 417
 418         /* Can we capture some neighbor? */
 419         bool ccap = can_countercapture(p, s, b, color, group, to_play, q);
 420         if (ccap && !ladder && pp->alwaysccaprate > fast_random(100))
 421                 return;
 422
 423         /* Do not suicide... */
 424         if (!can_play_on_lib(p, s, b, group, to_play))
 425                 return;
 426 #ifdef NO_DOOMED_GROUPS
 427         /* Do not remove group that cannot be saved by the opponent. */
 428         if (to_play != color && !can_be_rescued(p, s, b, group, color))
 429                 return;
 430 #endif
 431         if (PLDEBUGL(6))
 432                 fprintf(stderr, "...escape route valid\n");
 433
 434         /* ...or play out ladders. */
 435         if (is_ladder(b, lib, group, pp->borderladders, pp->ladders)) {
 436                 /* Sometimes we want to keep the ladder move in the
 437                  * queue in order to discourage it. */
 438                 if (!ladder)
 439                         return;
 440                 else
 441                         *ladder = lib;
 442         }
 443         if (PLDEBUGL(6))
 444                 fprintf(stderr, "...no ladder\n");
 445
 446         if (to_play != color) {
 447                 /* We are the attacker! In that case, throw away the moves
 448                  * that defend our groups, since we can capture the culprit. */
 449                 q->moves = qmoves_prev;
 450         }
 451
 452         mq_add(q, lib);
 453         mq_nodup(q);
 454 }
 455
 456 static coord_t
 457 joseki_check(struct playout_policy *p, struct board *b, enum stone to_play, struct board_state *s)
 458 {
 459         struct move_queue q;
 460         q.moves = 0;
 461
 462         for (int i = 0; i < 4; i++) {
 463                 hash_t h = b->qhash[i] & joseki_hash_mask;
 464                 coord_t *cc = joseki_pats[h].moves[to_play];
 465                 if (!cc) continue;
 466                 fprintf(stderr, "%"PRIhash" %d\n", h, i);
 467                 for (; !is_pass(*cc); cc++) {
 468                         if (coord_quadrant(*cc, b) != i)
 469                                 continue;
 470                         mq_add(&q, *cc);
 471                 }
 472         }
 473
 474         if (q.moves > 0) {
 475                 if (PLDEBUGL(5))
 476                         mq_print(&q, b, "Joseki");
 477                 return mq_pick(&q);
 478         }
 479         return pass;
 480 }
 481
 482 static coord_t
 483 global_atari_check(struct playout_policy *p, struct board *b, enum stone to_play, struct board_state *s)
 484 {
 485         struct move_queue q;
 486         q.moves = 0;
 487
 488         if (b->clen == 0)
 489                 return pass;
 490
 491         int g_base = fast_random(b->clen);
 492         for (int g = g_base; g < b->clen; g++) {
 493                 group_atari_check(p, b, group_at(b, group_base(b->c[g])), to_play, &q, NULL, s);
 494                 if (q.moves > 0) {
 495                         if (PLDEBUGL(5))
 496                                 mq_print(&q, b, "Global atari");
 497                         return mq_pick(&q);
 498                 }
 499         }
 500         for (int g = 0; g < g_base; g++) {
 501                 group_atari_check(p, b, group_at(b, group_base(b->c[g])), to_play, &q, NULL, s);
 502                 if (q.moves > 0) {
 503                         if (PLDEBUGL(5))
 504                                 mq_print(&q, b, "Global atari");
 505                         return mq_pick(&q);
 506                 }
 507         }
 508         return pass;
 509 }
 510
 511 static coord_t
 512 local_atari_check(struct playout_policy *p, struct board *b, struct move *m, struct board_state *s)
 513 {
 514         struct move_queue q;
 515         q.moves = 0;
 516
 517         /* Did the opponent play a self-atari? */
 518         if (board_group_info(b, group_at(b, m->coord)).libs == 1) {
 519                 group_atari_check(p, b, group_at(b, m->coord), stone_other(m->color), &q, NULL, s);
 520         }
 521
 522         foreach_neighbor(b, m->coord, {
 523                 group_t g = group_at(b, c);
 524                 if (!g || board_group_info(b, g).libs != 1)
 525                         continue;
 526                 group_atari_check(p, b, g, stone_other(m->color), &q, NULL, s);
 527         });
 528
 529         if (PLDEBUGL(5))
