# z/OS CCSID Converter Package - Summary

## Package Overview

The `zos-ccsid-converter` package has been successfully refactored from the original `ebcdic_converter_fcntl.py` script into a pip-installable Python package for distribution to customers. The package name reflects its general-purpose nature for working with z/OS code pages (CCSID), though it currently focuses on ASCII/EBCDIC conversion.

## Package Structure

```
zos_ccsid_converter/
├── setup.py                           # Package configuration
├── pyproject.toml                     # Modern Python packaging metadata
├── MANIFEST.in                        # File inclusion rules
├── LICENSE                            # Apache 2.0 license
├── README.md                          # Complete documentation
├── PACKAGE_SUMMARY.md                 # This file
├── zos_ccsid_converter/              # Main package directory
│   ├── __init__.py                   # Package exports
│   ├── converter.py                  # Core conversion logic
│   └── cli.py                        # Command-line interface
├── tests/                             # Test suite
│   └── test_ebcdic_converter.py      # Comprehensive tests (10 tests)
└── examples/                          # Usage examples
    └── example_service_usage.py      # 7 working examples
```

## Installation Instructions

### Option 1: Install from Source Directory

```bash
cd etc/install/base/uss_build/zos_ccsid_converter
pip install .
```

### Option 2: Build and Install Distribution Package

```bash
# Install build tools (if not already installed)
pip install build

# Build the package
python -m build

# Install from wheel
pip install dist/zos_ccsid_converter-1.0.0-py3-none-any.whl
```

### Option 3: Install in Development Mode

```bash
# For development/testing
pip install -e .
```

## Usage After Installation

### Command Line Interface

```bash
# Convert a file
zos-ccsid-converter input.txt output.txt

# With verbose output
zos-ccsid-converter -v input.txt output.txt

# Show help
zos-ccsid-converter --help
```

### Python API - Library Usage

```python
from zos_ccsid_converter import CodePageService

# Initialize service
service = CodePageService()

# Detect encoding
ccsid = service.get_ccsid('/path/to/file')
encoding = service.get_encoding_name('/path/to/file')

# Check file type
if service.is_ascii('/path/to/file'):
    print("File is ASCII")

# Convert data
ebcdic_bytes = service.convert_to_ebcdic(b"Hello World")
ascii_bytes = service.convert_to_ascii(ebcdic_bytes)

# Convert files
stats = service.convert_file('/input.txt', '/output.txt')
if stats['success']:
    print(f"Converted {stats['bytes_read']} bytes")
```

### Convenience Functions

```python
from zos_ccsid_converter import (
    detect_code_page,
    detect_encoding,
    convert_data,
    CCSID_ISO8859_1,
    CCSID_IBM1047,
    CCSID_UNTAGGED
)

# Quick detection
ccsid = detect_code_page('/tmp/file.txt')
encoding = detect_encoding('/tmp/file.txt')

# Quick conversion
ebcdic = convert_data(b"Hello", 'ISO8859-1', 'IBM-1047')
```

## Testing

```bash
# Run comprehensive test suite
cd tests
python3 test_ebcdic_converter.py

# With verbose output
python3 test_ebcdic_converter.py --verbose

# Keep test files for inspection
python3 test_ebcdic_converter.py --keep-files
```

**Test Results:** All 10 tests pass on z/OS

## Key Features

1. **Native z/OS fcntl Integration**
   - Uses F_CONTROL_CVT (13) for encoding detection
   - Uses F_SETTAG (12) for file tagging
   - Direct system calls (no subprocess overhead)

2. **Proper Big-Endian Support**
   - Uses `ctypes.BigEndianStructure` for z/OS byte order
   - Correct handling of f_cnvrt and attrib_t structures

3. **Comprehensive API**
   - CodePageService class for object-oriented usage
   - Convenience functions for quick operations
   - Both CLI and library interfaces

4. **Robust Error Handling**
   - Graceful handling of unconvertible characters
   - Detailed error messages
   - Comprehensive conversion statistics

5. **Well Tested**
   - 10 comprehensive tests covering:
     - Regular files (ISO8859-1, IBM-1047, untagged)
     - Named pipes (FIFOs)
     - Empty files
     - Special characters
     - Large files (~100KB)
     - Error conditions

