-- More information about this indicator can be found at:
-- http://fxcodebase.com/code/viewtopic.php?f=17&t=65729

--+------------------------------------------------------------------+
--|                               Copyright © 2018, Gehtsoft USA LLC |
--|                                            http://fxcodebase.com |
--+------------------------------------------------------------------+
--|                                      Developed by : Mario Jemic  |
--|                                          mario.jemic@gmail.com   |
--+------------------------------------------------------------------+
--|                                 Support our efforts by donating  |
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--+------------------------------------------------------------------+

local length, price_smoothing, signal_smoothing
local first
local source = nil
local MVA, EMA1, EMA2, EMA3
local vpc, signal, indi_source, UP_color, DN_color, hist
local UP, UPDOWN, DOWNUP, DOWN

local indi_alerts = {};
indi_alerts.Version = "2.1";
indi_alerts.inverted_arrows = false;
local alerts = 
{ 
    {
        Stage = 102,
        UpCondition = function (period)
            if period < 0 or not vpc:hasData(period - 1) then
                return false;
            end
            return core.crossesOver(vpc, signal, period);
        end,
        DownCondition = function (period)
            if period < 0 or not vpc:hasData(period - 1) then
                return false;
            end
            return core.crossesUnder(vpc, signal, period);
        end,
        FormatMessage = function(source, period, level, label, isUp)
            return string.format(
                "Label: %s\013\010" ..
                "Instrument: %s\013\010" ..
                "Time Frame: %s\013\010" ..
                "Price: %s\013\010" .. 
                "Date: %s", 
                isUp and (label .. " Bull pattern") or (label .. " Bear pattern"), 
                source:instrument(), 
                source:barSize(), 
                win32.formatNumber(source.close[NOW], false, source:getPrecision()), 
                core.formatDate(core.now()));
        end,
        OnChange = true,
        Name = "VPC/Signal cross"
    }
};

function Init()
	indicator:name("Volume Price Change")
	indicator:description("")
	indicator:requiredSource(core.Tick)
	indicator:type(core.Oscillator)

	indicator.parameters:addGroup("Calculation")
	indicator.parameters:addInteger("length", "Period", "", 15, 2, 2000)
	indicator.parameters:addInteger("price_smoothing", "Price Smoothing", "", 15)
	indicator.parameters:addInteger("signal_smoothing", "Signal Smoothing", "", 15)

	indicator.parameters:addGroup("Style")
	indicator.parameters:addColor("color1", "Line Color Down", "", core.rgb(0, 255, 0))
	indicator.parameters:addColor("color2", "Line Color Up", "", core.rgb(255, 0, 0))
	indicator.parameters:addInteger("style1", "Line Style", "", core.LINE_SOLID)
	indicator.parameters:setFlag("style1", core.FLAG_LEVEL_STYLE)
	indicator.parameters:addInteger("width1", "Line Width", "", 3, 1, 5)

	indicator.parameters:addColor("color3", "Signal Line Color", "", core.rgb(0, 0, 255))
	indicator.parameters:addInteger("style2", "Line Style", "", core.LINE_SOLID)
	indicator.parameters:setFlag("style2", core.FLAG_LEVEL_STYLE)
	indicator.parameters:addInteger("width2", "Line Width", "", 3, 1, 5)
    indicator.parameters:addColor("UP_color", "Color of Uptrend", "", core.rgb(255, 0, 0));
    indicator.parameters:addColor("DN_color", "Color of Downtend", "", core.rgb(0, 255, 0));

	indicator.parameters:addColor("UP", "Up Histogram in Up Trend", "The color of Up Histogram.", core.rgb(0, 255, 0));
	indicator.parameters:addColor("UPDOWN", "Down Histogram in Up Trend", "The color of Up Histogram.", core.rgb(0, 200, 0));
	indicator.parameters:addColor("DOWNUP", "Up Histogram in Down Trend", "The color of Down Histogram.", core.rgb(255, 0, 0));
    indicator.parameters:addColor("DOWN", "Down Histogram in Down Trend", "The color of Down Histogram.", core.rgb(200, 0, 0));
    
    indi_alerts:AddParameters(indicator.parameters);
    for i,alert in ipairs(alerts) do
        indi_alerts:AddAlert(alert.Name);
    end
end

