Limit Order Execution

OpenAlgo Limit Order Execution Module

The OpenAlgo Limit Order Execution Module is an AmiBroker AFL-based trading tool designed to automate limit order placement with intelligent price improvement and retry logic. It connects to the OpenAlgo API to fetch real-time bid/ask quotes and execute limit orders at calculated prices based on five configurable modes: Mid-Price, Best Bid, Best Ask, Bid Offset, and Ask Offset. The module features a visual GFX dashboard that displays live market data including bid, ask, LTP, mid-price, and spread, along with complete order status tracking showing the current state, order ID, execution price, and retry count.

The execution workflow follows a state machine architecture that places a limit order at the calculated price, monitors order status, and automatically modifies the order with fresh quotes if it remains unfilled. This modify-and-retry loop continues up to a configurable number of attempts (default: 3), after which the pending order is automatically canceled. The module supports configurable tick sizes for proper price rounding across different instruments (stocks, futures, commodities), making it suitable for exchanges like NSE, NFO, MCX, and others. Users can trigger BUY or SELL orders via parameter buttons, manually cancel active orders, or reset the module state as needed.

Amibroker Execution Module

_SECTION_BEGIN("OpenAlgo Limit Order Execution Module");

RequestTimedRefresh(5, False);

/* ******************************************************************** */
/* USER PARAMETERS */
/* ******************************************************************** */
apiKey = ParamStr("API Key", "your_api_key_here");
symbolNm = ParamStr("Symbol", "CRUDEOIL18DEC25FUT");
exchangeNm = ParamList("Exchange", "MCX|NSE|NFO|CDS|BSE|BFO|BCD");
strategyNm = ParamStr("Strategy Name", "LimitExec");
quantity = Param("Quantity", 1, 1, 10000, 1);
prdType = ParamList("Product", "MIS|CNC|NRML");

/* Execution Settings */
priceMode = ParamList("Price Mode", "MidPrice|BestBid|BestAsk|BidOffset|AskOffset");
tickOffset = Param("Tick Offset", 1, 0, 10, 1);
tickSizeStr = ParamList("Tick Size", "1|0.01|0.05|0.1|0.2|0.25|0.5|5|10|25");
tickSize = StrToNum(tickSizeStr);
maxRetries = Param("Max Retries", 3, 1, 10, 1);
retryDelaySec = Param("Retry Delay (Sec)", 1, 1, 10, 1);

/* Trigger Buttons */
triggerBuy = ParamTrigger("Place BUY Limit", "BUY NOW");
triggerSell = ParamTrigger("Place SELL Limit", "SELL NOW");
triggerCancel = ParamTrigger("Cancel Order", "CANCEL");
triggerReset = ParamTrigger("Reset Module", "RESET");

/* GFX Settings */
cellHeight = Param("Cell Height", 30, 20, 50, 1);
cellWidth = Param("Cell Width", 130, 80, 200, 1);
startX = Param("Start X", 50, 0, 1200, 1);
startY = Param("Start Y", 80, 0, 1200, 1);

/* Colors */
headerBgColor = ParamColor("Header BG", colorDarkBlue);
headerTextColor = ParamColor("Header Text", colorWhite);
bidBgColor = ParamColor("Bid BG", colorDarkGreen);
askBgColor = ParamColor("Ask BG", colorDarkRed);
infoBgColor = ParamColor("Info BG", colorGrey40);
infoTextColor = ParamColor("Info Text", colorWhite);

/* State Constants */
STATE_IDLE = 0;
STATE_PLACING = 1;
STATE_MONITORING = 2;
STATE_MODIFYING = 3;
STATE_CANCELING = 4;
STATE_FINAL_CHECK = 5;
STATE_COMPLETE = 6;
STATE_CANCELED = 7;
STATE_REJECTED = 8;

/* ******************************************************************** */
/* CHECK API KEY VALIDITY */
/* ******************************************************************** */
apiKeyValid = True;
if(apiKey == "your_api_key_here" OR StrLen(apiKey) < 10)
{
    apiKeyValid = False;
}

/* ******************************************************************** */
/* ROUND PRICE TO NEAREST TICK SIZE */
/* ******************************************************************** */
function RoundToTick(price, tick)
{
    roundedPrice = round(price / tick) * tick;
    return roundedPrice;
}

/* ******************************************************************** */
/* JSON EXTRACTION FUNCTION */
/* ******************************************************************** */
function ExtractJsonValue(jsonStr, keyName, isNested)
{
    result = "";
    jsonData = jsonStr;

    if(isNested)
    {
        dataStart = StrFind(jsonStr, "\"data\":{");
        if(dataStart > 0) dataStart = dataStart - 1;
        
        if(dataStart >= 0)
        {
            valueStart = dataStart + 7;
            valueEnd = valueStart;
            braceCount = 1;
            strLenJson = StrLen(jsonStr);

            while(valueEnd < strLenJson)
            {
                currChar = StrMid(jsonStr, valueEnd, 1);
                if(currChar == "{") braceCount++;
                if(currChar == "}") braceCount--;
                if(braceCount == 0) break;
                valueEnd++;
            }
            
            jsonData = StrMid(jsonStr, valueStart, valueEnd - valueStart);
        }
    }
    
    keyPos = StrFind(jsonData, "\"" + keyName + "\":");
    if(keyPos > 0) keyPos = keyPos - 1;
    
    if(keyPos > -1)
    {
        valueStart = keyPos + StrLen(keyName) + 3;
        while(StrMid(jsonData, valueStart, 1) == " ") valueStart++;
        
