gui

#!/bin/bash

DIRECTORY="$(dirname "$0")"

closewindows() {
  kill $pid1 2>/dev/null || echo 'pid1 not found'
  kill $(cat "$DIRECTORY/pid2" 2>/dev/null) 2>/dev/null || echo 'pid2 not found'
}

error() {
  echo -e "\e[91m$1\e[39m" 1>&2
  
  closewindows
  #run cleanup function
  cleanup
  
  kill -w -s TERM $TOP_PID
}

export GDK_BACKEND=x11 #fix window placement on wayland
trap closewindows EXIT
export TOP_PID=$$

#list of subdirectory names. hidden directories not shown.
list="$(ls "$DIRECTORY"/*/ -d | sed "s|$DIRECTORY/||g" | sed -e 's-/$--')"

#clear currentclick
"$DIRECTORY"/clickhandler

checkimages() { #resize all *.png images to 500px wide
  #list of images found in screensaver folders - full paths
  imagelist="$(ls "$DIRECTORY"/*/*.png)"
  
  PREIFS="$IFS"
  IFS=$'\n'
  for image in $imagelist ;do
    #if backup image doesn't exist and image is not 500 pixel wide
    
    sc_original_path="$(dirname "$image")/screenshot-original.png"
    
    if [ ! -f "$sc_original_path" ];then
      #backup the image
      mv -f "$image" "$sc_original_path"
      
      if ! command -v identify >/dev/null || ! command -v convert >/dev/null ;then
        error "The identify and convert commands are necessary to resize screenshots.\nIf you are on a debian-based system, this should work: 'sudo apt install imagemagick'"
      fi
      
      if [ "$(identify -format '%w' "$sc_original_path")" != 500 ];then
        #resize the image to 500 pixels wide, and save it to screenshot.png
        convert "$sc_original_path" -resize 500x "$(dirname "$image")/screenshot.png"
      fi
      
    else
      #image is already 500px wide and/or backup image exists
      true
    fi
  done
  IFS="$PREIFS"
}
checkimages

cleanup() {
  rm -f "$DIRECTORY/window2-exitcode" "$DIRECTORY/pid2" "$DIRECTORY/pid1" "$DIRECTORY/window1-exitcode" "$DIRECTORY/currentclick"
}
#run cleanup function
cleanup

#check for dependencies
if ! command -v yad >/dev/null ;then
  error "The YAD dialog program must be installed.\nIf you are on a debian-based system, this should work: 'sudo apt install yad'"
elif ! command -v wine >/dev/null ;then
  error "Wine must be installed.\nUse Pi-Apps to install Wine.\n/~https://github.com/Botspot/pi-apps"
elif ! command -v xdpyinfo >/dev/null ;then
  error "In order to determine the dimensions of your screen, xdpyinfo must be installed.\nIf you are on a debian-based system, this should work: 'sudo apt install x11-utils'"
elif ! command -v xprintidle >/dev/null ;then
  error "In order to measure inactivity time, xprintidle is necessary.\nIf you are on a debian-based system, this should work: 'sudo apt install xprintidle'"
fi

#check for updates
if [ ! -f "${DIRECTORY}/no-update-check" ];then
  cd "$DIRECTORY"
  localhash="$(git rev-parse HEAD)"
  cd
  latesthash="$(git ls-remote /~https://github.com/Botspot/Screensavers HEAD | awk '{print $1}')"
  if [ "$localhash" != "$latesthash" ] && [ ! -z "$latesthash" ] && [ ! -z "$localhash" ];then
    echo -e "Updating..."
    git pull
    echo -e "To disable this, create a file named: '${DIRECTORY}/no-update-check'\n"
  fi
fi

#create menu launcher
if [ ! -f ~/.local/share/applications/windows-screensavers.desktop ];then
  echo "[Desktop Entry]
Exec=$DIRECTORY/gui
Icon=xscreensaver
Terminal=false
Name=Windows Screensavers
Comment=Select and configure Windows screensavers that run on your Pi with Wine
Type=Application
Categories=Settings;DesktopSettings;Security;X-XFCE;" > ~/.local/share/applications/windows-screensavers.desktop
  
fi

#Screen dimension stuff
{
screen_width="$(xdpyinfo | grep 'dimensions:' | tr 'x' '\n' | tr ' ' '\n' | sed -n 7p)"
screen_height="$(xdpyinfo | grep 'dimensions:' | tr 'x' '\n' | tr ' ' '\n' | sed -n 8p)"
#total dimensions for both windows side by side
height=450
width=700

yoffset=$(((screen_height/2)-(height/2)))

