diff --git a/cdscript.sh b/cdscript.sh
index 0dcb5f0..1ee0b05 100644
--- a/cdscript.sh
+++ b/cdscript.sh
@@ -1,147 +1,310 @@
 #!/usr/bin/env bash
-#      this title font is insanely over the top for what this does
-#  ▄████▄  ▓█████▄      ██████  ▄████▄   ██▀███   ██▓ ██▓███  ▄▄▄█████▓
-# ▒██▀ ▀█  ▒██▀ ██▌   ▒██    ▒ ▒██▀ ▀█  ▓██ ▒ ██▒▓██▒▓██░  ██▒▓  ██▒ ▓▒
-# ▒▓█    ▄ ░██   █▌   ░ ▓██▄   ▒▓█    ▄ ▓██ ░▄█ ▒▒██▒▓██░ ██▓▒▒ ▓██░ ▒░
-# ▒▓▓▄ ▄██▒░▓█▄   ▌     ▒   ██▒▒▓▓▄ ▄██▒▒██▀▀█▄  ░██░▒██▄█▓▒ ▒░ ▓██▓ ░ 
-# ▒ ▓███▀ ░░▒████▓    ▒██████▒▒▒ ▓███▀ ░░██▓ ▒██▒░██░▒██▒ ░  ░  ▒██▒ ░ 
-# ░ ░▒ ▒  ░ ▒▒▓  ▒    ▒ ▒▓▒ ▒ ░░ ░▒ ▒  ░░ ▒▓ ░▒▓░░▓  ▒▓▒░ ░  ░  ▒ ░░   
-#   ░  ▒    ░ ▒  ▒    ░ ░▒  ░ ░  ░  ▒     ░▒ ░ ▒░ ▒ ░░▒ ░         ░    
-# ░         ░ ░  ░    ░  ░  ░  ░          ░░   ░  ▒ ░░░         ░      
-# ░ ░         ░             ░  ░ ░         ░      ░                    
-# ░         ░                  ░                                       
+#         __                       __         __   
+# .----.--|  |    .-----.----.----.|__|.-----.|  |_ 
+# |  __|  _  |    |__ --|  __|   _||  ||  _  ||   _|
+# |____|_____|    |_____|____|__|  |__||   __||____|
+#                                      |__|                  
 #
-#               script to make cd jewel case inserts easily
-#               by sun                   https://sx7n8.tech/
-#
-#               dependencies are:
-#               imagemagick, bash
+#    script to make cd jewel case inserts easily    
+#    by sun                  https://sx7n8.tech/    
+#                                                   
+#    dependencies are:    imagemagick, bash, awk    
+
+# TODO:
+# - !!! Add support for back insert !!! 
+# - Remove bugs
+# - Add more paper types
+# - Make DPI a command line option
+# - Add different folding points for inserts
+# - Clean up code and add more comments
+# - Improve input and output further
 
-# TODO: add super jewel box and "digipack"
-# TODO: make code good
 
+# usage message
+USAGE="Usage: $0 -p <paper> -c <cover> -b <back> [-i <back_image>] [-m <border>] -o <output>"
 
-# general info 
-# EXT="jpg" # DO NOT CHANGE THIS TO PNG
-# TMP="/tmp"
-# NAME=work."$EXT" 
-# rm -f "$OUTPUT"
 
+# help message
+HELP="Script to create printable CD jewel case inserts
 
-# message that gets printed if theres missing or unexistant arguments
-USAGE="Usage: $0 [OPTIONS] [OUTPUT]\nTry '$0 -h' for more information" 
+Usage:
+  $0 -p <paper> -c <cover> -b <back> [-i <back_image>] [-m <border>] -o <output>
 
+Required options:
+  -p  Paper format            a4 | letter
+  -c  Album cover path        Path to cover image 
+  -b  Back type               no | image
+  -o  Output file             Path to save the resulting insert (NO PNG)
 
-# help message
-HELP="Script to create printable CD jewel case inserts 
-Options:
-
- flags                                           extra options
- -------------------------------------------------------------
- -h: shows this message and exits                         none
- -p: sets paper format  (necessary)                  a4|letter
- -c: sets the album cover path (necessary)              <path>
- -b: sets the back info (necessary)                   no|image
- -i: sets the back image (nec. is b = image)            <path>
- -m: sets a border around everything                 width(px)
- -o: sets output file (necessary)                       <path>
-
-!! DO NOT USE PNG !!
+Optional options:
+  -i  Back image path         Required if back type is 'image'
+  -m  Border width (px)       Adds a border around the cover/back
+
+DO NOT USE PNG FOR OUTPUT
 "
 