 530                 mq_print(&q, b, "Local atari");
 531
 532         return mq_pick(&q);
 533 }
 534
 535 static bool
 536 miai_2lib(struct board *b, group_t group, enum stone color)
 537 {
 538         bool can_connect = false, can_pull_out = false;
 539         /* We have miai if we can either connect on both libs,
 540          * or connect on one lib and escape on another. (Just
 541          * having two escape routes can be risky.) We must make
 542          * sure that we don't consider following as miai:
 543          * X X X O
 544          * X . . O
 545          * O O X O - left dot would be pull-out, right dot connect */
 546         foreach_neighbor(b, board_group_info(b, group).lib[0], {
 547                 enum stone cc = board_at(b, c);
 548                 if (cc == S_NONE && cc != board_at(b, board_group_info(b, group).lib[1])) {
 549                         can_pull_out = true;
 550                 } else if (cc != color) {
 551                         continue;
 552                 }
 553
 554                 group_t cg = group_at(b, c);
 555                 if (cg && cg != group && board_group_info(b, cg).libs > 1)
 556                         can_connect = true;
 557         });
 558         foreach_neighbor(b, board_group_info(b, group).lib[1], {
 559                 enum stone cc = board_at(b, c);
 560                 if (c == board_group_info(b, group).lib[0])
 561                         continue;
 562                 if (cc == S_NONE && can_connect) {
 563                         return true;
 564                 } else if (cc != color) {
 565                         continue;
 566                 }
 567
 568                 group_t cg = group_at(b, c);
 569                 if (cg && cg != group && board_group_info(b, cg).libs > 1)
 570                         return (can_connect || can_pull_out);
 571         });
 572         return false;
 573 }
 574
 575 static void
 576 check_group_atari(struct board *b, group_t group, enum stone owner,
 577                   enum stone to_play, struct move_queue *q)
 578 {
 579         for (int i = 0; i < 2; i++) {
 580                 coord_t lib = board_group_info(b, group).lib[i];
 581                 assert(board_at(b, lib) == S_NONE);
 582                 if (!board_is_valid_play(b, to_play, lib))
 583                         continue;
 584
 585                 /* Don't play at the spot if it is extremely short
 586                  * of liberties... */
 587                 /* XXX: This looks harmful, could significantly
 588                  * prefer atari to throwin:
 589                  *
 590                  * XXXOOOOOXX
 591                  * .OO.....OX
 592                  * XXXOOOOOOX */
 593 #if 0
 594                 if (neighbor_count_at(b, lib, stone_other(owner)) + immediate_liberty_count(b, lib) < 2)
 595                         continue;
 596 #endif
 597
 598                 /* If the move is too "lumpy", do not play it:
 599                  *
 600                  * #######
 601                  * ..O.X.X <- always play the left one!
 602                  * OXXXXXX */
 603                 if (neighbor_count_at(b, lib, stone_other(owner)) + neighbor_count_at(b, lib, S_OFFBOARD) == 3)
 604                         continue;
 605
 606 #ifdef NO_DOOMED_GROUPS
 607                 /* If the owner can't play at the spot, we don't want
 608                  * to bother either. */
 609                 if (is_bad_selfatari(b, owner, lib))
 610                         continue;
 611 #endif
 612
 613                 /* Of course we don't want to play bad selfatari
 614                  * ourselves, if we are the attacker... */
 615                 if (
 616 #ifdef NO_DOOMED_GROUPS
 617                     to_play != owner &&
 618 #endif
 619                     is_bad_selfatari(b, to_play, lib))
 620                         continue;
 621
 622                 /* Tasty! Crispy! Good! */
 623                 mq_add(q, lib);
 624                 mq_nodup(q);
 625         }
 626 }
 627
 628 static void
 629 group_2lib_check(struct playout_policy *p, struct board *b, group_t group, enum stone to_play,
 630                  struct move_queue *q, struct board_state *s)
 631 {
 632         enum stone color = board_at(b, group_base(group));
 633         assert(color != S_OFFBOARD && color != S_NONE);
 634
 635         if (PLDEBUGL(5))