        firstValChar = StrMid(jsonData, valueStart, 1);
        isQuoted = (firstValChar == "\"");
        
        strLenData = StrLen(jsonData);
        valueEnd = valueStart;
        
        if(isQuoted)
        {
            valueStart++;
            valueEnd = valueStart;
            while(valueEnd < strLenData)
            {
                currChar = StrMid(jsonData, valueEnd, 1);
                if(currChar == "\"") break;
                valueEnd++;
            }
            result = StrMid(jsonData, valueStart, valueEnd - valueStart);
        }
        else
        {
            while(valueEnd < strLenData)
            {
                currChar = StrMid(jsonData, valueEnd, 1);
                if(currChar == "," OR currChar == "}") break;
                valueEnd++;
            }
            result = StrMid(jsonData, valueStart, valueEnd - valueStart);
        }
    }
    
    return result;
}

/* ******************************************************************** */
/* GFX TABLE CELL FUNCTION */
/* ******************************************************************** */
function TableCell(text, col, row, bgColor, textColor)
{
    x1 = startX + (col - 1) * cellWidth;
    y1 = startY + (row - 1) * cellHeight;
    x2 = x1 + cellWidth;
    y2 = y1 + cellHeight;
    textX = x1 + (cellWidth / 2);
    textY = y1 + (cellHeight / 2) - 6;

    GfxSelectPen(colorBlack, 1);
    GfxSelectSolidBrush(bgColor);
    GfxRectangle(x1, y1, x2, y2);

    GfxSetBkColor(bgColor);
    GfxSetTextAlign(6);
    GfxSetTextColor(textColor);
    GfxTextOut(text, textX, textY);
    
    return 1;
}

/* ******************************************************************** */
/* WIDE TABLE CELL FUNCTION */
/* ******************************************************************** */
function TableCellWide(text, col, row, colSpan, bgColor, textColor)
{
    x1 = startX + (col - 1) * cellWidth;
    y1 = startY + (row - 1) * cellHeight;
    x2 = x1 + (cellWidth * colSpan);
    y2 = y1 + cellHeight;
    textX = x1 + ((cellWidth * colSpan) / 2);
    textY = y1 + (cellHeight / 2) - 6;

    GfxSelectPen(colorBlack, 1);
    GfxSelectSolidBrush(bgColor);
    GfxRectangle(x1, y1, x2, y2);

    GfxSetBkColor(bgColor);
    GfxSetTextAlign(6);
    GfxSetTextColor(textColor);
    GfxTextOut(text, textX, textY);
    
    return 1;
}

/* ******************************************************************** */
/* API: FETCH QUOTES */
/* ******************************************************************** */
function FetchQuotes(apiKeyLocal, sym, exch)
{
    returnValue = 0;
    urlMain = "http://127.0.0.1:5000/api/v1/quotes";
    
    postBody = "{";
    postBody += "\"apikey\":\"" + apiKeyLocal + "\",";
    postBody += "\"symbol\":\"" + sym + "\",";
    postBody += "\"exchange\":\"" + exch + "\"";
    postBody += "}";
    
    InternetSetHeaders("Content-Type: application/json\r\n");
    ih = InternetPostRequest(urlMain, postBody);
    
    if(ih)
    {
        rsp = "";
        respLine = InternetReadString(ih);
        while(respLine != "")
        {
            rsp += respLine;
            respLine = InternetReadString(ih);
        }
        InternetClose(ih);
        
        _TRACEF("Quotes Response: %s", rsp);
        
        statusVal = ExtractJsonValue(rsp, "status", False);
        if(StrFind(statusVal, "success") > 0)
        {
            bidVal = StrToNum(ExtractJsonValue(rsp, "bid", True));
            askVal = StrToNum(ExtractJsonValue(rsp, "ask", True));
            ltpVal = StrToNum(ExtractJsonValue(rsp, "ltp", True));
            
            StaticVarSet("LimitExec_Bid", bidVal);
            StaticVarSet("LimitExec_Ask", askVal);
            StaticVarSet("LimitExec_LTP", ltpVal);
            StaticVarSet("LimitExec_QuoteTime", Now(4));
            
            returnValue = 1;
        }
    }
    else
    {
        _TRACE("FetchQuotes Failed");
    }
    
    return returnValue;
}

/* ******************************************************************** */
/* API: PLACE LIMIT ORDER */
/* ******************************************************************** */
function PlaceLimitOrder(apiKeyLocal, strat, sym, exch, action, prdParam, qty, limitPrice)
{
    returnValue = 0;
    urlMain = "http://127.0.0.1:5000/api/v1/placeorder";
    
    postBody = "{";
    postBody += "\"apikey\":\"" + apiKeyLocal + "\",";
    postBody += "\"strategy\":\"" + strat + "\",";
    postBody += "\"symbol\":\"" + sym + "\",";
    postBody += "\"exchange\":\"" + exch + "\",";
    postBody += "\"action\":\"" + action + "\",";
    postBody += "\"product\":\"" + prdParam + "\",";
    postBody += "\"pricetype\":\"LIMIT\",";
    postBody += "\"quantity\":\"" + NumToStr(qty, 1.0, False) + "\",";
    postBody += "\"price\":\"" + NumToStr(limitPrice, 1.2, False) + "\",";
    postBody += "\"trigger_price\":\"0\",";
    postBody += "\"disclosed_quantity\":\"0\"";
    postBody += "}";
    
    _TRACEF("PlaceOrder Request: %s", postBody);
    
