/* -*-mode:c; c-style:k&r; c-basic-offset:4; -*- */


/****************************************************************************
 *                                                                          *
 *                      Velena Source Code V1.0                             *
 *                   Written by Giuliano Bertoletti                         *
 *       Based on the knowledged approach of Louis Victor Allis             *
 *   Copyright (C) 1996-97 by Giuliano Bertoletti & GBE 32241 Software PR   *
 *                                                                          *
 ****************************************************************************

 Portable engine version.
 read the README file for further informations.

 ============================================================================

 Changes have been made to this code for inclusion with Gnect. It is
 released under the GNU General Public License with Giuliano's approval.
 The original and complete Velena Engine source code can be found at:

 http://www.ce.unipr.it/~gbe/velena.html

*/


#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#include <gnome.h>

#include "connect4.h"
#include "pnsearch.h"
#include "proto.h"

#include "config.h"
#include "main.h"


#define BLKSIZE 16384   /* Buffer size for I/O */
#define PLAYER1 0
#define PLAYER2 1



struct board *brd;




void fatal_error(char *str)
{
	g_printerr ("velena: %s\n", str);
	exit(1);
}



int my_random(unsigned short maxval)
{
	/* range: 0..maxval-1 */
	return( get_random_int(maxval) - 1 );
}



long fileln(FILE *f)
{
	long int save_pos, file_size;

	save_pos = ftell(f);
	if(save_pos == -1)
		return -1L;
	fseek(f,0L,SEEK_END);
	file_size = ftell(f);
	fseek(f, save_pos,SEEK_SET);

	return file_size;
}



static short check_solution_groups(struct board *board)
{
	short x, y, z, q, c, answer = YES;

	for (y = 0; y < BOARDY && answer; y++) {
		for (x = 0; x < BOARDX && answer; x++) {
			for (z = 0; z < board->solvable_groups->sqpnt[ELM(x,y)] && answer; z++) {
				answer = NO;
				c = board->solvable_groups->square[ELM(x, y)][z];
				for (q = 0; q < TILES; q++) {
					if (*board->groups[c][q] == ELM(x, y)) {
						answer = YES;
					}
				}
			}
		}
	}
	return(answer);
}


/* Initialize the program data structures, it reads and builds (if needed)
 * the opening book.
 */

static void init_prg(struct board *board)
{
	long size,len;
	FILE *h1;
	short x;
	char *tmp = g_strconcat ( "gnect/", WHITE_BOOK, NULL);
	char *bookdata = gnome_program_locate_file (NULL, GNOME_FILE_DOMAIN_APP_DATADIR, tmp, FALSE, NULL);
	g_free(tmp);

	if (!g_file_test(bookdata, G_FILE_TEST_EXISTS)) {
		g_printerr ("velena: required file not found (%s)\n", bookdata);
		exit(1);
	}

	brd = board;

	board->wins[PLAYER1] = 0;
	board->wins[PLAYER2] = 0;
	board->draws         = 0;
	board->lastguess     = 0;
	board->bestguess     = MAXMEN;
	board->lastwin       = EMPTY;

	board->white_lev = 0;   /* Human */
	board->black_lev = 3;   /* Computer-Strong */
	board->videotype = CHARS;
	board->enablegr  = NO;
	board->autotest  = NO;

	for(x = 0; x < 3; x++) {
		board->rule[x]=0L;
	}

	board->oracle_guesses = 0;


	h1=fopen(bookdata, "rb");
	if(!h1) {
		g_printerr("velena: could not open required file (%s)\n", bookdata);
		exit(1);
	}

	size = fileln(h1);
	if (size%14 != 0) {
		fatal_error("White opening book is corrupted");
	}

	board->wbposit = size/14;

	board->white_book = (unsigned char *)malloc(size);
	if(!board->white_book) {
		fatal_error("Not enough memory to allocate opening book");
	}

	len = 0;               /* We read all the position from disk */
	while(size > 0) {      /* each position takes 14 bytes of storage */
		fread(&board->white_book[len], 1, 14, h1);
		len += 14;
		size -= 14;
	}

	fclose(h1);

	board->bbposit=0;
}



void initboard(struct board *board)
{
	short x, y, i, j, p;

	/* randomize(); */ /* see main.c, game_init() */

	for (i = 0; i < 10; i++) {
		board->instances[i] = 0L;
	}

	/* Groups initializations */

	/* Step one. Horizontal lines. */

	i = 0;
	for (y = 0; y < BOARDY; y++) {
		for (x = 0; x < BOARDX-3; x++) {
			board->groups[i][0] = &board->square[ELM(x+0,y)];
			board->groups[i][1] = &board->square[ELM(x+1,y)];
			board->groups[i][2] = &board->square[ELM(x+2,y)];
			board->groups[i][3] = &board->square[ELM(x+3,y)];

			board->xplace[i][0] = x;
			board->xplace[i][1] = x+1;
			board->xplace[i][2] = x+2;
			board->xplace[i][3] = x+3;

			board->yplace[i][0] = y;
			board->yplace[i][1] = y;
			board->yplace[i][2] = y;
			board->yplace[i][3] = y;

			i++;
		}
	}

	/* Step two. Vertical lines */

	for (y = 0; y < BOARDY-3; y++) {
		for (x = 0; x < BOARDX; x++) {
			board->groups[i][0] = &board->square[ELM(x,y+0)];
			board->groups[i][1] = &board->square[ELM(x,y+1)];
			board->groups[i][2] = &board->square[ELM(x,y+2)];
			board->groups[i][3] = &board->square[ELM(x,y+3)];

