from playwright.async_api import Page

from skyvern.exceptions import StepTerminationError
from skyvern.forge import app
from skyvern.forge.async_operations import AsyncOperation
from skyvern.forge.sdk.models import Organization, Step, StepStatus
from skyvern.forge.sdk.schemas.tasks import Task, TaskStatus


class AgentFunction:
    async def validate_step_execution(
        self,
        task: Task,
        step: Step,
    ) -> None:
        """
        Checks if the step can be executed.
        :return: A tuple of whether the step can be executed and a list of reasons why it can't be executed.
        """
        reasons = []
        # can't execute if task status is not running
        has_valid_task_status = task.status == TaskStatus.running
        if not has_valid_task_status:
            reasons.append(f"invalid_task_status:{task.status}")
        # can't execute if the step is already running or completed
        has_valid_step_status = step.status in [StepStatus.created, StepStatus.failed]
        if not has_valid_step_status:
            reasons.append(f"invalid_step_status:{step.status}")
        # can't execute if the task has another step that is running
        steps = await app.DATABASE.get_task_steps(task_id=task.task_id, organization_id=task.organization_id)
        has_no_running_steps = not any(step.status == StepStatus.running for step in steps)
        if not has_no_running_steps:
            reasons.append(f"another_step_is_running_for_task:{task.task_id}")

        can_execute = has_valid_task_status and has_valid_step_status and has_no_running_steps
        if not can_execute:
            raise StepTerminationError(step_id=step.step_id, reason="Cannot execute step. Reasons: {reasons}")

    def generate_async_operations(
        self,
        organization: Organization,
        task: Task,
        page: Page,
    ) -> list[AsyncOperation]:
        return []