/*	Copyright  (c)	Günter Woigk 2012 - 2017
					mailto:kio@little-bat.de

	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.

	Permission to use, copy, modify, distribute, and sell this software and
	its documentation for any purpose is hereby granted without fee, provided
	that the above copyright notice appear in all copies and that both that
	copyright notice and this permission notice appear in supporting
	documentation, and that the name of the copyright holder not be used
	in advertising or publicity pertaining to distribution of the software
	without specific, written prior permission.  The copyright holder makes no
	representations about the suitability of this software for any purpose.
	It is provided "as is" without express or implied warranty.

	THE COPYRIGHT HOLDER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
	INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
	EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY SPECIAL, INDIRECT OR
	CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
	DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
	TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
	PERFORMANCE OF THIS SOFTWARE.
*/

#include "kio/kio.h"
#include "SimpleTerminal.h"
#include <QFont>
#include <QChar>
#include <QPainter>
#include <QPixmap>
#include <QImage>
#include <QRect>


/*	TODO

	Cursor Blob
	Print Graphics Char

	col bei dbl_width
	row bei dbl_height

	Durch Rundung kann dbl_width ein pixel zu schmal (oder zu breit?) sein
*/



// ---------------------------------------------------------------------
// Creator

SimpleTerminal::SimpleTerminal(QWidget*p, QString fontname, int fontsize, bool antialias)
:	QWidget(p)
{
	xlogIn("new SimpleTerminal");

	canvas  = new QPixmap(width(),height()/*,QImage::Format_RGB32*/);
	painter = new QPainter(canvas);

	setFont(fontname,fontsize,antialias);
	reset();

	xlogline("FONT FAMILY = %s",font.family().toUtf8().data());

	xlogline("SimpleTerminal: pointsize = %i",pointsize);		// 12

	xlogline("SimpleTerminal: char_width  = %i",char_width);	// 7
	xlogline("SimpleTerminal: line_height = %i",line_height);	// 16
	xlogline("SimpleTerminal: ascent  = %i",ascent);			// 12
	xlogline("SimpleTerminal: descent = %i",descent);			// 2
	xlogline("SimpleTerminal: height  = %i",char_height);		// 15
	xlogline("SimpleTerminal: leading = %i",leading);			// 1

	xlogline("SimpleTerminal: width  = %i",width());			// 100
	xlogline("SimpleTerminal: height = %i",height());			// 30
}

SimpleTerminal::~SimpleTerminal()
{
	delete painter;
	delete canvas;
}


// ---------------------------------------------------------------------
// Settings:

void SimpleTerminal::reset()
{
	pushed_paper = paper = Qt::white;
	pushed_pen   = pen	 = Qt::black;
	clear_color	 =         Qt::white;
	pushed_attr  = 0;

	attr = 0xff;
	clearAllAttributes();
	clearScreen();
}


void SimpleTerminal::set_colors()	// Helper
{
	painter->setBackgroundMode(attr&OVERPRINT ? Qt::TransparentMode : Qt::OpaqueMode);

	if(attr&INVERTED) { painter->setPen(paper); painter->setBackground(pen); painter->setBrush(pen); }
	else		      { painter->setPen(pen); painter->setBackground(paper); painter->setBrush(paper);}
}


void SimpleTerminal::setFont(QString fontname, int size, bool antialias)
{
	xlogIn("SimpleTerminal::setFont: %s",fontname.toUtf8().data());

	font = QFont(fontname,size);
	font.setFixedPitch(true);
	font.setStyleStrategy(antialias ? QFont::ForceIntegerMetrics : (QFont::StyleStrategy)(QFont::ForceIntegerMetrics|QFont::NoAntialias));
	pointsize = font.pointSize();

	painter->setFont(font);
	QFontMetrics m = painter->fontMetrics();
	char_width  = m.averageCharWidth();
	line_height = m.lineSpacing();
	ascent = m.ascent();
	descent = m.descent();
	char_height = m.height();
	leading = m.leading();

	cols = (width()+1)/char_width;
	rows = (height()+leading)/line_height;

	attr = 0;
	set_colors();
}


void SimpleTerminal::setAttributesTo(uint a)
{
	if(a==attr) return;
	attr = a;

	font.setUnderline(a&UNDERLINE);
	font.setBold(a&BOLD);
	font.setItalic(a&ITALIC);

	if(a&DOUBLE_HEIGHT)
	{
		font.setPointSize(pointsize*2);
		font.setStretch(a&DOUBLE_WIDTH ? QFont::Unstretched : QFont::UltraCondensed);
	}
	else
	{
		font.setPointSize(pointsize);
		font.setStretch(a&DOUBLE_WIDTH ? QFont::UltraExpanded : QFont::Unstretched);
		//logline("XXX average char width = %i",painter->fontMetrics().averageCharWidth());
	}
	painter->setFont(font);