    InternetSetHeaders("Content-Type: application/json\r\n");
    ih = InternetPostRequest(urlMain, postBody);
    
    if(ih)
    {
        rsp = "";
        respLine = InternetReadString(ih);
        while(respLine != "")
        {
            rsp += respLine;
            respLine = InternetReadString(ih);
        }
        InternetClose(ih);
        
        _TRACEF("PlaceOrder Response: %s", rsp);
        
        statusVal = ExtractJsonValue(rsp, "status", False);
        if(StrFind(statusVal, "success") > 0)
        {
            orderID = ExtractJsonValue(rsp, "orderid", False);
            StaticVarSetText("LimitExec_OrderID", orderID);
            returnValue = 1;
        }
    }
    else
    {
        _TRACE("PlaceLimitOrder Failed");
    }
    
    return returnValue;
}

/* ******************************************************************** */
/* API: CHECK ORDER STATUS */
/* ******************************************************************** */
function CheckOrderStatus(apiKeyLocal, strat, orderID)
{
    returnValue = 0;
    urlMain = "http://127.0.0.1:5000/api/v1/orderstatus";
    
    postBody = "{";
    postBody += "\"apikey\":\"" + apiKeyLocal + "\",";
    postBody += "\"strategy\":\"" + strat + "\",";
    postBody += "\"orderid\":\"" + orderID + "\"";
    postBody += "}";
    
    InternetSetHeaders("Content-Type: application/json\r\n");
    ih = InternetPostRequest(urlMain, postBody);
    
    if(ih)
    {
        rsp = "";
        respLine = InternetReadString(ih);
        while(respLine != "")
        {
            rsp += respLine;
            respLine = InternetReadString(ih);
        }
        InternetClose(ih);
        
        _TRACEF("OrderStatus Response: %s", rsp);
        
        statusVal = ExtractJsonValue(rsp, "status", False);
        if(StrFind(statusVal, "success") > 0)
        {
            orderStatus = ExtractJsonValue(rsp, "order_status", True);
            avgPrice = StrToNum(ExtractJsonValue(rsp, "average_price", True));
            
            StaticVarSetText("LimitExec_OrderStatus", orderStatus);
            StaticVarSet("LimitExec_FilledPrice", avgPrice);
            
            returnValue = 1;
        }
    }
    else
    {
        _TRACE("CheckOrderStatus Failed");
    }
    
    return returnValue;
}

/* ******************************************************************** */
/* API: MODIFY ORDER */
/* ******************************************************************** */
function ModifyLimitOrder(apiKeyLocal, strat, sym, exch, action, orderID, prdParam, qty, newPrice)
{
    returnValue = 0;
    urlMain = "http://127.0.0.1:5000/api/v1/modifyorder";
    
    postBody = "{";
    postBody += "\"apikey\":\"" + apiKeyLocal + "\",";
    postBody += "\"strategy\":\"" + strat + "\",";
    postBody += "\"symbol\":\"" + sym + "\",";
    postBody += "\"exchange\":\"" + exch + "\",";
    postBody += "\"action\":\"" + action + "\",";
    postBody += "\"orderid\":\"" + orderID + "\",";
    postBody += "\"product\":\"" + prdParam + "\",";
    postBody += "\"pricetype\":\"LIMIT\",";
    postBody += "\"quantity\":\"" + NumToStr(qty, 1.0, False) + "\",";
    postBody += "\"price\":\"" + NumToStr(newPrice, 1.2, False) + "\",";
    postBody += "\"trigger_price\":\"0\",";
    postBody += "\"disclosed_quantity\":\"0\"";
    postBody += "}";
    
    _TRACEF("ModifyOrder Request: %s", postBody);
    
    InternetSetHeaders("Content-Type: application/json\r\n");
    ih = InternetPostRequest(urlMain, postBody);
    
    if(ih)
    {
        rsp = "";
        respLine = InternetReadString(ih);
        while(respLine != "")
        {
            rsp += respLine;
            respLine = InternetReadString(ih);
        }
        InternetClose(ih);
        
        _TRACEF("ModifyOrder Response: %s", rsp);
        
        statusVal = ExtractJsonValue(rsp, "status", False);
        if(StrFind(statusVal, "success") > 0)
        {
            returnValue = 1;
        }
    }
    else
    {
        _TRACE("ModifyLimitOrder Failed");
    }
    
    return returnValue;
}

/* ******************************************************************** */
/* API: CANCEL ORDER */
/* ******************************************************************** */
function CancelLimitOrder(apiKeyLocal, strat, orderID)
{
    returnValue = 0;
    urlMain = "http://127.0.0.1:5000/api/v1/cancelorder";
    
    postBody = "{";
    postBody += "\"apikey\":\"" + apiKeyLocal + "\",";
    postBody += "\"strategy\":\"" + strat + "\",";
    postBody += "\"orderid\":\"" + orderID + "\"";
    postBody += "}";
    
    _TRACEF("CancelOrder Request: %s", postBody);
    
    InternetSetHeaders("Content-Type: application/json\r\n");
    ih = InternetPostRequest(urlMain, postBody);
    
    if(ih)
    {
        rsp = "";
        respLine = InternetReadString(ih);
        while(respLine != "")
        {
            rsp += respLine;
            respLine = InternetReadString(ih);
        }
        InternetClose(ih);
        
