app: make DataStore a class and refine on each platform
[nit.git] / lib / ios / data_store.nit
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2 #
3 # Licensed under the Apache License, Version 2.0 (the "License");
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5 # You may obtain a copy of the License at
6 #
7 # http://www.apache.org/licenses/LICENSE-2.0
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9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
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12 # See the License for the specific language governing permissions and
13 # limitations under the License.
14
15 # Implements `app::data_store` using `NSUserDefaults`
16 module data_store
17
18 import app::data_store
19 import cocoa::foundation
20 private import json
21
22 redef class DataStore
23
24 # The `NSUserDefaults` used to implement `DataStore`
25 var user_defaults = new NSUserDefaults.standard_user_defaults is lazy
26
27 redef fun [](key)
28 do
29 var nsstr = user_defaults.string_for_key(key.to_nsstring)
30
31 if nsstr.address_is_null then return null
32
33 # TODO report errors
34 var deserializer = new JsonDeserializer(nsstr.to_s)
35 return deserializer.deserialize
36 end
37
38 redef fun []=(key, value)
39 do
40 var nsobject: NSString
41
42 if value == null then
43 nsobject = new NSString.nil
44 else
45 var serialized_string = new StringWriter
46 var serializer = new JsonSerializer(serialized_string)
47 serializer.serialize(value)
48
49 # TODO report errors
50 nsobject = serialized_string.to_s.to_nsstring
51 end
52
53 user_defaults.set_object(nsobject, key.to_nsstring)
54 end
55 end