using Plots, Test
import RecipesPipeline

@testset "Contours" begin
    @testset "check_contour_levels" begin
        @test Plots.check_contour_levels(2) === nothing
        @test Plots.check_contour_levels(-1.0:0.2:10.0) === nothing
        @test Plots.check_contour_levels([-100, -2, -1, 0, 1, 2, 100]) === nothing
        @test_throws ArgumentError Plots.check_contour_levels(1.0)
        @test_throws ArgumentError Plots.check_contour_levels((1, 2, 3))
        @test_throws ArgumentError Plots.check_contour_levels(-3)
    end

    @testset "RecipesPipeline.preprocess_attributes!" begin
        function equal_after_pipeline(kw)
            kw′ = deepcopy(kw)
            RecipesPipeline.preprocess_attributes!(kw′)
            kw == kw′
        end

        @test equal_after_pipeline(KW(:levels => 1))
        @test equal_after_pipeline(KW(:levels => 1:10))
        @test equal_after_pipeline(KW(:levels => [1.0, 3.0, 5.0]))
        @test_throws ArgumentError RecipesPipeline.preprocess_attributes!(
            KW(:levels => 1.0),
        )
        @test_throws ArgumentError RecipesPipeline.preprocess_attributes!(
            KW(:levels => (1, 2, 3)),
        )
        @test_throws ArgumentError RecipesPipeline.preprocess_attributes!(KW(:levels => -3))
    end

    @testset "contour[f]" begin
        x = (-2π):0.1:(2π)
        y = (-π):0.1:π
        z = cos.(y) .* sin.(x')

        @testset "Incorrect input" begin
            @test_throws ArgumentError contour(x, y, z, levels = 1.0)
            @test_throws ArgumentError contour(x, y, z, levels = (1, 2, 3))
            @test_throws ArgumentError contour(x, y, z, levels = -3)
        end

        @testset "Default number" begin
            @test contour(x, y, z)[1][1].plotattributes[:levels] ==
                  Plots._series_defaults[:levels]
        end

        @testset "Number" begin
            @testset "$n contours" for n in (2, 5, 100)
                p = contour(x, y, z, levels = n)
                attr = p[1][1].plotattributes
                @test attr[:seriestype] == :contour
                @test attr[:levels] == n
            end
        end

        @testset "Range" begin
            levels = -1:0.5:1
            @test contour(x, y, z, levels = levels)[1][1].plotattributes[:levels] == levels
        end

        @testset "Set of levels" begin
            levels = [-1, 0.25, 0, 0.25, 1]
            @test contour(x, y, z, levels = levels)[1][1].plotattributes[:levels] == levels
        end
    end
end