defmodule Cargo do
    @behaviour Problem
    alias Types.Chromosome

    @impl true
    def genotype do
        genes = for _ <- 1..10, do: Enum.random(0..1)
        %Chromosome{genes: genes, size: 10}
    end

    @impl true
    def fitness_function(chromosome) do
        profits = [6, 5, 8, 9, 6, 7, 3, 1, 2, 6]
        weights = [10, 6, 8, 7, 10, 9, 7, 11, 6, 8]
        weight_limit = 40

        potential_profits =
            chromosome.genes
            |> Enum.zip(profits)
            |> Enum.map(fn {g, p} -> g * p end)
            |> Enum.sum()

        over_limit? =
            chromosome.genes
            |> Enum.zip(weights)
            |> Enum.map(fn {c, w} -> c * w end)
            |> Enum.sum()
            |> Kernel.>(weight_limit)

        profits = if over_limit?, do: 0, else: potential_profits
        profits
    end

    @impl true
    def terminate?(population, _generation) do
        Enum.max_by(population, &Cargo.fitness_function/1).fitness == 53
    end
end

soln = Genetic.run(Cargo, population_size: 50)

IO.write("\n")
IO.inspect(soln)

weight = soln.genes
    |> Enum.zip([10, 6, 8, 7, 10, 9, 7, 11, 6, 8])
    |> Enum.map(fn {g, w} -> w*g end)
    |> Enum.sum()

IO.write("\nWeight is: #{weight}\n")