using Random

function test_known_graph(name::String, n, fusion_test=true)
@testset "Test $name Graph ($n)" begin
    graph = parse_abc(joinpath(@__DIR__, "..", "input", "$name.txt"))
    props = graph_properties(graph)

    if (fusion_test) 
        test_node_fusion(graph)
    end
    test_random_walk(graph, n)
end
end

function test_node_fusion(g::DAG)
@testset "Test Node Fusion" begin
    props = graph_properties(g)

    options = get_operations(g)

    nodes_number = length(g.nodes)
    data = props.data
    compute_effort = props.compute_effort

    while !isempty(options.nodeFusions)
        fusion = first(options.nodeFusions)

        @test typeof(fusion) <: NodeFusion

        push_operation!(g, fusion)

        props = graph_properties(g)
        @test props.data < data
        @test props.compute_effort == compute_effort

        nodes_number = length(g.nodes)
        data = props.data
        compute_effort = props.compute_effort

        options = get_operations(g)
    end
end
end

function test_random_walk(g::DAG, n::Int64)
@testset "Test Random Walk ($n)" begin
    # the purpose here is to do "random" operations and reverse them again and validate that the graph stays the same and doesn't diverge
    reset_graph!(g)

    properties = graph_properties(g)

    for i = 1:n
        # choose push or pop
        if rand(Bool)
            # push
            opt = get_operations(g)

            # choose one of fuse/split/reduce
            option = rand(1:3)
            if option == 1 && !isempty(opt.nodeFusions)
                push_operation!(g, rand(collect(opt.nodeFusions)))
            elseif option == 2 && !isempty(opt.nodeReductions)
                push_operation!(g, rand(collect(opt.nodeReductions)))
            elseif option == 3 && !isempty(opt.nodeSplits)
                push_operation!(g, rand(collect(opt.nodeSplits)))
            else
                i = i - 1
            end
        else
            # pop
            if (can_pop(g))
                pop_operation!(g)
            else
                i = i - 1
            end
        end
    end

    reset_graph!(g)

    @test properties == graph_properties(g)
end
end

Random.seed!(0)

@testset "Test Known ABC-Graphs" begin
    test_known_graph("AB->AB", 10000)
    test_known_graph("AB->ABBB", 10000)
    test_known_graph("AB->ABBBBB", 1000, false)
end
println("Known Graph Testing Complete!")