/*
 *  Copyright (C) 2002  The DOSBox Team
 *
 *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/* Character displaying moving functions */

#include "dosbox.h"
#include "bios.h"
#include "mem.h"
#include "inout.h"
#include "int10.h"

static INLINE void PLANAR4_CopyRow(VGAMODES * curmode,Bit8u cleft,Bit8u cright,Bit8u rold,Bit8u rnew,PhysPt base) {
	PhysPt src,dest;Bitu copy;
	dest=base+(curmode->twidth*rnew)*curmode->cheight+cleft;	
	src=base+(curmode->twidth*rold)*curmode->cheight+cleft;	
	Bitu nextline=curmode->twidth;
	/* Setup registers correctly */
	IO_Write(0x3ce,5);IO_Write(0x3cf,1);		/* Memory transfer mode */
	IO_Write(0x3c4,2);IO_Write(0x3c5,0xf);		/* Enable all Write planes */
	/* Do some copying */
	Bitu rowsize=(cright-cleft);
	copy=curmode->cheight;
	for (;copy>0;copy--) {
		for (Bitu x=0;x<rowsize;x++) mem_writeb(dest+x,mem_readb(src+x));
		dest+=nextline;src+=nextline;

	}
	/* Restore registers */
	IO_Write(0x3ce,5);IO_Write(0x3cf,0);		/* Normal transfer mode */
}


static INLINE void TEXT_CopyRow(VGAMODES * curmode,Bit8u cleft,Bit8u cright,Bit8u rold,Bit8u rnew,PhysPt base) {
	PhysPt src,dest;
	src=base+(rold*curmode->twidth+cleft)*2;
	dest=base+(rnew*curmode->twidth+cleft)*2;
	MEM_BlockCopy(dest,src,(cright-cleft)*2);
}

static INLINE void PLANAR4_FillRow(VGAMODES * curmode,Bit8u cleft,Bit8u cright,Bit8u row,PhysPt base,Bit8u attr) {
	/* Set Bitmask / Color / Full Set Reset */
	IO_Write(0x3ce,0x8);IO_Write(0x3cf,0xff);
	IO_Write(0x3ce,0x0);IO_Write(0x3cf,attr);
	IO_Write(0x3ce,0x1);IO_Write(0x3cf,0xf);
	/* Write some bytes */
	PhysPt dest;
	dest=base+(curmode->twidth*row)*curmode->cheight+cleft;	
	Bitu nextline=curmode->twidth;
	Bitu copy=curmode->cheight;	Bitu rowsize=(cright-cleft);
	for (;copy>0;copy--) {
		for (Bitu x=0;x<rowsize;x++) mem_writeb(dest+x,0xff);
		dest+=nextline;
	}
}

static INLINE void TEXT_FillRow(VGAMODES * curmode,Bit8u cleft,Bit8u cright,Bit8u row,PhysPt base,Bit8u attr) {
	/* Do some filing */
	PhysPt dest;
	dest=base+(row*curmode->twidth+cleft)*2;
	Bit16u fill=(attr<<8)+' ';
	for (Bit8u x=0;x<(cright-cleft);x++) {
		mem_writew(dest,fill);
		dest+=2;
	}
	
}


void INT10_ScrollWindow(Bit8u rul,Bit8u cul,Bit8u rlr,Bit8u clr,Bit8s nlines,Bit8u attr,Bit8u page) {
	
	/* Do some range checking */
	BIOS_NCOLS;BIOS_NROWS;
	if(rul>rlr) return;
	if(cul>clr) return;
	if(rlr>=nrows) rlr=(Bit8u)nrows-1;
	if(clr>=ncols) clr=(Bit8u)ncols-1;
	clr++;
	/* Get the correct page */
	if(page==0xFF) page=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	VGAMODES * curmode=GetCurrentMode();	
	PhysPt base=PhysMake(curmode->sstart,curmode->slength*page);

