from __future__ import annotations

from sqlalchemy import select
from sqlalchemy.orm import Session

from app.models.approval import ApprovalRequest


class ApprovalRepository:
    def __init__(self, db: Session) -> None:
        self.db = db

    def add(self, approval: ApprovalRequest) -> ApprovalRequest:
        self.db.add(approval)
        self.db.commit()
        self.db.refresh(approval)
        return approval

    def update(self, approval: ApprovalRequest) -> ApprovalRequest:
        self.db.add(approval)
        self.db.commit()
        self.db.refresh(approval)
        return approval

    def get_by_approval_id(self, approval_id: str) -> ApprovalRequest | None:
        statement = select(ApprovalRequest).where(ApprovalRequest.approval_id == approval_id)
        return self.db.execute(statement).scalar_one_or_none()

    def get_by_task_id(self, task_id: str) -> ApprovalRequest | None:
        statement = select(ApprovalRequest).where(ApprovalRequest.task_id == task_id)
        return self.db.execute(statement).scalar_one_or_none()

    def list_pending(self, approver_user_id: str | None = None) -> list[ApprovalRequest]:
        statement = select(ApprovalRequest).where(ApprovalRequest.approval_status == "PENDING")
        approvals = list(self.db.execute(statement).scalars())
        if approver_user_id is None:
            return approvals
        return [item for item in approvals if approver_user_id in item.approver_user_ids_json]