function FindBarStream()
    for i = 0, core.host.Window.Panes:getCount() - 1 do
        local pane = core.host.Window.Panes:get(i);
        for ii = 0, pane.Data:getStreamCount() - 1 do
            local stream = pane.Data:getStream(ii);
            if stream:isBar() then
                return stream;
            end     
        end
    end
    return nil;
end

function Prepare(nameOnly)
	length = instance.parameters.length
	price_smoothing = instance.parameters.price_smoothing
	signal_smoothing = instance.parameters.signal_smoothing

	local name = profile:id() .. "(" .. instance.source:name() .. ", " .. length .. ", " .. signal_smoothing .. ")"
	instance:name(name)

	if (nameOnly) then
		return
	end

    DN_color = instance.parameters.DN_color;
    UP_color = instance.parameters.UP_color;
    UP = instance.parameters.UP;
    UPDOWN = instance.parameters.UPDOWN;
    DOWNUP = instance.parameters.DOWNUP;
    DOWN = instance.parameters.DOWN;
    indi_source = instance.source;
    
	source = FindBarStream();

	if price_smoothing > 1 then
		EMA1 = core.indicators:create("EMA", source.close, price_smoothing)
		EMA2 = core.indicators:create("EMA", source.volume, price_smoothing)

		MVA = core.indicators:create("MVA", EMA2.DATA, length)
		first = MVA.DATA:first() 
	else
		MVA = core.indicators:create("MVA", source.volume, length)
		first = MVA.DATA:first()
	end

	vpc = instance:addStream("vpc", core.Line, "vpc", "vpc", instance.parameters.color1, first)
	vpc:setWidth(instance.parameters.width1)
	vpc:setStyle(instance.parameters.style1)

	if signal_smoothing > 1 then
		EMA3 = core.indicators:create("EMA", vpc, signal_smoothing)
		signal = instance:addStream("signal", core.Line, "signal", "signal", instance.parameters.color3, first)
		signal:setWidth(instance.parameters.width2)
		signal:setStyle(instance.parameters.style2)

		signal:setPrecision(math.max(2, instance.source:getPrecision()))
        vpc:setPrecision(math.max(2, instance.source:getPrecision()))
        hist = instance:addStream("hist", core.Bar, "HIST", "HIST", UP, first, 0)
	end
    div = CreateDivergenceDetector(vpc, indi_source, indi_source, instance.parameters.UP_color, instance.parameters.DN_color, true);
    instance:ownerDrawn(true);
    
    indi_alerts:Prepare();
    indi_alerts.source = instance.source;
    instance:drawOnMainChart(true);
end

function Update(period, mode)
	if price_smoothing > 1 then
		EMA1:update(mode)
		EMA2:update(mode)
		MVA:update(mode)

		if period < MVA.DATA:first() or period < length then
			return
        end

		vpc[period] = (EMA1.DATA[period] - EMA1.DATA[period - length + 1]) * MVA.DATA[period]
	else
		MVA:update(mode)

		if period < MVA.DATA:first() then
			return
		end

		vpc[period] = (source.close[period] - source.close[period - length + 1]) * MVA.DATA[period]
	end

	if signal_smoothing > 1 then
		EMA3:update(mode)

		if period < EMA3.DATA:first() then
			return
		end

		signal[period] = EMA3.DATA[period]

		if vpc[period] > signal[period] then
			vpc:setColor(period, instance.parameters.color1)
		else
			vpc:setColor(period, instance.parameters.color2)
        end
        hist[period] = vpc[period] - signal[period];
        if hist[period] > 0 then
            if hist[period] > hist[period - 1] then
                hist:setColor(period, UP);
            else
                hist:setColor(period, UPDOWN);
            end
        else
            if hist[period] < hist[period - 1] then
                hist:setColor(period, DOWN);
            else
                hist:setColor(period, DOWNUP);
            end
        end
	end
    div:Update(period, mode);
    for _, alert in ipairs(indi_alerts.Alerts) do Activate(alert, period, period ~= source:size() - 1); end
end

function Draw(stage, context) 
    indi_alerts:Draw(stage, context, source);
    div:Draw(stage, context);
end

