include("Automaton.jl")

using Test

@testset "simple simulation tests" begin

    @testset "test simple integrator (exposeState = false)" begin
        integrator = (x, u) -> (x+u, x+u)
        timespan = 1:10
        integrator! = Automaton.toInOut(integrator, 0)
        step_response = Automaton.evolution(integrator!, (1 for _ in timespan));
        output = [y for y in step_response];
        @test output == [i for i in timespan]
    end

    @testset "test simple integrator (exposeState = true)" begin
        integrator = (x, u) -> (x+u, x+u)
        timespan = 1:10
        integrator! = Automaton.toInOut(integrator, 0; exposeState=true)
        step_response = Automaton.evolution(integrator!, (1 for _ in timespan));
        output = [y for (y, x) in step_response];
        @test output == [i for i in timespan]
    end

    @testset "test if the exposed state is safe to manipulate" begin
        delay = (x, u) -> (u, x)
        # Intentionaly use mutable data structure (array) because
        # this will allow us to test if it is safe to manipulate the returned
        # state externaly!
        delay! = Automaton.toInOut(delay, [0]; exposeState=true)
        # Advance the automaton
        y, x = delay!([1])
        @test y == [0]
        @test x == [1]
        # Try to manipulate state.
        # This action should not affect the state of the automaton itself.
        x[1] = 5
        # Advance the automaton, again
        y, x = delay!([2])
        @test y == [1]
        @test x == [2]
    end

end