/***************************************************************************
 view_1.c Copyright (C) 2000 Christoph Reichenbach


 This program may be modified and copied freely according to the terms of
 the GNU general public license (GPL), as long as the above copyright
 notice and the licensing information contained herein are preserved.

 Please refer to www.gnu.org for licensing details.

 This work is provided AS IS, without warranty of any kind, expressed or
 implied, including but not limited to the warranties of merchantibility,
 noninfringement, and fitness for a specific purpose. The author will not
 be held liable for any damage caused by this work or derivatives of it.

 By using this source code, you agree to the licensing terms as stated
 above.


 Please contact the maintainer for bug reports or inquiries.

 Current Maintainer:

    Christoph Reichenbach (CR) <jameson@linuxgames.com>

***************************************************************************/
/* SCI 1 view resource defrobnicator */

#include "sci/include/sci_memory.h"
#include "sci/include/gfx_system.h"
#include "sci/include/gfx_resource.h"
#include "sci/include/gfx_tools.h"

#define V1_LOOPS_NR_OFFSET 0
#define V1_MIRROR_MASK 2
#define V1_PALETTE_OFFSET 6
#define V1_FIRST_LOOP_OFFSET 8

#define V1_RLE 0x80 /* run-length encode? */
#define V1_RLE_BG 0x40 /* background fill */

#define NEXT_RUNLENGTH_BYTE(n) \
  if (literal_pos == runlength_pos) \
    literal_pos += n; \
  runlength_pos += n; 

#define NEXT_LITERAL_BYTE(n) \
  if (literal_pos == runlength_pos) \
    runlength_pos += n; \
  literal_pos += n; 

static int
decompress_sci_view(int id, int loop, int cel, byte *resource, byte *dest, int mirrored, int pixmap_size, int size, 
		    int runlength_pos, int literal_pos, int xl, int yl, int color_key)
{
	int writepos = mirrored? xl : 0;

	if (mirrored) {
		int linebase = 0;

		while (linebase < pixmap_size && literal_pos < size && runlength_pos < size) {
			int op = resource[runlength_pos];
			int bytes;
			int readbytes = 0;
			int color = 0;

			NEXT_RUNLENGTH_BYTE(1);

			if (op & V1_RLE) {
				bytes = op & 0x3f;
				op &= (V1_RLE | V1_RLE_BG);
				readbytes = (op & V1_RLE_BG)? 0 : 1;
			} else {
				readbytes = bytes = op & 0x3f;
				op = 0;
			}

			if (runlength_pos + readbytes > size)
			{
				GFXWARN("View %02x:(%d/%d) requires %d bytes to be read when %d are available at pos %d\n",
					id, loop, cel, readbytes, size - runlength_pos, runlength_pos-1);
				return 1;
			}
/*
			if (writepos - bytes < 0) {
				GFXWARN("View %02x:(%d/%d) describes more bytes than needed: %d/%d bytes at rel. offset 0x%04x\n",
					id, loop, cel, writepos - bytes, pixmap_size, pos - 1);
				bytes = pixmap_size - writepos;
			}
*/			
			if (op==V1_RLE) 
			{
				color = resource[literal_pos];
				NEXT_LITERAL_BYTE(1);
			}

			if (!op && literal_pos + bytes > size)
			{
				GFXWARN("View %02x:(%d/%d) requires %d bytes to be read when %d are available at pos %d\n",
					id, loop, cel, bytes, size - literal_pos, literal_pos-1);
				return 1;
			}

			while (bytes--)
			{
				if (op) {
					if (op & V1_RLE_BG) {
						writepos--;
						*(dest + writepos) = color_key;
					} else {
						writepos--;
						*(dest + writepos) = color;
					}
				} else {
					writepos--;
					*(dest + writepos) = *(resource + literal_pos);
					NEXT_LITERAL_BYTE(1);
					
