main.py

"""
source: https://dailypythonprojects.substack.com/p/build-a-pdf-toolkit-with-python-day

The project:
PDF merger to merge PDFs
PDF splitter to split pages
rotate pages
compress PDFs to reduce file size
web app
"""
import argparse
import logging
import sys

from pdf_tools.cli.parser import parse_arguments
from pdf_tools.operations.merge import (
    MergeOperation, 
    MergeConfig, 
    MergeResult, 
    OperationError,
)
from pdf_tools.operations.rotate import (
    RotateConfig,
    RotateOperation,
    RotateResult,
)

def configure_logging() -> None:
    """Configure basic logging for the CLI application."""
    logging.basicConfig(
        level=logging.INFO,
        format="%(levelname)s - %(name)s - %(message)s",
        #datefmt="%Y-%m-%d %H:%M:%S",
    )

def handle_merge(args: argparse.Namespace) -> int:
    """
    Handle the merge operation based on parsed CLI arguments.
    
    - building `MergeConfig` is the translation layer between CLI and operation.
    - the operation stays clean and independent of how the data was obtained.
    """
    config = MergeConfig(
        input_folder=args.path,
        output_filename=args.output,
    )
    operation = MergeOperation(config)

    try:
        result: MergeResult = operation.run()
    except OperationError as e:
        print(f"Error: {e}", file=sys.stderr)
        return 1

    # Success path - print a CLI-friendly summary of the operation
    print(f"Found {len(result.input_files)} PDF file(s):")
    for pdf in result.input_files:
        print(f"  - {pdf}")

    print(
        f"Success! Merged {len(result.input_files)} files "
        f"with ({result.total_pages} pages) into '{result.output_file}'"
    )

    return 0

#def handle_split(args: argparse.Namespace) -> int:
    """Handle the split operation based on parsed CLI arguments."""

def handle_rotate(args: argparse.Namespace) -> int:
    """Handle the rotate operation based on parsed CLI arguments."""
    config = RotateConfig(
        input_file=args.input,
        output_filename=args.output,
        pages_to_rotate=args.pages,
        angle=90,
    )
    operation = RotateOperation(config)

    try:
        result = operation.run()
    except OperationError as e:
        print(f"Error: {e}", file=sys.stderr)
        return 1
    
    print(
        f"Success! Rotated {len(result.pages_rotated)} page(s) "
        f"in: '{result.input_file}' -> out: '{result.output_file}'"
    )
    return 0

#def handle_compress(args: argparse.Namespace) -> int:
    

def main(argv: list[str] | None = None) -> int:
    configure_logging()
    print("===== PDF Tools =====")

    args = parse_arguments(argv)  #see parser.py

    if args.command == "merge":   #.commands comes from parser.py subparsers container
        return handle_merge(args)
    
    if args.command == "rotate":
        return handle_rotate(args)

    # fallback
    print(f"Unknown command: {getattr(args, 'command', None)}", file=sys.stderr)
    return 1
 

if __name__ == "__main__":
    raise SystemExit(main())