"""
CSL-Core Factory
================
The manufacturing plant for ChimeraGuard instances.
This module handles the heavy lifting (Parsing & Compilation)
so the Runtime can stay lightweight.
"""
import os
from typing import Optional, Union
from pathlib import Path
from .runtime import ChimeraGuard, RuntimeConfig
from .language.parser import parse_csl_file, parse_csl
from .language.compiler import CSLCompiler
def load_guard(
policy_path: Union[str, Path],
config: Optional[RuntimeConfig] = None
) -> ChimeraGuard:
"""
Factory Method: Loads a .csl file from disk, compiles it, and returns a Guard.
Args:
policy_path: Path to the .csl file (str or Path object).
Supports relative paths and user expansion (~/).
config: Optional runtime configuration override.
Returns:
A ready-to-use ChimeraGuard instance.
Raises:
FileNotFoundError: If the policy file does not exist.
CompilationError: If the CSL syntax or logic is invalid.
"""
# 1. Path Normalization & Validation
# - expanduser: Handles "~/policies/..."
# - resolve: Converts relative paths to absolute, fixing ".." confusion
path_obj = Path(policy_path).expanduser().resolve()
if not path_obj.exists():
raise FileNotFoundError(
f"❌ CSL Policy file not found at: '{path_obj}'\n"
f" (Current working directory: '{os.getcwd()}')"
)
# 2. Parse (Read file -> AST)
# We pass the absolute path string to the parser
constitution_ast = parse_csl_file(str(path_obj))
# 3. Compile (AST -> Logic Model)
# Note: Creating a fresh compiler instance is cheap for now.
# If compilation gets heavy, we can add LRU caching here later.
compiler = CSLCompiler()
compiled_policy = compiler.compile(constitution_ast)
# 4. Construct (Logic Model -> Runtime Guard)
return ChimeraGuard(compiled_policy, config)
def create_guard_from_string(
policy_content: str,
config: Optional[RuntimeConfig] = None
) -> ChimeraGuard:
"""
Factory Method: Creates a Guard directly from a CSL code string.
Useful for dynamic policies, unit testing, or REPL usage.
Args:
policy_content: The raw CSL code as a string.
config: Optional runtime configuration override.
"""
# 1. Parse String
ast = parse_csl(policy_content)
# 2. Compile
compiler = CSLCompiler()
compiled = compiler.compile(ast)
# 3. Construct
return ChimeraGuard(compiled, config)