	/* See how much lines need to be copies */
	Bit8u start,end;Bits next;
	/* Copy some lines */
	if (nlines>0) {
		start=rlr-nlines+1;
		end=cul;
		next=-1;
	} else if (nlines<0) {
		start=rul-nlines-1;
		end=rlr;
		next=1;
	} else {
		nlines=rlr-rul+1;
		goto filling;
	}
	do {
		start+=next;
		switch (curmode->memmodel) {
		case MTEXT:
		case CTEXT:		
			TEXT_CopyRow(curmode,cul,clr,start,start+nlines,base);break;
		case PLANAR4:		
			PLANAR4_CopyRow(curmode,cul,clr,start,start+nlines,base);break;

		}	
	} while (start!=end);
	/* Fill some lines */
filling:
	if (nlines>0) {
		start=rul;
	} else {
		nlines=-nlines;
		start=rlr-nlines+1;
	}
	for (;nlines>0;nlines--) {
		switch (curmode->memmodel) {
		case MTEXT:
		case CTEXT:		
			TEXT_FillRow(curmode,cul,clr,start,base,attr);break;
		case PLANAR4:		
			PLANAR4_FillRow(curmode,cul,clr,start,base,attr);break;
		}	
		start++;
	} 
}

void INT10_SetActivePage(Bit8u page) {

	Bit16u mem_address;
	Bit8u cur_col=0 ,cur_row=0 ;
	
	VGAMODES * curmode=GetCurrentMode();
	if (curmode==0) return;
	if (page>7) return;
	mem_address=page*curmode->slength;
	/* Write the new page start */
	real_writew(BIOSMEM_SEG,BIOSMEM_CURRENT_START,mem_address);
	if (curmode->svgamode<8) mem_address>>=1;


	/* Write the new start address in vgahardware */
	IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS),0x0c);
	IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS)+1,(mem_address&0xff00)>>8);
	IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS),0x0d);
	IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS)+1,mem_address&0x00ff);

	// And change the BIOS page
	real_writeb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE,page);

	// Display the cursor, now the page is active
	INT10_SetCursorPos(cur_row,cur_col,page);
}


void INT10_SetCursorPos(Bit8u row,Bit8u col,Bit8u page) {
	Bit16u address;

	if(page>7) return;
	// Bios cursor pos
	real_writeb(BIOSMEM_SEG,BIOSMEM_CURSOR_POS+page*2,col);
	real_writeb(BIOSMEM_SEG,BIOSMEM_CURSOR_POS+page*2+1,row);
	// Set the hardware cursor
	Bit8u current=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	if(page==current) {
		// Get the dimensions
		BIOS_NCOLS;BIOS_NROWS;
		// Calculate the address knowing nbcols nbrows and page num
		address=SCREEN_IO_START(ncols,nrows,page)+col+row*ncols;
		// CRTC regs 0x0e and 0x0f
		IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS),0x0e);
		IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS)+1,(address&0xff00)>>8);
		IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS),0x0f);
		IO_Write(real_readw(BIOSMEM_SEG,BIOSMEM_CRTC_ADDRESS)+1,address&0x00ff);
  }
}


void INT10_ReadCharAttr(Bit16u * result,Bit8u page) {

	if(page==0xFF) page=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	BIOS_NCOLS;BIOS_NROWS;
	Bit8u cur_row=CURSOR_POS_ROW(page);
	Bit8u cur_col=CURSOR_POS_COL(page);
 
	Bit16u address=SCREEN_MEM_START(ncols,nrows,page)+(cur_col+cur_row*ncols)*2;
	*result=real_readw(0xb800,address);
}