-###########################################
-### TODO: make the code and io not suck ###
-###########################################
+
+# error function
+error() {
+    echo -e "Error: $1" >&2
+    echo -e "$USAGE" >&2
+    exit 1
+}
+
+
+# file existance check
+check_file_exists() {
+    if [ ! -f "$1" ]; then
+        error "File '$1' does not exist."
+    fi
+}
+
+
+# file existance check but opposite
+check_output_file() {
+    if [ -f "$1" ]; then
+        error "Output file '$1' already exists."
+    fi
+}
+
 
 # getops argument handling
 while getopts "hp:c:b:i:m:o:" o; do
     case "${o}" in
         h)
-         echo -e "$HELP"
-         exit
+            echo -e "$HELP"
+            exit
+        ;;
+        p)
+            if [[ "$OPTARG" != "a4" && "$OPTARG" != "letter" ]]; then
+                error "Invalid paper type '$OPTARG'. Must be 'a4' or 'letter'."
+            fi
+            PAPER="$OPTARG"
         ;;
-
-	    p)
-	     if [[ "$OPTARG" = "a4" || "$OPTARG" = "letter" ]]; then 
-	      PAPER="$OPTARG"
-	     else 
-          echo "Invalid paper type. Run '$0 -h' for info."
-	     exit 1
-	     fi
-	    ;;
-
         c)
-         if [ -f "$OPTARG" ]; then
-          COVER="$OPTARG"
-          COVERSIZE="$(identify -format "%w" "$COVER")"
-         else 
-          echo "Invalid file. Run '$0 -h' for info."
-          exit 1
-         fi 
+            check_file_exists "$OPTARG"
+            COVER="$OPTARG"
+            COVERSIZE="$(identify -format "%w" "$COVER")"
         ;;
-
         b)
-         if [[ "$OPTARG" = "no" || "$OPTARG" = "image" ]]; then
-          BACKTYPE=$OPTARG
-         else
-          echo "Invalid back type. Run '$0 -h' for info."
-	      exit 1
-         fi
+            if [[ "$OPTARG" != "no" && "$OPTARG" != "image" ]]; then
+                error "Invalid back type '$OPTARG'. Must be 'no' or 'image'."
+            fi
+            BACKTYPE="$OPTARG"
         ;;
-
         i)
-        if [[ "$BACKTYPE" = "image" ]]; then
-          BACKIMG="$OPTARG"
-         else
-          echo "Invalid back type. Run '$0 -h' for info."
-	      exit 1
-         fi
-         if [ -f "$OPTARG" ]; then
-          :
-         else
-          echo "Invalid file. Run '$0 -h' for info."
-          exit 1
-         fi
+            if [[ "$BACKTYPE" != "image" ]]; then
+                error "-i option requires back type to be 'image'."
+            fi
+            check_file_exists "$OPTARG"
+            BACKIMG="$OPTARG"
         ;;
-
         m)
-         BORDER="TRUE"
-         BORDER_WIDTH="$OPTARG"
+            BORDER="TRUE"
+            BORDER_WIDTH="$OPTARG"
         ;;
-
         o)
-         if [ -f "$OPTARG" ]; then
-          echo -e "Error: file already exists."
-          exit 1
-         else
-          OUTPUT="$OPTARG"
-         fi
+            check_output_file "$OPTARG"
+            OUTPUT="$OPTARG"
         ;;
-
         *)
-         echo -e "$USAGE"
-         exit
+            echo -e "$USAGE"
+            exit 1
         ;;
     esac
 done
 