 636                 fprintf(stderr, "[%s] 2lib check of color %d\n",
 637                         coord2sstr(group, b), color);
 638
 639         /* Do not try to atari groups that cannot be harmed. */
 640         if (miai_2lib(b, group, color))
 641                 return;
 642
 643         check_group_atari(b, group, color, to_play, q);
 644
 645         /* Can we counter-atari another group, if we are the defender? */
 646         if (to_play != color)
 647                 return;
 648         foreach_in_group(b, group) {
 649                 foreach_neighbor(b, c, {
 650                         if (board_at(b, c) != stone_other(color))
 651                                 continue;
 652                         group_t g2 = group_at(b, c);
 653                         if (board_group_info(b, g2).libs != 2)
 654                                 continue;
 655                         check_group_atari(b, g2, color, to_play, q);
 656                 });
 657         } foreach_in_group_end;
 658 }
 659
 660 static coord_t
 661 local_2lib_check(struct playout_policy *p, struct board *b, struct move *m, struct board_state *s)
 662 {
 663         struct move_queue q;
 664         q.moves = 0;
 665
 666         /* Does the opponent have just two liberties? */
 667         if (board_group_info(b, group_at(b, m->coord)).libs == 2) {
 668                 group_2lib_check(p, b, group_at(b, m->coord), stone_other(m->color), &q, s);
 669 #if 0
 670                 /* We always prefer to take off an enemy chain liberty
 671                  * before pulling out ourselves. */
 672                 /* XXX: We aren't guaranteed to return to that group
 673                  * later. */
 674                 if (q.moves)
 675                         return q.move[fast_random(q.moves)];
 676 #endif
 677         }
 678
 679         /* Then he took a third liberty from neighboring chain? */
 680         foreach_neighbor(b, m->coord, {
 681                 group_t g = group_at(b, c);
 682                 if (!g || board_group_info(b, g).libs != 2)
 683                         continue;
 684                 group_2lib_check(p, b, g, stone_other(m->color), &q, s);
 685         });
 686
 687         if (PLDEBUGL(5))
 688                 mq_print(&q, b, "Local 2lib");
 689
 690         return mq_pick(&q);
 691 }
 692
 693 coord_t
 694 playout_moggy_choose(struct playout_policy *p, struct board *b, enum stone to_play)
 695 {
 696         struct moggy_policy *pp = p->data;
 697         coord_t c;
 698
 699         struct board_state *s = board_state_init(b);
 700
 701         if (PLDEBUGL(5))
 702                 board_print(b, stderr);
 703
 704         /* Ko fight check */
 705         if (!is_pass(b->last_ko.coord) && is_pass(b->ko.coord)
 706             && b->moves - b->last_ko_age < pp->koage
 707             && pp->korate > fast_random(100)) {
 708                 if (board_is_valid_play(b, to_play, b->last_ko.coord)
 709                     && !is_bad_selfatari(b, to_play, b->last_ko.coord))
 710                         return b->last_ko.coord;
 711         }
 712
 713         /* Local checks */
 714         if (!is_pass(b->last_move.coord)) {
 715                 /* Local group in atari? */
 716                 if (pp->lcapturerate > fast_random(100)) {
 717                         c = local_atari_check(p, b, &b->last_move, s);
 718                         if (!is_pass(c))
 719                                 return c;
 720                 }
 721
 722                 /* Local group can be PUT in atari? */
 723                 if (pp->atarirate > fast_random(100)) {
 724                         c = local_2lib_check(p, b, &b->last_move, s);
 725                         if (!is_pass(c))
 726                                 return c;
 727                 }
 728
 729                 /* Check for patterns we know */
 730                 if (pp->patternrate > fast_random(100)) {
 731                         c = apply_pattern(p, b, &b->last_move,
 732                                           pp->pattern2 && b->last_move2.coord >= 0 ? &b->last_move2 : NULL);
 733                         if (!is_pass(c))
 734                                 return c;
 735                 }
 736         }
 737
 738         /* Global checks */
 739
 740         /* Any groups in atari? */
 741         if (pp->capturerate > fast_random(100)) {
 742                 c = global_atari_check(p, b, to_play, s);
