-- More information about this indicator can be found at:
-- https://fxcodebase.com/code/viewtopic.php?f=17&t=72795

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-- Indicator profile initialization routine
-- Defines indicator profile properties and indicator parameters
-- TODO: Add minimal and maximal value of numeric parameters and default color of the streams
function Init()
	indicator:name("SMI Min Max Oscillator")
	indicator:description("Shows the location of the  high/low price achieved between two SMI crosses")
	indicator:requiredSource(core.Bar)
	indicator:type(core.Oscillator)

 
    indicator.parameters:addGroup("Calculation");
    indicator.parameters:addInteger("Period_Q", "Period_Q", "Period_Q", 2);
    indicator.parameters:addInteger("Period_R", "Period_R", "Period_R", 8);
    indicator.parameters:addInteger("Period_S", "Period_S", "Period_S", 5);
    indicator.parameters:addInteger("Period_Signal", "Period_Signal", "Period_Signal", 5);
	
	indicator.parameters:addString("Method", "MA Method", "Method" , "EMA");
    indicator.parameters:addStringAlternative("Method", "MVA", "MVA" , "MVA");
    indicator.parameters:addStringAlternative("Method", "EMA", "EMA" , "EMA");
    indicator.parameters:addStringAlternative("Method", "LWMA", "LWMA" , "LWMA");
    indicator.parameters:addStringAlternative("Method", "TMA", "TMA" , "TMA");
    indicator.parameters:addStringAlternative("Method", "SMMA", "SMMA" , "SMMA");
    indicator.parameters:addStringAlternative("Method", "KAMA", "KAMA" , "KAMA");
    indicator.parameters:addStringAlternative("Method", "VIDYA", "VIDYA" , "VIDYA");
    indicator.parameters:addStringAlternative("Method", "WMA", "WMA" , "WMA");


	indicator.parameters:addBoolean("TrendFilter", "Use Trend Filter", "", true)

	indicator.parameters:addGroup("Style")
	indicator.parameters:addColor("Bottom", "Period Max Color", "", core.rgb(0, 255, 0))
	indicator.parameters:addColor("Top", "Period Min Color", "", core.rgb(255, 0, 0))
    indicator.parameters:addInteger("style", "Line Style", "", core.LINE_SOLID);
    indicator.parameters:setFlag("style", core.FLAG_LEVEL_STYLE);	
	indicator.parameters:addInteger("width", "Line Width", "", 3, 1, 5);
end

-- Indicator instance initialization routine
-- Processes indicator parameters and creates output streams
-- TODO: Refine the first period calculation for each of the output streams.
-- TODO: Calculate all constants, create instances all subsequent indicators and load all required libraries
-- Parameters block

local first
local source = nil
local Up, Down 
local Size 
local font
local Trend
local TrendFilter
local up,down;
local Top, Bottom;
function Prepare(nameOnly)
	TrendFilter = instance.parameters.TrendFilter
	Period_Q = instance.parameters.Period_Q
	Period_R = instance.parameters.Period_R
	Period_S = instance.parameters.Period_S
	Period_Signal = instance.parameters.Period_Signal
	Method = instance.parameters.Method
	Size = instance.parameters.Size
	Up = instance.parameters.Up
	Down = instance.parameters.Down

	source = instance.source

	local name =
		profile:id() ..
		"(" ..
			source:name() .. ", " .. source:barSize() .. ", " .. Period_Q .. ", " .. Period_R .. ", " .. Period_S .. ", " .. Period_Signal .. ", " .. Method .. ")"
	instance:name(name)

	if (nameOnly) then
		return
	end
	
    assert(core.indicators:findIndicator("SMI") ~= nil,  "SMI.lua indicator must be installed");	

	SMI = core.indicators:create("SMI", source, Period_Q ,Period_R, Period_S , Period_Signal , Method)
	first = SMI.SignalBuff:first()
	Trend = instance:addInternalStream(0, 0)

	Top = instance:addStream("Top" , core.Line, " Top"," Top",instance.parameters.Top, first);
	Top:setWidth(instance.parameters.width);
    Top:setStyle(instance.parameters.style);
    Top:setPrecision(math.max(2, source:getPrecision())); 
	
	Bottom = instance:addStream("Bottom" , core.Line, " Bottom"," Bottom",instance.parameters.Bottom, first);
	Bottom:setWidth(instance.parameters.width);
    Bottom:setStyle(instance.parameters.style);
    Bottom:setPrecision(math.max(2, source:getPrecision())); 
end

-- Indicator calculation routine
function Update(period, mode)
	period = period - 1
	SMI:update(mode)

	if SMI.DataBuff[period] > SMI.SignalBuff[period] and SMI.DataBuff[period - 1] <= SMI.SignalBuff[period - 1] then
		Trend[period] = 1
	end

	if SMI.DataBuff[period] < SMI.SignalBuff[period] and SMI.DataBuff[period - 1] >= SMI.SignalBuff[period - 1] then
		Trend[period] = -1
	end
	
	
	local Last=FindLast(period);
	
	if Last==0 
	then
	return;
	end
	
	local min, max, minpos, maxpos = mathex.minmax(source, Last, period - 1)
	
    Top[period]=max;
	Bottom[period]=min;
	
end


function FindLast(period)

    local from=0;

    for i= period-1, first, -1 do
	
	        if Trend[i] == 1 or Trend[i] == -1 then
			from = i;
			break
		end
	end
	
   return from;
end

 --+------------------------------------------------------------------------------------------------+
--|                                                                    We appreciate your support. | 
--+------------------------------------------------------------------------------------------------+
--|                                                               Paypal: https://goo.gl/9Rj74e    |
--|                                                             Patreon :  https://goo.gl/GdXWeN   |  
--+------------------------------------------------------------------------------------------------+
--|                                                                   Developed by : Mario Jemic   |                    
--|                                                                       mario.jemic@gmail.com    |
--|                                                        https://AppliedMachineLearning.systems  |
--|                                                                       https://mario-jemic.com/ |
--+------------------------------------------------------------------------------------------------+