				}
				if (writepos == linebase)
				{
					writepos+=2*xl;
					linebase+=xl;
				}
			}
		}
	}
        else {
		while (writepos < pixmap_size && literal_pos < size && runlength_pos < size) {
			int op = resource[runlength_pos];
			int bytes;
			int readbytes = 0;

			NEXT_RUNLENGTH_BYTE(1);

			if (op & V1_RLE) {
				bytes = op & 0x3f;
				op &= (V1_RLE | V1_RLE_BG);
				readbytes = (op & V1_RLE_BG)? 0 : 1;
			} else {
				readbytes = bytes = op & 0x3f;
				op = 0;
			}

			if (runlength_pos + readbytes > size) {
				return 1;
			}

			if (writepos + bytes > pixmap_size) {
				GFXWARN("View %02x:(%d/%d) describes more bytes than needed: %d/%d bytes at rel. offset 0x%04x\n",
					id, loop, cel, writepos-bytes, pixmap_size, runlength_pos - 1);
				bytes = pixmap_size - writepos;
			}

			if (!op && literal_pos + bytes > size)
			{
				GFXWARN("View %02x:(%d/%d) requires %d bytes to be read when %d are available at pos %d\n",
					id, loop, cel, bytes, size - literal_pos, literal_pos-1);
				return 1;
			}

			if (writepos + bytes > pixmap_size)
			{
				GFXWARN("Writing out of bounds: %d bytes at %d > size %d\n", bytes, writepos, pixmap_size);
			}
					
			if (op) {
				if (op & V1_RLE_BG)
					memset(dest + writepos, color_key, bytes);
				else {
					int color = resource[literal_pos];

					NEXT_LITERAL_BYTE(1);
					memset(dest + writepos, color, bytes);
				}
			} else {
				memcpy(dest + writepos, resource + literal_pos, bytes);
				NEXT_LITERAL_BYTE(bytes);
			}
			writepos += bytes;

		}

	};

	return 0;
}

static int
decompress_sci_view_amiga(int id, int loop, int cel, byte *resource, byte *dest, int mirrored, int pixmap_size, int size, 
		    int pos, int xl, int yl, int color_key)
{
	int writepos = mirrored? xl - 1 : 0;

	while (writepos < pixmap_size && pos < size) {
		int op = resource[pos++];
		int bytes;
		int color;

		if (op & 0x07) {
			bytes = op & 0x07;
			color = op >> 3;
		} else {
			bytes = op >> 3;
			color = color_key;
		}

		if (mirrored) {
			while (bytes--) {
				dest[writepos--] = color;
				/* If we've just written the first pixel of a line... */
				if (!((writepos + 1) % xl)) {
					/* Then move to the end of next line */
					writepos += 2 * xl;

					if (writepos >= pixmap_size && bytes)
					{
						GFXWARN("View %02x:(%d/%d) writing out of bounds\n", id, loop, cel);
						break;
					}
				}
			}
		} else {
			if (writepos + bytes > pixmap_size) {
				GFXWARN("View %02x:(%d/%d) describes more bytes than needed: %d/%d bytes at rel. offset 0x%04x\n",
					id, loop, cel, writepos-bytes, pixmap_size, pos - 1);
				bytes = pixmap_size - writepos;
			}
			memset(dest + writepos, color, bytes);
			writepos += bytes;
		}
	}

	if (writepos < pixmap_size) {
			GFXWARN("View %02x:(%d/%d) not enough pixel data in view\n", id, loop, cel);
			return 1;
	}

	return 0;
}

gfx_pixmap_t *
gfxr_draw_cel1(int id, int loop, int cel, int mirrored, byte *resource, int size, gfxr_view_t *view, int amiga_game)
{
	int xl = get_int_16(resource);
	int yl = get_int_16(resource + 2);
	int xhot = (gint8) resource[4];
	int yhot = (guint8) resource[5];
	int pos = 8;
	int pixmap_size = xl * yl;
	gfx_pixmap_t *retval = gfx_pixmap_alloc_index_data(gfx_new_pixmap(xl, yl, id, loop, cel));
	byte *dest = retval->index_data;
	int decompress_failed;

