# UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
# Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
# Released under the modified BSD license. See COPYING.md for more details.

using UnitCommitment, Test, LinearAlgebra

@testset "Sensitivity" begin
    @testset "Susceptance matrix" begin
        instance = UnitCommitment.read_benchmark("test/case14")
        actual = UnitCommitment._susceptance_matrix(instance.lines)
        @test size(actual) == (20, 20)
        expected = Diagonal([29.5,  7.83,  8.82, 9.9,  10.04,
                             10.2,  41.45, 8.35, 3.14, 6.93,
                             8.77,  6.82,  13.4, 9.91, 15.87,
                             20.65, 6.46,  9.09, 8.73, 5.02])
        @test round.(actual, digits=2) == expected
    end
    
    @testset "Reduced incidence matrix" begin
        instance = UnitCommitment.read_benchmark("test/case14")
        actual = UnitCommitment._reduced_incidence_matrix(
            lines=instance.lines,
            buses=instance.buses,
        )
        @test size(actual) == (20, 13)
        @test actual[1,   1]  == -1.0
        @test actual[3,   1]  ==  1.0
        @test actual[4,   1]  ==  1.0
        @test actual[5,   1]  ==  1.0
        @test actual[3,   2]  == -1.0
        @test actual[6,   2]  ==  1.0
        @test actual[4,   3]  == -1.0
        @test actual[6,   3]  == -1.0
        @test actual[7,   3]  ==  1.0
        @test actual[8,   3]  ==  1.0
        @test actual[9,   3]  ==  1.0
        @test actual[2,   4]  == -1.0
        @test actual[5,   4]  == -1.0
        @test actual[7,   4]  == -1.0
        @test actual[10,  4]  ==  1.0
        @test actual[10,  5]  == -1.0
        @test actual[11,  5]  ==  1.0
        @test actual[12,  5]  ==  1.0
        @test actual[13,  5]  ==  1.0
        @test actual[8,   6]  == -1.0
        @test actual[14,  6]  ==  1.0
        @test actual[15,  6]  ==  1.0
        @test actual[14,  7]  == -1.0
        @test actual[9,   8]  == -1.0
        @test actual[15,  8]  == -1.0
        @test actual[16,  8]  ==  1.0
        @test actual[17,  8]  ==  1.0
        @test actual[16,  9]  == -1.0
        @test actual[18,  9]  ==  1.0
        @test actual[11, 10]  == -1.0
        @test actual[18, 10]  == -1.0
        @test actual[12, 11]  == -1.0
        @test actual[19, 11]  ==  1.0
        @test actual[13, 12]  == -1.0
        @test actual[19, 12]  == -1.0
        @test actual[20, 12]  ==  1.0
        @test actual[17, 13]  == -1.0
        @test actual[20, 13]  == -1.0
    end
    
    @testset "Injection Shift Factors (ISF)" begin
        instance = UnitCommitment.read_benchmark("test/case14")
        actual = UnitCommitment._injection_shift_factors(
            lines=instance.lines,
            buses=instance.buses,
        )
        @test size(actual) == (20, 13)
        @test round.(actual, digits=2) == [
            -0.84 -0.75 -0.67 -0.61 -0.63 -0.66 -0.66 -0.65 -0.65 -0.64 -0.63 -0.63 -0.64;
            -0.16 -0.25 -0.33 -0.39 -0.37 -0.34 -0.34 -0.35 -0.35 -0.36 -0.37 -0.37 -0.36;
             0.03 -0.53 -0.15 -0.1  -0.12 -0.14 -0.14 -0.14 -0.13 -0.13 -0.12 -0.12 -0.13;
             0.06 -0.14 -0.32 -0.22 -0.25 -0.3  -0.3  -0.29 -0.28 -0.27 -0.25 -0.26 -0.27;
             0.08 -0.07 -0.2  -0.29 -0.26 -0.22 -0.22 -0.22 -0.23 -0.25 -0.26 -0.26 -0.24;
             0.03  0.47 -0.15 -0.1  -0.12 -0.14 -0.14 -0.14 -0.13 -0.13 -0.12 -0.12 -0.13;
             0.08  0.31  0.5  -0.3  -0.03  0.36  0.36  0.28  0.23  0.1  -0.0   0.02  0.17;
             0.0   0.01  0.02 -0.01 -0.22 -0.63 -0.63 -0.45 -0.41 -0.32 -0.24 -0.25 -0.36;
             0.0   0.01  0.01 -0.01 -0.12 -0.17 -0.17 -0.26 -0.24 -0.18 -0.14 -0.14 -0.21;
            -0.0  -0.02 -0.03  0.02 -0.66 -0.2  -0.2  -0.29 -0.36 -0.5  -0.63 -0.61 -0.43;
            -0.0  -0.01 -0.02  0.01  0.21 -0.12 -0.12 -0.17 -0.28 -0.53  0.18  0.15 -0.03;
            -0.0  -0.0  -0.0   0.0   0.03 -0.02 -0.02 -0.03 -0.02  0.01 -0.52 -0.17 -0.09;
            -0.0  -0.01 -0.01  0.01  0.11 -0.06 -0.06 -0.09 -0.05  0.02 -0.28 -0.59 -0.31;
            -0.0  -0.0  -0.0  -0.0  -0.0  -0.0  -1.0  -0.0  -0.0  -0.0  -0.0  -0.0   0.0 ;
             0.0   0.01  0.02 -0.01 -0.22  0.37  0.37 -0.45 -0.41 -0.32 -0.24 -0.25 -0.36;
             0.0   0.01  0.02 -0.01 -0.21  0.12  0.12  0.17 -0.72 -0.47 -0.18 -0.15  0.03;
             0.0   0.01  0.01 -0.01 -0.14  0.08  0.08  0.12  0.07 -0.03 -0.2  -0.24 -0.6 ;
             0.0   0.01  0.02 -0.01 -0.21  0.12  0.12  0.17  0.28 -0.47 -0.18 -0.15  0.03;
            -0.0  -0.0  -0.0   0.0   0.03 -0.02 -0.02 -0.03 -0.02  0.01  0.48 -0.17 -0.09;
            -0.0  -0.01 -0.01  0.01  0.14 -0.08 -0.08 -0.12 -0.07  0.03  0.2   0.24 -0.4  ]
    end

    @testset "Line Outage Distribution Factors (LODF)" begin
        instance = UnitCommitment.read_benchmark("test/case14")
        isf_before = UnitCommitment._injection_shift_factors(
            lines=instance.lines,
            buses=instance.buses,
        )
        lodf = UnitCommitment._line_outage_factors(
            lines=instance.lines,
            buses=instance.buses,
            isf=isf_before,
        )
        for contingency in instance.contingencies
            for lc in contingency.lines
                prev_susceptance = lc.susceptance
                lc.susceptance = 0.0
                isf_after =  UnitCommitment._injection_shift_factors(
                    lines=instance.lines,
                    buses=instance.buses,
                )
                lc.susceptance = prev_susceptance
                for lm in instance.lines
                    expected = isf_after[lm.offset, :]
                    actual = isf_before[lm.offset, :] +
                                 lodf[lm.offset, lc.offset] * isf_before[lc.offset, :]
                    @test norm(expected - actual) < 1e-6
                end
            end
        end
    end
end