#width of first window
width1=200
#width of second window
width2=$((width - width1))

#screen offsets for window 1
xoffset1=$(((screen_width/2)-(width/2)))
#screen offsets for window 2
xoffset2=$(((screen_width/2)-(width/2)+width1))
}

#Deleting this file will kill the script
echo '' > "$DIRECTORY/closefile"
(while [ -f "$DIRECTORY/closefile" ];do
  sleep 1
done
error "exited" ) &


#screensaver list on the left, run in the background
(echo "$list" | yad --list --geometry=${width1}x${height}+${xoffset1}+${yoffset} \
  --class screensaver --window-icon=xscreensaver --title=' ' \
  --no-headers --column=item --select-action="$DIRECTORY"/clickhandler --no-buttons &
pid1=$!
echo $pid1 > "$DIRECTORY/pid1"
wait $pid1
echo $? > "$DIRECTORY/window1-exitcode"
rm -f "$DIRECTORY/closefile") &

#wait for pid1 file to exist (wait for window1 to launch)
while [ ! -f "$DIRECTORY/pid1" ];do
  sleep 0.1
done
pid1="$(cat "$DIRECTORY/pid1")"

#wait until a screensaver is clicked before launching second window
echo -n '' > "${DIRECTORY}/currentclick"
currentclick="$(read line < <(tail -f --retry "${DIRECTORY}/currentclick" 2>/dev/null) ; echo "$line")"

delay="$(cat "${DIRECTORY}/delay")"

while true;do #main loop that runs right pane forever
  currentclick="$(cat "${DIRECTORY}/currentclick")"
  #refreshes window2 each time a new list item is selected
  output="$(
  while true;do
    checkimages &
    #screensaver preview window
    [ ! -z "$pid2" ] && kill $pid2 # kill previous instance if it exists
    rm -f "$DIRECTORY/window2-exitcode"
    #display simplified window if only run.sh exists
    if [ -f "$DIRECTORY/$currentclick/install.sh" ];then
      (
      #display warning on wayland
      if [ ! -z "$WAYLAND_DISPLAY" ];then
        text=(--field='Warning: On Wayland the screensaver cannot start when computer is inactive! Clicking OK or Apply will not work. Just click Preview.:LBL' '')
      else
        text=()
      fi
      yad --geometry=${width2}x${height}+${xoffset2}+${yoffset} --title="$currentclick" --window-icon=xscreensaver --class screensaver \
        --form --columns=2 --separator='\n' \
        --field="Wait: ":NUM "$delay"'!1..60' --field="Settings...!!Installs the screensaver, then runs its settings.sh script.":FBTN "$DIRECTORY/settings" \
        "${text[@]}" \
        --field="minutes":RO "" --field="Preview!!Installs the screensaver, then runs it."$'\n'"The screensaver service won't be modified.":FBTN "$DIRECTORY/preview" \
        "$([ -f "$DIRECTORY/$currentclick/screenshot.png" ] && echo --image="$DIRECTORY/$currentclick/screenshot.png")" --image-on-top \
        --button="OK!!Installs the screensaver, then generates the screensaver service."$'\n'"The list of screensavers will close when finished.:0" --button="Cancel!!Don't make any changes.:2" --button="Apply!!Installs the screensaver, then generates the screensaver service."$'\n'"This window will reappear when finished.:4" &
      pid2=$!
      echo "$pid2" > "$DIRECTORY/pid2"
      
      #write exit code to file as long as it was not the termination exit code. (143)
      wait $pid2 ; exitcode2=$?
      if [ $exitcode2 != 143 ];then
        echo $exitcode2 > "$DIRECTORY/window2-exitcode"
      fi
      ) &
      
    else #install.sh does not exist, assume run.sh exists
      (
      yad --geometry=${width2}x${height}+${xoffset2}+${yoffset} --title="$currentclick" --window-icon=xscreensaver \
        "$([ -f "$DIRECTORY/$currentclick/screenshot.png" ] && echo --image="$DIRECTORY/$currentclick/screenshot.png")" --image-on-top \
        --button="Cancel!!Don't make any changes.:2" --button="Run script!!"${DIRECTORY}/$currentclick/run.sh":6" &
      pid2=$!
      echo "$pid2" > "$DIRECTORY/pid2"
      
      #write exit code to file as long as it was not the termination exit code. (143)
      wait $pid2 ; exitcode2=$?
      if [ $exitcode2 != 143 ];then
        echo $exitcode2 > "$DIRECTORY/window2-exitcode"
      fi
      ) &
      
    fi
    sleep 0.5
    pid2="$(cat "$DIRECTORY/pid2")"
    