        _TRACEF("CancelOrder Response: %s", rsp);
        
        statusVal = ExtractJsonValue(rsp, "status", False);
        if(StrFind(statusVal, "success") > 0)
        {
            returnValue = 1;
        }
    }
    else
    {
        _TRACE("CancelLimitOrder Failed");
    }
    
    return returnValue;
}

/* ******************************************************************** */
/* CALCULATE LIMIT PRICE BASED ON MODE */
/* ******************************************************************** */
function CalculateLimitPrice(action, mode, bid, ask, offsetTicks, tick)
{
    midPrice = (bid + ask) / 2;
    calcPrice = midPrice;
    
    if(mode == "MidPrice")
    {
        calcPrice = midPrice;
    }
    
    if(mode == "BestBid")
    {
        calcPrice = bid;
    }
    
    if(mode == "BestAsk")
    {
        calcPrice = ask;
    }
    
    if(mode == "BidOffset")
    {
        calcPrice = bid + (offsetTicks * tick);
    }
    
    if(mode == "AskOffset")
    {
        calcPrice = ask - (offsetTicks * tick);
    }
    
    calcPrice = round(calcPrice / tick) * tick;
    
    return calcPrice;
}

/* ******************************************************************** */
/* INITIALIZE STATIC VARIABLES */
/* ******************************************************************** */
if(IsNull(StaticVarGet("LimitExec_State")))
{
    StaticVarSet("LimitExec_State", STATE_IDLE);
    StaticVarSetText("LimitExec_OrderID", "");
    StaticVarSetText("LimitExec_Action", "");
    StaticVarSetText("LimitExec_OrderStatus", "");
    StaticVarSetText("LimitExec_Message", "Ready");
    StaticVarSet("LimitExec_RetryCount", 0);
    StaticVarSet("LimitExec_LastActionTime", 0);
    StaticVarSet("LimitExec_OrderPrice", 0);
    StaticVarSet("LimitExec_FilledPrice", 0);
    StaticVarSet("LimitExec_Bid", 0);
    StaticVarSet("LimitExec_Ask", 0);
    StaticVarSet("LimitExec_LTP", 0);
    StaticVarSet("LimitExec_MidPrice", 0);
}

/* ******************************************************************** */
/* HANDLE RESET TRIGGER */
/* ******************************************************************** */
if(triggerReset)
{
    StaticVarSet("LimitExec_State", STATE_IDLE);
    StaticVarSetText("LimitExec_OrderID", "");
    StaticVarSetText("LimitExec_Action", "");
    StaticVarSetText("LimitExec_OrderStatus", "");
    StaticVarSetText("LimitExec_Message", "Module Reset");
    StaticVarSet("LimitExec_RetryCount", 0);
    StaticVarSet("LimitExec_LastActionTime", 0);
    StaticVarSet("LimitExec_OrderPrice", 0);
    StaticVarSet("LimitExec_FilledPrice", 0);
    _TRACE("=== MODULE RESET ===");
}

/* ******************************************************************** */
/* RETRIEVE CURRENT STATE */
/* ******************************************************************** */
currentState = StaticVarGet("LimitExec_State");
currentTime = Now(4);
lastActionTime = StaticVarGet("LimitExec_LastActionTime");
retryCount = StaticVarGet("LimitExec_RetryCount");
orderID = StaticVarGetText("LimitExec_OrderID");
actionType = StaticVarGetText("LimitExec_Action");

/* ******************************************************************** */
/* MAIN LOGIC - ONLY EXECUTE IF API KEY IS VALID */
/* ******************************************************************** */
if(apiKeyValid)
{
    /* ******************************************************************** */
    /* FETCH QUOTES PERIODICALLY */
    /* ******************************************************************** */
    quoteRefreshTime = StaticVarGet("LimitExec_QuoteTime");
    if(IsNull(quoteRefreshTime)) quoteRefreshTime = 0;

    if(currentTime - quoteRefreshTime >= 2)
    {
        FetchQuotes(apiKey, symbolNm, exchangeNm);
    }

    /* Calculate Mid Price with Tick Rounding */
    bidPrice = StaticVarGet("LimitExec_Bid");
    askPrice = StaticVarGet("LimitExec_Ask");
    ltpPrice = StaticVarGet("LimitExec_LTP");
    midPriceRaw = (bidPrice + askPrice) / 2;
    midPrice = RoundToTick(midPriceRaw, tickSize);
    StaticVarSet("LimitExec_MidPrice", midPrice);

    /* ******************************************************************** */
    /* HANDLE BUY/SELL TRIGGERS */
    /* ******************************************************************** */
    if(triggerBuy AND currentState == STATE_IDLE)
    {
        StaticVarSetText("LimitExec_Action", "BUY");
        StaticVarSet("LimitExec_State", STATE_PLACING);
        StaticVarSet("LimitExec_RetryCount", 0);
        StaticVarSetText("LimitExec_Message", "Initiating BUY order...");
        _TRACE("=== BUY TRIGGERED ===");
    }

    if(triggerSell AND currentState == STATE_IDLE)
    {
        StaticVarSetText("LimitExec_Action", "SELL");
        StaticVarSet("LimitExec_State", STATE_PLACING);
        StaticVarSet("LimitExec_RetryCount", 0);
        StaticVarSetText("LimitExec_Message", "Initiating SELL order...");
        _TRACE("=== SELL TRIGGERED ===");
    }

    /* ******************************************************************** */
    /* HANDLE MANUAL CANCEL TRIGGER */
    /* ******************************************************************** */
    if(triggerCancel AND currentState != STATE_IDLE AND StrLen(orderID) > 0)
    {
        StaticVarSet("LimitExec_State", STATE_CANCELING);
        StaticVarSetText("LimitExec_Message", "Manual cancel requested...");
        _TRACE("=== MANUAL CANCEL TRIGGERED ===");
    }