function CreateDivergenceDetector(indi, high, low, up_color, down_color, double_peaks)
    local controller = {};
    controller.indi = indi;
    controller.high = high;
    controller.low = low;
    controller.lines = {};
    controller.double_peaks = double_peaks;
    controller.init = false;
    controller.init2 = false;
    controller.up_color = up_color;
    controller.down_color = down_color;
    controller.UP_PEN = 1;
    controller.DN_PEN = 2;
    function controller:Update(period, mode)
        if mode == core.UpdateAll then
            self.lines = {};
        end
        if period >= 2 then
            self:processBullish(period - 2);
            self:processBearish(period - 2);
        end
    end
    function controller:Draw(stage, context)
        if stage == 102 then
            if not self.init then
                context:createPen(self.UP_PEN, context.SOLID, 1, self.up_color);
                context:createPen(self.DN_PEN, context.SOLID, 1, self.down_color);
                self.init = true;
            end
            for _, line in ipairs(self.lines) do
                local x1 = context:positionOfDate(line.Date1);
                local x2 = context:positionOfDate(line.Date2);
                local visible, y1 = context:pointOfPrice(line.Price1);
                local visible, y2 = context:pointOfPrice(line.Price2);
                context:drawLine(line.IsDown and self.DN_PEN or self.UP_PEN, x1, y1, x2, y2);
            end
        elseif stage == 2 then
            if not self.init2 then
                context:createPen(self.UP_PEN, context.SOLID, 1, self.up_color);
                context:createPen(self.DN_PEN, context.SOLID, 1, self.down_color);
                self.init2 = true;
            end
            for _, line in ipairs(self.lines) do
                local x1 = context:positionOfDate(line.Date1);
                local x2 = context:positionOfDate(line.Date2);
                local visible, y1 = context:pointOfPrice(line.IndiVal1);
                local visible, y2 = context:pointOfPrice(line.IndiVal2);
                context:drawLine(line.IsDown and self.DN_PEN or self.UP_PEN, x1, y1, x2, y2);
            end
        end
    end
    function controller:processBullish(period)
        if self:isTrough(period, self.indi) then
            local curr = period;
            local prev = self:prevTrough(period);
            if prev == nil then
                return;
            end
            if double_peaks and (not self:isTrough(curr, self.low) or not self:isTrough(prev, self.low)) then
                return;
            end
            if self.indi[curr] > self.indi[prev] and self.low[curr] < self.low[prev] then
                if self.DN ~= nil then
                    self.DN:set(curr, self.indi[curr], "\225", "Classic bullish");
                end
                local line = {};
                line.Date1 = self.indi:date(prev);
                line.Date2 = self.indi:date(curr);
                line.IndiVal1 = self.indi[prev];
                line.IndiVal2 = self.indi[curr];
                line.Price1 = self.low[prev];
                line.Price2 = self.low[curr]
                line.IsDown = true;
                self.lines[#self.lines + 1] = line;
            elseif self.indi[curr] < self.indi[prev] and self.low[curr] > self.low[prev] then
                if self.DN ~= nil then
                    self.DN:set(curr, self.indi[curr], "\225", "Reversal bullish");
                end
                local line = {};
                line.Date1 = self.indi:date(prev);
                line.Date2 = self.indi:date(curr);
                line.IndiVal1 = self.indi[prev];
                line.IndiVal2 = self.indi[curr];
                line.Price1 = self.low[prev];
                line.Price2 = self.low[curr]
                line.IsDown = true;
                self.lines[#self.lines + 1] = line;
            end
        end
    end
    function controller:isTrough(period, src)
        if src[period] < src[period - 1] and src[period] < src[period + 1] then
            for i = period - 1, first, -1 do
                if src[i] > src[period] then
                    return true;
                elseif src[period] > src[i] then
                    return false;
                end
            end
        end
        return false;
    end
    function controller:prevTrough(period)
        for i = period - 5, first, -1 do
            if self.indi[i] <= self.indi[i - 1] 
                and self.indi[i] < self.indi[i - 2] 
                and self.indi[i] <= self.indi[i + 1] 
                and self.indi[i] < self.indi[i + 2] 
            then
                return i;
            end
        end
        return nil;
    end
    function controller:processBearish(period)
        if self:isPeak(period, self.indi) then
            local curr = period;
            local prev = self:prevPeak(period);
            if prev == nil then
                return;
            end
            if double_peaks and (not self:isPeak(curr, self.low) or not self:isPeak(prev, self.low)) then
                return;
            end
            if self.indi[curr] < self.indi[prev] and self.high[curr] > self.high[prev] then
                if self.UP ~= nil then
                    self.UP:set(curr, self.indi[curr], "\226", "Classic bearish");
                end
                local line = {};
                line.Date1 = self.indi:date(prev);
                line.Date2 = self.indi:date(curr);
                line.IndiVal1 = self.indi[prev];
                line.IndiVal2 = self.indi[curr];
                line.Price1 = self.high[prev];
                line.Price2 = self.high[curr];
                line.IsDown = false;
                self.lines[#self.lines + 1] = line;
            elseif self.indi[curr] > self.indi[prev] and self.high[curr] < self.high[prev] then
                if self.UP ~= nil then
                    self.UP:set(curr, self.indi[curr], "\226", "Reversal bearish");
                end
                local line = {};
                line.Date1 = self.indi:date(prev);
                line.Date2 = self.indi:date(curr);
                line.IndiVal1 = self.indi[prev];
                line.IndiVal2 = self.indi[curr];
                line.Price1 = self.high[prev];
                line.Price2 = self.high[curr];
                line.IsDown = false;
                self.lines[#self.lines + 1] = line;
            end
        end
    end
    function controller:isPeak(period, src)
        if src[period] > src[period - 1] and src[period] > src[period + 1] then
            for i = period - 1, first, -1 do
                if src[i] < src[period] then
                    return true;
                elseif src[period] < src[i] then
                    return false;
                end
            end
        end
        return false;
    end
    function controller:prevPeak(period)
        for i = period - 5, first, -1 do
            if self.indi[i] >= self.indi[i - 1] 
                and self.indi[i] > self.indi[i - 2] 
                and self.indi[i] >= self.indi[i + 1] 
                and self.indi[i] > self.indi[i + 2] 
            then
                return i;
            end
        end
        return nil;
    end

