#include <assert.h>
#include <string.h>
#include "general.h"

/* Variables related to the showing of information by os */
extern float percent_to_show;
extern int depth_to_show;

extern int max_depth;
extern int min_depth_period;
extern int max_depth_period;
extern struct Map * actual_map;

#if 0 /*** THIS IS AN ERROR!!!  The box_will_be_blocked function doesn't work!*/
 Situation:
    
  ->@$ #
      $
*/
int box_will_be_blocked(const struct Map * m, const struct Position mov,
	const struct Position box_pos)
{
	struct Position next_pos2, tmp, tmp2[2];
	int i;

	next_pos2.x = box_pos.x + mov.x;
	next_pos2.y = box_pos.y + mov.y;

	tmp.x = next_pos2.x + mov.x;
	tmp.y = next_pos2.y + mov.y;
	tmp2[0].x = next_pos2.x + mov.y;
	tmp2[0].y = next_pos2.y + mov.x;
	tmp2[1].x = next_pos2.x - mov.y;
	tmp2[1].y = next_pos2.y - mov.x;
	for (i=0; i < 2; i++)
	{
		if (m->man_moves[tmp.y][tmp.x] == WALL &&
			m->man_moves[tmp2[i].y][tmp2[i].x] == BOX)
		{
			return TRUE;
		}
		else if (m->man_moves[tmp.y][tmp.x] == BOX &&
			m->man_moves[tmp2[i].y][tmp2[i].x] == WALL)
		{
			return TRUE;
		}
		else if (m->man_moves[tmp.y][tmp.x] == BOX &&
			m->man_moves[tmp2[i].y][tmp2[i].x] == BOX)
		{
			return TRUE;
		}
	}

	return FALSE;
}

int is_corner_area(const struct Map * m, const struct Position p,
	const struct Position box, const struct Position new_box)
{
	int NumMoves, NewMoves;
	struct Position pos[MAX_MOVES];
	struct Position new_pos[MAX_MOVES];
	char corners[MAX_Y][MAX_X];
	int i,j;
	struct Position next_pos;
	char *next_cell;


	/* Blank the garden */
	for (j = 0; j<m->SizeY; j++)
		for (i=0; i<m->SizeX; i++)
			corners[j][i] = m->Cells[j][i];

	/* Let's put the boxes */
	for (i = 0; i<m->NumBoxes; i++)
		corners[m->Box[i].y][m->Box[i].x] = BOX;

	/* Let's put our box - it can be simply added */
	corners[new_box.y][new_box.x] = BOX;
	/* Let's remove the original box. */
	corners[box.y][box.x] = BLANK;

	NewMoves = 1;
	new_pos[0] = p;
	while (NewMoves > 0)
	{
		/* The before named "New Moves" become the moves we have
		   to analyze */
		NumMoves = NewMoves;
		for (i=0; i<NewMoves; i++)
		{
			pos[i] = new_pos[i];
		}

		/* Search new positions for each position */
		NewMoves = 0;
		for (i=0; i<NumMoves; i++)
		{
			/* For each direction */
			for (j=0; j<4; j++)
			{
				next_pos.x = pos[i].x + move_vectors[j].x;
				next_pos.y = pos[i].y + move_vectors[j].y;
				next_cell = &corners[next_pos.y][next_pos.x];
				if(*next_cell == BLANK ||
					*next_cell == PLATFORM)
				{
					return FALSE;
				}
				else if(*next_cell == CORNER)
				{
					new_pos[NewMoves] = next_pos;
					*next_cell = MANCANMOVE;
					NewMoves++;
				}
			}
		}
	}

	return TRUE;
}

int does_box_close_corners(const struct Map * m, const struct Position mov,
	const struct Position box_pos)
{
	struct Position p, p2;

	p.x = box_pos.x + mov.x;
	p.y = box_pos.y + mov.y;
	
	/* Let's plan the checks */
	/* The point will be marked with a MANCANMOVE */
	p2.x = p.x + mov.x;
	p2.y = p.y + mov.y;
	if (m->Cells[p2.y][p2.x] == CORNER)
	{
		if (is_corner_area(m, p2, box_pos, p))
			return TRUE;
	}

	p2.x = p.x + mov.y;
	p2.y = p.y + mov.x;
	if (m->Cells[p2.y][p2.x] == CORNER)
	{
		if (is_corner_area(m, p2, box_pos, p))
			return TRUE;
	}

	p2.x = p.x - mov.y;
	p2.y = p.y - mov.x;
	if (m->Cells[p2.y][p2.x] == CORNER)
	{
		if (is_corner_area(m, p2, box_pos, p))
			return TRUE;
	}
	return FALSE;
}
#endif

/*
Catch the situation where a box is moved next to a corner, where the box
next to it will not be able to be moved.
*/
static int is_dead1(const struct Map * m, const struct Position mov,
	const struct Position new_pos)
{
	struct Position opposite1, opposite2;

	/* The wall corners must exist */
	opposite1.x = -mov.y;
	opposite1.y = -mov.x;
	opposite2.x = mov.y;
	opposite2.y = mov.x;

