local hudHandlers = {}

function eregions:registerHudHandler (handler)
    table.insert (hudHandlers, handler)
end

function eregions:getExternalHudEntries (pos)
    local eregions = {}
    for _, func in pairs(hudHandlers) do
        func (pos, eregions)
    end
    return eregions
end

function eregions:getERegionsAtPos (pos)
    local res = {}

    if self.store then
        local a = self.store:get_areas_for_pos (pos, false, true)
        for store_id, store_eregion in pairs (a) do
            local id = tonumber (store_eregion.data)
            res [id] = self.eregions [id]
        end
    else
        local px, py, pz = pos.x, pos.y, pos.z

        for id, eregion in pairs (self.eregions) do
            local ap1, ap2 = eregion.pos1, eregion.pos2

            if (px >= ap1.x and px <= ap2.x) and
               (py >= ap1.y and py <= ap2.y) and
               (pz >= ap1.z and pz <= ap2.z) then
                res [id] = eregion
            end
        end
    end
    return res
end

function eregions:has_feature (pos, name)
    for _, eregion in pairs (self:getERegionsAtPos (pos)) do
        if eregion.efeature == name then return true end
    end
    return false
end

function eregions:getNodeEFeatures (pos)
    local efeatures = {}
    for _, eregion in pairs(self:getERegionsAtPos (pos)) do
        table.insert(efeatures, eregion.efeature)
    end
    return efeatures
end