-- Id: 8264
-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=28055

--+------------------------------------------------------------------+
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--|                                            http://fxcodebase.com |
--+------------------------------------------------------------------+
--|                                      Developed by : Mario Jemic  |
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--+------------------------------------------------------------------+
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--+------------------------------------------------------------------+
function Init()
    indicator:name("Trend Intensity Index ");
    indicator:description("Trend Intensity Index ");
    indicator:requiredSource(core.Tick);
    indicator:type(core.Oscillator);
    indicator.parameters:addGroup("Calculation");	
	
    indicator.parameters:addInteger("Period", "Period", "Period", 30);
    indicator.parameters:addInteger("MAPeriod", "Ma Period", "Period", 60);
	indicator.parameters:addString("Method", "MA Method", "Method" , "MVA");
    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:addGroup("Style");	
    indicator.parameters:addColor("TII_color", "Color of TII", "Color of TII", core.rgb(255, 0, 0));
	indicator.parameters:addInteger("width", "Line width", "", 1, 1, 5);
    indicator.parameters:addInteger("style", "Line style", "", core.LINE_SOLID);
    indicator.parameters:setFlag("style", core.FLAG_LINE_STYLE);
	
	
	indicator.parameters:addGroup("OB/OS Levels");	
    indicator.parameters:addDouble("overbought", "Overbought Level","", 80);
    indicator.parameters:addDouble("oversold","Oversold Level","", 20);
	indicator.parameters:addColor("level_overboughtsold_color", "Line Color","", core.rgb(128, 128, 128));
    indicator.parameters:addInteger("level_overboughtsold_width","Line width","", 1, 1, 5);
    indicator.parameters:addInteger("level_overboughtsold_style", "Line Style","", core.LINE_SOLID);
    indicator.parameters:setFlag("level_overboughtsold_style", core.FLAG_LEVEL_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 MAPeriod;
local Period;
local Method;
local first;
local source = nil;
local MA;
local Up, Down;
-- Streams block
local TII = nil;

-- Routine
function Prepare(nameOnly)
    MAPeriod = instance.parameters.MAPeriod;
	Method = instance.parameters.Method;
    Period = instance.parameters.Period;
    source = instance.source;

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

    if (not (nameOnly)) then
    assert(core.indicators:findIndicator(Method) ~= nil, Method .. " indicator must be installed");
        MA = core.indicators:create(Method, source, MAPeriod);
        first = MA.DATA:first();
        
        Up = instance:addInternalStream(first, 0);
        Down = instance:addInternalStream(first, 0);
        TII = instance:addStream("TII", core.Line, name, "TII", instance.parameters.TII_color, first +Period);
    TII:setPrecision(math.max(2, instance.source:getPrecision()));
		TII:setWidth(instance.parameters.width);
        TII:setStyle(instance.parameters.style);
		TII:addLevel(instance.parameters.oversold, instance.parameters.level_overboughtsold_style, instance.parameters.level_overboughtsold_width, instance.parameters.level_overboughtsold_color);
		TII:addLevel(instance.parameters.overbought, instance.parameters.level_overboughtsold_style, instance.parameters.level_overboughtsold_width, instance.parameters.level_overboughtsold_color);    
    end
end

-- Indicator calculation routine
-- TODO: Add your code for calculation output values
function Update(period, mode)

    MA:update(mode);
	
    if period < first   then
	return;
	end
	
	if source[period] > MA.DATA[period] then
	Up[period]= source[period] - MA.DATA[period];
	Down[period]=0;
	elseif source[period] < MA.DATA[period] then
	Up[period]=0;
	Down[period]= MA.DATA[period] - source[period];
	end
	
	if period < first +Period  then
	return;
	end
	
	local POS=mathex.sum (Up, period-Period+1, period);
	local NEG=mathex.sum (Down, period-Period+1, period);
	
	TII[period] = 100 * (POS) / (POS + NEG)
	 
	 
    
end