	retval->color_key = resource[6];
	retval->xoffset = (mirrored)? xhot : -xhot;
	retval->yoffset = -yhot;

	if (view) {
		retval->colors = view->colors;
		retval->colors_nr = view->colors_nr;
	}
		
	retval->flags |= GFX_PIXMAP_FLAG_EXTERNAL_PALETTE;

	if (xl <= 0 || yl <= 0) {
		gfx_free_pixmap(NULL, retval);
		GFXERROR("View %02x:(%d/%d) has invalid xl=%d or yl=%d\n", id, loop, cel, xl, yl);
		return NULL;
	}

	if (amiga_game)
		decompress_failed = decompress_sci_view_amiga(id, loop, cel,
			resource, dest, mirrored, pixmap_size, size, pos, 
			xl, yl, retval->color_key);
	else
		decompress_failed = decompress_sci_view(id, loop, cel,
			resource, dest, mirrored, pixmap_size, size, pos, 
			pos, xl, yl, retval->color_key);

	if (decompress_failed) {
		gfx_free_pixmap(NULL, retval);
		return NULL;
	}

	return retval;
}

static int
gfxr_draw_loop1(gfxr_loop_t *dest, int id, int loop, int mirrored, byte *resource, int offset, int size, gfxr_view_t *view, int amiga_game)
{
	int i;
	int cels_nr = get_int_16(resource + offset);

	if (get_uint_16(resource + offset + 2)) {
		GFXWARN("View %02x:(%d): Gray magic %04x in loop, expected white\n", id, loop, get_uint_16(resource + offset + 2));
	}

	if (cels_nr * 2 + 4 + offset > size) {
		GFXERROR("View %02x:(%d): Offset array for %d cels extends beyond resource space\n", id, loop, cels_nr);
		dest->cels_nr = 0; /* Mark as "delete no cels" */
		dest->cels = NULL;
		return 1;
	}

	dest->cels = (gfx_pixmap_t**)sci_malloc(sizeof(gfx_pixmap_t *) * cels_nr);

	for (i = 0; i < cels_nr; i++) {
		int cel_offset = get_uint_16(resource + offset + 4 + (i << 1));
		gfx_pixmap_t *cel;

		if (cel_offset >= size) {
			GFXERROR("View %02x:(%d/%d) supposed to be at illegal offset 0x%04x\n", id, loop, i, cel_offset);
			cel = NULL;
		} else
			cel = gfxr_draw_cel1(id, loop, i, mirrored, resource + cel_offset, size - cel_offset, view, amiga_game);

		if (!cel) {
			dest->cels_nr = i;
			return 1;
		}

		dest->cels[i] = cel;
	}

	dest->cels_nr = cels_nr;

	return 0;
}


#define V1_FIRST_MAGIC 1
#define V1_MAGICS_NR 5
/*static byte view_magics[V1_MAGICS_NR] = {0x80, 0x00, 0x00, 0x00, 0x00};*/

gfxr_view_t *
gfxr_draw_view1(int id, byte *resource, int size, gfx_pixmap_color_t *static_pal,
		int static_pal_nr)
{
	int i;
	int palette_offset;
	gfxr_view_t *view;
	int mirror_mask;
	int amiga_game = 0;

	if (size < V1_FIRST_LOOP_OFFSET + 8) {
		GFXERROR("Attempt to draw empty view %04x\n", id);
		return NULL;
	}

	view = (gfxr_view_t*)sci_malloc(sizeof(gfxr_view_t));
	view->ID = id;
	view->flags = 0;

	view->loops_nr = resource[V1_LOOPS_NR_OFFSET];
	palette_offset = get_uint_16(resource + V1_PALETTE_OFFSET);
	mirror_mask = get_uint_16(resource + V1_MIRROR_MASK);

	if (view->loops_nr * 2 + V1_FIRST_LOOP_OFFSET > size) {
		GFXERROR("View %04x: Not enough space in resource to accomodate for the claimed %d loops\n", id, view->loops_nr);
		free(view);
		return NULL;
	}

