module Iddict exposing (..)

import Expect
import Fuzz exposing (Fuzzer)
import Internal.Tools.Iddict as Iddict exposing (Iddict)
import Json.Decode as D
import Json.Encode as E
import Test exposing (..)


fuzzer : Fuzzer a -> Fuzzer (Iddict a)
fuzzer fuz =
    fuz
        |> Fuzz.pair Fuzz.bool
        |> Fuzz.list
        |> Fuzz.map
            (\items ->
                List.foldl
                    (\( rm, item ) dict ->
                        case Iddict.insert item dict of
                            ( key, d ) ->
                                if rm then
                                    Iddict.remove key d

                                else
                                    d
                    )
                    Iddict.empty
                    items
            )


empty : Test
empty =
    describe "empty"
        [ test "isEmpty"
            (Iddict.empty
                |> Iddict.isEmpty
                |> Expect.equal True
                |> always
            )
        , fuzz Fuzz.int
            "No members"
            (\i ->
                Iddict.empty
                    |> Iddict.member i
                    |> Expect.equal False
            )
        , fuzz Fuzz.int
            "Get gets Nothing"
            (\i ->
                Iddict.empty
                    |> Iddict.get i
                    |> Expect.equal Nothing
            )
        , test "Size = 0"
            (Iddict.empty
                |> Iddict.size
                |> Expect.equal 0
                |> always
            )
        , test "No keys"
            (Iddict.empty
                |> Iddict.keys
                |> Expect.equal []
                |> always
            )
        , test "No values"
            (Iddict.empty
                |> Iddict.values
                |> Expect.equal []
                |> always
            )
        , test "JSON encode -> decode -> empty"
            (Iddict.empty
                |> Iddict.encode identity
                |> D.decodeValue (Iddict.decoder D.value)
                |> Expect.equal (Ok Iddict.empty)
                |> always
            )
        , test "JSON encode"
            (Iddict.empty
                |> Iddict.encode identity
                |> E.encode 0
                |> Expect.equal "{\"cursor\":0,\"dict\":{}}"
                |> always
            )
        , test "JSON decode"
            ("{\"cursor\":0,\"dict\":{}}"
                |> D.decodeString (Iddict.decoder D.value)
                |> Expect.equal (Ok Iddict.empty)
                |> always
            )
        ]


singleton : Test
singleton =
    let
        singleFuzzer : Fuzzer (Iddict Int)
        singleFuzzer =
            Fuzz.map
                (\i ->
                    Iddict.singleton i
                        |> Tuple.second
                )
                Fuzz.int
    in
    describe "singleton"
        [ fuzz singleFuzzer
            "not isEmpty"
            (\single ->
                single
                    |> Iddict.isEmpty
                    |> Expect.equal False
            )
        , fuzz Fuzz.int
            "singleton == insert empty"
            (\i ->
                Iddict.empty
                    |> Iddict.insert i
                    |> Expect.equal (Iddict.singleton i)
            )
        , fuzz Fuzz.int
            "First item is key 0"
            (\i ->
                Iddict.singleton i
                    |> Tuple.first
                    |> Expect.equal 0
            )
        , fuzz singleFuzzer
            "Key 0 is member"
            (\single ->
                single
                    |> Iddict.member 0
                    |> Expect.equal True
            )
        , fuzz Fuzz.int
            "Key 0 get returns Just value"
            (\i ->
                Iddict.singleton i
                    |> Tuple.second
                    |> Iddict.get 0
                    |> Expect.equal (Just i)
            )
        , fuzz singleFuzzer
            "Size == 1"
            (\single ->
                single
                    |> Iddict.size
                    |> Expect.equal 1
            )
        , fuzz Fuzz.int
            "Only key 0"
            (\i ->
                Iddict.singleton i
                    |> Tuple.second
                    |> Iddict.keys
                    |> Expect.equal [ 0 ]
            )
        , fuzz Fuzz.int
            "Only value value"
            (\i ->
                Iddict.singleton i
                    |> Tuple.second
                    |> Iddict.values
                    |> Expect.equal [ i ]
            )
        , fuzz singleFuzzer
            "JSON encode -> decode -> singleton"
            (\single ->
                single
                    |> Iddict.encode E.int
                    |> D.decodeValue (Iddict.decoder D.int)
                    |> Expect.equal (Ok single)
            )
        , fuzz Fuzz.int
            "JSON encode"
            (\i ->
                Iddict.singleton i
                    |> Tuple.second
                    |> Iddict.encode E.int
                    |> E.encode 0
                    |> Expect.equal ("{\"cursor\":1,\"dict\":{\"0\":" ++ String.fromInt i ++ "}}")
            )
        , fuzz Fuzz.int
            "JSON decode"
            (\i ->
                ("{\"cursor\":1,\"dict\":{\"0\":" ++ String.fromInt i ++ "}}")
                    |> D.decodeString (Iddict.decoder D.int)
                    |> Tuple.pair 0
                    |> Expect.equal (Iddict.singleton i |> Tuple.mapSecond Ok)
            )
        ]


insert : Test
insert =
    describe "insert"
        [ fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "Add something"
            (\d i ->
                case Iddict.insert i d of
                    ( key, dict ) ->
                        dict
                            |> Iddict.get key
                            |> Expect.equal (Just i)
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "Never isEmpty"
            (\d i ->
                Iddict.insert i d
                    |> Tuple.second
                    |> Iddict.isEmpty
                    |> Expect.equal False
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "New key"
            (\d i ->
                case Iddict.insert i d of
                    ( key, dict ) ->
                        dict
                            |> Iddict.remove key
                            |> Iddict.insert i
                            |> (\( newKey, _ ) ->
                                    Expect.notEqual key newKey
                               )
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "New dict"
            (\d i ->
                case Iddict.insert i d of
                    ( key, dict ) ->
                        dict
                            |> Iddict.remove key
                            |> Iddict.insert i
                            |> (\( _, newDict ) ->
                                    Expect.notEqual dict newDict
                               )
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "Inserted value is member"
            (\d i ->
                case Iddict.insert i d of
                    ( key, dict ) ->
                        dict
                            |> Iddict.member key
                            |> Expect.equal True
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "Get inserted value"
            (\d i ->
                case Iddict.insert i d of
                    ( key, dict ) ->
                        dict
                            |> Iddict.get key
                            |> Expect.equal (Just i)
            )
        , fuzz2 (fuzzer Fuzz.int)
            Fuzz.int
            "size = size + 1"
            (\d i ->
                case Iddict.insert i d of
                    ( _, dict ) ->
                        Expect.equal
                            (Iddict.size dict)
                            (Iddict.size d + 1)
            )
        ]