#!/bin/bash
# Compile a pattern generator and dump output to stdout.
#
# Requires ImageMagick and terminal with sixel support.  Terminals that
# support sixel include xterm when launched with "xterm -ti vt340",
# and also Cygwin's mintty.

if [[ $# -ne 1 ]]; then
   echo "$0 <pattern_generator.c>"
   exit 1
fi
if ! [[ -r $1 ]]; then
   echo "$1 is not readable"
   exit 1
fi

# Build target and sizing utility.
target=${1%.c}.exe
make -j -s terminal_size.exe $target || exit 1

# Set output image size.
terminal_width=$(./terminal_size.exe ws_xpixel)
terminal_height=$(./terminal_size.exe ws_ypixel)
if [[ $terminal_width -gt 0 ]] && [[ $terminal_height -gt 0 ]]; then
   # Successfully gotten terminal size in pixels.  Now try adding some margins.
   columns=$(./terminal_size.exe ws_col)
   rows=$(./terminal_size.exe ws_row)
   font_width=$(( $terminal_width / $columns ))
   font_height=$(( $terminal_height / $rows ))

   width=$(( $font_width * ($columns - 1) ))
   height=$(( $font_height * ($rows - 2) ))
else
   # Couldn't get terminal size in pixels, assume a specific font size
   # and go with that.
   font_width=8
   font_height=18
   terminal_width=$(( $(tput cols) * $font_width ))
   terminal_height=$(( $(tput lines) * $font_height ))

   width=$(( $terminal_width / $(tput cols) * ($(tput cols) - 1) ))
   height=$(( $terminal_height / $(tput lines) * ($(tput lines) - 2) ))
fi

# Run and feed output through ImageMagick.
./$target $width $height 2>/dev/null | convert ppm:- six:-