from __future__ import annotations

from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session

from app.core.dependencies import get_current_user
from app.database.session import get_db
from app.models.user import User
from app.models.workspace import Workspace
from app.repositories.rule_repository import RuleRepository
from app.schemas.rule import RuleCreate, RuleResponse, RuleUpdate


router = APIRouter(
    prefix="/rules",
    tags=["Rules"],
)


def _verify_workspace_access(
    db: Session,
    workspace_id: UUID,
    user_id: UUID,
) -> Workspace:
    workspace = (
        db.query(Workspace)
        .filter(
            Workspace.id == workspace_id,
            Workspace.created_by == user_id,
        )
        .first()
    )
    if workspace is None:
        raise HTTPException(
            status_code=403,
            detail="You do not have access to this workspace.",
        )
    return workspace


@router.get("", response_model=list[RuleResponse])
def list_rules(
    workspace_id: UUID,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    _verify_workspace_access(db, workspace_id, current_user.id)
    repo = RuleRepository(db)
    rules = repo.list_by_workspace(workspace_id)
    return [RuleResponse.from_rule(r) for r in rules]


@router.post("", response_model=RuleResponse, status_code=201)
def create_rule(
    workspace_id: UUID,
    payload: RuleCreate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    _verify_workspace_access(db, workspace_id, current_user.id)
    repo = RuleRepository(db)

    # Merge operator into configuration for storage
    configuration = {**payload.configuration, "operator": payload.operator}

    rule = repo.create(
        workspace_id=workspace_id,
        name=payload.name,
        description=payload.description,
        rule_type=payload.rule_type,
        configuration=configuration,
        enabled=payload.enabled,
    )
    return RuleResponse.from_rule(rule)


@router.get("/{rule_id}", response_model=RuleResponse)
def get_rule(
    rule_id: UUID,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    repo = RuleRepository(db)
    rule = repo.get(rule_id)
    if rule is None:
        raise HTTPException(status_code=404, detail="Rule not found.")
    _verify_workspace_access(db, rule.workspace_id, current_user.id)
    return RuleResponse.from_rule(rule)


@router.patch("/{rule_id}", response_model=RuleResponse)
def update_rule(
    rule_id: UUID,
    payload: RuleUpdate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    repo = RuleRepository(db)
    rule = repo.get(rule_id)
    if rule is None:
        raise HTTPException(status_code=404, detail="Rule not found.")
    _verify_workspace_access(db, rule.workspace_id, current_user.id)

    update_kwargs = {}
    if payload.name is not None:
        update_kwargs["name"] = payload.name
    if payload.description is not None:
        update_kwargs["description"] = payload.description
    if payload.rule_type is not None:
        update_kwargs["rule_type"] = payload.rule_type
    if payload.enabled is not None:
        update_kwargs["enabled"] = payload.enabled

    # Handle operator/configuration updates
    if payload.operator is not None or payload.configuration is not None:
        current_config = dict(rule.configuration or {})
        if payload.configuration is not None:
            current_config.update(payload.configuration)
        if payload.operator is not None:
            current_config["operator"] = payload.operator
        update_kwargs["configuration"] = current_config

    if update_kwargs:
        rule = repo.update(rule, **update_kwargs)

    return RuleResponse.from_rule(rule)


@router.post("/{rule_id}/enable", response_model=RuleResponse)
def enable_rule(
    rule_id: UUID,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    repo = RuleRepository(db)
    rule = repo.get(rule_id)
    if rule is None:
        raise HTTPException(status_code=404, detail="Rule not found.")
    _verify_workspace_access(db, rule.workspace_id, current_user.id)
    rule = repo.update(rule, enabled=True)
    return RuleResponse.from_rule(rule)


@router.post("/{rule_id}/disable", response_model=RuleResponse)
def disable_rule(
    rule_id: UUID,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    repo = RuleRepository(db)
    rule = repo.get(rule_id)
    if rule is None:
        raise HTTPException(status_code=404, detail="Rule not found.")
    _verify_workspace_access(db, rule.workspace_id, current_user.id)
    rule = repo.update(rule, enabled=False)
    return RuleResponse.from_rule(rule)


@router.delete("/{rule_id}", status_code=204)
def delete_rule(
    rule_id: UUID,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    repo = RuleRepository(db)
    rule = repo.get(rule_id)
    if rule is None:
        raise HTTPException(status_code=404, detail="Rule not found.")
    _verify_workspace_access(db, rule.workspace_id, current_user.id)
    repo.delete(rule)