using Test

include("perfect-numbers.jl")

@testset "Perfect numbers" begin

    @testset "Smallest perfect number is classified correctly" begin
        @test isperfect(6)
    end

    @testset "Medium perfect number is classified correctly" begin
        @test isperfect(28)
    end

    @testset "Large perfect number is classified correctly" begin
        @test isperfect(33550336)
    end
end

@testset "Abundant numbers" begin

    @testset "Smallest abundant number is classified correctly" begin
        @test isabundant(12)
    end

    @testset "Medium abundant number is classified correctly" begin
        @test isabundant(30)
    end

    @testset "Large abundant number is classified correctly" begin
        @test isabundant(33550335)
    end
end

@testset "Deficient numbers" begin

    @testset "Smallest prime deficient number is classified correctly" begin
        @test isdeficient(2)
    end

    @testset "Smallest non-prime deficient number is classified correctly" begin
        @test isdeficient(4)
    end

    @testset "Medium deficient number is classified correctly" begin
        @test isdeficient(32)
    end

    @testset "Large deficient number is classified correctly" begin
        @test isdeficient(33550337)
    end

    @testset "Edge case (no factors other than itself) is classified correctly" begin
        @test isdeficient(1)
    end
end

@testset "Invalid inputs" begin

    @testset "Zero is rejected (not a natural number)" begin
        @test_throws DomainError isdeficient(0)
        @test_throws DomainError isperfect(0)
        @test_throws DomainError isabundant(0)
    end

    @testset "Negative integer is rejected (not a natural number)" begin
        @test_throws DomainError isdeficient(-1)
        @test_throws DomainError isperfect(-1)
        @test_throws DomainError isabundant(-1)
    end
end