    #wait until selection in window1 changes
    currentclick="$(while read line ;do [ "$line" != "$currentclick" ] && break ; done < <(tail -f --retry "${DIRECTORY}/currentclick" 2>/dev/null) ; echo "$line")"
    
    if [ -f "$DIRECTORY/window2-exitcode" ];then
      #if exitcode file exists, exit this while loop with that exit code.
      echo "exit $(cat "$DIRECTORY/window2-exitcode")" 1>&2
      exit "$(cat "$DIRECTORY/window2-exitcode")"
      break
    elif [ ! -f "${DIRECTORY}/currentclick" ];then
      #exit if currentclick missing
      exit 0
    fi
  done
  )"
  
  button=$?
  
  echo "Output: ${output}EOO"
  
  delay="$(echo "$output" | sed -n 1p)"
  if [ -z "$delay" ];then
    #read delay value from file if it's blank
    delay="$(cat "${DIRECTORY}/delay")"
  fi
  
  echo "Delay: $delay"
  
  currentclick="$(cat "${DIRECTORY}/currentclick")"
  
  case $button in
    1|252)
      echo "User exited."
      exit 0
      
      ;;
    0|4)
      echo "Button: OK or Apply"
      
      if [ "$currentclick" == none ];then
        echo "Removing systemd service..."
        #Stop existing screensaver.service
        if [ -f /etc/systemd/system/screensaver.service ]; then
          echo "Stopping the service first..."
          sudo systemctl stop screensaver
          sudo systemctl disable screensaver
          sudo rm /etc/systemd/system/screensaver.service
        fi
        
        echo "Reloading systemd daemon..."
        sudo systemctl daemon-reload
        
      else #screensaver is not 'none'
        echo "Running install.sh for '$currentclick'..."
        #run selected screensaver's install script
        "${DIRECTORY}/$currentclick/install.sh"
        
        
        echo "Creating daemon script for '$currentclick'..."
        #write new delay value to file
        echo "$delay" > "${DIRECTORY}/delay"
        
        #create screensaver daemon script that waits specified amount of time
        echo "#!/bin/bash
export DISPLAY=:0

while true;do
  
  #if idle time is greater than set time, and no audio devices are playing (stackoverflow.com/a/17404952)
  
  if [ "\$"(xprintidle) -gt $(($(cat "${DIRECTORY}/delay")*1000*60)) ] && [ -z "'"$(grep -r RUNNING /proc/asound/card*/pcm*/sub*/status)"'" ];then
    "\""${DIRECTORY}/$currentclick/run.sh"\""
  fi
  
  sleep 60
done" > ~/.screensavers/daemon.sh
        chmod +x ~/.screensavers/daemon.sh
        
        #Stop existing screensaver.service
        if [ -f /etc/systemd/system/screensaver.service ]; then
          echo "Stopping the systemd service first..."
          sudo systemctl stop screensaver
          echo "Disabling service..."
          sudo systemctl disable screensaver
        fi
        
        echo "Creating systemd service for '$currentclick'..."
        #create the service
        echo "[Unit]
        Description=Screensaver
        
        [Service]
        User=pi
        Type=simple
        ExecStart=/bin/bash $HOME/.screensavers/daemon.sh
        
        [Install]
        WantedBy=multi-user.target" | sudo tee /etc/systemd/system/screensaver.service >/dev/null
        
        echo "Reloading systemd daemon..."
        sudo systemctl daemon-reload
        echo "Starting the service..."
        sudo systemctl start screensaver
        echo "Enabling the service..."
        sudo systemctl enable screensaver
        
        #print instructions
        echo -e "\e[93m
Verify service is running  : sudo systemctl status screensaver
Enable on startup          : sudo systemctl enable screensaver
Disable on startup         : sudo systemctl disable screensaver
Start screensaver service  : sudo systemctl start screensaver
Stop screensaver service   : sudo systemctl stop screensaver\e[39m"
      
      fi
      #if OK clicked, exit program now
      if [ $button == 0 ];then
        echo "OK button clicked, so exiting now"
        exit 0
      fi
      
      ;;
    2)
      echo "Button: Cancel"
      exit 0
      ;;
    6)
      echo "Button: Run script"
      echo "Running run.sh for '$currentclick'..."
      #run selected screensaver's install script
      "${DIRECTORY}/$currentclick/run.sh"
      exit 0
      ;;
    *)
      error "Unknown button: $button"
      ;;
  esac
  
done