from typing import Dict, Optional, Sequence

from ..common import GenericPath
from ..ffi import TaskId
from ..ffi.protocol import ResourceRequest

EnvType = Dict[str, str]


class Task:
    def __init__(
        self,
        task_id: TaskId,
        dependencies: Sequence["Task"] = (),
        priority: int = 0,
        resources: Optional[ResourceRequest] = None,
        env: Optional[EnvType] = None,
        cwd: Optional[GenericPath] = None,
        stdout: Optional[GenericPath] = None,
        stderr: Optional[GenericPath] = None,
        name: Optional[str] = None,
    ):
        assert dependencies is not None
        self.task_id = task_id
        self.dependencies = dependencies
        self.priority = priority
        self.resources = resources
        self.env = env or {}
        self.cwd = str(cwd) if cwd else None
        self.stdout = str(stdout) if stdout else None
        self.stderr = str(stderr) if stdout else None
        self.name = name

    @property
    def label(self) -> str:
        """
        Returns the label of the task.
        If the task has an assigned name, the label is equal to the name.
        Otherwise, the label is the ID of the task converted to a string.
        """
        return self.name if self.name is not None else str(self.task_id)

    def _build(self, client):
        raise NotImplementedError