utils.py mit eingecheckt. Beispieldatei aus Config erzeugen.

lib/utils.py

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+"""
+Common utility functions for the cable routing system.
+
+This module contains frequently used helper functions for:
+- File and path operations
+- Environment variable handling
+- JSON operations
+- DXF file handling
+- Dictionary operations
+"""
+
+import json
+import os
+import sys
+from pathlib import Path
+from typing import Any, Tuple
+
+import ezdxf
+from ezdxf.lldxf.const import DXFStructureError
+
+
+# ============================================================================
+# File Operations
+# ============================================================================
+
+def check_file_in_work(work_dir, filename) -> Tuple[Path, bool]:
+    """
+    Check if a file exists, either at the given path or in the work directory.
+
+    Args:
+        work_dir: Working directory to check if file not found at filename path (str or Path)
+        filename: Path to the file to check (str or Path)
+
+    Returns:
+        Tuple of (resolved_path, exists_flag)
+        - resolved_path: Path where file was found (or would be)
+        - exists_flag: True if file exists, False otherwise
+    """
+    work_dir = Path(work_dir)
+    filename = Path(filename)
+
+    fexists = True
+    if not filename.exists():
+        mypath = work_dir.joinpath(filename)
+        if not mypath.exists():
+            fexists = False
+    else:
+        mypath = filename
+    return mypath, fexists
+
+
+# ============================================================================
+# Environment Variable Operations
+# ============================================================================
+
+def check_environment_var(env_str: str) -> Path:
+    """
+    Get and validate an environment variable as a Path.
+
+    Args:
+        env_str: Name of the environment variable
+
+    Returns:
+        Path object from the environment variable
+
+    Exits:
+        Exits the program if the environment variable is not set or empty
+    """
+    out_path = os.environ.get(env_str)
+    if out_path:
+        return Path(out_path)
+    else:
+        print(f"Umgebungsvariable {env_str} ist nicht gesetzt oder leer.")
+        exit()
+
+
+# ============================================================================
+# JSON Operations
+# ============================================================================
+
+def to_json(d: Any, pretty: bool = True) -> str:
+    """
+    Convert a Python object to a JSON string.
+
+    Args:
+        d: Object to convert to JSON
+        pretty: If True, format with indentation for readability
+
+    Returns:
+        JSON string representation of the object
+
+    Note:
+        Uses ensure_ascii=False to properly display German umlauts (ä, ö, ü)
+    """
+    return json.dumps(d, indent=2 if pretty else None, ensure_ascii=False, default=str)
+
+
+def load_json(jsonfilename: str) -> dict:
+    """
+    Load JSON data from a file.
+
+    Args:
+        jsonfilename: Path to the JSON file
+
+    Returns:
+        Parsed JSON data as a dictionary
+    """
+    with open(jsonfilename, encoding='utf-8') as fh:
+        return json.load(fh)
+
+
+def write_results(jsn_results: str, out_dir: Path, filename: str) -> None:
+    """
+    Write JSON results to a file.
+
+    Args:
+        jsn_results: JSON string to write
+        out_dir: Output directory path
+        filename: Name of the output file
+    """
+    print("writing results to a json file ...")
+    outfile = Path(out_dir) / filename
+    with open(outfile, 'w', encoding='utf-8') as fh:
+        fh.write(jsn_results)
+    print("done")
+
+
+# ============================================================================
+# DXF File Operations
+# ============================================================================
+
+def dxf_is_binary(dxf_path: Path) -> bool:
+    """
+    Check if a DXF file is in binary format.
+
+    Args:
+        dxf_path: Path to the DXF file
+
+    Returns:
+        True if the file is a binary DXF, False otherwise
+    """
+    with open(dxf_path, 'rb') as f:
+        header = f.read(22)
+        return b'AutoCAD Binary DXF' in header
+
+
+def get_dxf_file(filepath: Path):
+    """
+    Load a DXF file using ezdxf.
+
+    Args:
+        filepath: Path to the DXF file
+
+    Returns:
+        ezdxf Drawing object
+
+    Exits:
+        Exits with code 1 for I/O errors
+        Exits with code 2 for invalid/corrupted DXF files
+    """
+    try:
+        print("reading file ..", end='')
+        doc = ezdxf.filemanagement.readfile(filepath)
+        print("done")
+    except IOError:
+        print("Not a DXF file or a generic I/O error.")
+        sys.exit(1)
+    except DXFStructureError:
+        print("Invalid or corrupted DXF file.")
+        sys.exit(2)
+    return doc
+
+
+# ============================================================================
+# Dictionary Operations
+# ============================================================================
+
+def merge_two_dicts(x: dict, y: dict) -> dict:
+    """
+    Merge two dictionaries, with values from y overwriting those in x.
+
+    Args:
+        x: First dictionary (base)
+        y: Second dictionary (override values)
+
+    Returns:
+        New dictionary with merged values
+    """
+    z = x.copy()
+    z.update(y)
+    return z