#! /bin/sh

# decogen - Generate deco.gs CSS grid system
# Copyright (C) 2011 Matous J. Fialka, <http://mjf.cz/>
# Released under the terms of The MIT License

DECO_GS_PRECISION=${DECO_GS_PRECISION:-'5'}
DECO_GS_COLUMNS=${DECO_GS_COLUMNS:-'16'}
DECO_GS_COLUMN_MARGINS=${DECO_GS_COLUMN_MARGINS:-'2.083333333333'}

DECO_GS_COLUMN_MARGINS=`
	echo "${DECO_GS_COLUMN_MARGINS} / 1.0" |
	bc -l |
	sed '
		s/^\./0./
		s/^\([^.]\+\..\{'$DECO_GS_PRECISION'\}\).*/\1/
	'
`

column_width=`
	echo "100 / $DECO_GS_COLUMNS" |
	bc -l |
	sed '
		s/^\./0./
		s/^\([^.]\+\..\{'$DECO_GS_PRECISION'\}\).*/\1/
	'
`

cell_width=`
	echo "$column_width - $DECO_GS_COLUMN_MARGINS" |
	bc -l |
	sed '
		s/^\./0./
		s/^\([^.]\+\..\{'$DECO_GS_PRECISION'\}\).*/\1/
	'
`

cat << eof
/**
 *	DECO.GS (CSS GRID SYSTEM)
 *	-------------------------------------------------------
 *
 *	Number of columns:	$DECO_GS_COLUMNS
 *	Column margin width:	$DECO_GS_COLUMN_MARGINS percent
 *	Cell width:		$cell_width percent
 *	Column width:		$column_width percent
 *
 */

div.row {			/* Single row class */
	float:left;
	position:relative;
	width:100%;
	display:block;
}

div.cell {			/* Single cell class */
	float:left;
	position:relative;
	left:100%;
}

/**
 *	Cell width classes formula:
 *
 *	div.width_<n> width = <column width> * <n> - <column margin>
 */

eof

for n in `seq 1 $DECO_GS_COLUMNS`
do
	width=`
		echo "$column_width * $n - $DECO_GS_COLUMN_MARGINS" |
		bc -l |
		sed '
			s/^\./0./
			s/^\([^.]\+\..\{'$DECO_GS_PRECISION'\}\).*/\1/
		'
	`
	sed 's/^\t//' << eof
	div.width-$n {
		width:${width}%;
	}

eof
done

cat << eof
/**
 *	Cell position classes formula:
 *
 *	div.position_<n> left margin = <column width> * n - 100
 */

eof

for n in `seq 1 $DECO_GS_COLUMNS`
do
	n=`
		echo "$n - 1" |
		bc -l
	`
	left_margin=`
		echo "$column_width * $n - 100" |
		bc -l |
		sed '
			s/^\./0./
			s/^\([^.]\+\..\{'$DECO_GS_PRECISION'\}\).*/\1/
		'
	`
	sed 's/^\t//' << eof
	div.position-$n {
		margin-left:${left_margin}%;
	}

eof
done

cat << eof
/**
 *	Example usage (for 16 columns):
 *
 *	<div class="row">
 *		<div class ="cell position_0 width_7">...</div>
 *		<div class ="cell position_4 width_1">...</div>
 *		<div class ="cell position_4 width_8">...</div>
 *	</div>
 *
 *	Generated by decogen `date '+on %F at %R'`.
 */
eof