 
 # check if something is missing
-if [ -z "$PAPER" ] || [ -z "$COVER" ] || [ -z "$BACKTYPE" ] || [ -z "$OUTPUT" ]; then
-    echo -e "Error: missing options"
-    echo -e "$USAGE"
-    exit 1
+[[ -z "$PAPER" ]] && error "Missing paper format (-p)."
+[[ -z "$COVER" ]] && error "Missing cover image (-c)."
+[[ -z "$BACKTYPE" ]] && error "Missing back type (-b)."
+[[ -z "$OUTPUT" ]] && error "Missing output file (-o)."
+[[ "$BACKTYPE" == "image" && -z "$BACKIMG" ]] && error "Missing back image (-i) for back type 'image'."
+
+
+# function to convert mm to px with dpi
+CONVERT() { awk -v mm="$1" -v dpi="$2" 'BEGIN{printf("%d", mm/25.4*dpi + 0.5)}'; }
+
+
+# DPI of paper
+DPI="300"
+
+
+# cover art size (mm)
+CO_MM="120"
+CO_PX="$(CONVERT "$CO_MM" "$DPI")"
+
+
+# Width and Height of paper in mm
+A4MM_W="210"
+A4MM_H="297"
+
+LTMM_W="216"
+LTMM_H="279"
+
+
+# same values in pixels
+A4PX="$(CONVERT "$A4MM_W" "$DPI")x$(CONVERT "$A4MM_H" "$DPI")"
+LTPX="$(CONVERT "$LTMM_W" "$DPI")x$(CONVERT "$LTMM_H" "$DPI")"
+
+
+# assign to the 'size' variable the right value
+if [ "$PAPER" = "a4" ]; then
+    SIZE=$A4PX
+elif [ "$PAPER" = "letter" ]; then  
+    SIZE=$LTPX
+else 
+    echo "what the fuck did you do"
+    exit
 fi
 
 
-# check if i is missing
-if [[ "$BACKTYPE" == "image" && -z "$BACKIMG" ]]; then
-    echo -e "Error: missing options"
-    echo -e "$USAGE"
-    exit 1
+# create a blank file with the specified paper type
+magick -colorspace sRGB -type TrueColor -depth 8 -size $SIZE canvas:white "$OUTPUT" > /dev/null
+
+
+# draws border (rectangle)
+if [ "$BORDER" = "TRUE" ]; then
+INSET=$((BORDER_WIDTH / 2))
+magick ""$OUTPUT"" \( -size $((CO_PX + 2 * BORDER_WIDTH))x$((CO_PX * 2 + 2 * BORDER_WIDTH)) xc:none -colorspace sRGB -type TrueColor -depth 8 -fill none -stroke black -strokewidth $BORDER_WIDTH -draw "rectangle $INSET,$INSET $((CO_PX + BORDER_WIDTH - 1)),$((CO_PX * 2 + BORDER_WIDTH - 1))" \) -gravity center -composite ""$OUTPUT""
 fi
 