	set_colors();
}


void SimpleTerminal::setPaperColor(QColor c)
{
	paper = c;
	set_colors();
}


void SimpleTerminal::setPenColor(QColor c)
{
	pen = c;
	set_colors();
}


void SimpleTerminal::pushCursor()
{
	pushed_row   = row;
	pushed_col   = col;
	pushed_attr  = attr;
	pushed_paper = paper;
	pushed_pen   = pen;
	pushed_blob  = blob;
}


void SimpleTerminal::popCursor()
{
	row   = pushed_row;
	col   = pushed_col;
	attr  = pushed_attr;
	paper = pushed_paper;
	pen   = pushed_pen;
	blob  = pushed_blob;

	setAttributesTo(attr);
}


// ---------------------------------------------------------------------
// Move Cursor:


/*	Zwinge 'col' in den Bereich [0 ... cols]
*/
void SimpleTerminal::handle_h_overflow()
{
	while(col<0)	{ col+=cols; row-=1; }
	while(col>cols) { col-=cols; row+=1; }
}


/*	Zwinge 'row' in den Bereich [0 ... rows-1]
*/
void SimpleTerminal::handle_v_overflow()
{
	if(row>=rows)  scrollScreen(row-rows+1);
	else if(row<0) scrollScreen(row);
}


/*	Remove the cursor blob; if visible
	Zwinge 'col' in den Bereich [0 ... cols-1]
	und 'row' in den Bereich [0 ... rows-1]
	so dass mindestens ein Zeichen oder der Blob gedruckt werden können
*/
void SimpleTerminal::hideBlob()
{
	if(blob)
	{
		//TODO
		blob = off;
	}
	else
	{
		if((uint16)col>(uint16)cols)  handle_h_overflow();
		if(col==cols)			      { col=0; row++; }
		if((uint16)row>=(uint16)rows) handle_v_overflow();
	}
}


/*	Show cursor blob
	Zwinge 'col' in den Bereich [0 ... cols-1]
	und 'row' in den Bereich [0 ... rows-1]
	so dass mindestens ein Zeichen oder der Blob gedruckt werden können
*/
void SimpleTerminal::showBlob()
{
	if(!blob)
	{
		if((uint16)col>(uint16)cols)  handle_h_overflow();
		if(col==cols)                 { col=0; row++; }
		if((uint16)row>=(uint16)rows) handle_v_overflow();
		//TODO();
		blob = on;
	}
}


void SimpleTerminal::moveTo(int row,int col)
{
	if(blob) hideBlob();
	this->row = (int16)row;
	this->col = (int16)col;
}

void SimpleTerminal::moveToColumn(int col)
{
	if(blob) hideBlob();
	this->col = (int16)col;
}

void SimpleTerminal::cursorLeft(int n)
{
	if(blob) hideBlob();
	col -= (int16)n;
}

void SimpleTerminal::cursorRight(int n)
{
	if(blob) hideBlob();
	col += (int16)n;
}

void SimpleTerminal::cursorUp(int n)
{
	if(blob) hideBlob();
	row -= (int16)n;
}

void SimpleTerminal::cursorDown(int n)
{
	if(blob) hideBlob();
	row += (int16)n;
}

void SimpleTerminal::cursorReturn()
{
	if(blob) hideBlob();
	col = 0;
}

void SimpleTerminal::cursorTab(int n)
{
	if(blob) hideBlob();
	col = ((int16)col/8+n)*8;
}


// ----------------------------------------------------------
// Clear, scroll, copy:

void SimpleTerminal::clearScreen()
{
	canvas->fill(clear_color);
	row = col = 0;
	pushed_blob = blob = off;
	update();
}


void SimpleTerminal::clearRect(int rows, int cols)
{
	if(blob) hideBlob();

	rows = min(rows,this->rows-row);
	cols = min(cols,this->cols-col);

	if(rows>0 && cols>0)
	{
		painter->fillRect(col*char_width, row*line_height, cols*char_width, rows*line_height, clear_color);
		update(col*char_width, row*line_height, cols*char_width, rows*line_height);
	}
}

void SimpleTerminal::clearToEndOfLine()
{
	if(blob) hideBlob();

	if((uint)row<(uint)rows && (uint)col<(uint)cols)
	{
		painter->fillRect(col*char_width, row*line_height, (cols-col)*char_width, line_height, clear_color);
		update(col*char_width, row*line_height, (cols-col)*char_width, line_height);
	}
}


