【安全加密】敏感词过滤DFA：聊天词库的热更新与匹配实现

local root = {}
local function addWord(w)
    local node = root
    for i = 1, #w - 2, 3 do
        local ch = string.sub(w, i, i + 2)
        node[ch] = node[ch] or {}
        node = node[ch]
    end
    node.done = true
end
local function check(text)
    local n = #text
    for s = 1, n - 2, 3 do
        local node = root
        for e = s, n - 2, 3 do
            node = node[string.sub(text, e, e + 2)]
            if node == nil then break end
            if node.done then return true end
        end
    end
    return false
end

function chatCheck(actor, text)
    if check(text) then
        sendmsg(actor, 0, "发言包含违规内容，已被拦截")
        return false
    end
    return true
end