    return controller;
end

function Activate(alert, period, historical_period)
    if indi_alerts.Live ~= "Live" then period = period - 1; end
    alert.Alert[period] = 0;
    if not alert.ON then
        if indi_alerts.FIRST then indi_alerts.FIRST = false; end
        return;
    end
    if alert.UpCondition(period) and (not alert.OnChange or not alert.UpCondition(period - 1)) then
        alert:UpAlert(source, period, source.high[period], historical_period);
    elseif alert.DownCondition(period) and (not alert.OnChange or not alert.DownCondition(period - 1)) then
        alert:DownAlert(source, period, source.low[period], historical_period);
    end

    if indi_alerts.FIRST then indi_alerts.FIRST = false; end
end

function AsyncOperationFinished(cookie, success, message, message1, message2)
    indi_alerts:AsyncOperationFinished(cookie, success, message, message1, message2)
end

indi_alerts.last_id = 0;
indi_alerts.FIRST = true;
indi_alerts._alerts = {};
indi_alerts._advanced_alert_timer = nil;
function indi_alerts:AddParameters(parameters)
    indicator.parameters:addGroup("Alert Mode");  
    indicator.parameters:addString("Live", "End of Turn / Live", "", "Live");
    indicator.parameters:addStringAlternative("Live", "End of Turn", "", "End of Turn");
    indicator.parameters:addStringAlternative("Live", "Live", "", "Live");
    indicator.parameters:addBoolean("strategy_output", "Output for strategies", "Used by the strategies", false);

    indicator.parameters:addInteger("ToTime", "Convert the date to", "", 6)
    indicator.parameters:addIntegerAlternative("ToTime", "EST", "", 1)
    indicator.parameters:addIntegerAlternative("ToTime", "UTC", "", 2)
    indicator.parameters:addIntegerAlternative("ToTime", "Local", "", 3)
    indicator.parameters:addIntegerAlternative("ToTime", "Server", "", 4)
    indicator.parameters:addIntegerAlternative("ToTime", "Financial", "", 5)
    indicator.parameters:addIntegerAlternative("ToTime", "Display", "", 6)
    