INLINE static void WriteChar(Bit16u col,Bit16u row,Bit8u page,Bit8u chr,Bit8u attr,bool useattr) {
	VGAMODES * curmode=GetCurrentMode();
	switch (curmode->type) {
	case TEXT:
		{	
			// Compute the address  
			Bit16u address=SCREEN_MEM_START(curmode->twidth,curmode->theight,page)+(col+row*curmode->twidth)*2;
			// Write the char 
			real_writeb(0xb800,address,chr);
			if (useattr) {
				real_writeb(0xb800,address+1,attr);
			}
		}
		break;
	case GRAPH:
		{
			/* Amount of lines */
			Bit8u * fontdata;
			Bit16u x,y;
			switch (curmode->cheight) {
			case 8:
//				fontdata=&int10_font_08[chr*8];
				if (chr<128) fontdata=Real2Host(RealGetVec(0x43))+chr*8;
				else fontdata=Real2Host(RealGetVec(0x1F))+(chr-128)*8;
				break;
			case 14:
				fontdata=&int10_font_14[chr*14];
				break;
			case 16:
				fontdata=&int10_font_16[chr*16];
				break;
			default:
				LOG_ERROR("INT10:Teletype Illegal Font Height");
				return;
			}
			x=8*col;
			y=curmode->cheight*row;
			//TODO Check for out of bounds
			for (Bit8u h=0;h<curmode->cheight;h++) {
				Bit8u bitsel=128;
				Bit8u bitline=*fontdata++;
				Bit16u tx=x;
				while (bitsel) {
					if (bitline&bitsel) INT10_PutPixel(tx,y,page,attr);
					else INT10_PutPixel(tx,y,page,0);
					tx++;
					bitsel>>=1;
				}
				y++;
			}
		}
		break;
	}
}




void INT10_WriteChar(Bit8u chr,Bit8u attr,Bit8u page,Bit16u count,bool showattr) {
	if(page==0xFF) page=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	Bit8u cur_row=CURSOR_POS_ROW(page);
	Bit8u cur_col=CURSOR_POS_COL(page);
	BIOS_NCOLS;BIOS_NROWS;
	while (count>0) {
		WriteChar(cur_col,cur_row,page,chr,attr,showattr);
		count--;
		cur_col++;
		if(cur_col==ncols) {
			cur_col=0;
			cur_row++;
		}
	}
}


void INT10_TeletypeOutput(Bit8u chr,Bit8u attr,bool showattr, Bit8u page) {
	if(page==0xFF) page=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	BIOS_NCOLS;BIOS_NROWS;
	Bit8u cur_row=CURSOR_POS_ROW(page);
	Bit8u cur_col=CURSOR_POS_COL(page);

	switch (chr) {
	case 7:
	//TODO BEEP
	break;
	case 8:
		if(cur_col>0) cur_col--;
		break;
	case '\r':
		cur_col=0;
		break;
	case '\n':
		cur_col=0;
		cur_row++;
		break;
	case '\t':
		do {
			INT10_TeletypeOutput(' ',attr,showattr,page);
			cur_row=CURSOR_POS_ROW(page);
			cur_col=CURSOR_POS_COL(page);
		} while(cur_col%8==0);
		break;
	default:
		/* Draw the actual Character */
		WriteChar(cur_col,cur_row,page,chr,attr,showattr);
		cur_col++;
	}
	if(cur_col==ncols) {
		cur_col=0;
		cur_row++;
	}
	// Do we need to scroll ?
	if(cur_row==nrows) {
		INT10_ScrollWindow(0,0,nrows-1,ncols-1,-1,0x07,page);
		cur_row--;
	}
 	// Set the cursor for the page
	INT10_SetCursorPos(cur_row,cur_col,page);
}

void INT10_WriteString(Bit8u row,Bit8u col,Bit8u flag,Bit8u attr,PhysPt string,Bit16u count,Bit8u page) {

	if(page==0xFF) page=real_readb(BIOSMEM_SEG,BIOSMEM_CURRENT_PAGE);
	BIOS_NCOLS;BIOS_NROWS;
	Bit8u cur_row=CURSOR_POS_ROW(page);
	Bit8u cur_col=CURSOR_POS_COL(page);
	
	// if row=0xff special case : use current cursor position
	if (row==0xff) {
		row=cur_row;
		col=cur_col;
	}

	INT10_SetCursorPos(row,col,page);
	while (count>0) {
		Bit8u chr=mem_readb(string);
		string++;
		if (flag&2) {
			attr=mem_readb(string);
			string++;
		}
		INT10_TeletypeOutput(chr,attr,true,page);
		count--;
	}
	if (flag & 1) {
		INT10_SetCursorPos(cur_row,cur_col,page);
	}
}