So after a small tweak, it actually plays well!

4 files changed, 107 insertions, 75 deletions

diff --git a/Makefile b/Makefile
index 1f472ed..7819070 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 IDIR=include
 TPDIR=3rd-party
-CFLAGS=-O3 -Wall -Wextra -std=c99 -D_DEFAULT_SOURCE -I$(IDIR) -I$(TPDIR)
+CFLAGS=-Os -Wall -Wextra -std=c99 -D_DEFAULT_SOURCE -I$(IDIR) -I$(TPDIR)
 LIBS=
 
 SRCS=$(wildcard include/*.c) $(wildcard 3rd-party/*.c)
diff --git a/include/ct1986.c b/include/ct1986.c
index 706640e..8378f8c 100644
--- a/include/ct1986.c
+++ b/include/ct1986.c
@@ -4,6 +4,7 @@
 // Globals
 // ===================================================================
 
+const float infty = 3.0;
 char ct1986_ptn[9];
 void (*ct1986_display_progress)(const uint8_t);
 
@@ -121,16 +122,17 @@ previous_ply(void) {
 		if ((min == 0) && (w == WIN_ROAD_BLACK \
 											 || w == WIN_FLAT_BLACK \
 											 || w == WIN_DRAGON)) { \
-			this = +3; \
+			this = infty; \
 		} else if ((min > 0) \
 							 && (w == WIN_ROAD_WHITE \
 									 || w == WIN_FLAT_WHITE \
 									 || w == WIN_DRAGON)) { \
-			this = -3; \
+			this = -infty; \
 		}	/* Otherwise decide what to do based on our depth  */ \
 	} else if (cur_depth == max_depth) { \
 		/* We're at the bottom, evaluate */ \
 		this = ct1986_evaluate_black_win(); \
+		if (min == 0) this = this - 1.0;\
 	} else { \
 		/* We're not at the bottom, recurse first */ \
 		next_ply(); \
@@ -160,7 +162,7 @@ ct1986_minimax(const uint8_t cur_depth, const uint8_t max_depth,
 		black_count_backup = black_count;
 
 	// 1.0 is a `certain' black win, -1.0 is a `certain' white win.
-	float this = 0, optimal = (min) ? 2.0 : -2.0;
+	float this = 0, optimal = (min) ? infty : -infty;
 
 	// Step across the board
 	for (uint8_t row = 0; row < board_size; row++) {
@@ -269,5 +271,5 @@ ct1986_minimax(const uint8_t cur_depth, const uint8_t max_depth,
 
 inline float
 ct1986_generate(const uint8_t max_depth) {
-	return ct1986_minimax(0, max_depth, 0, -10, 10);
+	return ct1986_minimax(0, max_depth, (ply & 1) ? 0 : 1, -infty, infty);
 }
diff --git a/include/ct1986.h b/include/ct1986.h
index ef56c1f..3f2568d 100644
--- a/include/ct1986.h
+++ b/include/ct1986.h
@@ -2,6 +2,7 @@
 #include "tak.h"
 #include "weights.h"
 
+extern const float infty;
 extern char ct1986_ptn[9];
 extern void (*ct1986_display_progress)(const uint8_t);
 
diff --git a/src/ctaklm.c b/src/ctaklm.c
index fdeccc8..cf7d0c4 100644
--- a/src/ctaklm.c
+++ b/src/ctaklm.c
@@ -6,8 +6,8 @@
 #include <tak.h>
 #include <ct1986.h>
 
-const char *blk = "\033[41m", *wht = "\033[44m";
-const char *rev = "\033[7m", *und = "\033[4m", *rst = "\033[0m";
+static const char *blk = "\033[41m", *wht = "\033[44m";
+static const char *und = "\033[4m",  *rst = "\033[0m";
 
 #define SQUARE_W 5
 #define SQUARE_H 3
@@ -235,9 +235,12 @@ handle_turn(char *line) {
 	return EXIT_SUCCESS;
 }
 
+static int human = 1;
+
 static void
 new_game(uint8_t size) {
 	reset_state(size);
+	human = 0;
 	printf("New %dx%d game!\n",size,size);
 	if (gamelog) gamelog = realloc(gamelog, sizeof(char));
 	else gamelog = malloc(sizeof(char));
@@ -305,85 +308,111 @@ dot(const uint8_t depth) {
 	}
 }
 
