simple implementation of uci protocol (thomasahle#43)

* simple implementation of uci protocol

* checkout sunfish.py to previous commit

* simplify uci.py, import Unbuffered from xboard.py

Author: ryanhs

uci.py

@@ -0,0 +1,121 @@
+#!/usr/bin/env pypy -u
+# -*- coding: utf-8 -*-
+
+from __future__ import print_function
+from __future__ import division
+import importlib
+import re
+import sys
+import time
+
+import tools
+import sunfish
+
+from tools import WHITE, BLACK
+from xboard import Unbuffered, sunfish, input
+sys.stdout = Unbuffered(sys.stdout)
+
+def main():
+    pos = tools.parseFEN(tools.FEN_INITIAL)
+    searcher = sunfish.Searcher()
+    forced = False
+    color = WHITE
+    our_time, opp_time = 1000, 1000 # time in centi-seconds
+    show_thinking = True
+
+    # print name of chess engine
+    print('Sunfish')
+
+    stack = []
+    while True:
+        if stack:
+            smove = stack.pop()
+        else: smove = input()
+
+        if smove == 'quit':
+            break
+
+        elif smove == 'uci':
+            print('uciok')
+
+        elif smove == 'isready':
+            print('readyok')
+
+        elif smove == 'ucinewgame':
+            stack.append('position fen ' + tools.FEN_INITIAL)
+
+        elif smove.startswith('position'):
+            params = smove.split(' ', 2)
+            if params[1] == 'fen':
+                fen = params[2]
+                pos = tools.parseFEN(fen)
+                color = WHITE if fen.split()[1] == 'w' else BLACK
+
+        elif smove.startswith('go'):
+            #  default options
+            depth = 1000
+            movetime = -1
+
+            # parse parameters
+            params = smove.split(' ')
+            if len(params) == 1: continue
+
+            i = 0
+            while i < len(params):
+                param = params[i]
+                if param == 'depth':
+                    i += 1
+                    depth = int(params[i])
+                if param == 'movetime':
+                    i += 1
+                    movetime = int(params[i])
+                i += 1
+
+            forced = False
+
+            moves_remain = 40
+
+            start = time.time()
+            ponder = None
+            for _ in searcher._search(pos):
+                moves = tools.pv(searcher, pos, include_scores=False)
+
+                if show_thinking:
+                    entry = searcher.tp_score.get((pos, searcher.depth, True))
+                    score = int(round((entry.lower + entry.upper)/2))
+                    usedtime = int((time.time() - start) * 1000)
+                    moves_str = moves if len(moves) < 15 else ''
+                    print('info depth {} score {} time {} nodes {} {}'.format(searcher.depth, score, usedtime, searcher.nodes, moves_str))
+
+                if len(moves) > 5:
+                    ponder = moves[1]
+
+                if movetime > 0 and (time.time() - start) * 1000 > movetime:
+                    break
+
+                if searcher.depth >= depth:
+                    break
+
+            entry = searcher.tp_score.get((pos, searcher.depth, True))
+            m, s = searcher.tp_move.get(pos), entry.lower
+            # We only resign once we are mated.. That's never?
+            if s == -sunfish.MATE_UPPER:
+                print('resign')
+            else:
+                moves = moves.split(' ')
+                if len(moves) > 1:
+                    print('bestmove ' + moves[0] + ' ponder ' + moves[1])
+                else:
+                    print('bestmove ' + moves[0])
+
+        elif smove.startswith('time'):
+            our_time = int(smove.split()[1])
+
+        elif smove.startswith('otim'):
+            opp_time = int(smove.split()[1])
+
+        else:
+            pass
+
+if __name__ == '__main__':
+    main()