module Snake.Tests.M05Game

open Expecto
open Snake
open Snake.Tests.Fixtures

let private replayCase () = List.head (cases "m05-replay")
let private start () = gameState (arg 0 (replayCase ()))
let private actions () = list action (arg 1 (replayCase ()))

[<Tests>]
let tests =
    testList "M05 Game" [
        yield! fixtureTests "m05-update" "update" (fun c ->
            Expect.equal (Game.update (gameState (arg 0 c)) (action (arg 1 c))) (gameState (expected c)) "update")

        yield! fixtureTests "m05-replay" "replay" (fun c ->
            Expect.equal (Game.replay (gameState (arg 0 c)) (list action (arg 1 c))) (gameState (expected c)) "replay")

        yield! fixtureTests "m05-history" "history" (fun c ->
            Expect.equal
                (Game.history (gameState (arg 0 c)) (list action (arg 1 c)))
                (list gameState (expected c))
                "history")

        testCase "history has one more state than there are actions" (fun () ->
            Expect.equal (List.length (Game.history (start ()) (actions ()))) (List.length (actions ()) + 1) "length")

        testCase "history starts at the start state and ends where replay ends" (fun () ->
            let states = Game.history (start ()) (actions ())
            Expect.equal (List.head states) (start ()) "first"
            Expect.equal (List.last states) (Game.replay (start ()) (actions ())) "last")
    ]