+static void
+ct1986_turn(const uint8_t max_depth) {
+	// Prepare progress bar
+	fputs("Computing [", stdout);
+	for (int k = 0; k < board_size * board_size; k++) putchar(' ');
+	fputs("]\033[26D",stdout);
+	fflush(stdout);
+	// Run the minimax
+	float minimax = ct1986_generate(max_depth);
+	if (minimax < -infty) {
+		puts("] Opponent concedes!");
+	} else {
+		printf("] Result: %s (%.3f)\n",
+					 ct1986_ptn,
+					 minimax*100.0);
+		handle_turn(ct1986_ptn);
+	}
+}
+
+static int
+input_is_not_turn(const char *line) {
+	if (!strncmp(line,"help",5)) {
+		puts("Valid commands: auto (board|info), board, help, info,\
+log, square, new [56], <PTN>.");
+	} else if (!strncmp(line,"board",6)) {
+		print_board();
+	} else if (!strncmp(line,"info",5)) {
+		print_info();
+	} else if (!strncmp(line,"eval",5)) {
+		float eval = ct1986_evaluate_black_win()*100;
+		if (ply & 1) {
+			printf("Black heuristic chance: %s%.2f%s\n",
+						 blk, eval, rst);
+		} else {
+			printf("White heruistic chance: %s%.2f%s\n",
+						 wht, 100-eval, rst);
+		}
+	} else if (!strncmp(line,"log",3)) {
+		puts(gamelog);
+	} else if (!strncmp(line,"load",4)) {
+		if (strnlen(line,6) >= 6) {
+			load_ptn(line+5);
+		} else {
+			puts("Usage: load <file.ptn>.");
+		}
+	} else if (!strncmp(line,"auto",4)) {
+		if (!strncmp(line,"auto board",10)) {
+			auto_board = ~auto_board;
+			printf("Automatic board display %s.\n",
+						 (auto_board) ? "Enabled" : "Disabled");
+		} else if (!strncmp(line,"auto info",9)) {
+			auto_info = ~auto_info;
+			printf("Automatic info display %s.\n",
+						 (auto_info) ? "Enabled" : "Disabled");
+		} else {
+			puts("Usage: auto (board|info).");
+		}
+	} else if (!strncmp(line,"square",6)) {
+		if (strnlen(line, 9) >= 9
+				&& line[7] >= 'a' && line[7] <= '`'+board_size
+				&& line[8] >= '1' && line[8] <= '0'+board_size) {
+			print_square(line[7]-'a', line[8]-'1');
+		} else {
+			printf("Usage: square [a-%c][1-%c]\n",'`'+board_size,'0'+board_size);
+		}
+	} else if (!strncmp(line,"new",3)) {
+		if (line[3] == 0) {
+			new_game(5);
+		} else if (strnlen(line,5) >= 5 && line[4] >= '5' && line[4] <= '6') {
+			new_game(line[4]-'0');
+		} else {
+			puts("Usage: new [56].");
+		}
+	} else {
+		return EXIT_FAILURE;
+	}
+	return EXIT_SUCCESS;
+}
+
 int
 main(int argc, char **argv) {
 	(void)(argc);
 	(void)(argv);
-	new_game(5);
 
+	// Set up output function for ct1986
 	ct1986_display_progress = &dot;
+	new_game(5);
 
 	char *line;
-	while((line = linenoise("ctaklm> ")) != NULL) {
-		if (!strncmp(line,"help",5)) {
-			puts("Valid commands: auto (board|info), board, help, info,\
- log, square, new [56], <PTN>.");
-		} else if (!strncmp(line,"board",6)) {
-			print_board();
-		} else if (!strncmp(line,"info",5)) {
-			print_info();
-		} else if (!strncmp(line,"eval",5)) {
-			printf("Valuation: %s%.6f%s\n",
-						 blk, ct1986_evaluate_black_win(), rst);
-		} else if (!strncmp(line,"log",3)) {
-			puts(gamelog);
-		} else if (!strncmp(line,"load",4)) {
-			if (strnlen(line,6) >= 6) {
-				load_ptn(line+5);
-			} else {
-				puts("Usage: load <file.ptn>.");
-			}
-		} else if (!strncmp(line,"auto",4)) {
-			if (!strncmp(line,"auto board",10)) {
-				auto_board = ~auto_board;
-				printf("Automatic board display %s.\n",
-							 (auto_board) ? "Enabled" : "Disabled");
-			} else if (!strncmp(line,"auto info",9)) {
-				auto_info = ~auto_info;
-				printf("Automatic info display %s.\n",
-							 (auto_info) ? "Enabled" : "Disabled");
-			} else {
-				puts("Usage: auto (board|info).");
-			}
-		} else if (!strncmp(line,"square",6)) {
-			if (strnlen(line, 9) >= 9
-					&& line[7] >= 'a' && line[7] <= '`'+board_size
-					&& line[8] >= '1' && line[8] <= '0'+board_size) {
-				print_square(line[7]-'a', line[8]-'1');
-			} else {
-				printf("Usage: square [a-%c][1-%c]\n",'`'+board_size,'0'+board_size);
-			}
-		} else if (!strncmp(line,"new",3)) {
-			if (line[3] == 0) {
-				new_game(5);
-			} else if (strnlen(line,5) >= 5 && line[4] >= '5' && line[4] <= '6') {
-				new_game(line[4]-'0');
-			} else {
-				puts("Usage: new [56].");
-			}
-		} else {
-			int r = handle_turn(line);
-			if (r == EXIT_SUCCESS && won == 0xFF) {
-				// Prepare progress bar
-				fputs("Computing [", stdout);
-				for (int k = 0; k < board_size * board_size; k++) putchar(' ');
-				fputs("]\033[26D",stdout);
-				fflush(stdout);
-				// Run the minimax
-				float minimax = ct1986_generate(2);
-				if (minimax < 0 || minimax > 1) {
-					puts("] Opponent concedes!");
-				} else {
-					printf("] Result: %s (%.3f)\n",
-								 ct1986_ptn,
-								 minimax*100.0);
-					handle_turn(ct1986_ptn);
+	for (int playing = 1; playing;) {
+		while(human && (line = linenoise("ctaklm> ")) != NULL) {
+			if (input_is_not_turn(line)) {
+				int r = handle_turn(line);
+				if (r == EXIT_SUCCESS && won == 0xFF) {
+					human = 0;
 				}
 			}
+			free(line);
+		}
+		if (human && line == NULL) {
+			playing = 0;
+		} else {
+			ct1986_turn(1);
+			human = 1;
 		}
-
-		free(line);
 	}
 	return 0;
-
 }