local positions = {}


local ObjectRefmetatable

local offset = vector.new(0,0.01,0)

-- table of nodes to ignore when players move through them example air=true
local ignorenodes = {} 

local function checkray(ray)
    -- returns intersection_point or nil if not blocked
    local next = ray:next()
    local blocked = false
    while next ~= nil and blocked == false do
        local nname = minetest.get_node(next.under).name
        if next.under and (ignorenodes[nname] ~= true) and (next.above ~= next.under) then --right here check node stuff like can_collide and different nodebox vs collisionbox
            blocked = true
            return next.intersection_point
        end
        next = ray:next()
    end
end

minetest.register_on_mods_loaded(function()
    for key, value in pairs(minetest.registered_nodes) do
        if value.walkable == false then
            ignorenodes[key] = true
        end
        local selbox = value.selection_box or value.node_box
        local colbox = value.collision_box or value.node_box
        --print(dump(value.selection_box),dump(value.collision_box))
        if (selbox ~= nil and colbox ~= nil)
        and(dump(selbox) ~= dump(colbox)) then
            ignorenodes[key] = true
        end
    end
end)

minetest.register_globalstep(function(dtime)
    for index, value in ipairs(minetest.get_connected_players()) do
        local name = value:get_player_name()
        if not minetest.check_player_privs(name, "noclip") then
            local pos = value:get_pos() + offset
            local lastpos
            if positions[name] == nil then
                positions[name] = pos
            end
            lastpos = positions[name]
            local between = vector.new(lastpos.x,pos.y,lastpos.z)
            if pos.y < lastpos.y then
                between = vector.new(pos.x,lastpos.y,pos.z)
            end
            local blocked
            local ray = Raycast(positions[name], between, false, false)
            local ray2 = Raycast(between, pos, false, false)
            if positions[name] ~= between then
                blocked = checkray(ray)
            end
            if not blocked then
                blocked = checkray(ray2)
            end
            if blocked then
                value:old_set_pos(positions[name] - offset)
            else
                positions[name] = pos
            end
        end
    end
end)

local function patchobj(ObjectRef)
    ObjectRefmetatable = getmetatable(ObjectRef)
    local gp = ObjectRefmetatable.set_pos
    local mt = ObjectRefmetatable.move_to
    local newgp = function (self,pos, ...)
        if self:is_player() then
            positions[self:get_player_name()] = nil
            print("player teleprotd")
        end
        gp(self,pos,...)
    end
    local newmt = function (self,pos, ...)
        if self:is_player() then
            positions[self:get_player_name()] = nil
            print("player teleprotd")
        end
        mt(self,pos,...)
    end
    ObjectRefmetatable.set_pos = newgp
    ObjectRefmetatable.old_set_pos = gp
    ObjectRefmetatable.move_to = newmt
    ObjectRefmetatable.old_move_to = mt
end

minetest.register_on_joinplayer(function(ObjectRef, last_login)
    if ObjectRefmetatable then
        return
    end
    patchobj(ObjectRef)
end)