# Label Printing - New Features Guide

## Overview

The label printer now supports:
1. **Multiple Templates** - Choose between OK and NOK labels
2. **Multiple Copies** - Print multiple labels in one operation

## File Format

The monitored file (`check.txt`) now supports an extended format:

```
ARTICLE;NR_ART;SERIAL;TEMPLATE_TYPE;COUNT
```

### Parameters

| Parameter | Position | Description | Values | Default |
|-----------|----------|-------------|--------|---------|
| ARTICLE | 1 | Article/Command number | Any text | Required |
| NR_ART | 2 | Article number | Any text | Required |
| SERIAL | 3 | Serial number | Any text | Required |
| TEMPLATE_TYPE | 4 | Template selection | 0 = OK, 1 = NOK | 0 (OK) |
| COUNT | 5 | Number of copies | 1-100 | 1 |

## Templates

### Template Files

- `conf/label_template_ok.svg` - Template for OK labels (TEMPLATE_TYPE=0)
- `conf/label_template_nok.svg` - Template for NOK labels (TEMPLATE_TYPE=1)
- `conf/label_template.svg` - Default fallback template

### Customizing Templates

Edit the SVG files to customize the layout:
- Both templates use the same variables: `{Article}`, `{NrArt}`, `{Serial}`
- Modify colors, fonts, or layout as needed
- Keep dimensions at 35mm × 25mm (landscape)

## Usage Examples

### Example 1: Print 1 OK Label
```
COM-2024-001;ART-12345;SN-20260213-001;0;1
```

### Example 2: Print 3 OK Labels
```
COM-2024-002;ART-67890;SN-20260213-002;0;3
```

### Example 3: Print 1 NOK Label
```
COM-2024-003;ART-11111;SN-20260213-003;1;1
```

### Example 4: Print 5 NOK Labels
```
COM-2024-004;ART-22222;SN-20260213-004;1;5
```

### Example 5: Backward Compatibility (Old Format)
```
COM-2024-005;ART-33333;SN-20260213-005
```
This will default to OK template with 1 copy.

## Testing

### Quick Test

1. **Start the application**:
   ```powershell
   .\venv\Scripts\python.exe label_printer_gui.py
   ```

2. **Select your printer** in the GUI

3. **Edit the monitored file** (default: `C:\Users\Public\Documents\check.txt`):
   ```
   TEST-OK;123456;SN-001;0;2
   ```

4. **Save the file** - The app will automatically:
   - Detect OK template (type=0)
   - Print 2 copies

5. **Test NOK template**:
   ```
   TEST-NOK;789012;SN-002;1;1
   ```

### PDF Testing

Use "Microsoft Print to PDF" to test without physical printer:
- Select "Microsoft Print to PDF" in the GUI
- PDFs will be saved to `pdf_backup/` folder
- Check that the correct template was used

## Workflow

```
File Modified
    ↓
Read Parameters (Article, NrArt, Serial, Template, Count)
    ↓
Select Template (OK or NOK)
    ↓
For each copy (1 to Count):
    ├─ Generate PDF from SVG template
    ├─ Replace variables {Article}, {NrArt}, {Serial}
    ├─ Save to pdf_backup/
    └─ Print via SumatraPDF
    ↓
Clear file (write "-")
    ↓
Show success message
```

## Safety Limits

- **Maximum copies**: 100 per operation
- **Minimum copies**: 1
- Invalid values default to 1 copy

## Troubleshooting

### Template Not Found
- **Symptom**: Message "Using SVG template: conf/label_template.svg"
- **Cause**: `label_template_ok.svg` or `label_template_nok.svg` missing
- **Fix**: Ensure both template files exist in `conf/` folder

### Wrong Template Printed
- **Symptom**: NOK template used when OK expected
- **Cause**: TEMPLATE_TYPE parameter incorrect
- **Fix**: Check 4th parameter is 0 for OK, 1 for NOK

### Only 1 Label Printed
- **Symptom**: COUNT parameter ignored
- **Cause**: Invalid COUNT value or missing parameter
- **Fix**: Ensure 5th parameter is a number between 1-100

## Technical Details

### File Parsing

The system tries:
1. **Semicolon format**: `value1;value2;value3;value4;value5`
2. **Key=value format** (fallback):
   ```
   article=COM-2024-001
   nr_art=ART-12345
   serial=SN-001
   template=0
   count=3
   ```

### Multiple Copy Handling

- Each label is printed sequentially
- 0.5 second delay between copies
- Progress shown in GUI for multiple copies
- All copies use the same PDF template

### Backward Compatibility

Old format (3 parameters) still works:
```
ARTICLE;NR_ART;SERIAL
```
Automatically uses: OK template, 1 copy

## Log Files

Print actions are logged to `logs/print_log_YYYYMMDD.csv`:
- Date/Time
- Article, NrArt, Serial
- Printer name
- PDF filename
- Template used
- Number of copies
- Success/Failure status

---

**Version**: February 2026  
**Compatible with**: Citizen CTS-310, Zebra ZD420/ZD421