-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=36543

--+------------------------------------------------------------------+
--|                               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  |  
--+------------------------------------------------------------------+

-- 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("Point of Balance");
    indicator:description("Point of Balance");
    indicator:requiredSource(core.Bar);
    indicator:type(core.Indicator);
    indicator.parameters:addGroup("Calculation");
    indicator.parameters:addInteger("Period", "Period", "Period", 14);
	indicator.parameters:addGroup("Style");
    indicator.parameters:addColor("BL_color", "Color of BL", "Color of BL", core.rgb(255, 0, 0));
	indicator.parameters:addInteger("width1", "Line width", "", 1, 1, 5);
    indicator.parameters:addInteger("style1", "Line style", "", core.LINE_SOLID);
    indicator.parameters:setFlag("style1", core.FLAG_LINE_STYLE);
    indicator.parameters:addColor("POB_color", "Color of POB", "Color of POB", core.rgb(0, 0, 255));
	indicator.parameters:addInteger("width2", "Line width", "", 1, 1, 5);
    indicator.parameters:addInteger("style2", "Line style", "", core.LINE_SOLID);
    indicator.parameters:setFlag("style2", core.FLAG_LINE_STYLE);
    indicator.parameters:addColor("BR_color", "Color of BR", "Color of BR", core.rgb(0, 255, 0));
	indicator.parameters:addInteger("width3", "Line width", "", 1, 1, 5);
    indicator.parameters:addInteger("style3", "Line style", "", core.LINE_SOLID);
    indicator.parameters:setFlag("style3", core.FLAG_LINE_STYLE);
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 Period;

local first;
local source = nil;

-- Streams block
local BL = nil;
local POB = nil;
local BR = nil;

-- Routine
function Prepare(nameOnly)
    Period = instance.parameters.Period;
    source = instance.source;
    first = source:first()+Period;

    local name = profile:id() .. "(" .. source:name() .. ", " .. tostring(Period) .. ")";
    instance:name(name);

    if   (nameOnly) then
        return;
    end
        BL = instance:addStream("BL", core.Line, name .. ".BL", "BL", instance.parameters.BL_color, first);
		BL:setWidth(instance.parameters.width1);
        BL:setStyle(instance.parameters.style1);
        POB = instance:addStream("POB", core.Line, name .. ".POB", "POB", instance.parameters.POB_color, first);
		POB:setWidth(instance.parameters.width2);
        POB:setStyle(instance.parameters.style2);
        BR = instance:addStream("BR", core.Line, name .. ".BR", "BR", instance.parameters.BR_color, first);
		BR:setWidth(instance.parameters.width3);
        BR:setStyle(instance.parameters.style3);
     
end

-- Indicator calculation routine
-- TODO: Add your code for calculation output values
function Update(period)
    if period < first   then
	return;
	end
	
	local min1, max1;
	local min2, max2;
	min1, max1= mathex.minmax(source.high, period-Period+1, period);
        BL[period] = (min1+max1)/2;
       
	min2, max2= mathex.minmax(source.low, period-Period+1, period);
	
	
	    BR[period] =  (min2+max2)/2;
		 POB[period] = ((BL[period]-BR[period])/2)+ BR[period];
       
    
end