狀態模式lua實現

--[[
	狀態模式(State Pattern)是設計模式的一種，屬於行為模式。
	適用場景：
	1.一個對象的行為取決於它的狀態，並且它必須在運行時刻根據狀態改變它的行為。
	2.一個操作中含有龐大的多分支結構，並且這些分支決定於對象的狀態。

]]--

Work = {}

function Work:new(o,s)
	o = o or {}
	setmetatable(o,self)
	self.__index = self
	o.hour = 0
	o.currentstate = s
	return o;
end

function Work:SetTime(h)
	self.hour = h
end

function Work:GetTime()
	return self.hour
end

function Work:SetState(s)
	self.currentstate = s
end

function Work:WriteProgram()
	self.currentstate:WriteProgram(self)
end

State = {}

function State:new(o)
	o = o or {}
	setmetatable(o,self)
	self.__index = self
	return o;
end

MorningState = State:new()

function MorningState:WriteProgram(w)
	if w.hour < 12 and w.hour >= 9 then
		print("早上寫代碼，精神百倍")
	else
		w:SetState(NoonState:new())
		w:WriteProgram()
	end
end

NoonState = State:new()

function NoonState:WriteProgram(w)
	if w.hour < 14 and w.hour >= 12 then
		print("中午寫代碼，犯困了，先小睡一下再說")
	else
		w:SetState(AfternoonState:new())
		w:WriteProgram()
	end
end

AfternoonState = State:new()

function AfternoonState:WriteProgram(w)
	if w.hour < 17 and w.hour >= 14 then
		print("下午寫代碼, 精神充足")
	else
		w:SetState(EveningState:new())
		w:WriteProgram()
	end
end

EveningState = State:new()

function EveningState:WriteProgram(w)
	if w.hour < 20 and w.hour >=17 then
		print("傍晚寫代碼，有點累，但還是繼續")
	else
		w:SetState(NightState:new())
		w:WriteProgram()
	end
end

NightState = State:new()

function NightState:WriteProgram(w)
	if w.hour < 22 and w.hour >= 20 then
		print("晚上寫代碼，苦逼啊")
	else
		w:SetState(MidnightState:new())
		w:WriteProgram()
	end
end

MidnightState = State:new()

function MidnightState:WriteProgram(w)
	if w.hour < 9 or w.hour >= 22 then
		print("深夜寫代碼，尼瑪，先睡醒了再說")
	else
		w:SetState(MorningState:new())
		w:WriteProgram()
	end
end

w = Work:new(nil,MorningState:new())
w:SetTime(21)
w:WriteProgram()

w:SetTime(18)
w:WriteProgram()

w:SetTime(10)
w:WriteProgram()

w:SetTime(13)
w:WriteProgram()

w:SetTime(15)
w:WriteProgram()

w:SetTime(23)
w:WriteProgram()