			board->xplace[i][0] = x;
			board->xplace[i][1] = x;
			board->xplace[i][2] = x;
			board->xplace[i][3] = x;

			board->yplace[i][0] = y+0;
			board->yplace[i][1] = y+1;
			board->yplace[i][2] = y+2;
			board->yplace[i][3] = y+3;

			i++;
		}
	}

	/* Step three. Diagonal (north east) lines */

	for (y = 0; y < BOARDY-3; y++) {
		for (x = 0; x < BOARDX-3; x++) {
			board->groups[i][0] = &board->square[ELM(x+0,y+0)];
			board->groups[i][1] = &board->square[ELM(x+1,y+1)];
			board->groups[i][2] = &board->square[ELM(x+2,y+2)];
			board->groups[i][3] = &board->square[ELM(x+3,y+3)];

			board->xplace[i][0] = x+0;
			board->xplace[i][1] = x+1;
			board->xplace[i][2] = x+2;
			board->xplace[i][3] = x+3;

			board->yplace[i][0] = y+0;
			board->yplace[i][1] = y+1;
			board->yplace[i][2] = y+2;
			board->yplace[i][3] = y+3;

			i++;
		}
	}

	/* Step four. Diagonal (south east) lines */

	for (y = 3; y < BOARDY; y++) {
		for (x = 0; x < BOARDX-3; x++) {
			board->groups[i][0] = &board->square[ELM(x+0,y-0)];
			board->groups[i][1] = &board->square[ELM(x+1,y-1)];
			board->groups[i][2] = &board->square[ELM(x+2,y-2)];
			board->groups[i][3] = &board->square[ELM(x+3,y-3)];

			board->xplace[i][0] = x+0;
			board->xplace[i][1] = x+1;
			board->xplace[i][2] = x+2;
			board->xplace[i][3] = x+3;

			board->yplace[i][0] = y-0;
			board->yplace[i][1] = y-1;
			board->yplace[i][2] = y-2;
			board->yplace[i][3] = y-3;

			i++;
		}
	}

	if (i != GROUPS) {
		fatal_error("Implementation error!");
	}

	for (x = 0; x < 64; x++) {
		board->solvable_groups->sqpnt[x] = 0;
		for (y = 0; y < 16; y++) {
			board->solvable_groups->square[x][y] = -1;
		}
	}

	for (x = 0; x < BOARDX; x++) {
		for (y = 0; y < BOARDY; y++) {
			board->square[ELM(x,y)] = ELM(x, y);
		}
	}

	for (i = 0; i < GROUPS; i++) {
		for (j = 0; j < TILES; j++) {
			p = *board->groups[i][j];
			board->solvable_groups->square[p][board->solvable_groups->sqpnt[p]++] = i;
		}
	}

	if (!check_solution_groups(board)) {
		fatal_error("Implementation error!");
	}

	/* Here we set all out squares to a default value to detect problems */

	for (i = 0; i < 8; i++) {
		board->square[ELM(7,i)] = FULL;
		board->square[ELM(i,6)] = board->square[ELM(i,7)] = FULL;
	}

	board->stack[7] = FULL;

	for (y = 0; y < BOARDY; y++) {
		for (x = 0; x < BOARDX; x++) {
			board->square[ELM(x,y)] = EMPTY;
		}
	}

	for (x = 0; x < BOARDX; x++) {
		board->stack[x] = 0;
	}

	board->turn = WHITE;
	board->filled = 0;
	board->cpu = 0x01;

	return;
}


#if 0
static void initTitle(void)
{
	g_print("\nVelena Engine %s; revision %s\n", SEARCH_ENGINE_VERSION, __DATE__);
	g_print("\nAI engine written by Giuliano Bertoletti\n");
	g_print("Based on the knowledged approach of Victor Allis\n");
	g_print("Copyright (C) 1996-97 Giuliano Bertoletti ");
	g_print("and GBE 32241 Software PR.\n");
	g_print("All rights reserved.\n\n");
}
#endif


struct board *veleng_init(void)
{
	short x;
	struct board *board;

	/* Here we initialize our environment and the call
	 * command_line_input in file cmdline.c to process data from the
	 * outside world.
	 */


	/* initTitle(); Moved this to the About dialog */
	
	fight(NO);

	brd = NULL;
	board = (struct board *)malloc(sizeof(struct board));
	if(!board) {
		fatal_error("Cannot allocate memory!");
	}

	board->solvable_groups = (struct solvable_groups *)malloc(sizeof(struct solvable_groups));
	if(!board->solvable_groups) {
		fatal_error("Cannot allocate memory!");
	}

	board->debug = 0;

	init_prg(board);       /* Initialize data structures */

	for (x = 0; x < ALLOC_SOLUTIONS; x++) {
		board->solution[x] = (struct solution *)malloc(sizeof(struct solution));
		if (!board->solution[x]) {
			fatal_error("Not enough memory for solutions");
		}
	}

	board->usegraphics = NO;

	return(board);
}



void veleng_free(struct board *board)
{
	int x;

	if (board != NULL) {

		for (x = 0; x < ALLOC_SOLUTIONS; x++) {
			if(board->solution[x] != NULL) {
				free(board->solution[x]);
			}
		}

		free(board->solvable_groups);
		free(board);

	}

}