local deque = require "lib.utils.deque"

--- @param cur Vec3
--- @param to Vec3
--- @param acc Deque
local function greedy_trace_step(cur, to, acc)
    local lengthTable = {}
    for x = -1, 1 do
        for y = -1, 1 do
            local point = Vec3 { cur.x + x, cur.y + y }
            table.insert(lengthTable, { point, (point - to):length() })
        end
    end
    local min = lengthTable[1]
    for i = 2, #lengthTable do
        if lengthTable[i][2] < min[2] then min = lengthTable[i] end
    end
    local next = min[1]

    acc = acc:push_back(cur)
    if cur == to then
        return acc
    end
    return greedy_trace_step(next, to, acc)
end

--- @param from Vec3
--- @param to Vec3
--- @return Deque
local function trace(from, to)
    return greedy_trace_step(from, to, deque.new())
end

return trace