module UKP

using JuMP
import JSON

const ROOT = joinpath(@__DIR__, "UKP")

function get_next_line(io)
    while !eof(io)
        line = readline(io)
        if isempty(line) || startswith(line, "#")
            continue
        end
        return line
    end
    return nothing
end

function build_model(filename)
    C, w, W = open(filename, "r") do io
        N = parse(Int, get_next_line(io))
        P = parse(Int, get_next_line(io))
        K = parse(Int, get_next_line(io))
        @assert K == 1
        C = zeros(P, N)
        for p in 1:P
            for i in 1:N
                C[p, i] = parse(Float64, get_next_line(io))
            end
        end
        w = zeros(N)
        for i in 1:N
            w[i] = parse(Float64, get_next_line(io))
        end
        W = parse(Float64, get_next_line(io))
        return (C, w, W)
    end
    P, N = size(C)
    model = Model()
    @variable(model, x[1:N], Bin)
    @constraint(model, w' * x <= W)
    @objective(model, Max, C * x)
    return model
end

function main()
    instances = ["2KP50-11", "2KP50-50", "2KP50-92", "2KP100-50"]
    for instance in instances
        dat_filename = joinpath(ROOT, "instances", "1A", instance * ".dat")
        model = build_model(dat_filename)
        write_to_file(model, joinpath("instances/models", instance * ".mof.json"))
        x_filename = joinpath(ROOT, "X", instance * ".max")
        solutions = Dict{String,Any}[]
        open(x_filename, "r") do io
            for line in readlines(io)
                items = split(line)
                X = ifelse.(codeunits(items[end]) .== UInt8('1'), 1, 0)
                Y = parse.(Float64, items[1:end-1])
                push!(solutions, Dict("X" => X, "Y" => Y))
            end
        end
        solution_filename = joinpath("instances/solutions", instance * ".json")
        write(solution_filename, JSON.json(solutions))
    end
    return
end

end  # module UKP

UKP.main()