    /* ******************************************************************** */
    /* STATE MACHINE PROCESSING */
    /* ******************************************************************** */
    currentState = StaticVarGet("LimitExec_State");
    actionType = StaticVarGetText("LimitExec_Action");

    /* STATE: PLACING */
    if(currentState == STATE_PLACING)
    {
        FetchQuotes(apiKey, symbolNm, exchangeNm);
        bidPrice = StaticVarGet("LimitExec_Bid");
        askPrice = StaticVarGet("LimitExec_Ask");
        
        limitPrice = CalculateLimitPrice(actionType, priceMode, bidPrice, askPrice, tickOffset, tickSize);
        StaticVarSet("LimitExec_OrderPrice", limitPrice);
        
        successPlace = PlaceLimitOrder(apiKey, strategyNm, symbolNm, exchangeNm, actionType, prdType, quantity, limitPrice);
        
        if(successPlace)
        {
            StaticVarSet("LimitExec_State", STATE_MONITORING);
            StaticVarSet("LimitExec_LastActionTime", currentTime);
            StaticVarSetText("LimitExec_Message", "Order placed. Monitoring...");
            _TRACEF("Order Placed: %s @ %.2f", StaticVarGetText("LimitExec_OrderID"), limitPrice);
        }
        else
        {
            StaticVarSet("LimitExec_State", STATE_REJECTED);
            StaticVarSetText("LimitExec_Message", "Order placement failed!");
        }
    }

    /* STATE: MONITORING */
    if(currentState == STATE_MONITORING)
    {
        if(currentTime - lastActionTime >= retryDelaySec)
        {
            orderID = StaticVarGetText("LimitExec_OrderID");
            successStatus = CheckOrderStatus(apiKey, strategyNm, orderID);
            
            if(successStatus)
            {
                orderStatus = StaticVarGetText("LimitExec_OrderStatus");
                
                if(StrFind(orderStatus, "complete") > 0)
                {
                    StaticVarSet("LimitExec_State", STATE_COMPLETE);
                    StaticVarSetText("LimitExec_Message", "Order FILLED!");
                    _TRACE("=== ORDER COMPLETE ===");
                }
                else if(StrFind(orderStatus, "rejected") > 0 OR StrFind(orderStatus, "cancelled") > 0)
                {
                    StaticVarSet("LimitExec_State", STATE_REJECTED);
                    StaticVarSetText("LimitExec_Message", "Order REJECTED/CANCELLED");
                    _TRACE("=== ORDER REJECTED ===");
                }
                else if(StrFind(orderStatus, "open") > 0 OR StrFind(orderStatus, "pending") > 0)
                {
                    retryCount = StaticVarGet("LimitExec_RetryCount");
                    
                    if(retryCount < maxRetries)
                    {
                        StaticVarSet("LimitExec_State", STATE_MODIFYING);
                        StaticVarSetText("LimitExec_Message", StrFormat("Open. Retry %g of %g...", retryCount + 1, maxRetries));
                    }
                    else
                    {
                        StaticVarSet("LimitExec_State", STATE_CANCELING);
                        StaticVarSetText("LimitExec_Message", "Max retries. Canceling...");
                        _TRACE("=== MAX RETRIES - CANCELING ===");
                    }
                }
            }
            
            StaticVarSet("LimitExec_LastActionTime", currentTime);
        }
    }

    /* STATE: MODIFYING */
    if(currentState == STATE_MODIFYING)
    {
        FetchQuotes(apiKey, symbolNm, exchangeNm);
        bidPrice = StaticVarGet("LimitExec_Bid");
        askPrice = StaticVarGet("LimitExec_Ask");
        
        actionType = StaticVarGetText("LimitExec_Action");
        newPrice = CalculateLimitPrice(actionType, priceMode, bidPrice, askPrice, tickOffset, tickSize);
        StaticVarSet("LimitExec_OrderPrice", newPrice);
        
        orderID = StaticVarGetText("LimitExec_OrderID");
        successModify = ModifyLimitOrder(apiKey, strategyNm, symbolNm, exchangeNm, actionType, orderID, prdType, quantity, newPrice);
        
        if(successModify)
        {
            retryCount = StaticVarGet("LimitExec_RetryCount");
            StaticVarSet("LimitExec_RetryCount", retryCount + 1);
            StaticVarSet("LimitExec_State", STATE_MONITORING);
            StaticVarSet("LimitExec_LastActionTime", currentTime);
            StaticVarSetText("LimitExec_Message", StrFormat("Modified @ %.2f. Monitoring...", newPrice));
            _TRACEF("Order Modified: Retry %g @ %.2f", retryCount + 1, newPrice);
        }
        else
        {
            StaticVarSet("LimitExec_State", STATE_CANCELING);
            StaticVarSetText("LimitExec_Message", "Modify failed. Canceling...");
        }
    }

    /* STATE: CANCELING */
    if(currentState == STATE_CANCELING)
    {
        orderID = StaticVarGetText("LimitExec_OrderID");
        CancelLimitOrder(apiKey, strategyNm, orderID);
        
        StaticVarSet("LimitExec_State", STATE_FINAL_CHECK);
        StaticVarSet("LimitExec_LastActionTime", currentTime);
        StaticVarSetText("LimitExec_Message", "Cancel sent. Final check...");
        _TRACE("Cancel request sent");
    }

