"""
SCAFFOLDED MODULE — NOT YET INTEGRATED

This file is intentionally scaffolded.
Structure, interfaces, and intent are defined,
but this module is not yet wired into the active runtime.

⚠️ Do NOT assume runtime execution.
⚠️ Do NOT extend behavior without integration work.

Status: SCAFFOLDED
"""

"""
APE Compiler Optimizer (v1.0.0 Scaffold)

Optimization passes for APE AST and bytecode.

Author: David Van Aelst
Status: Scaffold - implementation pending
"""

from abc import ABC, abstractmethod
from typing import Any, List
from dataclasses import dataclass


@dataclass
class OptimizationResult:
    """Result of an optimization pass"""
    optimized_ast: Any
    changes_made: bool
    description: str


class OptimizationPass(ABC):
    """Base class for optimization passes"""
    
    @abstractmethod
    def optimize(self, ast: Any) -> OptimizationResult:
        """
        Apply optimization to AST.
        
        Args:
            ast: Abstract syntax tree to optimize
        
        Returns:
            OptimizationResult with optimized AST
        """
        pass
    
    @property
    @abstractmethod
    def name(self) -> str:
        """Name of this optimization pass"""
        pass


class ConstantFolding(OptimizationPass):
    """
    Constant folding optimization.
    
    Evaluates constant expressions at compile time.
    
    Examples:
        2 + 3 → 5
        "hello" + " " + "world" → "hello world"
        true and false → false
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    @property
    def name(self) -> str:
        return "Constant Folding"
    
    def optimize(self, ast: Any) -> OptimizationResult:
        """TODO: Implement constant folding"""
        raise NotImplementedError("Constant folding not yet implemented")


class DeadCodeElimination(OptimizationPass):
    """
    Dead code elimination optimization.
    
    Removes unreachable code and unused variables.
    
    Examples:
        if true: ... else: ... → if true: ...
        Unreachable code after return
        Unused variable assignments
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    @property
    def name(self) -> str:
        return "Dead Code Elimination"
    
    def optimize(self, ast: Any) -> OptimizationResult:
        """TODO: Implement dead code elimination"""
        raise NotImplementedError("Dead code elimination not yet implemented")


class CommonSubexpressionElimination(OptimizationPass):
    """
    Common subexpression elimination (CSE).
    
    Identifies and eliminates redundant calculations.
    
    Example:
        a = b * c + d
        e = b * c + f
        
        Optimized:
        temp = b * c
        a = temp + d
        e = temp + f
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    @property
    def name(self) -> str:
        return "Common Subexpression Elimination"
    
    def optimize(self, ast: Any) -> OptimizationResult:
        """TODO: Implement CSE"""
        raise NotImplementedError("CSE not yet implemented")


class LoopUnrolling(OptimizationPass):
    """
    Loop unrolling optimization.
    
    Expands loops with known iteration counts to reduce loop overhead.
    
    Example:
        for i in range(3):
            process(i)
        
        Optimized:
        process(0)
        process(1)
        process(2)
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    @property
    def name(self) -> str:
        return "Loop Unrolling"
    
    def optimize(self, ast: Any) -> OptimizationResult:
        """TODO: Implement loop unrolling"""
        raise NotImplementedError("Loop unrolling not yet implemented")


class TailCallOptimization(OptimizationPass):
    """
    Tail call optimization (TCO).
    
    Converts tail-recursive calls to iteration to prevent stack overflow.
    
    Example:
        task factorial(n, acc):
            if n == 0:
                return acc
            return factorial(n - 1, n * acc)
        
        Optimized to iterative form
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    @property
    def name(self) -> str:
        return "Tail Call Optimization"
    
    def optimize(self, ast: Any) -> OptimizationResult:
        """TODO: Implement TCO"""
        raise NotImplementedError("TCO not yet implemented")


class Optimizer:
    """
    Main optimizer orchestrating multiple optimization passes.
    
    Example:
        optimizer = Optimizer()
        optimizer.add_pass(ConstantFolding())
        optimizer.add_pass(DeadCodeElimination())
        optimized_ast = optimizer.run(ast)
    
    Author: David Van Aelst
    Status: v1.0.0 scaffold - implementation pending
    """
    
    def __init__(self, max_iterations: int = 3):
        self._passes: List[OptimizationPass] = []
        self._max_iterations = max_iterations
    
    def add_pass(self, optimization_pass: OptimizationPass):
        """Add an optimization pass"""
        self._passes.append(optimization_pass)
    
    def run(self, ast: Any) -> Any:
        """
        Run all optimization passes on AST.
        
        TODO: Implement optimization orchestration
        """
        raise NotImplementedError("Optimizer.run() not yet implemented")


__all__ = [
    'OptimizationPass',
    'OptimizationResult',
    'ConstantFolding',
    'DeadCodeElimination',
    'CommonSubexpressionElimination',
    'LoopUnrolling',
    'TailCallOptimization',
    'Optimizer',
]
