Added Process entire file, and configuration settings

Default (OSX).sublime-keymap

@@ -1,3 +1,14 @@
 [
-	{ "keys": ["super+ctrl+j"], "command": "prettyjson" }
+	// Only use this for the "source.json" scope
+    {
+        "keys": ["super+ctrl+j"],
+        "command": "prettyjson",
+        "context": [
+        {
+	        "key": "selector",
+	        "operator": "equal",
+	        "operand": "source.json"
+	    }
+	    ]
+	}
 ]

Pretty JSON.sublime-settings

@@ -0,0 +1,5 @@
+{
+	"use_entire_file_if_no_selection" : true,
+	"indent_size" : 4,
+	"sort_keys" : true
+}

PrettyJson.py

@@ -2,14 +2,23 @@ import sublime
 import sublime_plugin
 import json
 
+s = sublime.load_settings("Pretty JSON.sublime-settings")
 
 class PrettyjsonCommand(sublime_plugin.TextCommand):
     def run(self, edit):
         for region in self.view.sel():
-            selection = self.view.substr(region)
-
+            # If no selection, use the entire file as the selection
+            # TODO: Use a setting to determine whether to do the entire file
+            # if region.empty():
+            if region.empty() and s.get("use_entire_file_if_no_selection"):
+                selection = sublime.Region(0, self.view.size())
+            else:
+                selection = region
+            
             try:
-                obj = json.loads(selection)
-                self.view.replace(edit, region, json.dumps(obj, indent=4, ensure_ascii=False, sort_keys=True))
+                obj = json.loads(self.view.substr(selection))
+                # TODO: Use a setting for the sort_keys value
+                # TODO: Use a setting for the indent value
+                self.view.replace(edit, selection, json.dumps(obj, indent=s.get("indent_size", 4), ensure_ascii=False, sort_keys=s.get("sort_keys", True)))
             except Exception, e:
                 sublime.status_message(str(e))