# 📋 QUICK REFERENCE CARD - Aplikasi Absensi Akademik

## 🚀 Quick Start

### 1. Build & Run
```bash
cd /Users/maccomputer/AndroidStudioProjects/Starter-EAS-2025-2026
./gradlew clean build
./gradlew installDebug
```

### 2. First Login
- NPM: (register dulu)
- Password: (sesuai pilihan)

### 3. Test Absensi
- Allow location & camera permissions
- Ambil foto
- Kirim absensi (otomatis validate lokasi)
- Lihat riwayat

---

## 🔧 Key Configuration Points

### Campus Location
**File**: `MainActivity.kt` (line ~70)
```kotlin
campusLat: Double = -6.2030,    // Ubah ini
campusLon: Double = 107.0045,   // Ubah ini
radiusMeters: Float = 100f      // Ubah ini (meter)
```

### Webhook URL
**File**: `MainActivity.kt` (line ~110)
```kotlin
val url = URL("https://n8n.lab.ubharajaya.ac.id/webhook/...")
```

### Database Version
**File**: `DatabaseHelper.kt` (line ~12)
```kotlin
private const val DATABASE_VERSION = 2
```

---

## 📱 Screen Navigation

```
LOGIN ←→ REGISTER
  ↓
ABSENSI (ambil foto + lokasi)
  ├─ Kirim (validate lokasi → webhook)
  └─ Lihat Riwayat → HISTORY (list)
```

---

## 📊 Database Schema

### Users Table
```sql
id | username | npm (UNIQUE) | password
```

### Attendance Table (NEW)
```sql
id | npm (FK) | timestamp | latitude | longitude | status
```

**Status Values**: 
- `"success"` - dalam radius
- `"invalid_location"` - diluar radius

---

## 🔨 Main Functions

### Location Functions
```kotlin
calculateDistance(lat1, lon1, lat2, lon2): Float
↓ Hitung jarak dalam meter

isWithinAbsensiRadius(studentLat, studentLon, ...): Boolean
↓ Cek apakah dalam radius absensi

obfuscateCoordinates(lat, lon, offset): Pair<Double, Double>
↓ Obfuscate koordinat untuk privacy
```

### Database Functions
```kotlin
db.addAttendanceRecord(npm, timestamp, lat, lon, status): Boolean
↓ Simpan record absensi

db.getAttendanceHistory(npm): List<AttendanceRecord>
↓ Ambil riwayat absensi
```

### Network Functions
```kotlin
kirimKeN8n(context, db, npm, nama, lat, lon, foto)
↓ Send data ke webhook dengan validasi
```

---

## ⚡ Common Tasks

### Ubah Lokasi Campus
Edit `MainActivity.kt` line ~68:
```kotlin
fun isWithinAbsensiRadius(
    studentLat: Double,
    studentLon: Double,
    campusLat: Double = -6.2030,   // CHANGE THIS
    campusLon: Double = 107.0045,  // CHANGE THIS
    radiusMeters: Float = 100f     // CHANGE THIS
)
```

### Ubah Radius
```kotlin
radiusMeters: Float = 200f  // Ganti 100 menjadi 200
```

### Ubah Webhook URL
Edit `MainActivity.kt` line ~110:
```kotlin
val url = URL("https://your-webhook-url-here")
```

### Clear Database
```bash
adb shell pm clear id.ac.ubharajaya.sistemakademik
```

### View Database
```bash
adb pull /data/data/id.ac.ubharajaya.sistemakademik/databases/Akademik.db
```

---

## 🧪 Testing Quick Checklist

- [ ] Register user baru
- [ ] Login dengan NPM/password
- [ ] Ambil foto (grant camera permission)
- [ ] Check lokasi (grant location permission)
- [ ] Kirim absensi
- [ ] Verifikasi di database:
  - [ ] Attendance record tersimpan
  - [ ] Status = "success" atau "invalid_location"
  - [ ] Timestamp correct
- [ ] Lihat riwayat
  - [ ] List muncul
  - [ ] Status indicator (✓/✗) benar
  - [ ] Tanggal format Indonesia