 743                 if (!is_pass(c))
 744                         return c;
 745         }
 746
 747         /* Joseki moves? */
 748         if (pp->josekirate > fast_random(100)) {
 749                 c = joseki_check(p, b, to_play, s);
 750                 if (!is_pass(c))
 751                         return c;
 752         }
 753
 754         /* Fill board */
 755         unsigned int fbtries = b->flen / 8;
 756         for (unsigned int i = 0; i < (fbtries < pp->fillboardtries ? fbtries : pp->fillboardtries); i++) {
 757                 coord_t coord = b->f[fast_random(b->flen)];
 758                 if (immediate_liberty_count(b, coord) != 4)
 759                         continue;
 760                 foreach_diag_neighbor(b, coord) {
 761                         if (board_at(b, c) != S_NONE)
 762                                 goto next_try;
 763                 } foreach_diag_neighbor_end;
 764                 return coord;
 765 next_try:;
 766         }
 767
 768         return pass;
 769 }
 770
 771
 772 static coord_t
 773 selfatari_cousin(struct board *b, enum stone color, coord_t coord)
 774 {
 775         group_t groups[4]; int groups_n = 0;
 776         foreach_neighbor(b, coord, {
 777                 enum stone s = board_at(b, c);
 778                 if (s != color) continue;
 779                 group_t g = group_at(b, c);
 780                 if (board_group_info(b, g).libs == 2)
 781                         groups[groups_n++] = g;
 782         });
 783
 784         if (!groups_n)
 785                 return pass;
 786         group_t group = groups[fast_random(groups_n)];
 787
 788         coord_t lib2 = board_group_other_lib(b, group, coord);
 789         if (is_bad_selfatari(b, color, lib2))
 790                 return pass;
 791         return lib2;
 792 }
 793
 794 static int
 795 assess_local_bonus(struct playout_policy *p, struct board *board, coord_t a, coord_t b, int games)
 796 {
 797         struct moggy_policy *pp = p->data;
 798         if (!pp->assess_local)
 799                 return games;
 800
 801         int dx = abs(coord_x(a, board) - coord_x(b, board));
 802         int dy = abs(coord_y(a, board) - coord_y(b, board));
 803         /* adjecent move, directly or diagonally? */
 804         if (dx + dy <= 1 + (dx && dy))
 805                 return games;
 806         else
 807                 return games / 2;
 808 }
 809
 810 void
 811 playout_moggy_assess_group(struct playout_policy *p, struct prior_map *map, group_t g, int games,
 812                            struct board_state *s)
 813 {
 814         struct moggy_policy *pp = p->data;
 815         struct board *b = map->b;
 816         struct move_queue q; q.moves = 0;
 817
 818         if (board_group_info(b, g).libs > 2)
 819                 return;
 820
 821         if (PLDEBUGL(5)) {
 822                 fprintf(stderr, "ASSESS of group %s:\n", coord2sstr(g, b));
 823                 board_print(b, stderr);
 824         }
 825
 826         if (board_group_info(b, g).libs == 2) {
 827                 if (!pp->atarirate)
 828                         return;
 829                 group_2lib_check(p, b, g, map->to_play, &q, s);
 830                 while (q.moves--) {
 831                         coord_t coord = q.move[q.moves];
 832                         if (PLDEBUGL(5))
 833                                 fprintf(stderr, "1.0: 2lib %s\n", coord2sstr(coord, b));
 834                         int assess = assess_local_bonus(p, b, b->last_move.coord, coord, games) / 2;
 835                         add_prior_value(map, coord, 1, assess);
 836                 }
 837                 return;
 838         }
 839
 840         /* This group, sir, is in atari! */
 841
 842         if (!pp->capturerate && !pp->lcapturerate && !pp->ladderassess)
 843                 return;
 844
 845         coord_t ladder = pass;
 846         group_atari_check(p, b, g, map->to_play, &q, &ladder, s);
 847         while (q.moves--) {
 848                 coord_t coord = q.move[q.moves];
 849
 850                 /* _Never_ play here if this move plays out
 851                  * a caught ladder. */
 852                 if (coord == ladder && !board_playing_ko_threat(b)) {
 853                         /* Note that the opposite is not guarded against;
 854                          * we do not advise against capturing a laddered