    indicator.parameters:addGroup("Alert Style");
    indicator.parameters:addInteger("Size", "Label Size", "", 10, 1 , 100);
    
    indicator.parameters:addGroup("Alerts");
    indicator.parameters:addBoolean("Show", "Show Dialog box Alert", "", false);
    indicator.parameters:addBoolean("ShowAlert", "Show Alert", "", false);
    
    indicator.parameters:addGroup("Alerts Sound");
    indicator.parameters:addBoolean("PlaySound", "Play Sound", "", false);    
    indicator.parameters:addBoolean("RecurrentSound", "Recurrent Sound", "", false);
    
    indicator.parameters:addGroup("Alerts Email");
    indicator.parameters:addBoolean("SendEmail", "Send Email", "", false);
    indicator.parameters:addString("Email", "Email", "", "");
    indicator.parameters:setFlag("Email", core.FLAG_EMAIL);

    indicator.parameters:addGroup("External Alerts");
    indicator.parameters:addBoolean("use_advanced_alert", "Send Advanced Alert", "Telegram/Discord/other platform (like MT4)", false)
	indicator.parameters:addString("advanced_alert_key", "Advanced Alert Key",
		"You can get a key via @profit_robots_bot Telegram Bot. Visit ProfitRobots.com for Discord/other platform keys", "")
end

function indi_alerts:AsyncOperationFinished(cookie, success, message, message1, message2) if cookie == self._advanced_alert_timer and #self._alerts > 0 then if self._advanced_alert_key == nil then return; end local data = self:ArrayToJSON(self._alerts); self._alerts = {}; local req = http_lua.createRequest(); local query = string.format('{"Key":"%s","StrategyName":"%s","Platform":"FXTS2","Notifications":%s}', self._advanced_alert_key, string.gsub(self.StrategyName or "", '"', '\\"'), data); req:setRequestHeader("Content-Type", "application/json"); req:setRequestHeader("Content-Length", tostring(string.len(query))); req:start("http://profitrobots.com/api/v1/notification", "POST", query); end end
function indi_alerts:ToJSON(item)
    local json = {};
    function json:AddStr(name, value) local separator = ""; if self.str ~= nil then separator = ","; else self.str = ""; end self.str = self.str .. string.format("%s\"%s\":\"%s\"", separator, tostring(name), tostring(value)); end
    function json:AddNumber(name, value) local separator = ""; if self.str ~= nil then separator = ","; else self.str = ""; end self.str = self.str .. string.format("%s\"%s\":%f", separator, tostring(name), value or 0); end
    function json:AddBool(name, value) local separator = ""; if self.str ~= nil then separator = ","; else self.str = ""; end self.str = self.str .. string.format("%s\"%s\":%s", separator, tostring(name), value and "true" or "false"); end
    function json:ToString() return "{" .. (self.str or "") .. "}"; end
    local first = true; for idx,t in pairs(item) do  local stype = type(t) if stype == "number" then json:AddNumber(idx, t); elseif stype == "string" then json:AddStr(idx, t); elseif stype == "boolean" then json:AddBool(idx, t); elseif stype == "function" or stype == "table" then else core.host:trace(tostring(idx) .. " " .. tostring(stype)); end end
    return json:ToString();
end
function indi_alerts:ArrayToJSON(arr) local str = "["; for i, t in ipairs(self._alerts) do local json = self:ToJSON(t); if str == "[" then str = str .. json; else str = str .. "," .. json; end end return str .. "]"; end
function indi_alerts:AddAlert(label)
    self.last_id = self.last_id + 1;
    indicator.parameters:addGroup(label .. " Alert");

    indicator.parameters:addBoolean("ON" .. self.last_id , "Show " .. label .." Alert" , "", true);

    indicator.parameters:addString("drawing_mode" .. self.last_id, "Drawing mode", "", "arrows");
    indicator.parameters:addStringAlternative("drawing_mode" .. self.last_id, "Arrows", "", "arrows");
    indicator.parameters:addStringAlternative("drawing_mode" .. self.last_id, "Vertical lines", "", "vlines");

