【界面UI】聊天输入框：字数校验与表情插入

---输入框创建与实时字数提示
function ChatInput.build(win)
    local input = GUI:TextInput_Create(win, "chat_input", 10, 10, 320, 30)
    local counter = GUI:Text_Create(win, "cnt", 340, 16, 12, "#999999", "0/60")
    ChatInput.input = input
    ChatInput.counter = counter
    ChatInput.limit = 60
end

---插入内容时校验字数
function ChatInput.insert(text)
    local cur = GUI:Text_getString(ChatInput.counter)
    local used = tonumber(cur:match("(%d+)/")) or 0
    if used + #text > ChatInput.limit * 3 then
        SL:ShowSystemTips("最多输入 60 个字")
        return false
    end
    return true
end

---表情面板：点选插入光标处
function ChatInput.pickEmoji(id)
    local face = "{f" .. id .. "}"
    ChatInput.insert(face)
    SL:ShowSystemTips("表情已插入")
end

---发送：预检后交给网络层
function ChatInput.send()
    local txt = ChatInput.getText()
    if txt == "" then return end
    SL:SendNetMsg(MSGID.CHAT_SEND, ChatInput.channel, txt, 0, "")
    ChatInput.clear()
end