/*	fprintf(stderr, "View flags are 0x%02x\n", resource[3]);*/

/*
	for (i = 0; i < V1_MAGICS_NR; i++)
		if (resource[V1_FIRST_MAGIC + i] != view_magics[i]) {
			GFXWARN("View %04x: View magic #%d should be %02x but is %02x\n",
				id, i, view_magics[i], resource[V1_FIRST_MAGIC + i]);
		}
*/

	if (palette_offset > 0)
	{
	    if (palette_offset > size) {
		GFXERROR("Palette is outside of view %04x\n", id);
		free(view);
		return NULL;
	    }   
	    if (!(view->colors = gfxr_read_pal1(id, &(view->colors_nr),
						resource + palette_offset, size - palette_offset))) {
		GFXERROR("view %04x: Palette reading failed. Aborting...\n", id);
		free(view);
		return NULL;
	    }
	} else if (static_pal_nr == GFX_SCI1_AMIGA_COLORS_NR) {
		/* Assume we're running an amiga game. */
		amiga_game = 1;
		view->colors = static_pal;
		view->colors_nr = static_pal_nr;
		view->flags |= GFX_PIXMAP_FLAG_EXTERNAL_PALETTE;
	} else {
	    GFXWARN("view %04x: Doesn't have a palette. Can FreeSCI handle this?\n", view->ID);
	    view->colors = NULL;
	    view->colors_nr = 0;
	}

	view->loops = (gfxr_loop_t*)sci_malloc(sizeof (gfxr_loop_t) * view->loops_nr);

	for (i = 0; i < view->loops_nr; i++) {
		int error_token = 0;
		int loop_offset = get_uint_16(resource + V1_FIRST_LOOP_OFFSET + (i << 1));

		if (loop_offset >= size) {
			GFXERROR("View %04x:(%d) supposed to be at illegal offset 0x%04x\n", id, i);
			error_token = 1;
		}

		if (error_token || gfxr_draw_loop1(view->loops + i, id, i, mirror_mask & (1<<i), 
						   resource, loop_offset, size, view, amiga_game)) {
			/* An error occured */
			view->loops_nr = i;
			gfxr_free_view(NULL, view);
			return NULL;
		}
	}

	return view;
}

#define V2_HEADER_SIZE 0
#define V2_LOOPS_NUM 2
#define V2_PALETTE_OFFSET 8
#define V2_BYTES_PER_LOOP 12
#define V2_BYTES_PER_CEL 13

#define V2_IS_MIRROR 1
#define V2_COPY_OF_LOOP 2
#define V2_CELS_NUM 4
#define V2_LOOP_OFFSET 14

#define V2_CEL_WIDTH 0
#define V2_CEL_HEIGHT 2
#define V2_X_DISPLACEMENT 4
#define V2_Y_DISPLACEMENT 6
#define V2_COLOR_KEY 8
#define V2_RUNLENGTH_OFFSET 24
#define V2_LITERAL_OFFSET 28

gfx_pixmap_t *
gfxr_draw_cel11(int id, int loop, int cel, int mirrored, byte *resource_base, byte *cel_base, int size, gfxr_view_t *view)
{
	int xl = get_uint_16(cel_base + V2_CEL_WIDTH);
	int yl = get_uint_16(cel_base + V2_CEL_HEIGHT);
	int xdisplace = get_uint_16(cel_base + V2_X_DISPLACEMENT);
	int ydisplace = get_uint_16(cel_base + V2_Y_DISPLACEMENT);
	int runlength_offset = get_uint_16(cel_base + V2_RUNLENGTH_OFFSET);
	int literal_offset = get_uint_16(cel_base + V2_LITERAL_OFFSET);
	int pixmap_size = xl * yl;
	
