Add -s "save" option

Sets the output file to the path of the input file

src/cli.coffee

@@ -15,6 +15,7 @@ program
   .usage('<theme> [options]')
   .option('-c, --config <file>', 'The config file the theme should be applied to. Defaults to the default i3 location.')
   .option('-o, --output <file>', 'Applies the theme, attempts to validate the result, and writes it to <file>. Prints to STDOUT if no output file is given.')
+  .option('-s, --save', 'Sets the output file to the path of the input file')
   .option('-r, --reload', 'Apply the theme by reloading your config with i3-msg (restart may be required to apply bar colors)')
   .option('-l, --list-all', 'Prints a list of all available themes.')
   .parse(process.argv)
@@ -84,7 +85,15 @@ configPath = switch
 config = mkConfig theme, sh.cat(configPath)
 
 # no output file specified. echo result to stdout and we are done.
-unless program.output
+outputPath = switch
+  when program.output
+    program.output
+  when program.save
+    configPath
+  else
+    null
+
+unless outputPath
   sh.echo config
   sh.exec('i3-msg reload') if program.reload
   process.exit 0
@@ -112,6 +121,7 @@ if tmpdir and not process.env.I3STYLETEST
   sh.cp(configPath, tmpPath)
 
 # finally write the file to the specified location
-fs.writeFile program.output, config, (err) ->
+fs.writeFile outputPath, config, (err) ->
   exitWithError "Could not write to file: #{program.output}\n\n#{err}" if err
+  sh.echo "Applied #{program.args[0]} theme to #{outputPath}"
   sh.exec('i3-msg reload') if program.reload