Added support for Mac to battery plugin

plugins/battery/battery.plugin.zsh

-if [[ $(acpi 2&>/dev/null | grep -c '^Battery.*Discharging') -gt 0 ]] ; then
-  function battery_pct_remaining() { echo "$(acpi | cut -f2 -d ',' | tr -cd '[:digit:]')" }
-  function battery_time_remaining() { echo $(acpi | cut -f3 -d ',') }
-  function battery_pct_prompt() {
-    b=$(battery_pct_remaining)
-    if [ $b -gt 50 ] ; then
-      color='green'
-    elif [ $b -gt 20 ] ; then
-      color='yellow'
+###########################################
+# Battery plugin for oh-my-zsh            #
+# Original Author: Peter hoeg (peterhoeg) #
+# Email: peter@speartail.com              #
+###########################################
+# Author: Sean Jones (neuralsandwich)     #
+# Email: neuralsandwich@gmail.com         #
+# Modified to add support for Apple Mac   #
+###########################################
+
+if [[ $(uname) -eq "Darwin" ]] ; then
+
+  function battery_pct_remaining() {
+    if [[ $(ioreg -rc AppleSmartBattery | grep -c '^.*"ExternalConnected"\ =\ No') -eq 1 ]] ; then
+      typeset -F maxcapacity=$(ioreg -rc "AppleSmartBattery"| grep '^.*"MaxCapacity"\ =\ ' | sed -e 's/^.*"MaxCapacity"\ =\ //')
+      typeset -F currentcapacity=$(ioreg -rc "AppleSmartBattery"| grep '^.*"CurrentCapacity"\ =\ ' | sed -e 's/^.*CurrentCapacity"\ =\ //')
+      integer i=$(((currentcapacity/maxcapacity) * 100))
+      echo $i
     else
-      color='red'
+      echo "External Power"
     fi
-    echo "%{$fg[$color]%}[$(battery_pct_remaining)%%]%{$reset_color%}"
   }
-else
-  error_msg='no battery'
-  function battery_pct_remaining() { echo $error_msg }
-  function battery_time_remaining() { echo $error_msg }
-  function battery_pct_prompt() { echo '' }
+
+  function battery_time_remaining() {
+    if [[ $(ioreg -rc AppleSmartBattery | grep -c '^.*"ExternalConnected"\ =\ No') -eq 1 ]] ; then
+      timeremaining=$(ioreg -rc "AppleSmartBattery"| grep '^.*"AvgTimeToEmpty"\ =\ ' | sed -e 's/^.*"AvgTimeToEmpty"\ =\ //')
+      echo "~$((timeremaining / 60)):$((timeremaining % 60))"
+    else
+      echo "∞"
+    fi
+  }
+
+  function battery_pct_prompt () {
+    if [[ $(ioreg -rc AppleSmartBattery | grep -c '^.*"ExternalConnected"\ =\ No') -eq 1 ]] ; then
+      b=$(battery_pct_remaining)
+      if [ $b -gt 50 ] ; then
+        color='green'
+      elif [ $b -gt 20 ] ; then
+        color='yellow'
+      else
+        color='red'
+      fi
+      echo "%{$fg[$color]%}[$(battery_pct_remaining)%%]%{$reset_color%}"
+    else
+      echo ""
+    fi
+  }
+
+elif [[ $(uname) -eq "Linux"  ]] ; then
+
+  if [[ $(acpi 2&>/dev/null | grep -c '^Battery.*Discharging') -gt 0 ]] ; then
+    function battery_pct_remaining() { echo "$(acpi | cut -f2 -d ',' | tr -cd '[:digit:]')" }
+    function battery_time_remaining() { echo $(acpi | cut -f3 -d ',') }
+    function battery_pct_prompt() {
+      b=$(battery_pct_remaining)
+      if [ $b -gt 50 ] ; then
+        color='green'
+      elif [ $b -gt 20 ] ; then
+        color='yellow'
+      else
+        color='red'
+      fi
+      echo "%{$fg[$color]%}[$(battery_pct_remaining)%%]%{$reset_color%}"
+    }
+  else
+    error_msg='no battery'
+    function battery_pct_remaining() { echo $error_msg }
+    function battery_time_remaining() { echo $error_msg }
+    function battery_pct_prompt() { echo '' }
+  fi
 fi