#!/bin/sh
#TODO command line arguments processing (--help)
tmp_ddcprobe_output=$1
if [ -z $tmp_ddcprobe_output ]; then
    tmp_ddcprobe_output=/tmp/ddcprobe_output
    ddcprobe > ${tmp_ddcprobe_output} 
fi
failed=`sed -n '/edid.*failed/Ip' ${tmp_ddcprobe_output}`
if [ -n "$failed" ]; then
    echo "Error: Display seems to be incapable of providing DDC Information"
    echo 'Recommended Screen Modes: "1024x768" "800x600" "640x480"'
    exit 1;
fi
screen_size_in_qcm=$((`sed -n "s/[Ss]creen.*[Ss]ize[^0-9]*\([0-9]*\)[^0-9]*\([0-9]*\).*/\1 *  \2/p" ${tmp_ddcprobe_output}`))
max_pixels=$((`echo "\`sed -n '/edid/I,$s/.*[ \t]\([0-9]\{3,4\}\)x\([0-9]\{3,4\}\).*/\2 * \1/p' ${tmp_ddcprobe_output}|sort -rn| sed -n 1p\`"`))
manufacturing_year=`sed -n 's/manufact.*\([12][90][0-9][0-9]\).*/\1/Ip' ${tmp_ddcprobe_output}`

if [ -z $screen_size_in_qcm ] || [ -z $manufacturing_year ] || [ -z $max_pixels ] ; then
    echo "Error: Display seems to be incapable of providing all relevant DDC Information"
    echo 'Recommended Screen Modes: "1024x768" "800x600" "640x480"'
    exit 1;
fi

pix_per_qcm=$(($max_pixels/$screen_size_in_qcm))
echo "Display size:	$screen_size_in_qcm qcm"
echo "Max Pixels per qcm:	$pix_per_qcm"
echo "Manufacturing year:	$manufacturing_year"
# Set probability for having an LCD by means of age and size
# 15" ~ 30.6cm x 23cm
# 17" ~ 34cm x 27cm (17,1")
# 19" ~ 38,6cm x 29cm
# if older than 1998 it is most probably not a LCD
if [ $manufacturing_year -lt 1998 ] ;then tft_probability=1
# if older than 2002 is probably no LCD, especially if larger than 15"
elif [ $manufacturing_year -lt 2002 ];then 
    if [ $screen_size_in_qcm -gt 704 ]; then tft_probability=1
    else tft_probability=20
    fi
# if older than 2003 is maybe no LCD, yet for sure if larger than 17"
elif [ $manufacturing_year -lt 2003 ];then 
    if [ $screen_size_in_qcm -gt 918 ]; then tft_probability=5
    else tft_probability=40
    fi
# if older than 2005 is probable an LCD, but not if larger than 19"
elif [ $manufacturing_year -lt 2005 ];then 
    if [ $screen_size_in_qcm -gt 1121 ]; then tft_probability=10
    else tft_probability=60
    fi
# in 2005 few people would buy a (new) CRT
elif [ $manufacturing_year -lt 2006 ];then tft_probability=90 
# after 2006 nobody would buy a new CRT
else tft_probability=99
fi
if [ $pix_per_qcm -gt 1599 ]; then tft_probability=$(($tft_probability - 15))
else tft_probability=$(($tft_probability + 15))
fi
echo -ne "Is a TFT:\t"
if [ $tft_probability -ge 50 ]; then
    echo -n "true"
else echo -n "false"
fi
echo " ($tft_probability)"

# Find the lines with two times 3 to 4 digits delimited by an x. Print with the two values reverted, so sort sorts w.r.t the 2nd value. Then swap back
screen_resolutions=`sed -n '/edid/I,$s/.*[ \t]\([0-9]\{3,4\}\) *x *\([0-9]\{3,4\}\).*/\2 x \1/p' ${tmp_ddcprobe_output}| sort -rn | sort -rnu | sed -n 's/\([0-9]\{3,4\}\) x \([0-9]\{3,4\}\).*/"\2x\1"/p' `
screen_resolutions=`echo $screen_resolutions`
echo "Supported Screen Modes: $screen_resolutions"

# For CRTs check if the highest frequency can be displayed with reasonable refresh rate (> 80Hz)
if [ $tft_probability -lt 50 ]; then
    highest_resolution=` echo $screen_resolutions | sed -n 's/"\([0-9x]*\)" .*/\1/p'`
    #echo $highest_resolution
    #Search for an @ in the same line as the highest resolution
    freq_for_highest_res=`sed -n /$highest_resolution'/s/[^@]*@\([0-9]\{2,3\}\).*/\1/p' $tmp_ddcprobe_output | sort -nr|sed -n 1p`
    #echo $freq_for_highest_res
    if [ -z "$freq_for_highest_res" ]; then
        #Search for a number followed by the term "Hz" in the same line as the highest resolution
	freq_for_highest_res=`sed -n /$highest_resolution'/s/.*[^a-zA-Z0-9]\([0-9]\{2,3\}\)[ \t]*[Hh][Zz].*/\1/p' $tmp_ddcprobe_output | sort -nr|sed -n 1p`
    fi
    # Assure that the highest resolution is removed if we do not know at what refresh rate it is displayed
    # Chances are it would be flickering at that resolution
    if [ -z "$freq_for_highest_res" ]; then 
        freq_for_highest_res=0
    fi
    if [ $freq_for_highest_res -lt 80 ]; then
        screen_resolutions=` echo $screen_resolutions | sed -n 's/"[0-9x]*" \(.*\)/\1/p'`
    fi
fi
echo "Recommended Screen Modes: $screen_resolutions"