 
+# add the cover art set to the right size, rotated left by 90d and shifted up by (cover art size) / 2
+magick -colorspace sRGB -type TrueColor -depth 8 "$OUTPUT" \( "$COVER" -resize ${CO_PX}x${CO_PX} -rotate 270 \) -gravity center -geometry +0-$((CO_PX/2)) -composite "$OUTPUT" > /dev/null
+
+
+# adds back
+if [ "$BACKTYPE" = "image" ]; then
+magick -colorspace sRGB -type TrueColor -depth 8 "$OUTPUT" \( "$BACKIMG" -resize ${CO_PX}x${CO_PX} -rotate 270 \) -gravity center -geometry +0+$((CO_PX/2)) -composite "$OUTPUT" > /dev/null
+else
+magick -colorspace sRGB -type TrueColor -depth 8 "$OUTPUT" \( -size ${CO_PX}x${CO_PX} xc:'#FFFFFF' \) -gravity center -geometry +0+$((CO_PX/2)) -composite "$OUTPUT" > /dev/null
+fi#!/usr/bin/env bash
+#         __                       __         __   
+# .----.--|  |    .-----.----.----.|__|.-----.|  |_ 
+# |  __|  _  |    |__ --|  __|   _||  ||  _  ||   _|
+# |____|_____|    |_____|____|__|  |__||   __||____|
+#                                      |__|                  
+#
+#    script to make cd jewel case inserts easily    
+#    by sun                  https://sx7n8.tech/    
+#                                                   
+#    dependencies are:    imagemagick, bash, awk    
+
+# TODO:
+# - !!! Add support for back insert !!! 
+# - Remove bugs
+# - Add more paper types
+# - Make DPI a command line option
+# - Add different folding points for inserts
+# - Clean up code and add more comments
+# - Improve input and output further
+
+
+# usage message
+USAGE="Usage: $0 -p <paper> -c <cover> -b <back> [-i <back_image>] [-m <border>] -o <output>"
+
+
+# help message
+HELP="Script to create printable CD jewel case inserts
+
+Usage:
+  $0 -p <paper> -c <cover> -b <back> [-i <back_image>] [-m <border>] -o <output>
+
+Required options:
+  -p  Paper format            a4 | letter
+  -c  Album cover path        Path to cover image 
+  -b  Back type               no | image
+  -o  Output file             Path to save the resulting insert (NO PNG)
+
+Optional options:
+  -i  Back image path         Required if back type is 'image'
+  -m  Border width (px)       Adds a border around the cover/back
+
+DO NOT USE PNG FOR OUTPUT
+"
+
+
+# error function
+error() {
+    echo -e "Error: $1" >&2
+    echo -e "$USAGE" >&2
+    exit 1
+}
+
+
+# file existance check
+check_file_exists() {
+    if [ ! -f "$1" ]; then
+        error "File '$1' does not exist."
+    fi
+}
+
+
+# file existance check but opposite
+check_output_file() {
+    if [ -f "$1" ]; then
+        error "Output file '$1' already exists."
+    fi
+}
+
+
+# getops argument handling
+while getopts "hp:c:b:i:m:o:" o; do
+    case "${o}" in
+        h)
+            echo -e "$HELP"
+            exit
+        ;;
+        p)
+            if [[ "$OPTARG" != "a4" && "$OPTARG" != "letter" ]]; then
+                error "Invalid paper type '$OPTARG'. Must be 'a4' or 'letter'."
+            fi
+            PAPER="$OPTARG"
+        ;;
+        c)
+            check_file_exists "$OPTARG"
+            COVER="$OPTARG"
+            COVERSIZE="$(identify -format "%w" "$COVER")"
+        ;;
+        b)
+            if [[ "$OPTARG" != "no" && "$OPTARG" != "image" ]]; then
+                error "Invalid back type '$OPTARG'. Must be 'no' or 'image'."
+            fi
+            BACKTYPE="$OPTARG"
+        ;;
+        i)
+            if [[ "$BACKTYPE" != "image" ]]; then
+                error "-i option requires back type to be 'image'."
+            fi
+            check_file_exists "$OPTARG"
+            BACKIMG="$OPTARG"
+        ;;
+        m)
+            BORDER="TRUE"
+            BORDER_WIDTH="$OPTARG"
+        ;;
+        o)
+            check_output_file "$OPTARG"
+            OUTPUT="$OPTARG"
+        ;;
+        *)
+            echo -e "$USAGE"
+            exit 1
+        ;;
+    esac
+done
+
+
+# check if something is missing
+[[ -z "$PAPER" ]] && error "Missing paper format (-p)."
+[[ -z "$COVER" ]] && error "Missing cover image (-c)."
+[[ -z "$BACKTYPE" ]] && error "Missing back type (-b)."
+[[ -z "$OUTPUT" ]] && error "Missing output file (-o)."
+[[ "$BACKTYPE" == "image" && -z "$BACKIMG" ]] && error "Missing back image (-i) for back type 'image'."
+
+
 # function to convert mm to px with dpi
 CONVERT() { awk -v mm="$1" -v dpi="$2" 'BEGIN{printf("%d", mm/25.4*dpi + 0.5)}'; }
 
@@ -158,6 +321,7 @@ CO_PX="$(CONVERT "$CO_MM" "$DPI")"
 # Width and Height of paper in mm
 A4MM_W="210"
 A4MM_H="297"
+
 LTMM_W="216"
 LTMM_H="279"
 
@@ -190,8 +354,6 @@ fi
 
 
 # add the cover art set to the right size, rotated left by 90d and shifted up by (cover art size) / 2
-# TODO: change rotation to a variable to allow different folding points via argument
-# TODO: make command multi-line for readibility
 magick -colorspace sRGB -type TrueColor -depth 8 "$OUTPUT" \( "$COVER" -resize ${CO_PX}x${CO_PX} -rotate 270 \) -gravity center -geometry +0-$((CO_PX/2)) -composite "$OUTPUT" > /dev/null