    indicator.parameters:addFile("Up" .. self.last_id, label .. " Cross Over Sound", "", "");
    indicator.parameters:setFlag("Up" .. self.last_id, core.FLAG_SOUND);
    indicator.parameters:addInteger("UpSymbol" .. self.last_id, "Up Symbol", "", 217);
    indicator.parameters:addColor("UpColor" .. self.last_id, "Up Color", "", core.rgb(0, 255, 0));
    
    indicator.parameters:addFile("Down" .. self.last_id, label .. " Cross Under Sound", "", "");
    indicator.parameters:setFlag("Down" .. self.last_id, core.FLAG_SOUND);
    indicator.parameters:addInteger("DownSymbol" .. self.last_id, "Down Symbol", "", 218);
    indicator.parameters:addColor("DownColor" .. self.last_id, "Down Color", "", core.rgb(255, 0, 0));

    indicator.parameters:addString("Label" .. self.last_id, "Label", "", label);
end

function indi_alerts:AddSingleAlert(Label)
    self.last_id = self.last_id + 1;
    indicator.parameters:addGroup(Label .. " Alert");

    indicator.parameters:addBoolean("ON" .. self.last_id , "Show " .. Label .." Alert" , "", true);

    indicator.parameters:addFile("Up" .. self.last_id, Label .. " Sound", "", "");
    indicator.parameters:setFlag("Up" .. self.last_id, core.FLAG_SOUND);
    indicator.parameters:addInteger("UpSymbol" .. self.last_id, "Symbol", "", 217);
    indicator.parameters:addColor("UpColor" .. self.last_id, "Color", "", core.rgb(0, 255, 0));
    
    indicator.parameters:addString("Label" .. self.last_id, "Label", "", Label);
end

function indi_alerts:DrawAlert(context, alert, period)
    if not alert.Alert:hasData(period) then
        return;
    end

    if alert.Alert[period] == 1 then
        local x = context:positionOfBar(period);
        if alert.DrawingMode == "arrows" then
            visible, y = context:pointOfPrice(alert.AlertLevel[period]);
            width, height = context:measureText(self._stages[alert.Stage].FONT_ID, alert.UpSymbol, 0);
            local x1 = x - width / 2;
            local x2 = x + width / 2;
            local y1, y2;
            if self.inverted_arrows then
                y1 = y;
                y2 = y + height;
            else
                y1 = y - height;
                y2 = y;
            end
			context:drawText(self._stages[alert.Stage].FONT_ID, alert.UpSymbol, alert.UpColor, -1, x1, y1, x2, y2, 0);
        else
            context:drawLine(alert.UpLinePen, x, context:top(), x, context:bottom());
        end
	elseif alert.Alert[period] == -1 then
        local x = context:positionOfBar(period);
        if alert.DrawingMode == "arrows" then
            visible, y = context:pointOfPrice(alert.AlertLevel[period]);
            width, height = context:measureText(self._stages[alert.Stage].FONT_ID, alert.DownSymbol, 0);
            local x1 = x - width / 2;
            local x2 = x + width / 2;
            local y1, y2;
            if self.inverted_arrows then
                y1 = y - height;
                y2 = y;
            else
                y1 = y;
                y2 = y + height;
            end
            context:drawText(self._stages[alert.Stage].FONT_ID, alert.DownSymbol, alert.DownColor, -1, x1, y1, x2, y2, 0);
        else
            context:drawLine(alert.DownLinePen, x, context:top(), x, context:bottom());
        end
    end
end
indi_alerts.NextId = 3;
indi_alerts._stages = {};
function indi_alerts:Draw(stage, context)
    if self._stages[stage] == nil then
        self._stages[stage] = {};
        self._stages[stage].createFont = false;
        for _, level in ipairs(self.Alerts) do
            if level.Stage == stage then
                if level.DrawingMode == "vlines" then
                    level.UpLinePen = self.NextId;
                    self.NextId = self.NextId + 1;
                    level.DownLinePen = self.NextId;
                    self.NextId = self.NextId + 1;
                    context:createPen(level.UpLinePen, context.SOLID, 1, level.UpColor);
                    context:createPen(level.DownLinePen, context.SOLID, 1, level.DownColor);
                else
                    self._stages[stage].createFont = true;
                end
            end
        end
        if self._stages[stage].createFont and self._stages[stage].FONT_ID == nil then
            self._stages[stage].FONT_ID = self.NextId;
			self.NextId = self.NextId + 1;
            context:createFont(self._stages[stage].FONT_ID, "Wingdings", context:pointsToPixels(self.Size), context:pointsToPixels(self.Size), 0);
        end
    end
    for period = math.max(context:firstBar(), self.source:first()), math.min(context:lastBar(), self.source:size()-1), 1 do
        for _, level in ipairs(self.Alerts) do
            if level.Stage == stage then
                self:DrawAlert(context, level, period);
            end
        end
    end
end
indi_alerts.Alerts = {};
function indi_alerts:GetTimezone()
    local tz = instance.parameters.ToTime;
    if tz == 1 then
        return core.TZ_EST
    elseif tz == 2 then
        return core.TZ_UTC
    elseif tz == 3 then
        return core.TZ_LOCAL
    elseif tz == 4 then
        return core.TZ_SERVER
    elseif tz == 5 then
        return core.TZ_FINANCIAL
    elseif tz == 6 then
        return core.TZ_TS
    end
end
function indi_alerts:Prepare()
    self.Show = instance.parameters.Show;
    self.Live = instance.parameters.Live;
    self.ShowAlert = instance.parameters.ShowAlert;
    self.ToTime = self:GetTimezone();
    
