module UtilTest where

import Test.Tasty.Hspec
import Control.Exception (evaluate)
import Control.DeepSeq

import qualified Data.Aeson as Aeson
import Data.Aeson ((.=), object, toJSON)

import Util


spec_camelToKebabCase :: Spec
spec_camelToKebabCase = do
    "foobar" ~> "foobar"
    "s3" ~> "s3"
    "fooBarBar" ~> "foo-bar-bar"
    "s3Folder" ~> "s3-folder"
    "S3Folder" ~> "s3-folder"
  where
    camel ~> kebab = it (camel ++ " -> " ++ kebab) $ do
        camelToKebabCase camel `shouldBe` kebab

spec_onFirst :: Spec
spec_onFirst = do
    it "Returns empty list for empty list" $ do
        (onFirst id ([] :: [Char])) `shouldBe` []
    it "Applies given method on first element of list" $ do
        onFirst (+ 1) ([1, 2, 3] :: [Int]) `shouldBe` [2, 2, 3]

spec_toLowerFirst :: Spec
spec_toLowerFirst = do
    it "Lowers first letter of string" $ do
        toLowerFirst "FooBar" `shouldBe` "fooBar"

spec_toUpperFirst :: Spec
spec_toUpperFirst = do
    it "Capitalizes first letter of string" $ do
        toUpperFirst "fooBar" `shouldBe` "FooBar"

spec_jsonSet :: Spec
spec_jsonSet = do
    let inputObj = object
            [ "prop1" .= ("first" :: String)
            ]

    it "When input JSON is not an object, throws an error." $ do
        (evaluate . force) (jsonSet "someProp" (Aeson.Number 23) (Aeson.Bool True))
            `shouldThrow` errorCall "Input JSON must be an object"
    
    it "When a new property is set, result object contains it along with the original ones." $ do
        let expectedObj = object
                [ "prop1" .= ("first" :: String)
                , "newProp" .= (23 :: Int)
                ]
        (jsonSet "newProp" (Aeson.Number 23) inputObj) `shouldBe` expectedObj

    it "When an existing property is set, it is overwritten in the result object." $ do
        let newStrValue = "newVal" :: String
        let expectedObj = object
                [ "prop1" .= newStrValue
                ]
        (jsonSet "prop1" (toJSON newStrValue) inputObj) `shouldBe` expectedObj