## Distribution to Customers

### Option 1: Source Distribution

Provide the entire `zos_ccsid_converter/` directory to customers with instructions:

```bash
# Customer installs from source
cd zos_ccsid_converter
pip install .
```

### Option 2: Built Distribution Packages

Build and distribute wheel/tarball:

```bash
# Build packages
python -m build

# Distribute these files to customers:
# - dist/zos_ccsid_converter-1.0.0-py3-none-any.whl
# - dist/zos_ccsid_converter-1.0.0.tar.gz

# Customer installs from wheel
pip install zos_ccsid_converter-1.0.0-py3-none-any.whl
```

### Option 3: Private PyPI Repository

Upload to a private PyPI server for easy installation:

```bash
# Customer installs from private PyPI
pip install zos-ccsid-converter --index-url https://your-pypi-server.com/simple
```

## Migration from Original Script

### Old Usage (ebcdic_converter_fcntl.py)

```python
import ebcdic_converter_fcntl as converter

service = converter.CodePageService()
ccsid = service.get_ccsid('/path/to/file')
```

### New Usage (Package)

```python
from zos_ccsid_converter import CodePageService

service = CodePageService()
ccsid = service.get_ccsid('/path/to/file')
```

**Changes Required:**
- Update import statements from `import ebcdic_converter_fcntl` to `from zos_ccsid_converter import ...`
- All functionality remains the same
- CLI command changes from `./ebcdic_converter_fcntl.py` to `zos-ccsid-converter`

## Files Included in Package

### Core Package Files
- `zos_ccsid_converter/__init__.py` - Package initialization and exports
- `zos_ccsid_converter/converter.py` - Core conversion logic (from original script)
- `zos_ccsid_converter/cli.py` - Command-line interface (extracted from original)

### Configuration Files
- `setup.py` - Package metadata and dependencies
- `pyproject.toml` - Modern Python packaging configuration
- `MANIFEST.in` - File inclusion rules for distribution

### Documentation
- `README.md` - Complete package documentation
- `LICENSE` - Apache 2.0 license
- `PACKAGE_SUMMARY.md` - This summary

### Tests and Examples
- `tests/test_ebcdic_converter.py` - Comprehensive test suite
- `examples/example_service_usage.py` - 7 usage examples

## Original Files (Preserved)

The original implementation files are preserved in `etc/install/base/uss_build/bin/`:
- `ebcdic_converter_fcntl.py` - Original script
- `test_ebcdic_converter.py` - Original tests
- `example_service_usage.py` - Original examples
- `README_ebcdic_converter.md` - Original documentation

## Version Information

- **Package Name:** zos-ccsid-converter
- **Version:** 1.0.0
- **Python Requirement:** >=3.6
- **Platform:** z/OS
- **License:** Apache 2.0

## Support and Maintenance

For issues or questions:
1. Refer to README.md for complete documentation
2. Check examples/ directory for usage patterns
3. Run tests/ to verify installation
4. Contact package maintainers

## Next Steps for Customers

1. **Install the package:**
   ```bash
   pip install zos-ccsid-converter
   ```

2. **Verify installation:**
   ```bash
   zos-ccsid-converter --help
   python3 -c "from zos_ccsid_converter import CodePageService; print('OK')"
   ```

3. **Run tests:**
   ```bash
   cd tests
   python3 test_ebcdic_converter.py
   ```

4. **Review examples:**
   ```bash
   cd examples
   python3 example_service_usage.py
   ```

5. **Integrate into your code:**
   - Update imports
   - Use CodePageService API
   - Or use CLI command

## Summary

The EBCDIC converter has been successfully packaged for distribution:

✅ Package structure created with proper Python packaging standards
✅ Code split into library (converter.py) and CLI (cli.py)
✅ Entry point configured for `zos-ccsid-converter` command
✅ Tests and examples updated with new import paths
✅ Complete documentation provided
✅ Apache 2.0 license included
✅ Ready for pip installation and distribution

The package is ready to be distributed to customers via source distribution, built packages, or private PyPI repository.