    self.Size = instance.parameters.Size;
    self.SendEmail = instance.parameters.SendEmail;

    self.PlaySound = instance.parameters.PlaySound;
    local i;
    for i = 1, 100 do 
        local on = instance.parameters:getBoolean("ON" .. i);
        if on == nil then
            break;
        end 
        local alert = {};
        alert.id = i;
        alert.UpCondition = alerts[i].UpCondition;
        alert.FormatMessage = alerts[i].FormatMessage;
        alert.DownCondition = alerts[i].DownCondition;
        alert.OnChange = alerts[i].OnChange;
        alert.Stage = alerts[i].Stage;
        alert.Label = instance.parameters:getString("Label" .. i);
        alert.ON = on;
        alert.DrawingMode = instance.parameters:getString("drawing_mode" .. i);
        alert.UpSymbol = string.char(instance.parameters:getInteger("UpSymbol" .. i));
        local down_symbol = instance.parameters:getInteger("DownSymbol" .. i);
        if down_symbol ~= nil then
            alert.DownSymbol = string.char(down_symbol);
        end
        alert.UpColor = instance.parameters:getColor("UpColor" .. i);
        alert.DownColor = instance.parameters:getColor("DownColor" .. i);
        alert.Up = self.PlaySound and instance.parameters:getString("Up" .. i) or nil;
        alert.Down = self.PlaySound and instance.parameters:getString("Down" .. i) or nil;
        if alert.DownSymbol == nil then
            alert.DownSymbol = alert.UpSymbol;
            alert.DownColor = alert.UpColor;
            alert.Down = alert.Up;
        end
        assert(not(self.PlaySound) or (self.PlaySound and alert.Up ~= "") or (self.PlaySound and alert.Up ~= ""), "Sound file must be chosen"); 
        assert(not(self.PlaySound) or (self.PlaySound and alert.Down ~= "") or (self.PlaySound and alert.Down ~= ""), "Sound file must be chosen");
        alert.U = nil;
        alert.D = nil;
        if instance.parameters.strategy_output then
            alert.Alert = instance:addStream("strat_signal_" .. i, core.Dot, "strat_signal_" .. i, "Strategy signal #" .. i, core.rgb(0, 0, 0), 0, 0);
        else
            alert.Alert = instance:addInternalStream(0, 0);
        end
        alert.AlertLevel = instance:addInternalStream(0, 0);
        function alert:DownAlert(source, period, level, historical_period)
            local text = self.FormatMessage(source, period, level, self.Label, false);
            shift = indi_alerts.Live ~= "Live" and 1 or 0;
            self.Alert[period] = -1;
            self.AlertLevel[period] = level;
            self.U = nil;
            if self.D ~= source:date(period) and period == source:size() - 1 - shift and not indi_alerts.FIRST then
                self.D = source:date(period);
                if not historical_period then
                    indi_alerts:SoundAlert(self.Down);
                    indi_alerts:EmailAlert(self.Label, text, period);
                    indi_alerts:SendAlert(self.Label, text, period);
                    if indi_alerts.Show then
                        indi_alerts:Pop(self.Label, text);
                    end
                end
            end
        end
        function alert:UpAlert(source, period, level, historical_period)
            local text = self.FormatMessage(source, period, level, self.Label, true);
            shift = indi_alerts.Live ~= "Live" and 1 or 0;
            self.Alert[period] = 1;
            self.AlertLevel[period] = level;
            self.D = nil;
            if self.U ~= source:date(period) and period == source:size() - 1 - shift and not indi_alerts.FIRST then
                self.U = source:date(period);
                if not historical_period then
                    indi_alerts:SoundAlert(self.Up);
                    indi_alerts:EmailAlert(self.Label, text, period);
                    indi_alerts:SendAlert(self.Label, text, period);
                    if indi_alerts.Show then
                        indi_alerts:Pop(self.Label, text);
                    end
                end
            end
        end
        function alert:GetLast(period)
            for i = period, 0, -1 do
                if self.Alert:hasData(i) and self.Alert[i] ~= 0 then
                    return self.Alert[i], i, self.AlertLevel[i];
                end
            end
        end
        self.Alerts[#self.Alerts + 1] = alert;
    end

