#!/usr/bin/env bash

# Constants
readonly TRUE=0;

# Variables
APP_ICON="emblem-photos";
APP_NAME="$(basename $0)";
FILE_NAME="$HOME/$(date +%F_%H%M%S).png";
LANG="${LANGUAGE#*:}";
BORDER_SIZE="20"; #px
SCRIPT_DEPS=(
    xdpyinfo
    import
    awk
    sed
);

# Check script dependencies
function require () {
    local NF;
    while (($#)); do
        test -z $(which $1 2> /dev/null) && NF+=("$1");
        shift;
    done

    # Return the elements of array what have been not found
    test ${#NF[@]} -ne 0 && {
        echo ${NF[@]} && return 1;
    }

    return 0;
}

# Show message
function message () {
    MESSAGE="$@";
    notify-send -t 10000 -i $APP_ICON "$APP_NAME" "$MESSAGE" &> /dev/null \
    || echo -e "$@" 1>&2;
}

# Getting of selected area size
function getAreaSize () {
    AREA=( $(
            import -verbose /dev/null 2>&1 \
            | sed 's/.*PS.\(.*\)[0-9][0-9]-.*/\1/g;s/[x+]/ /g' \
            | awk '{print $1" "$2" "$5" "$6}';
        )
    )

    # is fail?
    test ${#AREA[@]} -ne 4 && return 2;

    # is success?
    # Return points array (x2-x1, y2-y1, x1, y1)
    echo ${AREA[@]};

    return 0;
}

# Increase rectangle size
function increaseRect () {
    # FIXME: Complete this function :)

    local POINTS=($@);
    local x1=${POINTS[2]};
    local y1=${POINTS[3]};
    local x2=$(( ${POINTS[2]} + ${POINTS[0]} ));
    local y2=$(( ${POINTS[3]} + ${POINTS[1]} ));

    for i in ${#POINTS[@]}; do
        local DONE=0;
        xdpyinfo -ext XINERAMA | sed '/^  head #/!d;s///' |
        while IFS=' :x@,' read i w h x y; do
            case $i in
            0)
                
            ;;
            1)
            ;;
            2)
            ;;
            3)
            ;;
            esac

            #echo -e "x=$x\ny=$y\nwidth=$w\nheight=$h";
            # test $DONE -eq 1 || { return 3 }
            DONE=1;
        done
    done
    return $DONE;
}

# Make screenshot
function makeScreenshot () {
    local POINTS=($@);
    local ANY_WARNINGS=$(
        import -window root \
        -crop "${POINTS[0]}x${POINTS[1]}+${POINTS[2]}+${POINTS[3]}" \
        "$FILE_NAME" 2>&1 | awk -F':|@' '{print $2}';
    );

    test -z "$ANY_WARNINGS" || {
        echo $ANY_WARNINGS;
        return 3;
    }

    return 0;
}

### Check script dependency
NOT_FOUND=( $(require "${SCRIPT_DEPS[@]}") );
test ${PIPESTATUS[0]} -eq $TRUE || {
    message "ERROR: Unresolved dependencies:\n$(printf '%s\n' ${NOT_FOUND[@]})";
    exit 1;
}

### Try to get area size
SELECTED=( $(getAreaSize) );
test ${PIPESTATUS[0]} -eq $TRUE || {
    message "ERROR: Can't get area size";
    exit 2;
}

# TODO: uncomment this block when increaseRect works fine
### Make screenshot
##WARNING="$(makeScreenshot ${SELECTED[@]})";
##test ${PIPESTATUS[0]} -eq $TRUE || {
##    message "ERROR: $WARNING";
##    exit 3;
##}

increaseRect ${SELECTED[@]};
message "Screenshot successfully created:\n$FILE_NAME";

exit 0;