Refactor of the i3-lock-wrapper

Made it a bit more tolerant of missing binaries. Broke bits into functions.
Added more comments.

1 files changed, 89 insertions, 16 deletions

diff --git a/i3-lock-wrapper b/i3-lock-wrapper
index 556ab5a..f8f2c70 100755
--- a/i3-lock-wrapper
+++ b/i3-lock-wrapper
@@ -3,30 +3,103 @@
 # Performs a standard screen lock, with an extra bit of style. Before locking
 # the screen, takes a screenshot of the current display and programatically
 # blurs and desaturates the image, using that for the lock screen background. A
-# mighty neat effect.
+# mighty neat effect. 
 #
 # Requirements: i3-lock imagemagick [scrot] [xbacklight]
 #
 
-base=/tmp/i3-lock-wrapper-$(date "+%s")
-file1=base.jpg
-file2=base2.png
 
-if [[ $(which import) ]]; then
-  import -window root "$file1"
-elif [[ $(which scrot) ]]; then
-  scrot -d0 "$file1"
-else
-  echo "Screenshot command not found (scrot or import). Exiting."
-fi
+#
+# Generates the command to execute for taking a screenshot and applying affects
+# for use as the lockscreen wallpaper. Note that this does not execute the
+# command. It only generates it.
+#
+# @param out_file Path to save the lockscreen wallpaper to
+#
+function gen_wallpaper_cmd {
+  # Return early if argument 1 not specified
+  [[ -z ${1} ]] && return
+
+  out_file=${1}
+  tmp_file="/tmp/i3lock$(date '+%s')screen.jpg"
+
+  screenshot_cmd=""
+  if [[ $(which import 2>/dev/null) ]]; then
+    screenshot_cmd="$(which import) -window root ${tmp_file}"
+  elif [[ $(which scrot 2>/dev/null) ]]; then
+    screenshot_cmd="$(which scrot) -d0 ${tmp_file}"
+  fi
+
+  # Generate the wallpaper gen command
+  if [[ ${screenshot_cmd} != "" ]]; then
+    # Generate the lockscreen background/screenshot (blurred and slightly less
+    # saturated)
+    out=${screenshot_cmd}
+    # Add the image blur command
+    out=${out}' && '
+    out=${out}"convert ${tmp_file} -blur 0x4 -modulate 110,50 ${out_file}"
+    # Add command to clean up the original screenshot file
+    out="${out} && "
+    out="${out} rm ${tmp_file}"
+    echo "${out}"
+  fi
+  # Else we echo nothing, indicating no screenshotter was found
+}
+
+
+#
+# Locks the screen using i3lock command. Sets 
+#
+# @param bg Path to image to be used for the lockscreen wallpaper
+#
+function lock_screen {
+  # Return early if argument 1 not specified
+  [[ -z ${1} ]] && return
+
+  bg=${1}
+  dim=0
+  [[ $(which xbacklight) ]] && dim=1
+
+  if [[ ${dim} == 1 ]]; then
+    # Get the previous brightness so we can return to it.
+    prev_bright=$(xbacklight | cut -d '.' -f 1)
+
+    # Dim the screen, backgrounded so it continues fading after lock
+    xbacklight -set 3% -time 2000 -steps 150&
+  fi
+
+  # Lock, but remain in foreground so the unlock processes aren't executed yet
+  i3lock -i "${bg}" -n
+
+  # Resume original brightness
+  [[ ${dim} == 1 ]] && xbacklight -set ${prev_bright}% -time 2000 -steps 150
+}
+
+
+#
+# La fonction primaire
+#
+function main {
+  blurry_wallpaper='/tmp/i3lockwall.png'
+  # Get the program path that will screenshot for the background image
+  lock_wallpaper_cmd=$(gen_wallpaper_cmd ${blurry_wallpaper})
 
-convert "$file1" -blur 0x4 -modulate 110,50 "$file2"
+  if [[ ${lock_wallpaper_cmd} == "" ]]; then
+    echo "Screenshot command not found (scrot or import). Exiting."
+    exit 1
+  fi
 
+  # Execute in a subshell, or the double amperstands (&&) will fail. Seems I've
+  # discovered a querk of bash.
+  bash -c "${lock_wallpaper_cmd}"
 
-xbacklight -set 2% -time 3000 -steps 100&
+  # Execute the lock screen with the new fancy wallpaper
+  lock_screen ${blurry_wallpaper}
 
-i3lock -i "$file2" -n
+  # Cleanup the original screenshot and blurred counterpart
+  rm "${bg}"
+}
 
-xbacklight -set 10% -time 2000 -steps 100
 
-rm "$file1" "$file2"
+# Enter the script here
+main ${ARGV}