# MT4 EA Implementation - Quick Summary

**Full Plan:** [mt4-ea-implementation-plan.md](./mt4-ea-implementation-plan.md)  
**Date:** November 4, 2025

---

## Overview

Creating a **Multi-Timeframe Zone Expert Advisor for MT4** that implements the Strategy.md requirements:
- H4 zone detection (4 pattern types)
- M30 confirmation zones
- M15 entry zones
- Automated trade execution

---

## Architecture Decision: Monolithic with Parallel Arrays

**Why not OOP?**
- MT4 has unreliable support for dynamic arrays of structs
- Proven approach from `FINAL_H4_ZONES.mq4` uses parallel arrays
- Simpler debugging and maintenance for single-file EA

**Data Structure:**
```mql4
// H4 Zone Storage (50 max)
double h4_ZoneHighs[50];
double h4_ZoneLows[50];
datetime h4_ZoneTimes[50];
bool h4_ZoneIsReversed[50];
string h4_ZoneTypes[50];
bool h4_ZoneMonitoringM30[50];
int h4_M30ChildIndex[50];
int h4_ZoneCount = 0;

// M30 Zone Storage (100 max) - similar structure
// M15 Zone Storage (200 max) - similar structure + order tickets
```

---

## 10 Implementation Phases

| Phase | Focus | Deliverable | Hours |
|-------|-------|-------------|-------|
| 1 | Infrastructure | Working skeleton EA | 2 |
| 2 | Bar Detection | New bar detection all TFs | 1 |
| 3 | Pattern Logic | Port from MQ4 indicator | 3 |
| 4 | H4 Zones | Create, reverse, delete | 4 |
| 5 | M30 Zones | Monitoring & confirmation | 4 |
| 6 | M15 Zones | Entry detection & orders | 6 |
| 7 | Order Management | Monitor & lifecycle | 3 |
| 8 | Visual Display | Zones + info panel | 3 |
| 9 | Error Handling | Validation & logging | 2 |
| 10 | Testing | Strategy tester validation | 4-10 |

**Total Estimate:** 20-30 hours

---

## Critical Corrections to Strategy

### Order Type Correction
**Strategy states:** "Place Buy Limit at zone High"  
**Problem:** Limit orders are BELOW current price for buys  
**Solution:** Use **Buy Stop** at High and **Sell Stop** at Low

### Stop Loss Placement
**Strategy:** "SL at zone boundary"  
**Implementation:** SL = zone boundary ± StopLossPips buffer  
Example: Buy Stop at High, SL at (Low - StopLossPips×Point)

---

## Key Features

### H4 Level
✅ 4 pattern types (Regular/Irregular Buy/Sell)  
✅ Zone lifecycle: Create → Break → Reverse → Break → Delete  
✅ Dashed rectangles → Solid on reversal  
✅ Visible on all timeframes

### M30 Level  
✅ Monitors only when price enters H4 zone  
✅ Checks only NEW bars after entry  
✅ One-break deletion (no reversal)  
✅ Links to parent H4 zone

### M15 Level
✅ Monitors only when price enters M30 zone  
✅ Places pending order immediately  
✅ One trade per M15 zone  
✅ Links to parent M30 zone

### Order Management
✅ Buy Stop at M15 High, SL at M15 Low  
✅ Sell Stop at M15 Low, SL at M15 High  
✅ TP calculated from input pips  
✅ Cancels orders when parent zones break

---

## MT4 Compatibility Notes

**What we CAN'T use (MQL5 only):**
- ❌ Classes and objects
- ❌ `CTrade` library
- ❌ `MqlRates[]` structures
- ❌ `CopyRates()` function
- ❌ Position concept

**What we WILL use:**
- ✅ Parallel arrays
- ✅ Global functions
- ✅ `iOpen/iClose/iHigh/iLow`
- ✅ `OrderSend()` directly
- ✅ Order ticket tracking
- ✅ Simple structs (for data passing only)

---

## Testing Strategy

### Per-Phase Testing
Each phase must pass before moving to next:
- Phase 3: Compare pattern detection with original indicator
- Phase 4: Test H4 zone lifecycle manually
- Phase 5: Verify M30 monitoring triggers correctly
- Phase 6: Verify order placement with correct parameters