#ifdef DEBUG
	ShowMap(m);
#endif

	/* Test the first corner */
	if (m->Cells[new_pos.y+mov.y+opposite1.y][new_pos.x+mov.x+opposite1.x]
		== WALL)
	{
		/* Test wall at opposites 1*/
		if (m->Cells[new_pos.y+opposite1.y][new_pos.x+opposite1.x]
			== WALL &&
			m->man_moves[new_pos.y+mov.y][new_pos.x+mov.x] == BOX)
		{
				return TRUE;
		}
		else
		if (m->man_moves[new_pos.y+opposite1.y][new_pos.x+opposite1.x]
			== BOX &&
			m->Cells[new_pos.y+mov.y][new_pos.x+mov.x] == WALL)
		{
				return TRUE;
		}
		/* Test wall at opposites 2 */
		if (m->Cells[new_pos.y+opposite2.y][new_pos.x+opposite2.x]
			== WALL &&
			m->man_moves[new_pos.y+mov.y][new_pos.x+mov.x] == BOX)
		{
				return TRUE;
		}
		else
		if (m->man_moves[new_pos.y+opposite2.y][new_pos.x+opposite2.x]
			== BOX &&
			m->Cells[new_pos.y+mov.y][new_pos.x+mov.x] == WALL)
		{
				return TRUE;
		}
	}

	/* Test the second corner */
	if (m->Cells[new_pos.y+mov.y+opposite2.y][new_pos.x+mov.x+opposite2.x]
		== WALL)
	{
		/* Test wall at opposites 1*/
		if (m->Cells[new_pos.y+opposite1.y][new_pos.x+opposite1.x]
			== WALL &&
			m->man_moves[new_pos.y+mov.y][new_pos.x+mov.x] == BOX)
		{
				return TRUE;
		}
		else
		if (m->man_moves[new_pos.y+opposite1.y][new_pos.x+opposite1.x]
			== BOX &&
			m->Cells[new_pos.y+mov.y][new_pos.x+mov.x] == WALL)
		{
				return TRUE;
		}
		/* Test wall at opposites 2 */
		if (m->Cells[new_pos.y+opposite2.y][new_pos.x+opposite2.x]
			== WALL &&
			m->man_moves[new_pos.y+mov.y][new_pos.x+mov.x] == BOX)
		{
				return TRUE;
		}
		else
		if (m->man_moves[new_pos.y+opposite2.y][new_pos.x+opposite2.x]
			== BOX &&
			m->Cells[new_pos.y+mov.y][new_pos.x+mov.x] == WALL)
		{
				return TRUE;
		}
	}

	return FALSE;
}

/*
Catch the situation where a corner gets surrounded by boxes.
*/
static int is_dead2(const struct Map * m, const struct Position mov,
	const struct Position new_pos)
{
	struct Position next, opposite1, opposite2;

	next.x = new_pos.x+mov.x;
	next.y = new_pos.y+mov.y;

	/* The corner must exist */
	if (m->Cells[next.y][next.x] != CORNER)
		return FALSE;


	/* The wall corners must exist */
	opposite1.x = next.x -mov.y;
	opposite1.y = next.y -mov.x;
	opposite2.x = next.x + mov.y;
	opposite2.y = next.y + mov.x;

	if (m->man_moves[opposite1.y][opposite1.x] == BOX)
	{
		if(m->Cells[opposite1.y+mov.y][opposite1.x+mov.x] == WALL
		   && m->Cells[opposite1.y-mov.y][opposite1.x-mov.x] == WALL)
		   return TRUE;
	}

	if (m->man_moves[opposite2.y][opposite2.x] == BOX)
	{
		if(m->Cells[opposite2.y+mov.y][opposite2.x+mov.x] == WALL
		   && m->Cells[opposite2.y-mov.y][opposite2.x-mov.x] == WALL)
		   return TRUE;
	}
	return FALSE;
}

static int is_box_movable(const struct Map * m, const struct Position mov,
	const struct Position box_pos)
{
	struct Position next_pos2;

	next_pos2.x = box_pos.x + mov.x;
	next_pos2.y = box_pos.y + mov.y;

	if((m->Cells[next_pos2.y][next_pos2.x] != BLANK &&
		m->Cells[next_pos2.y][next_pos2.x] != PLATFORM) ||
		m->man_moves[next_pos2.y][next_pos2.x] == BOX)
	{
		return FALSE;
	}
	else if (is_dead1(m, mov, next_pos2) == TRUE)
	{
		return FALSE;
	}
	else if (is_dead2(m, mov, next_pos2) == TRUE)
	{
		return FALSE;
	}
	return TRUE;
}

/* It modifies m->man_moves */
static int get_box_movements(struct Map * m,
	struct BoxMove movements[])
{
	struct Position pos[MAX_MOVES];
	struct Position new_pos[MAX_MOVES];
	int NumMoves, NewMoves;
	int j, i;
	struct Position next_pos;
	char *next_cell;
	int num_box_movements = 0;
	