    self.Email = self.SendEmail and instance.parameters.Email or nil;
    assert(not(self.SendEmail) or (self.SendEmail and self.Email ~= ""), "E-mail address must be specified");
    self.RecurrentSound = instance.parameters.RecurrentSound;

    if instance.parameters.advanced_alert_key ~= "" and instance.parameters.use_advanced_alert then
        self._advanced_alert_key = instance.parameters.advanced_alert_key;
        require("http_lua");
        self._advanced_alert_timer = 1234;
        core.host:execute("setTimer", self._advanced_alert_timer, 1);
    end
end

function indi_alerts:Pop(label, note)
    core.host:execute("prompt", 1, label, self.source:instrument() .. " " .. label .. " : " .. note);
end

function indi_alerts:SoundAlert(Sound)
    if not self.PlaySound then
        return;
    end
    terminal:alertSound(Sound, self.RecurrentSound);
end

function indi_alerts:EmailAlert(label, Subject, period)
    if not self.SendEmail then
        return
    end

    local now = self.source:date(period);
    now = core.host:execute("convertTime", core.TZ_EST, self.ToTime, now);
    local DATA = core.dateToTable(now)
    local delim = "\013\010";  
    local Note = profile:id().. delim.. " Label : " ..label  .. delim .. " Alert : " .. Subject;   
    local Symbol = "Instrument : " .. self.source:instrument() ;
    local Time =  " Date : " .. DATA.month.." / ".. DATA.day .." Time:  ".. DATA.hour  .." / ".. DATA.min .." / ".. DATA.sec; 
    local TF = "Time Frame : " .. source:barSize()
    local text = Note  .. delim ..  Symbol .. delim .. TF .. delim .. Time;
    terminal:alertEmail(self.Email, profile:id(), text);
end

function indi_alerts:SendAlert(label, Subject, period)
    if not self.ShowAlert then
        return;
    end
    
    local now = self.source:date(period);
    now = core.host:execute("convertTime", core.TZ_EST, self.ToTime, now);
    local DATA = core.dateToTable(now)
    local delim = "\013\010";  
    local Note = profile:id().. delim.. " Label : " ..label  .. delim .. " Alert : " .. Subject;
    local Symbol= "Instrument : " .. self.source:instrument() ;
    local Time =  " Date : " .. DATA.month.." / ".. DATA.day .." Time:  ".. DATA.hour  .." / ".. DATA.min .." / ".. DATA.sec;  
    local TF = "Time Frame : " .. source:barSize()
    local text = Note  .. delim ..  Symbol .. delim .. TF .. delim .. Time;
    terminal:alertMessage(self.source:instrument(), self.source[NOW], text, self.source:date(NOW));
end

function indi_alerts:AlertTelegram(message, instrument, timeframe) local alert = {}; alert.Text = message or ""; alert.Instrument = instrument or ""; alert.TimeFrame = timeframe or ""; self._alerts[#self._alerts + 1] = alert; end