### Integration Testing
- Full cascade: H4 → M30 → M15 → Order
- Multiple concurrent zones
- Zone break cascades
- Reversal handling

### Strategy Tester
- 3+ months historical data
- Visual mode verification
- Multiple scenario testing
- Edge case validation

---

## Input Parameters

```mql4
input double LotSize = 0.01;           // Fixed lot size
input int StopLossPips = 30;           // Additional SL buffer
input int TakeProfitPips = 60;         // TP distance
input int MagicNumber = 123456;        // EA identifier
input int Slippage = 3;                // Max slippage
input int RecentBarsToCheck = 10;     // Pattern scan depth
input bool EnableDebugLogs = false;    // Console logging
```

---

## Function Organization

### Main Flow
```
OnTick()
├─► CheckNewBars() → ProcessH4/M30/M15
├─► CheckH4ZoneEntries() → Start M30 monitoring
├─► CheckM30ZoneEntries() → Start M15 monitoring
├─► MonitorPendingOrders() → Track execution
└─► UpdateDisplay() → Refresh visuals
```

### Pattern Detection (Reusable)
```
IsRegularBuy(ENUM_TIMEFRAMES tf, int index)
IsIrregularBuy(ENUM_TIMEFRAMES tf, int index)
IsRegularSell(ENUM_TIMEFRAMES tf, int index)
IsIrregularSell(ENUM_TIMEFRAMES tf, int index)
```

### Zone Management (Per Timeframe)
```
H4: Create, Reverse, Delete, Draw
M30: Create, Delete, Draw
M15: Create, Draw, PlaceOrder
```

---

## Risk Considerations

### Limitations
- Fixed lot size (no dynamic risk management)
- Array size limits (50/100/200 per TF)
- No trade management (trailing, breakeven)
- No session filters

### Safety Features
- Magic number isolation
- One trade per M15 zone
- Input validation
- Comprehensive error logging
- Order cancellation on parent breaks

---

## Success Criteria

**Must Have:**
- ✅ All 4 patterns detected correctly
- ✅ Full H4 → M30 → M15 cascade works
- ✅ Orders placed with correct parameters
- ✅ Zone lifecycle managed properly
- ✅ Visual display accurate
- ✅ No runtime errors in tester

**Nice to Have:**
- Code comments and documentation
- Debug logging system
- Info panel with stats
- Clean code organization

---

## Next Steps

1. **Review Plan:** Approve implementation approach
2. **Start Phase 1:** Create EA skeleton (2 hours)
3. **Incremental Development:** Complete phases 2-10 sequentially
4. **Continuous Testing:** Validate each phase before proceeding
5. **Final Testing:** Full strategy tester validation
6. **Demo Deployment:** Live testing on demo account

---

## File Location

```
MQL4/
└── Experts/
    └── _Thivyam/
        └── MultiTimeframeZone/
            └── MultiTimeframeZoneEA_MT4.mq4  (single file)
```

---

## Development Timeline

**Week 1:** Phases 1-4 (Infrastructure + H4 zones)  
**Week 2:** Phases 5-6 (M30/M15 zones + orders)  
**Week 3:** Phases 7-8 (Management + display)  
**Week 4:** Phases 9-10 (Testing + refinement)

**Minimum Viable Product:** End of Week 2  
**Production Ready:** End of Week 4

---

## Support Documentation

- **Full Implementation Plan:** mt4-ea-implementation-plan.md (50+ pages)
- **Reference Code:** FINAL_H4_ZONES.mq4 (pattern detection)
- **Strategy Rules:** Strategy.md (requirements)
- **MQ4 vs MQ5 Analysis:** COMPARISON_MQ4_vs_MQ5.md (architecture insights)

---

**Status:** Ready for Development  
**Risk:** Medium (complex multi-TF logic)  
**Confidence:** High (proven pattern logic + clear plan)

---

**Quick Reference During Development:**

**Phase 1-2:** Focus on bar detection infrastructure  
**Phase 3:** Port pattern detection from indicator  
**Phase 4:** Build H4 zone lifecycle  
**Phase 5-6:** Add M30/M15 cascade  
**Phase 7:** Add order execution  
**Phase 8-10:** Polish and test

**Remember:** Test each phase thoroughly before moving forward!

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**End of Quick Summary**