"""Executor — dispatches plan steps to tools, never raises."""
from __future__ import annotations

from core.state import PlanStep, StepResult, StepStatus
from runtime.tool_registry import ToolRegistry


class Executor:
    """Executes a PlanStep by delegating to the appropriate tool handler."""

    def __init__(self, registry: ToolRegistry) -> None:
        self._registry = registry

    def execute(self, step: PlanStep) -> StepResult:
        """
        Execute a step. All exceptions are caught and returned as
        a FAILED StepResult — the caller never needs to handle exceptions.
        """
        handler = self._registry.get(step.kind)
        if handler is None:
            return StepResult(
                step_id=step.step_id,
                status=StepStatus.FAILED,
                error=f"No handler registered for step kind '{step.kind}'",
            )
        try:
            return handler(step)
        except Exception as exc:  # noqa: BLE001
            return StepResult(
                step_id=step.step_id,
                status=StepStatus.FAILED,
                error=f"{type(exc).__name__}: {exc}",
            )