    /* STATE: FINAL_CHECK */
    if(currentState == STATE_FINAL_CHECK)
    {
        if(currentTime - lastActionTime >= retryDelaySec)
        {
            orderID = StaticVarGetText("LimitExec_OrderID");
            successFinal = CheckOrderStatus(apiKey, strategyNm, orderID);
            
            if(successFinal)
            {
                orderStatus = StaticVarGetText("LimitExec_OrderStatus");
                
                if(StrFind(orderStatus, "complete") > 0)
                {
                    StaticVarSet("LimitExec_State", STATE_COMPLETE);
                    StaticVarSetText("LimitExec_Message", "Filled during cancel!");
                    _TRACE("=== FILLED DURING CANCEL ===");
                }
                else
                {
                    StaticVarSet("LimitExec_State", STATE_CANCELED);
                    StaticVarSetText("LimitExec_Message", "Order CANCELED");
                    _TRACE("=== ORDER CANCELED ===");
                }
            }
            else
            {
                StaticVarSet("LimitExec_State", STATE_CANCELED);
                StaticVarSetText("LimitExec_Message", "Assumed Canceled");
            }
        }
    }
}
else
{
    StaticVarSetText("LimitExec_Message", "Please configure valid API Key");
}

/* ******************************************************************** */
/* READ FINAL STATE FOR DISPLAY */
/* ******************************************************************** */
currentState = StaticVarGet("LimitExec_State");
orderID = StaticVarGetText("LimitExec_OrderID");
actionType = StaticVarGetText("LimitExec_Action");
orderStatus = StaticVarGetText("LimitExec_OrderStatus");
message = StaticVarGetText("LimitExec_Message");
retryCount = StaticVarGet("LimitExec_RetryCount");
orderPrice = StaticVarGet("LimitExec_OrderPrice");
filledPrice = StaticVarGet("LimitExec_FilledPrice");
bidPrice = StaticVarGet("LimitExec_Bid");
askPrice = StaticVarGet("LimitExec_Ask");
ltpPrice = StaticVarGet("LimitExec_LTP");
midPrice = StaticVarGet("LimitExec_MidPrice");
spreadVal = askPrice - bidPrice;

stateText = "IDLE";
if(currentState == STATE_PLACING) stateText = "PLACING";
if(currentState == STATE_MONITORING) stateText = "MONITORING";
if(currentState == STATE_MODIFYING) stateText = "MODIFYING";
if(currentState == STATE_CANCELING) stateText = "CANCELING";
if(currentState == STATE_FINAL_CHECK) stateText = "FINAL CHECK";
if(currentState == STATE_COMPLETE) stateText = "COMPLETE";
if(currentState == STATE_CANCELED) stateText = "CANCELED";
if(currentState == STATE_REJECTED) stateText = "REJECTED";

stateBgColor = infoBgColor;
if(currentState == STATE_COMPLETE) stateBgColor = colorDarkGreen;
if(currentState == STATE_CANCELED OR currentState == STATE_REJECTED) stateBgColor = colorDarkRed;
if(currentState == STATE_MONITORING OR currentState == STATE_MODIFYING) stateBgColor = colorDarkYellow;

/* ******************************************************************** */
/* RENDER GFX DASHBOARD */
/* ******************************************************************** */
GfxSetBkMode(1);
GfxSelectFont("Arial", 14, 700);
GfxSetTextColor(colorWhite);
GfxTextOut("LIMIT ORDER EXECUTION - " + symbolNm + " (" + exchangeNm + ")", startX, startY - 25);

TableCellWide("MARKET DATA", 1, 1, 4, headerBgColor, headerTextColor);

TableCell("BID", 1, 2, headerBgColor, headerTextColor);
TableCellWide("LTP", 2, 2, 2, headerBgColor, headerTextColor);
TableCell("ASK", 4, 2, headerBgColor, headerTextColor);

TableCell(StrFormat("%.2f", bidPrice), 1, 3, bidBgColor, colorWhite);
TableCellWide(StrFormat("%.2f", ltpPrice), 2, 3, 2, infoBgColor, colorYellow);
TableCell(StrFormat("%.2f", askPrice), 4, 3, askBgColor, colorWhite);

TableCell("MID", 1, 4, headerBgColor, headerTextColor);
TableCell(StrFormat("%.2f", midPrice), 2, 4, infoBgColor, infoTextColor);
TableCell("SPREAD", 3, 4, headerBgColor, headerTextColor);
TableCell(StrFormat("%.2f", spreadVal), 4, 4, infoBgColor, infoTextColor);

TableCellWide("", 1, 5, 4, colorBlack, colorWhite);

TableCellWide("ORDER STATUS", 1, 6, 4, headerBgColor, headerTextColor);

TableCell("STATE", 1, 7, headerBgColor, headerTextColor);
TableCellWide("ORDER ID", 2, 7, 3, headerBgColor, headerTextColor);

TableCell(stateText, 1, 8, stateBgColor, colorWhite);
displayOrderID = orderID;
if(StrLen(orderID) == 0) displayOrderID = "---";
TableCellWide(displayOrderID, 2, 8, 3, infoBgColor, infoTextColor);

