-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=41319
-- Id: 

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--|                                            http://fxcodebase.com |
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--|                                          mario.jemic@gmail.com   |
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--+------------------------------------------------------------------+

function Init()
    indicator:name("Didi index oscillator");
    indicator:description("Didi index oscillator");
    indicator:requiredSource(core.Tick);
    indicator:type(core.Oscillator);

    indicator.parameters:addGroup("Calculation");
    indicator.parameters:addInteger("CurtaPeriod", "Curta period", "", 3);
    indicator.parameters:addInteger("MediaPeriod", "Media period", "", 8);
    indicator.parameters:addInteger("LongaPeriod", "Longa period", "", 20);
    indicator.parameters:addString("Method", "Method", "", "MVA");
    indicator.parameters:addStringAlternative("Method", "MVA", "", "MVA");
    indicator.parameters:addStringAlternative("Method", "EMA", "", "EMA");
    indicator.parameters:addStringAlternative("Method", "KAMA", "", "KAMA");
    indicator.parameters:addStringAlternative("Method", "Wilder", "", "Wilder");
    indicator.parameters:addStringAlternative("Method", "LWMA", "", "LWMA");
    indicator.parameters:addStringAlternative("Method", "SineWMA", "", "SineWMA");
    indicator.parameters:addStringAlternative("Method", "TriMA", "", "TriMA");
    indicator.parameters:addStringAlternative("Method", "LSMA", "", "LSMA");
    indicator.parameters:addStringAlternative("Method", "SMMA", "", "SMMA");
    indicator.parameters:addStringAlternative("Method", "HMA", "", "HMA");
    indicator.parameters:addStringAlternative("Method", "ZeroLagEMA", "", "ZeroLagEMA");
    indicator.parameters:addStringAlternative("Method", "DEMA", "", "DEMA");
    indicator.parameters:addStringAlternative("Method", "T3", "", "T3");
    indicator.parameters:addStringAlternative("Method", "ITrend", "", "ITrend");
    indicator.parameters:addStringAlternative("Method", "Median", "", "Median");
    indicator.parameters:addStringAlternative("Method", "GeoMean", "", "GeoMean");
    indicator.parameters:addStringAlternative("Method", "REMA", "", "REMA");
    indicator.parameters:addStringAlternative("Method", "ILRS", "", "ILRS");
    indicator.parameters:addStringAlternative("Method", "IE/2", "", "IE/2");
    indicator.parameters:addStringAlternative("Method", "TriMAgen", "", "TriMAgen");
    indicator.parameters:addStringAlternative("Method", "JSmooth", "", "JSmooth");

    indicator.parameters:addGroup("Style");
    indicator.parameters:addColor("C_Up", "Curta up color", "Curta Up color", core.rgb(0, 255, 0));
	indicator.parameters:addColor("C_Down", "Curta down color", "Curta Down color", core.rgb(255, 0, 0));
 
 
    indicator.parameters:addColor("Lclr", "Longa color", "Longa color", core.rgb(0, 0, 255));
    indicator.parameters:addInteger("Lwidth", "Longa width", "Longa width", 1, 1, 5);
    indicator.parameters:addInteger("Lstyle", "Longa style", "Longa style", core.LINE_SOLID);
    indicator.parameters:setFlag("Lstyle", core.FLAG_LINE_STYLE);
end

local first;
local source = nil;
local CurtaPeriod;
local MediaPeriod;
local LongaPeriod;
local Method;
local C_MA, M_MA, L_MA;
local Curta=nil;
local Media=nil;
local Longa=nil;

function Prepare(nameOnly)
    source = instance.source;
    CurtaPeriod=instance.parameters.CurtaPeriod;
    MediaPeriod=instance.parameters.MediaPeriod;
    LongaPeriod=instance.parameters.LongaPeriod;
    Method=instance.parameters.Method;
    local name = profile:id() .. "(" .. source:name() .. ", " .. instance.parameters.CurtaPeriod .. ", " .. instance.parameters.MediaPeriod .. ", " .. instance.parameters.LongaPeriod .. ", " .. instance.parameters.Method .. ")";
    instance:name(name);
    if nameOnly then
        return;
    end
	assert(core.indicators:findIndicator("AVERAGES") ~= nil, "Please, download and install AVERAGES.LUA indicator");   
    C_MA = core.indicators:create("AVERAGES", source, Method, CurtaPeriod, false);
    M_MA = core.indicators:create("AVERAGES", source, Method, MediaPeriod, false);
    L_MA = core.indicators:create("AVERAGES", source, Method, LongaPeriod, false);
	
	 first = math.max(C_MA.DATA:first(),L_MA.DATA:first(),M_MA.DATA:first())
    Curta = instance:addStream("Curta", core.Bar, name .. ".Curta", "Curta", instance.parameters.C_Up, first);
 
   
    Longa = instance:addStream("Longa", core.Line, name .. ".Longa", "Longa", instance.parameters.Lclr, first);
    Longa:setWidth(instance.parameters.Lwidth);
    Longa:setStyle(instance.parameters.Lstyle);
	
	Curta:setPrecision(math.max(2, instance.source:getPrecision()));
 
	Longa:setPrecision(math.max(2, instance.source:getPrecision()));
end

function Update(period, mode)
   if period<first then
     return;
   end
   
    C_MA:update(mode);
    M_MA:update(mode);
    L_MA:update(mode);
    local Med=M_MA.DATA[period];
    if Med>0 then
     Curta[period]=(C_MA.DATA[period]/Med)-1;
     
     Longa[period]=(L_MA.DATA[period]/Med)-1;
    end
	
	if Curta[period]> 0 then
	Curta:setColor(period, instance.parameters.C_Up);
	else
	Curta:setColor(period, instance.parameters.C_Down);
	end
	
	
	
    
end