	gfx_pixmap_t *retval = gfx_pixmap_alloc_index_data(gfx_new_pixmap(xl, yl, id, loop, cel));
	byte *dest = retval->index_data;
	int decompress_failed;

	retval->color_key = cel_base[V2_COLOR_KEY];
	retval->xoffset = (mirrored)? xdisplace : -xdisplace;
	retval->yoffset = -ydisplace;

	if (view) {
		retval->colors = view->colors;
		retval->colors_nr = view->colors_nr;
	}
		
	retval->flags |= GFX_PIXMAP_FLAG_EXTERNAL_PALETTE;

	if (xl <= 0 || yl <= 0) {
		gfx_free_pixmap(NULL, retval);
		GFXERROR("View %02x:(%d/%d) has invalid xl=%d or yl=%d\n", id, loop, cel, xl, yl);
		return NULL;
	}

	decompress_failed = decompress_sci_view(id, loop, cel, resource_base, dest, mirrored, pixmap_size, size,
						runlength_offset, literal_offset, xl, yl, retval->color_key);

	if (decompress_failed) {
		gfx_free_pixmap(NULL, retval);
		return NULL;
	}

	return retval;
}

gfxr_loop_t *
gfxr_draw_loop11(int id, int loop, int mirrored, byte *resource_base, byte *loop_base, int size, int cels_nr,
		 gfxr_loop_t *result, gfxr_view_t *view, int bytes_per_cel)
{
	byte *seeker = loop_base;
	int i;

	result->cels_nr = cels_nr;
	result->cels = (gfx_pixmap_t **)
		sci_malloc(sizeof(gfx_pixmap_t *) * cels_nr);

	for (i = 0; i < cels_nr; i++)
	{
		result->cels[i] = gfxr_draw_cel11(id, loop, i, mirrored, resource_base, seeker, size, view);
		seeker += bytes_per_cel;
	}

	return result;
}

gfxr_view_t *
gfxr_draw_view11(int id, byte *resource, int size)
{
	gfxr_view_t *view;
 	int header_size = get_uint_16(resource + V2_HEADER_SIZE);
	int palette_offset = get_uint_16(resource + V2_PALETTE_OFFSET);
	int bytes_per_loop = resource[V2_BYTES_PER_LOOP];
	int loops_num = resource[V2_LOOPS_NUM];
	int bytes_per_cel = resource[V2_BYTES_PER_CEL];
	int i;
	byte *seeker;

	view = (gfxr_view_t*)sci_malloc(sizeof(gfxr_view_t));

	memset(view, 0, sizeof(gfxr_view_t));
	view->ID = id;
	view->flags = 0;

	view->loops_nr = loops_num;
	view->loops = (gfxr_loop_t *)calloc(view->loops_nr, sizeof(gfxr_loop_t));

	/* There is no indication of size here, but this is certainly large enough */
	view->colors = gfxr_read_pal11(id, &view->colors_nr, resource + palette_offset, 1284); 
 
	seeker = resource + header_size;
	for (i = 0; i < view->loops_nr; i++)
	{
		static char *truth[2] = {"not ",""};
		int loop_offset = get_uint_16(seeker + V2_LOOP_OFFSET);
		int cels = seeker[V2_CELS_NUM];
		int mirrored = seeker[V2_IS_MIRROR];
		int copy_entry = seeker[V2_COPY_OF_LOOP];

		printf("%d\n", mirrored);
		if (copy_entry == 255)
			gfxr_draw_loop11(id, i, 0, resource, resource + loop_offset, size, cels, view->loops + i, 
					 view, bytes_per_cel); else
					 {
						 byte *temp = resource + header_size + copy_entry * bytes_per_loop;
						 loop_offset = get_uint_16(temp + V2_LOOP_OFFSET);
						 cels = temp[V2_CELS_NUM];
						 gfxr_draw_loop11(id, i, 1, resource, resource + loop_offset, size, cels, 
								  view->loops + i, view, bytes_per_cel);
					 }
						 
		seeker += bytes_per_loop;
	}

	return view;
}