---

## 🐛 Debugging Tips

### View Logs
```bash
adb logcat id.ac.ubharajaya.sistemakademik:V *:S
```

### Check Database Content
```bash
adb shell
sqlite3 /data/data/id.ac.ubharajaya.sistemakademik/databases/Akademik.db
> SELECT * FROM users;
> SELECT * FROM attendance;
> .quit
```

### Test Permission
```bash
adb shell pm grant id.ac.ubharajaya.sistemakademik android.permission.ACCESS_FINE_LOCATION
adb shell pm grant id.ac.ubharajaya.sistemakademik android.permission.CAMERA
```

---

## 📦 Dependencies

```gradle
// Core
androidx.core:core-ktx
androidx.activity:activity-compose:1.9.0

// Compose
androidx.compose.ui
androidx.compose.material3
androidx.compose.material:material-icons-extended:1.6.0

// Location
com.google.android.gms:play-services-location:21.0.1
```

---

## 📂 Project Structure

```
app/
├── src/main/
│   ├── java/id/ac/ubharajaya/sistemakademik/
│   │   ├── MainActivity.kt (main app, all screens)
│   │   └── DatabaseHelper.kt (database operations)
│   ├── res/
│   │   ├── values/ (strings, colors, themes)
│   │   ├── layout/ (compose layouts)
│   │   └── drawable/ (icons, images)
│   └── AndroidManifest.xml (permissions, activities)
├── build.gradle.kts (dependencies, build config)
└── ...
```

---

## 🔐 Permissions Required

```xml
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.CAMERA"/>
```

---

## 📈 Useful Metrics

| Metric | Value |
|--------|-------|
| Min SDK | 28 |
| Target SDK | 36 |
| Compile SDK | 36 |
| Java Version | 11 |
| Default Radius | 100 meters |
| Photo Quality | 80% JPEG |
| DB Version | 2 |

---

## 🎯 Data Flow Summary

```
User Input
    ↓
Validate (location, photo)
    ↓
Save to Local DB
    ↓
Send to Webhook (n8n)
    ↓
Show Feedback
    ↓
Update History UI
```

---

## 💡 Tips & Tricks

1. **Testing Location**: 
   - Use Android Emulator's extended controls to simulate location
   - Or physically go ke lokasi yang valid

2. **Debugging Photo**:
   - Photo tersimpan sebagai Bitmap in-memory
   - Convert to Base64 untuk webhook
   - Tidak di-save ke storage (enhancement needed)

3. **Database Testing**:
   - Pull database dan buka di SQLite browser
   - Check attendance records dan status values
   - Verify foreign key relationships

4. **Network Testing**:
   - Monitor network calls di Android Studio Profiler
   - Check webhook responses di n8n dashboard
   - Use packet sniffer (tcpdump) untuk HTTPS analysis

---

## 🚨 Common Issues & Solutions

| Issue | Solution |
|-------|----------|
| Location null | Grant permission, wait for GPS lock |
| Photo not captured | Check camera permission, device has camera |
| Webhook timeout | Check internet, verify URL |
| DB migration error | Clear app data, reinstall |
| Permission denied | Grant at runtime, check manifest |

---

## 📚 Documentation Files

| File | Content |
|------|---------|
| `DEVELOPMENT_GUIDE.md` | User guide, features, setup |
| `CHANGELOG.md` | Version history, detailed changes |
| `IMPLEMENTATION_NOTES.md` | Technical config, debugging |
| `IMPLEMENTATION_SUMMARY.md` | Project summary, metrics |
| `QUICK_REFERENCE.md` | This file - quick lookup |

---

## 🔗 Important URLs

- **Webhook Test**: https://n8n.lab.ubharajaya.ac.id/webhook-test/...
- **Webhook Prod**: https://n8n.lab.ubharajaya.ac.id/webhook/...
- **Ntfy Monitoring**: https://ntfy.ubharajaya.ac.id/EAS
- **Spreadsheet Tracking**: https://docs.google.com/spreadsheets/d/1jH15MfnNgpPGuGeid0hYfY7fFUHCEFbCmg8afTyyLZs/

---

**Last Updated**: 14 January 2026
**Version**: 1.1.0
**For**: Aplikasi Absensi Akademik Berbasis Koordinat dan Foto