TableCell("ACTION", 1, 9, headerBgColor, headerTextColor);
TableCell("PRICE", 2, 9, headerBgColor, headerTextColor);
TableCell("RETRY", 3, 9, headerBgColor, headerTextColor);
TableCell("FILLED", 4, 9, headerBgColor, headerTextColor);

displayAction = actionType;
if(StrLen(actionType) == 0) displayAction = "---";
actionBgColor = infoBgColor;
if(actionType == "BUY") actionBgColor = bidBgColor;
if(actionType == "SELL") actionBgColor = askBgColor;
TableCell(displayAction, 1, 10, actionBgColor, colorWhite);
TableCell(StrFormat("%.2f", orderPrice), 2, 10, infoBgColor, infoTextColor);
TableCell(StrFormat("%g / %g", retryCount, maxRetries), 3, 10, infoBgColor, infoTextColor);
filledDisplay = "---";
if(filledPrice > 0) filledDisplay = StrFormat("%.2f", filledPrice);
TableCell(filledDisplay, 4, 10, infoBgColor, colorGreen);

TableCellWide("", 1, 11, 4, colorBlack, colorWhite);

TableCellWide(message, 1, 12, 4, colorGrey50, colorYellow);

GfxSelectFont("Arial", 9, 400);
GfxSetTextColor(colorGrey50);
GfxTextOut("Mode: " + priceMode + " | Tick: " + tickSizeStr + " | Qty: " + NumToStr(quantity, 1.0) + " | Product: " + prdType, startX, startY + (13 * cellHeight));

/* API Key Warning */
if(NOT apiKeyValid)
{
    GfxSelectFont("Arial", 12, 700);
    GfxSetTextColor(colorRed);
    GfxTextOut("WARNING: Please configure a valid API Key in Parameters", startX, startY + (14 * cellHeight) + 10);
}

_SECTION_END();


_SECTION_BEGIN("Candle with X-Axis");

SetChartOptions(0, chartShowArrows | chartShowDates);

_N(Title = StrFormat("{{NAME}} - {{INTERVAL}} {{DATE}} Open %g, Hi %g, Lo %g, Close %g (%.1f%%) {{VALUES}}", O, H, L, C, SelectedValue(ROC(C, 1))));

Plot(Close, "Close", ParamColor("Color", colorDefault), styleNoTitle | ParamStyle("Style") | GetPriceStyle());

_SECTION_END();

Key Features Implemented

Feature	Description
5 Price Modes	MidPrice, BestBid, BestAsk, BidOffset, AskOffset
Auto-Retry Logic	Modifies order up to N times if still open
State Machine	9 states for robust order lifecycle management
GFX Dashboard	Real-time bid/ask/ltp, order status, retry counter
Manual Override	Cancel button works at any state
Tick Rounding	Prices rounded to configurable tick size

---

Limit Order Execution Module - Design Document

---

Overview

Purpose: Execute limit orders with automatic retry/modification logic and visual dashboard tracking

Supported Exchanges: NSE, NFO, CDS, BSE, BFO, BCD, MCX

Execution Flow:

Place Limit Order → Monitor Status → Modify if Open (max N times) → Cancel if Still Open → Final Status Check

---

State Machine Design

State	Description	Next State
IDLE	No active order, waiting for user trigger	PLACING
PLACING	Sending order to API	MONITORING / REJECTED
MONITORING	Checking order status	COMPLETE / MODIFYING / CANCELING / REJECTED
MODIFYING	Modifying order price (retry loop)	MONITORING / CANCELING
CANCELING	Canceling pending order	FINAL_CHECK
FINAL_CHECK	Last status check after cancel	COMPLETE / CANCELED
COMPLETE	Order filled	IDLE (via Reset)
CANCELED	Order canceled	IDLE (via Reset)
REJECTED	Order rejected by broker	IDLE (via Reset)

---

Parameters

Connection Settings

Parameter	Type	Description
API Key	ParamStr	OpenAlgo authentication key
Symbol	ParamStr	Trading symbol (e.g., CRUDEOIL18DEC25FUT)
Exchange	ParamList	MCX, NSE, NFO, CDS, BSE, BFO, BCD
Strategy Name	ParamStr	Strategy identifier for order tracking

Order Settings

Parameter	Type	Description
Quantity	Param	Order quantity (1-10000)
Product	ParamList	MIS, CNC, NRML

Execution Settings

Parameter	Type	Description
Price Mode	ParamList	MidPrice, BestBid, BestAsk, BidOffset, AskOffset
Tick Offset	Param	Number of ticks to offset (0-10)
Tick Size	ParamList	0.01, 0.05, 0.1, 0.2, 0.25, 0.5, 1, 5, 10, 25
Max Retries	Param	Maximum modification attempts (1-10, default: 3)
Retry Delay	Param	Seconds between status checks (1-10, default: 1)

Trigger Buttons

Button	Action
Place BUY Limit	Initiates BUY order at calculated price
Place SELL Limit	Initiates SELL order at calculated price
Cancel Order	Manually cancels active order
Reset Module	Clears all state and returns to IDLE

---

Price Calculation Modes

Mode	Calculation	Use Case
MidPrice	(Bid + Ask) / 2 rounded to tick	Balanced approach, potential price improvement
BestBid	Bid price	Passive BUY, join the queue
BestAsk	Ask price	Passive SELL, join the queue
BidOffset	Bid + (N × TickSize)	Aggressive BUY, higher fill probability
AskOffset	Ask - (N × TickSize)	Aggressive SELL, higher fill probability

All prices are rounded to the nearest tick size for exchange compliance.

