orbits = {}
for line in io.lines(arg[1]) do
    a, b = line:match("(%w+)%)(%w+)")
    if not orbits[a] then
        orbits[a] = {}
    end
    table.insert(orbits[a], b)
end

print("Parsed...")

pos_you = nil
pos_san = nil
function getorbits(a, branches, depth)
    local value = depth
    if not orbits[a] then
        return value
    end
    local b = branches
    if #orbits[a] > 1 then
        b = {table.unpack(branches)}
        table.insert(b, {depth=depth, name=a})
    end
    for _, orbit in ipairs(orbits[a]) do
        if orbit == "YOU" then
            pos_you = {branches=branches, depth=depth}
        end
        if orbit == "SAN" then
            pos_san = {branches=branches, depth=depth}
        end

        value = value + getorbits(orbit, b, depth + 1)
    end
    return value
end

print("Part 1:", getorbits("COM", {}, 0))

commbranch = 1
while true do
    if pos_you.branches[commbranch] ~= pos_san.branches[commbranch] then
        break
    end
    commbranch = commbranch + 1
end
branch = pos_you.branches[commbranch - 1]
distance = pos_you.depth + pos_san.depth - branch.depth * 2
print("Part 2:", distance)