added Linux support to battery prompt segment

README.md

@@ -71,7 +71,7 @@ configuration is the default:
 The segments that are currently available are:
 
 * [aws](#aws) - The current AWS profile, if active.
-* [battery](#battery) - Current battery status(OS X only).
+* [battery](#battery) - Current battery status.
 * [context](#context) - Your username and host.
 * [dir](#dir) - Your current working directory.
 * **history** - The command number for the current line.
@@ -104,8 +104,8 @@ your `~/.zshrc`:
 
 ##### battery
 
-This segment will display your current battery status on an OS X system(fails gracefully
+This segment will display your current battery status (fails gracefully
-on systems without a battery and non OS X systems). It can be customized in your .zshrc
+on systems without a battery). It can be customized in your .zshrc
 with the environment variables detailed below with their default values.
 
     POWERLEVEL9K_BATTERY_CHARGING="yellow"
@@ -116,6 +116,7 @@ with the environment variables detailed below with their default values.
 
 In addition to the above it supports standard _FOREGROUND value without affecting the icon color
 
+Supports both OS X and Linux(time remaining is only output in OS X)
 
 
 ##### context

powerlevel9k.zsh-theme

@@ -615,10 +615,7 @@ prompt_aws() {
 }
 
 prompt_battery() {
-  if [[ -f /usr/sbin/ioreg && -x /usr/sbin/ioreg ]]; then
+  icons[BATTERY_ICON]=$'\UE894'
-    # return if there is no battery on system
-    [[ -z $(ioreg -n AppleSmartBattery | grep MaxCapacity) ]] && return
-
   # set default values of not specified in shell
   [[ -z $POWERLEVEL9K_BATTERY_CHARGING ]] && POWERLEVEL9K_BATTERY_CHARGING="yellow"
   [[ -z $POWERLEVEL9K_BATTERY_CHARGED ]] && POWERLEVEL9K_BATTERY_CHARGED="green"
@@ -627,6 +624,10 @@ prompt_battery() {
   [[ -z $POWERLEVEL9K_BATTERY_LOW_COLOR ]] && POWERLEVEL9K_BATTERY_LOW_COLOR="red"
   [[ -z $POWERLEVEL9K_BATTERY_FOREGROUND ]] && local fg_color="$DEFAULT_COLOR" || local fg_color=$POWERLEVEL9K_BATTERY_FOREGROUND
 
+  if [[ $OS =~ OSX && -f /usr/sbin/ioreg && -x /usr/sbin/ioreg ]]; then
+    # return if there is no battery on system
+    [[ -z $(ioreg -n AppleSmartBattery | grep MaxCapacity) ]] && return
+
     # get charge status
     [[ $(ioreg -n AppleSmartBattery | grep ExternalConnected | awk '{ print $5 }') =~ "Yes" ]] && local connected=true
     [[ $(ioreg -n AppleSmartBattery | grep IsCharging | awk '{ print $5 }') =~ "Yes" ]] && local charging=true
@@ -642,18 +643,37 @@ prompt_battery() {
     local max_capacity=$(ioreg -n AppleSmartBattery | grep MaxCapacity | awk '{ print $5 }')
     local current_capacity=$(ioreg -n AppleSmartBattery | grep CurrentCapacity | awk '{ print $5 }')
 
-    # logic for string output
     [[ ! -z $max_capacity && ! -z $current_capacity ]] && local bat_percent=$(ruby -e "puts ($current_capacity.to_f / $max_capacity.to_f * 100).round.to_i")
-    [[ $charging =~ true && $connected =~ true ]] && local conn="%F{$POWERLEVEL9K_BATTERY_CHARGING}" && local remain="($tstring)"
+
+    # logic for string output
+    [[ $charging =~ true && $connected =~ true ]] && local conn="%F{$POWERLEVEL9K_BATTERY_CHARGING}" && local remain=" ($tstring)"
     [[ ! $charging =~ true && $connected =~ true ]] && local conn="%F{$POWERLEVEL9K_BATTERY_CHARGED}" && local remain=""
     if [[ ! $connected =~ true ]]; then
-      [[ $bat_percent -lt $POWERLVEL9K_BATTERY_LOW_THRESHOLD ]] && local conn="%F{$POWERLEVEL9K_BATTERY_LOW_COLOR}" || local conn="%F{$POWERLEVEL9K_BATTERY_DISCONNECTED}"
+      [[ $bat_percent -lt $POWERLEVEL9K_BATTERY_LOW_THRESHOLD ]] && local conn="%F{$POWERLEVEL9K_BATTERY_LOW_COLOR}" || local conn="%F{$POWERLEVEL9K_BATTERY_DISCONNECTED}"
-      local remain="($tstring)"
+      local remain=" ($tstring)"
+    fi
+  fi
+
+  if [[ $OS =~ Linux ]]; then
+    local sysp="/sys/class/power_supply"
+    # reported BAT0 or BAT1 depending on kernel version
+    [[ -a $sysp/BAT0 ]] && local bat=$sysp/BAT0
+    [[ -a $sysp/BAT1 ]] && local bat=$sysp/BAT1
+
+    # return if no battery found
+    [[ -z $bat ]] && return
+
+    local bat_percent=$(cat $bat/capacity)
+    [[ $(cat $bat/status) =~ Charging ]] && local connected=true
+    [[ $(cat $bat/status) =~ Charging && $bat_percent =~ 100 ]] && local conn="%F{$POWERLEVEL9K_BATTERY_CHARGED}"
+    [[ $(cat $bat/status) =~ Charging && $bat_percent -lt 100 ]] && local conn="%F{$POWERLEVEL9K_BATTERY_CHARGING}"
+    if [[ ! $connected =~ true ]]; then
+      [[ $bat_percent -lt $POWERLEVEL9K_BATTERY_LOW_THRESHOLD ]] && local conn="%F{$POWERLEVEL9K_BATTERY_LOW_COLOR}" || local conn="%F{$POWERLEVEL9K_BATTERY_DISCONNECTED}"
+    fi
   fi
 
   # display prompt_segment
-    [[ ! -z $bat_percent ]] && "$1_prompt_segment" "$0" "black" "$DEFAULT_COLOR" "$conn$(print_icon 'BATTERY_ICON')%F{$fg_color} $bat_percent%% $remain"
+  [[ ! -z $bat_percent ]] && "$1_prompt_segment" "$0" "black" "$DEFAULT_COLOR" "$conn$(print_icon 'BATTERY_ICON')%F{$fg_color} $bat_percent%%$remain"
-  fi
 }
 
 # Context: user@hostname (who am I and where am I)