/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

/*
 * This code is based on original Soltys source code
 * Copyright (c) 1994-1995 Janus B. Wisniewski and L.K. Avalon
 */

#include "cge/bitmap.h"
#include "cge/cfile.h"
#include "cge/jbw.h"
#include "cge/vol.h"
#include "cge/cfile.h"
#include "cge/vga13h.h"
#include "common/system.h"

namespace CGE {

DAC *BITMAP::Pal = NULL;
#define MAXPATH  128

void BITMAP::init() {
	Pal = NULL;
}

void BITMAP::deinit() {
}

#pragma argsused
BITMAP::BITMAP(const char *fname, bool rem) : M(NULL), V(NULL) {
	char pat[MAXPATH];
	ForceExt(pat, fname, ".VBM");

#if (BMP_MODE < 2)
	if (rem && PIC_FILE::Exist(pat)) {
		PIC_FILE file(pat);
		if ((file.Error == 0) && (!VBMLoad(&file)))
			error("Bad VBM [%s]", fname);
	} else
#endif
	{
#if (BMP_MODE)
		ForceExt(pat, fname, ".BMP");
		PIC_FILE file(pat);
		if (file.Error == 0) {
			if (BMPLoad(&file)) {
				Code();
				if (rem) {
					free(M);
					M = NULL;
				}
			} else
				error("Bad BMP [%s]", fname);
		}
#else
		error("Bad VBM [%s]", fname);
#endif
	}
}


BITMAP::BITMAP(uint16 w, uint16 h, uint8 *map) : W(w), H(h), M(map), V(NULL) {
	if (map)
		Code();
}


// following routine creates filled rectangle
// immediately as VGA video chunks, in near memory as fast as possible,
// especially for text line real time display
BITMAP::BITMAP(uint16 w, uint16 h, uint8 fill)
	: W((w + 3) & ~3),                              // only full uint32 allowed!
	  H(h),
	  M(NULL) {
	uint16 dsiz = W >> 2;                           // data size (1 plane line size)
	uint16 lsiz = 2 + dsiz + 2;                     // uint16 for line header, uint16 for gap
	uint16 psiz = H * lsiz;                         // - last gape, but + plane trailer
	uint8 *v = new uint8[4 * psiz + H * sizeof(*B)];// the same for 4 planes
	                                                // + room for wash table
	if (v == NULL)
		error("No core");

	*(uint16 *) v = CPY | dsiz;                     // data chunk hader
	memset(v + 2, fill, dsiz);                      // data bytes
	*(uint16 *)(v + lsiz - 2) = SKP | ((SCR_WID / 4) - dsiz);  // gap
	memcpy(v + lsiz, v, psiz - lsiz);               // tricky replicate lines
	*(uint16 *)(v + psiz - 2) = EOI;                // plane trailer uint16
	memcpy(v + psiz, v, 3 * psiz);                  // tricky replicate planes
	HideDesc *b = (HideDesc *)(v + 4 * psiz);
	b->skip = (SCR_WID - W) >> 2;
	b->hide = W >> 2;
	memcpy(b + 1, b, (H - 1) * sizeof(*b));         // tricky fill entire table
	b->skip = 0;                                    // fix the first entry
	V = v;
	B = b;
}


BITMAP::BITMAP(const BITMAP &bmp) : W(bmp.W), H(bmp.H), M(NULL), V(NULL) {
	uint8 *v0 = bmp.V;
	if (v0) {
		uint16 vsiz = (uint8 *)(bmp.B) - (uint8 *)(v0);
		uint16 siz = vsiz + H * sizeof(HideDesc);
		uint8 *v1 = farnew(uint8, siz);
		if (v1 == NULL)
			error("No core");
		memcpy(v1, v0, siz);
		B = (HideDesc *)((V = v1) + vsiz);
	}
}


BITMAP::~BITMAP(void) {
	if (MemType(M) == FAR_MEM)
		free(M);

	switch (MemType(V)) {
	case NEAR_MEM :
		delete[](uint8 *) V;
		break;
	case FAR_MEM  :
		free(V);
		break;
	}
}


BITMAP &BITMAP::operator = (const BITMAP &bmp) {
	uint8 *v0 = bmp.V;
	W = bmp.W;
	H = bmp.H;
	M = NULL;
	if (MemType(V) == FAR_MEM)
		free(V);
	if (v0 == NULL)
		V = NULL;
	else {
		uint16 vsiz = (uint8 *)bmp.B - (uint8 *)v0;
		uint16 siz = vsiz + H * sizeof(HideDesc);
		uint8 *v1 = farnew(uint8, siz);
		if (v1 == NULL)
			error("No core");
		memcpy(v1, v0, siz);
		B = (HideDesc *)((V = v1) + vsiz);
	}
	return *this;
}


uint16 BITMAP::MoveVmap(uint8 *buf) {
	if (V) {
		uint16 vsiz = (uint8 *)B - (uint8 *)V;
		uint16 siz = vsiz + H * sizeof(HideDesc);
		memcpy(buf, V, siz);
		if (MemType(V) == FAR_MEM)
			free(V);
		B = (HideDesc *)((V = buf) + vsiz);
		return siz;
	}
	return 0;
}