	/* Let's  the map with only walls in man_moves - other, blanks */
	for (j = 0; j<m->SizeY; j++)
		for (i=0; i<m->SizeX; i++)
		{
			if (m->Cells[j][i] == WALL)
				m->man_moves[j][i] = WALL;
			else
				m->man_moves[j][i] = BLANK;
		}

	/* Let's put the boxes */
	for (i = 0; i<m->NumBoxes; i++)
	{
		m->man_moves[m->Box[i].y][m->Box[i].x] = BOX;
		m->cells_boxes[m->Box[i].y][m->Box[i].x] = i;
	}

	NewMoves = 1;
	new_pos[0].x = m->Man.x;
	new_pos[0].y = m->Man.y;
	m->man_moves[m->Man.y][m->Man.x] = MANCANMOVE;
	while (NewMoves > 0)
	{
		/* The before named "New Moves" become the moves we have
		   to analyze */
		NumMoves = NewMoves;
		for (i=0; i<NewMoves; i++)
		{
			pos[i] = new_pos[i];
		}

		/* Search new positions for each position */
		NewMoves = 0;
		for (i=0; i<NumMoves; i++)
		{
			/* For each direction */
			for (j=0; j<4; j++)
			{
				next_pos.x = pos[i].x + move_vectors[j].x;
				next_pos.y = pos[i].y + move_vectors[j].y;
				next_cell = &m->man_moves[next_pos.y][next_pos.x];
				if(*next_cell == BLANK)
				{
					new_pos[NewMoves] = next_pos;
					*next_cell = MANCANMOVE;
					NewMoves++;
				}
				else if (*next_cell == BOX)
				{
						
					/* Check if the box is movable */

					if (is_box_movable(m, move_vectors[j],
						next_pos ))
					{
						{
					movements[num_box_movements].box =
					m->cells_boxes[next_pos.y][next_pos.x];
					movements[num_box_movements].dir =
					move_vectors[j];
					num_box_movements++;
						}
					}
					
				}

			}
		}
	}

	return num_box_movements;
}

static void force_move_box(struct Map *m, const struct BoxMove move)
{
	struct Position newpos;


	/* Add coords */
	newpos.x = m->Box[move.box].x + move.dir.x;
	newpos.y = m->Box[move.box].y + move.dir.y;

	/* Be certain the move can be done */
	assert(m->Cells[newpos.y][newpos.x] != BOX);
	assert(m->Cells[newpos.y][newpos.x] != WALL);

	/* Control if we moved the box to a platform */
	if(m->Cells[newpos.y][newpos.x] == PLATFORM)
	{
		m->NumBoxesInPlatform++;
	}

	/* Control if we moved the box from a platform */
	if (m->Cells[m->Box[move.box].y][m->Box[move.box].x] == PLATFORM)
	{
		m->NumBoxesInPlatform--;
	}
	m->Man = m->Box[move.box];

	m->Box[move.box] = newpos;
}



static int search_depth(struct Map maps[], int depth,
	struct BoxMove movements[],
	int num_movements, float percent, float total_percent)
{
	struct BoxMove new_movements[MAX_MOVES];
	int num_new_movements;
	struct Map *m; 
	int i;
	float next_percent;

	next_percent = percent / num_movements;

	m = &maps[depth+1];
	if (depth > max_depth)
		max_depth = depth;
	if (depth > max_depth_period)
		max_depth_period = depth;
	if (depth < min_depth_period)
		min_depth_period = depth;

	for (i=0; i < num_movements; i++)
	{
		CopyMap(m, &maps[depth]);
		force_move_box(m, movements[i]);
		if (m->NumPlatforms == m->NumBoxesInPlatform)
		{
			PrintMove(movements[i]);
			actual_map = &maps[depth+1];
			show_percent_and_map();
			return 0;
		}

		if (is_new_map(maps, depth+1))
		{
			num_new_movements = get_box_movements(m, new_movements);
			assert(num_new_movements < MAX_MOVES);
		}
		else
			num_new_movements = 0;

		if (num_new_movements == 0)
		{
			percent_to_show = total_percent + next_percent*i;
			depth_to_show = depth;
			actual_map = &maps[depth];
#ifdef DEBUG		/* to be out */
			show_percent_and_map();
#endif
	
		}
		else
		{
			if (depth+1 < MAX_STEPS)
			{
				if(search_depth(maps, depth+1, new_movements,
					num_new_movements, next_percent,
					total_percent + next_percent*i) == 0)
				{
					PrintMove(movements[i]);
					actual_map = &maps[depth+1];
					show_percent_and_map();
					return 0;
				}
			}
		}
	}
	return 1;
}


int solve_map(const struct Map *origin)
{
	struct Map *maps;
	struct BoxMove new_movements[MAX_MOVES];
	int num_new_movements;
	int ret;

	maps = malloc(sizeof(*maps) * (MAX_STEPS+1));

	CopyMap(&maps[0], origin);

	num_new_movements = get_box_movements(&maps[0], new_movements);
	assert(num_new_movements < MAX_MOVES);
	assert(num_new_movements > 0);

	init_os();

	ret = search_depth(maps, 0, new_movements,
		num_new_movements, 100. / num_new_movements,
		0);
	free(maps);
	return ret;
}