 855                          * group (but we don't encourage it either). Such
 856                          * a move can simplify tactical situations if we
 857                          * can afford it. */
 858                         if (!pp->ladderassess || map->to_play != board_at(b, g))
 859                                 continue;
 860                         /* FIXME: We give the malus even if this move
 861                          * captures another group. */
 862                         if (PLDEBUGL(5))
 863                                 fprintf(stderr, "0.0: ladder %s\n", coord2sstr(coord, b));
 864                         add_prior_value(map, coord, 0, games);
 865                         continue;
 866                 }
 867
 868                 if (!pp->capturerate && !pp->lcapturerate)
 869                         continue;
 870
 871                 if (PLDEBUGL(5))
 872                         fprintf(stderr, "1.0: atari %s\n", coord2sstr(coord, b));
 873                 int assess = assess_local_bonus(p, b, b->last_move.coord, coord, games) * 2;
 874                 add_prior_value(map, coord, 1, assess);
 875         }
 876 }
 877
 878 void
 879 playout_moggy_assess_one(struct playout_policy *p, struct prior_map *map, coord_t coord, int games)
 880 {
 881         struct moggy_policy *pp = p->data;
 882         struct board *b = map->b;
 883
 884         if (PLDEBUGL(5)) {
 885                 fprintf(stderr, "ASSESS of move %s:\n", coord2sstr(coord, b));
 886                 board_print(b, stderr);
 887         }
 888
 889         /* Is this move a self-atari? */
 890         if (pp->selfatarirate) {
 891                 if (!board_playing_ko_threat(b) && is_bad_selfatari(b, map->to_play, coord)) {
 892                         if (PLDEBUGL(5))
 893                                 fprintf(stderr, "0.0: self-atari\n");
 894                         add_prior_value(map, coord, 0, games);
 895                         if (!pp->selfatari_other)
 896                                 return;
 897                         /* If we can play on the other liberty of the
 898                          * endangered group, do! */
 899                         coord = selfatari_cousin(b, map->to_play, coord);
 900                         if (is_pass(coord))
 901                                 return;
 902                         if (PLDEBUGL(5))
 903                                 fprintf(stderr, "1.0: self-atari redirect %s\n", coord2sstr(coord, b));
 904                         add_prior_value(map, coord, 1.0, games);
 905                         return;
 906                 }
 907         }
 908
 909         /* Pattern check */
 910         if (pp->patternrate) {
 911                 struct move m = { .color = map->to_play, .coord = coord };
 912                 if (test_pattern3_here(p, b, &m)) {
 913                         if (PLDEBUGL(5))
 914                                 fprintf(stderr, "1.0: pattern\n");
 915                         int assess = assess_local_bonus(p, b, b->last_move.coord, coord, games);
 916                         add_prior_value(map, coord, 1, assess);
 917                 }
 918         }
 919
 920         return;
 921 }
 922
 923 void
 924 playout_moggy_assess(struct playout_policy *p, struct prior_map *map, int games)
 925 {
 926         struct moggy_policy *pp = p->data;
 927
 928         struct board_state *s = board_state_init(map->b);
 929
 930         /* First, go through all endangered groups. */
 931         if (pp->lcapturerate || pp->capturerate || pp->atarirate || pp->ladderassess)
 932                 for (group_t g = 1; g < board_size2(map->b); g++)
 933                         if (group_at(map->b, g) == g)
 934                                 playout_moggy_assess_group(p, map, g, games, s);
 935
 936         /* Then, assess individual moves. */
 937         if (!pp->patternrate && !pp->selfatarirate)
 938                 return;
 939         foreach_free_point(map->b) {
 940                 if (map->consider[c])
 941                         playout_moggy_assess_one(p, map, c, games);
 942         } foreach_free_point_end;
 943 }
 944
 945 bool
 946 playout_moggy_permit(struct playout_policy *p, struct board *b, struct move *m)
 947 {
 948         struct moggy_policy *pp = p->data;
 949
 950         /* The idea is simple for now - never allow self-atari moves.
