#!/usr/bin/env julia

using Test

function parse_line_ranges(line)
  parts = split(line, ',')
  ranges = Vector{UnitRange{Int64}}()
  for p in parts
    start, stop = split(p, '-', limit=2)
    prange = UnitRange(parse(Int64, start), parse(Int64, stop))
    push!(ranges, prange)
  end
  return ranges
end

function line_range_contained(line)
  ranges = parse_line_ranges(line)
  inter = intersect(ranges[1], ranges[2])
  return (inter == ranges[1] || inter == ranges[2])
end

function line_range_overlap(line)
  ranges = parse_line_ranges(line)
  inter = intersect(ranges[1], ranges[2])
  return length(inter) > 0
end

function count_range_contained(infile)
  rsum = 0

  open(infile, "r") do io
    for line in eachline(io)
      if line_range_contained(line)
        rsum += 1
      end
    end
  end

  return rsum
end

function count_range_overlap(infile)
  osum = 0

  open(infile, "r") do io
    for line in eachline(io)
      if line_range_overlap(line)
        osum += 1
      end
    end
  end

  return osum
end

function test()
  @testset "elf cleaning contained" verbose=true begin
    @test count_range_contained("example.txt") == 2
    @test count_range_contained("input.txt") == 500
  end
  @testset "elf cleaning overlap" verbose=true begin
    @test count_range_overlap("example.txt") == 4
    @test count_range_overlap("input.txt") == 815
  end
end

function main()
  if size(ARGS, 1) == 0
    test()
  else
    infile = ARGS[1]
    println("infile = ", infile)
    println("bad assignments: ", count_range_contained(infile))
  end
end

main()