/*	Scroll screen up (n>0) or down (n<0)
	takes care for cursor position and blob
*/
void SimpleTerminal::scrollScreen(int n)
{
	if(n>0)		// up
	{
		n = min(n,rows);
		QPixmap z = canvas->copy(0, n*line_height, width(), (rows-n)*line_height);
		painter->drawPixmap(QPoint(0,0),z);
		painter->fillRect(0, (rows-n)*line_height, width(), n*line_height, clear_color);
		row -= n;        if(row<0)        blob = off;
		pushed_row -= n; if(pushed_row<0) pushed_blob = off;
		update();
	}
	else if(n<0)	// down
	{
		n = min(-n,rows);
		QPixmap z = canvas->copy(0, 0, width(), (rows-n)*line_height);
		painter->drawPixmap(QPoint(0,n*line_height),z);
		painter->fillRect(0, 0, width(), n*line_height, clear_color);
		row += n;		if(row>=rows) blob = off;
		pushed_row +=n;	if(pushed_row>=rows) pushed_blob = off;
		update();
	}
}


/*	copy r with size rows * cols from current cursor position to destination position z
*/
void SimpleTerminal::copyRect(int z_row, int z_col, int z_rows, int z_cols)
{
	if(blob) hideBlob();

	z_rows = min(z_rows,rows-row); z_rows = min(z_rows,rows-z_row);
	z_cols = min(z_cols,cols-col); z_cols = min(z_cols,cols-z_col);

	if(z_rows>0 && z_cols>0)
	{
		QPixmap z = canvas->copy(col*char_width, row*line_height, z_cols*char_width, z_rows*line_height);
		painter->drawPixmap(QPoint(z_col*char_width,z_row*line_height),z);
		update(z_col*char_width,z_row*line_height,z_cols*char_width, z_rows*line_height);
	}
}


// ----------------------------------------------------------
// Print:

void SimpleTerminal::draw_text(QString s)
{
	int x = col*char_width;
	int y = row*line_height;
	int n = s.length();

	painter->drawText(x, y+ascent, s);

	if(leading && (~attr&OVERPRINT))
	{
		painter->setPen(Qt::NoPen);
		//painter->setBrush(paper);
		painter->drawRect(x,y+char_height,n*char_width,leading);
		painter->setPen(attr&INVERTED?paper:pen);
	}

	update(x,y,n*char_width,line_height);

	col += n;
}

void SimpleTerminal::print(QChar c, int n)
{
	hideBlob();		// and force inside
	n = (int16)n;	// security

	if(n==1)	 draw_text(QString(c));
	else if(n>1) print(QString(n,c));
}

void SimpleTerminal::print(QString s, int n)
{
	hideBlob();		// and force inside
	n = (int16)n;	// security

	if(n==1)
	{
		while(s.length()>cols-col)
		{
			n = cols-col;
			draw_text(s.left(n));
			s = s.mid(n);
			col = 0; row++;
			hideBlob();
		}

		draw_text(s);
	}
	else if(n>1)
	{
		if(s.length()<cols) { print(s+s,n/2); if(n&1) print(s,1); }
		else while(n) print(s,n--);
	}
}


void SimpleTerminal::printAt(int row, int col, QString s, int n)
{
	moveTo(row,col);
	print(s,n);
}

void SimpleTerminal::printAt(int row, int col, QChar c, int n)
{
	moveTo(row,col);
	print(c,n);
}


void SimpleTerminal::printGraphicsCharacter(uint16 bmp[], int n)
{
	TODO();
	(void)bmp; (void)n;
}






void SimpleTerminal::paintEvent(QPaintEvent*)		 // virtual protected
{
	QPainter painter(this);
	painter.drawPixmap(0,0,*canvas);

	if(hasFocus())
	{
		QPen pen(QColor(0x88,0xff,0x00,0x88));
		pen.setWidth(6);
		painter.setPen(pen);
		painter.setCompositionMode(QPainter::CompositionMode_Darken);
		painter.drawRect(rect());
	}
}


void SimpleTerminal::resizeEvent(QResizeEvent*)		 // virtual protected
{
	xlogIn("SimpleTerminal::resizeEvent(w=%i,h=%i)",width(),height());

	rows = height()/line_height;
	cols = width()/char_width;

	if(canvas->width()<width()||canvas->height()<height())
	{
		int w = max(canvas->width(),width());
		int h = max(canvas->height(),height());
		QPixmap p = canvas->copy();
		painter->end();
		delete canvas;
		canvas = new QPixmap(w+char_width,h+line_height/*,QImage::Format_RGB32*/);
		painter->begin(canvas);
		canvas->fill(clear_color);
		painter->drawPixmap(0,0,p);
		painter->setFont(font);		// gets reset by begin()
		set_colors();				// get reset by begin()
	}
	emit resized();
}


void SimpleTerminal::focusInEvent	(QFocusEvent*e)
{
	QWidget::focusInEvent(e);
	emit focusChanged(1);
}

void SimpleTerminal::focusOutEvent	(QFocusEvent* e)
{
	QWidget::focusOutEvent(e);
	emit focusChanged(0);
}