-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=10401

--+------------------------------------------------------------------+
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--|                                            http://fxcodebase.com |
--+------------------------------------------------------------------+
--|                                      Developed by : Mario Jemic  |                    
--|                                          mario.jemic@gmail.com   |
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--+------------------------------------------------------------------+
function Init()
    indicator:name("Fibo Trigger indicator");
    indicator:description("Fibo Trigger indicator");
    indicator:requiredSource(core.Bar);
    indicator:type(core.Indicator);

    indicator.parameters:addGroup("Calculation");
    indicator.parameters:addInteger("Period", "Period", "", 10);
    indicator.parameters:addString("FiboLevel", "Fibo level", "Fibo level", "0.236");
    indicator.parameters:addStringAlternative("FiboLevel", "0.236", "", "0.236");
    indicator.parameters:addStringAlternative("FiboLevel", "0.382", "", "0.382");
    indicator.parameters:addStringAlternative("FiboLevel", "0.500", "", "0.500");
    indicator.parameters:addStringAlternative("FiboLevel", "0.618", "", "0.618");
    indicator.parameters:addStringAlternative("FiboLevel", "0.762", "", "0.762");

    indicator.parameters:addGroup("Style");
    indicator.parameters:addColor("UPclr", "UP Color", "UP Color", core.rgb(0, 255, 0));
    indicator.parameters:addColor("DNclr", "DN Color", "DN Color", core.rgb(255, 255, 0));
    indicator.parameters:addInteger("DotSize", "Dot size", "Dot size", 3, 1, 5);
end

local first;
local source = nil;
local Period;
local FiboLevel;
local trend;
local FT=nil;

function Prepare(nameOnly)   
    source = instance.source;
    Period=instance.parameters.Period;
    FiboLevel=tonumber(instance.parameters.FiboLevel);
    first = source:first()+Period;
    trend = instance:addInternalStream(first, 0);
    local name = profile:id() .. "(" .. source:name() .. ", " .. instance.parameters.Period .. ", " .. instance.parameters.FiboLevel .. ")";
    instance:name(name);
	
	if   (nameOnly) then
        return;
    end
	
	
    FT = instance:addStream("FT", core.Dot, name .. ".Fibo trigger", "Fibo trigger", instance.parameters.UPclr, first);
    FT:setWidth(instance.parameters.DotSize);
end

function Update(period, mode)
   if (period>first) then
    local MaxHigh=mathex.max(source.high,core.rangeTo(period,Period));
    local MinLow=mathex.min(source.low,core.rangeTo(period,Period));
    local range=MaxHigh-MinLow;
    trend[period]=trend[period-1];
    if source.open[period]>source.close[period] then
     if range*FiboLevel>=source.close[period]-MinLow then
      trend[period]=1; 
     end
    else
     if range*FiboLevel>=MaxHigh-source.close[period] then
      trend[period]=-1;
     end
    end
    
    if trend[period-1]==1 and trend[period]==-1 then
     FT[period]=source.low[period];
     FT:setColor(period,instance.parameters.UPclr);
    elseif trend[period-1]==-1 and trend[period]==1 then 
     FT[period]=source.high[period];
     FT:setColor(period,instance.parameters.DNclr);
    end
   elseif period==first then
    trend[period]=0; 
   end 
end