---

API Endpoints Used

API	Endpoint	Purpose
Quotes	POST /api/v1/quotes	Fetch real-time bid/ask/ltp
PlaceOrder	POST /api/v1/placeorder	Place limit order
OrderStatus	POST /api/v1/orderstatus	Check order fill status
ModifyOrder	POST /api/v1/modifyorder	Update order price
CancelOrder	POST /api/v1/cancelorder	Cancel pending order

---

API Call Sequence

┌─────────────────────────────────────────────────────────────────┐
│  STEP 1: Fetch Quote                                            │
│  POST /api/v1/quotes → Get bid, ask, ltp                        │
│  Calculate limit price based on selected mode                   │
│  Round to nearest tick size                                     │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│  STEP 2: Place Limit Order                                      │
│  POST /api/v1/placeorder                                        │
│  pricetype: "LIMIT", price: calculated price                    │
│  Store: orderID                                                 │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│  STEP 3: Check Order Status (after retry delay)                 │
│  POST /api/v1/orderstatus                                       │
│  Read: order_status (complete/open/rejected/cancelled)          │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│  STEP 4: Modify Order (if open and retry < max)                 │
│  POST /api/v1/quotes → Fetch fresh bid/ask                      │
│  POST /api/v1/modifyorder → Update price                        │
│  Increment retry counter, loop back to Step 3                   │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│  STEP 5: Cancel Order (after max retries exhausted)             │
│  POST /api/v1/cancelorder                                       │
│  Final status check after retry delay                           │
└─────────────────────────────────────────────────────────────────┘

---

Static Variables

Order Tracking

Variable	Type	Purpose
LimitExec_State	Numeric	Current state machine state
LimitExec_OrderID	Text	Active order ID
LimitExec_Action	Text	BUY or SELL
LimitExec_OrderStatus	Text	Last known order status
LimitExec_Message	Text	User-facing status message
LimitExec_RetryCount	Numeric	Current retry attempt
LimitExec_LastActionTime	Numeric	Timestamp of last action

Price Data

Variable	Type	Purpose
LimitExec_Bid	Numeric	Current bid price
LimitExec_Ask	Numeric	Current ask price
LimitExec_LTP	Numeric	Last traded price
LimitExec_MidPrice	Numeric	Calculated mid price (tick-rounded)
LimitExec_QuoteTime	Numeric	Last quote fetch timestamp

Order Details

Variable	Type	Purpose
LimitExec_OrderPrice	Numeric	Price at which order was placed/modified
LimitExec_FilledPrice	Numeric	Average fill price (if complete)

---

GFX Dashboard Layout

┌────────────────────────────────────────────────────────────┐
│       LIMIT ORDER EXECUTION - SYMBOL (EXCHANGE)            │
├────────────────────────────────────────────────────────────┤
│                    MARKET DATA                             │
├──────────────┬───────────────────────┬─────────────────────┤
│     BID      │         LTP           │        ASK          │
│   5765.00    │       5766.00         │      5767.00        │
├──────────────┼───────────────────────┼─────────────────────┤
│     MID      │       5766.00         │  SPREAD  │   2.00   │
├──────────────┴───────────────────────┴─────────────────────┤
│                    ORDER STATUS                            │
├──────────────┬─────────────────────────────────────────────┤
│    STATE     │              ORDER ID                       │
│  MONITORING  │         250828000185002                     │
├──────────────┼──────────────┼──────────────┼───────────────┤
│   ACTION     │    PRICE     │    RETRY     │    FILLED     │
│     BUY      │   5766.00    │    1 / 3     │     ---       │
├──────────────┴──────────────┴──────────────┴───────────────┤
│  Modified @ 5766.00. Monitoring...                         │
├────────────────────────────────────────────────────────────┤
│  Mode: MidPrice | Tick: 1 | Qty: 1 | Product: MIS          │
└────────────────────────────────────────────────────────────┘

---

Color Coding

Element	Color	Meaning
Bid Price/BUY Action	Dark Green	Buy side
Ask Price/SELL Action	Dark Red	Sell side
LTP	Yellow	Last traded price
State: COMPLETE	Dark Green	Order filled successfully
State: MONITORING/MODIFYING	Dark Yellow	Order in progress
State: CANCELED/REJECTED	Dark Red	Order failed or canceled
State: IDLE	Grey	No active order

---

Error Handling

Scenario	Action
Invalid API Key	Display warning, disable all API calls
API call fails	Log error, proceed to next state
Order rejected	Set state to REJECTED, display message
Order cancelled by broker	Set state to REJECTED, display message
Modify fails	Move to CANCELING state
Max retries exhausted	Auto-cancel pending order
Cancel fails	Move to CANCELED state (assumed)
Filled during cancel	Set state to COMPLETE

---

Timing Control

Event	Interval
Quote Refresh	Every 2 seconds (when API key valid)
Chart Refresh	Every 1 second (RequestTimedRefresh)
Status Check	After configurable retry delay (default: 1 sec)
State Transitions	Immediate upon condition met

---

Safety Features

1. API Key Validation: No API calls made if key is default or less than 10 characters

2. State Protection: BUY/SELL triggers only work in IDLE state

3. Manual Override: Cancel button works in any active state

4. Reset Function: Clears all state for fresh start

5. Automatic Cleanup: Orders auto-canceled after max retries

6. Final Check: Verifies fill status after cancel to avoid missed fills

---

Instrument Configuration Guide

Instrument Type	Exchange	Recommended Tick Size
Equity	NSE/BSE	0.05
Equity F&O	NFO/BFO	0.05
Currency Futures	CDS	0.0025
Crude Oil	MCX	1
Natural Gas	MCX	0.1
Gold	MCX	1
Silver	MCX	1

---

Version History

Version	Date	Changes
1.0	Nov 2025	Initial release with 5 price modes, state machine, GFX dashboard