-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=2527

--+------------------------------------------------------------------+
--|                               Copyright © 2018, Gehtsoft USA LLC | 
--|                                            http://fxcodebase.com |
--+------------------------------------------------------------------+
--|                                      Developed by : Mario Jemic  |                    
--|                                          mario.jemic@gmail.com   |
--+------------------------------------------------------------------+
--|                                 Support our efforts by donating  | 
--|                                    Paypal: https://goo.gl/9Rj74e |
--+------------------------------------------------------------------+
--|                                Patreon :  https://goo.gl/GdXWeN  |  
--|                    BitCoin : 15VCJTLaz12Amr7adHSBtL9v8XomURo9RF  |  
--|                BitCoin Cash: 1BEtS465S3Su438Kc58h2sqvVvHK9Mijtg  | 
--|           Ethereum : 0x8C110cD61538fb6d7A2B47858F0c0AaBd663068D  |  
--|                   LiteCoin : LLU8PSY2vsq7B9kRELLZQcKf5nJQrdeqwD  |  
--+------------------------------------------------------------------+


-- original version: Jason Robinson (jnrtrading)
-- http://codebase.mql4.com/4725

-- Indicator profile initialization routine
-- Defines indicator profile properties and indicator parameters
function Init()
    indicator:name("SuperTrend Indicator (dot version)");
    indicator:description("The indicator (dot version) displays the buying and selling with the colors. The indicator is initially developed by Jason Robinson for MT4");
    indicator:requiredSource(core.Bar);
    indicator:type(core.Indicator);

	indicator.parameters:addGroup("Calculation");  
    indicator.parameters:addInteger("N", "Number of periods", "No description", 10);
    indicator.parameters:addDouble("M", "Multiplier", "No description", 1.5);
	
	indicator.parameters:addGroup("Style");  
    indicator.parameters:addColor("UP_color", "Color of UP", "Color of UP", core.rgb(0, 255, 0));
    indicator.parameters:addColor("DN_color", "Color of DN", "Color of DN", core.rgb(255, 0, 0));
    indicator.parameters:addInteger("width", "Line width", "Line width", 3, 1, 5);
	
	indicator.parameters:addGroup("Selector"); 
	
	indicator.parameters:addBoolean("Show", "Show Historical", "", true);
	
end

-- Indicator instance initialization routine
-- Processes indicator parameters and creates output streams
-- Parameters block
local N;
local M;

local first;
local source = nil;
local ATR = nil;

-- Streams block
local TrUP = nil;
local TrDN = nil;
local UP = nil;
local DN = nil;
local TR = nil;

local Show;

-- Routine
function Prepare()
    N = instance.parameters.N;
    M = instance.parameters.M;
	Show= instance.parameters.Show;
    source = instance.source;
    ATR = core.indicators:create("ATR", source, N);
    first = ATR.DATA:first();
    local name = profile:id() .. "(" .. source:name() .. "," .. N .. "," .. M .. ")";
    instance:name(name);
    UP = instance:addInternalStream(first, 0);
    DN = instance:addInternalStream(first, 0);
    TR = instance:addInternalStream(first, 0);
    TrUP = instance:addStream("UP", core.Dot, name .. ".UP", "UP", instance.parameters.UP_color, first);
    TrDN = instance:addStream("DN", core.Dot, name .. ".DN", "DN", instance.parameters.DN_color, first);
    TrUP:setWidth(instance.parameters.width);
    TrDN:setWidth(instance.parameters.width);
end

-- Indicator calculation routine
function Update(period, mode)
    ATR:update(mode);
    TR[period] = 1;
    if period >= first then
        local median, atr;
        atr = ATR.DATA[period];
        median = (source.high[period] + source.low[period]) / 2;
        UP[period] = median + atr * M;
        DN[period] = median - atr * M;

        if period >= first + 1 then
            if source.close[period] > UP[period - 1] then
                TR[period] = 1;
            elseif source.close[period] < DN[period - 1] then
                TR[period] = -1;
            else
                TR[period] = TR[period - 1];
            end

            local flag, flagh;

            if TR[period] < 0 and TR[period - 1] > 0 then
               flag = 1;
            else
               flag = 0;
            end

            if TR[period] > 0 and TR[period - 1] < 0 then
               flagh = 1;
            else
               flagh = 0;
            end

            if TR[period] > 0 and DN[period] < DN[period - 1] then
                DN[period] = DN[period - 1];
            end

            if TR[period] < 0 and UP[period] > UP[period - 1] then
                UP[period] = UP[period - 1];
            end

            if flag == 1 then
                UP[period] = median + atr * M;
            end

            if flagh == 1 then
                DN[period] = median - atr * M;
            end

			if Show then      
				if TR[period] == 1 then
					TrUP[period] = DN[period];
					TrDN[period] = nil;
				end

				if TR[period] == -1 then
					TrDN[period] = UP[period];
					TrUP[period] = nil;
				end
			else
			  
			   if period < source:size()-1 then
			   return;
			   end
			   
			   TrUP[period-1]=nil;
			   TrDN[period-1]=nil;
			   
			
			   if TR[period] == 1 then
					TrUP[period] = DN[period];
					TrDN[period] = nil;
				end

				if TR[period] == -1 then
					TrDN[period] = UP[period];
					TrUP[period] = nil;
				end
			end
			
        end
    end
end