 951          * They suck in general, but this also permits us to actually
 952          * handle seki in the playout stage. */
 953
 954         if (fast_random(100) >= pp->selfatarirate) {
 955                 if (PLDEBUGL(5))
 956                         fprintf(stderr, "skipping sar test\n");
 957                 return true;
 958         }
 959         bool selfatari = is_bad_selfatari(b, m->color, m->coord);
 960         if (selfatari) {
 961                 if (PLDEBUGL(5))
 962                         fprintf(stderr, "__ Prohibiting self-atari %s %s\n",
 963                                 stone2str(m->color), coord2sstr(m->coord, b));
 964                 if (pp->selfatari_other) {
 965                         /* Ok, try the other liberty of the atari'd group. */
 966                         coord_t c = selfatari_cousin(b, m->color, m->coord);
 967                         if (is_pass(c)) return false;
 968                         if (PLDEBUGL(5))
 969                                 fprintf(stderr, "___ Redirecting to other lib %s\n",
 970                                         coord2sstr(c, b));
 971                         m->coord = c;
 972                         return true;
 973                 }
 974                 return false;
 975         }
 976         return true;
 977 }
 978
 979
 980 struct playout_policy *
 981 playout_moggy_init(char *arg, struct board *b)
 982 {
 983         struct playout_policy *p = calloc2(1, sizeof(*p));
 984         struct moggy_policy *pp = calloc2(1, sizeof(*pp));
 985         p->data = pp;
 986         p->choose = playout_moggy_choose;
 987         p->assess = playout_moggy_assess;
 988         p->permit = playout_moggy_permit;
 989
 990         int rate = 90;
 991
 992         pp->lcapturerate = pp->atarirate = pp->capturerate = pp->patternrate = pp->selfatarirate
 993                         = -1U;
 994         pp->korate = 0; pp->koage = 4;
 995         pp->alwaysccaprate = 0;
 996         pp->josekirate = 0;
 997         pp->ladders = pp->borderladders = true;
 998         pp->ladderassess = true;
 999
1000         if (arg) {
1001                 char *optspec, *next = arg;
1002                 while (*next) {
1003                         optspec = next;
1004                         next += strcspn(next, ":");
1005                         if (*next) { *next++ = 0; } else { *next = 0; }
1006
1007                         char *optname = optspec;
1008                         char *optval = strchr(optspec, '=');
1009                         if (optval) *optval++ = 0;
1010
1011                         if (!strcasecmp(optname, "lcapturerate") && optval) {
1012                                 pp->lcapturerate = atoi(optval);
1013                         } else if (!strcasecmp(optname, "atarirate") && optval) {
1014                                 pp->atarirate = atoi(optval);
1015                         } else if (!strcasecmp(optname, "capturerate") && optval) {
1016                                 pp->capturerate = atoi(optval);
1017                         } else if (!strcasecmp(optname, "patternrate") && optval) {
1018                                 pp->patternrate = atoi(optval);
1019                         } else if (!strcasecmp(optname, "selfatarirate") && optval) {
1020                                 pp->selfatarirate = atoi(optval);
1021                         } else if (!strcasecmp(optname, "korate") && optval) {
1022                                 pp->korate = atoi(optval);
1023                         } else if (!strcasecmp(optname, "josekirate") && optval) {
1024                                 pp->josekirate = atoi(optval);
1025                         } else if (!strcasecmp(optname, "alwaysccaprate") && optval) {
1026                                 pp->alwaysccaprate = atoi(optval);
1027                         } else if (!strcasecmp(optname, "rate") && optval) {
1028                                 rate = atoi(optval);
1029                         } else if (!strcasecmp(optname, "fillboardtries")) {
1030                                 pp->fillboardtries = atoi(optval);
1031                         } else if (!strcasecmp(optname, "koage") && optval) {
1032                                 pp->koage = atoi(optval);
1033                         } else if (!strcasecmp(optname, "ladders")) {
1034                                 pp->ladders = optval && *optval == '0' ? false : true;
1035                         } else if (!strcasecmp(optname, "borderladders")) {
1036                                 pp->borderladders = optval && *optval == '0' ? false : true;
1037                         } else if (!strcasecmp(optname, "ladderassess")) {
1038                                 pp->ladderassess = optval && *optval == '0' ? false : true;
1039                         } else if (!strcasecmp(optname, "assess_local")) {
1040                                 pp->assess_local = optval && *optval == '0' ? false : true;
1041                         } else if (!strcasecmp(optname, "pattern2")) {
1042                                 pp->pattern2 = optval && *optval == '0' ? false : true;
1043                         } else if (!strcasecmp(optname, "selfatari_other")) {
1044                                 pp->selfatari_other = optval && *optval == '0' ? false : true;
1045                         } else {
1046                                 fprintf(stderr, "playout-moggy: Invalid policy argument %s or missing value\n", optname);
1047                                 exit(1);
1048                         }
1049                 }
1050         }
1051         if (pp->lcapturerate == -1U) pp->lcapturerate = rate;
1052         if (pp->atarirate == -1U) pp->atarirate = rate;
1053         if (pp->capturerate == -1U) pp->capturerate = rate;
1054         if (pp->patternrate == -1U) pp->patternrate = rate;
1055         if (pp->selfatarirate == -1U) pp->selfatarirate = rate;
1056         if (pp->korate == -1U) pp->korate = rate;
1057         if (pp->josekirate == -1U) pp->josekirate = rate;
1058         if (pp->alwaysccaprate == -1U) pp->alwaysccaprate = rate;
1059
1060         pattern3s_init(&pp->patterns, moggy_patterns_src, moggy_patterns_src_n);
1061
1062         return p;
1063 }