BMP_PTR BITMAP::Code(void) {
	if (M) {
		uint16 i, cnt;

		if (V) {                                        // old X-map exists, so remove it
			switch (MemType(V)) {
			case NEAR_MEM :
				delete[](uint8 *) V;
				break;
			case FAR_MEM  :
				free(V);
				break;
			}
			V = NULL;
		}

		while (true) {                                  // at most 2 times: for (V == NULL) & for allocated block;
			uint8 *im = V + 2;
			uint16 *cp = (uint16 *) V;
			int bpl;

			if (V) {                                      // 2nd pass - fill the hide table
				for (i = 0; i < H; i++) {
					B[i].skip = 0xFFFF;
					B[i].hide = 0x0000;
				}
			}
			for (bpl = 0; bpl < 4; bpl++) {              // once per each bitplane
				uint8 *bm = M;
				bool skip = (bm[bpl] == TRANS);
				uint16 j;

				cnt = 0;
				for (i = 0; i < H; i++) {                  // once per each line
					uint8 pix;
					for (j = bpl; j < W; j += 4) {
						pix = bm[j];
						if (V && pix != TRANS) {
							if (j < B[i].skip)
								B[i].skip = j;

							if (j >= B[i].hide)
								B[i].hide = j + 1;
						}
						if ((pix == TRANS) != skip || cnt >= 0x3FF0) { // end of block
							cnt |= (skip) ? SKP : CPY;
							if (V)
								*cp = cnt;                          // store block description uint16

							cp = (uint16 *) im;
							im += 2;
							skip = (pix == TRANS);
							cnt = 0;
						}
						if (! skip) {
							if (V)
								*im = pix;
							++ im;
						}
						++ cnt;
					}

					bm += W;
					if (W < SCR_WID) {
						if (skip) {
							cnt += (SCR_WID - j + 3) / 4;
						} else {
							cnt |= CPY;
							if (V)
								*cp = cnt;

							cp = (uint16 *) im;
							im += 2;
							skip = true;
							cnt = (SCR_WID - j + 3) / 4;
						}
					}
				}
				if (cnt && ! skip) {
					cnt |= CPY;
					if (V)
						*cp = cnt;

					cp = (uint16 *) im;
					im += 2;
				}
				if (V)
					*cp = EOI;
				cp = (uint16 *) im;
				im += 2;
			}
			if (V)
				break;

			uint16 sizV = (uint16)(im - 2 - V);
			V = farnew(uint8, sizV + H * sizeof(*B));
			if (! V)
				error("No core");

			B = (HideDesc *)(V + sizV);
		}
		cnt = 0;
		for (i = 0; i < H; i++) {
			if (B[i].skip == 0xFFFF) {                    // whole line is skipped
				B[i].skip = (cnt + SCR_WID) >> 2;
				cnt = 0;
			} else {
				uint16 s = B[i].skip & ~3;
				uint16 h = (B[i].hide + 3) & ~3;
				B[i].skip = (cnt + s) >> 2;
				B[i].hide = (h - s) >> 2;
				cnt = SCR_WID - h;
			}
		}
	}
	return this;
}


bool BITMAP::SolidAt(int x, int y) {
	uint8 *m;
	uint16 r, n, n0;

	if ((x >= W) || (y >= H))
		return false;

	m = V;
	r = x % 4;
	n0 = (SCR_WID * y + x) / 4, n = 0;

	while (r) {
		uint16 w, t;

		w = *(uint16 *) m;
		m += 2;
		t = w & 0xC000;
		w &= 0x3FFF;

		switch (t) {
		case EOI :
			-- r;
		case SKP :
			w = 0;
			break;
		case REP :
			w = 1;
			break;
		}
		m += w;
	}

	while (true) {
		uint16 w, t;

		w = *(uint16 *) m;
		m += 2;
		t = w & 0xC000;
		w &= 0x3FFF;

		if (n > n0)
			return false;

		n += w;
		switch (t) {
		case EOI :
			return false;
		case SKP :
			w = 0;
			break;
		case REP :
		case CPY :
			if (n - w <= n0 && n > n0)
				return true;
			break;
		}
		m += ((t == REP) ? 1 : w);
	}
}


bool BITMAP::VBMSave(XFILE *f) {
	uint16 p = (Pal != NULL),
	       n = ((uint16)(((uint8 *)B) - V)) + H * sizeof(HideDesc);
	if (f->Error == 0)
		f->Write((uint8 *)&p, sizeof(p));

	if (f->Error == 0)
		f->Write((uint8 *)&n, sizeof(n));

	if (f->Error == 0)
		f->Write((uint8 *)&W, sizeof(W));

	if (f->Error == 0)
		f->Write((uint8 *)&H, sizeof(H));

	if (f->Error == 0)
		if (p)
			f->Write((uint8 *)Pal, 256 * 3);

	if (f->Error == 0)
		f->Write(V, n);

	return (f->Error == 0);
}


bool BITMAP::VBMLoad(XFILE *f) {
	uint16 p = 0, n = 0;
	if (f->Error == 0)
		f->Read((uint8 *)&p, sizeof(p));

	if (f->Error == 0)
		f->Read((uint8 *)&n, sizeof(n));

	if (f->Error == 0)
		f->Read((uint8 *)&W, sizeof(W));

	if (f->Error == 0)
		f->Read((uint8 *)&H, sizeof(H));

	if (f->Error == 0) {
		if (p) {
			if (Pal) {
				byte palData[PAL_SIZ];
				f->Read(palData, PAL_SIZ);
				VGA::pal2DAC(palData, Pal);
			} else
				f->Seek(f->Mark() + PAL_SIZ);
		}
	}
	if ((V = farnew(uint8, n)) == NULL)
		return false;

	if (f->Error == 0)
		f->Read(V, n);

	B = (HideDesc *)(V + n - H * sizeof(HideDesc));
	return (f->Error == 0);
}
} // End of namespace CGE