import logging

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

from app.core.database import get_db
from app.dependencies.auth import get_current_active_user
from app.models.order import Order, OrderStatus
from app.models.product import Product
from app.models.review import Review
from app.models.user import User, UserRole
from app.schemas.review import (
    Review as ReviewSchema,
)
from app.schemas.review import (
    ReviewCreate,
    ReviewUpdate,
)

router = APIRouter()
logger = logging.getLogger(__name__)

@router.get("/", response_model=list[ReviewSchema])
async def get_reviews(
    product_id: str | None = None,
    user_id: str | None = None,
    approved_only: bool = True,
    skip: int = 0,
    limit: int = 100,
    db: Session = Depends(get_db),
):
    """
    Get reviews.
    Filter by product_id or user_id.
    Regular users can only see approved reviews for products.
    """
    query = db.query(Review)

    # Filter by product ID if provided
    if product_id:
        query = query.filter(Review.product_id == product_id)

    # Filter by user ID if provided
    if user_id:
        query = query.filter(Review.user_id == user_id)

    # Filter by approved status
    if approved_only:
        query = query.filter(Review.is_approved == True)

    # Apply pagination and order by newest first
    reviews = query.order_by(desc(Review.created_at)).offset(skip).limit(limit).all()

    # Enhance reviews with user and product names
    for review in reviews:
        # Add user name if available
        if review.user and review.user.first_name:
            if review.user.last_name:
                review.user_name = f"{review.user.first_name} {review.user.last_name}"
            else:
                review.user_name = review.user.first_name
        else:
            review.user_name = "Anonymous"

        # Add product name if available
        if review.product:
            review.product_name = review.product.name

    return reviews

@router.get("/{review_id}", response_model=ReviewSchema)
async def get_review(
    review_id: str,
    db: Session = Depends(get_db),
):
    """
    Get a specific review by ID.
    """
    review = db.query(Review).filter(Review.id == review_id).first()
    if not review:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Review not found"
        )

    # Add user name if available
    if review.user and review.user.first_name:
        if review.user.last_name:
            review.user_name = f"{review.user.first_name} {review.user.last_name}"
        else:
            review.user_name = review.user.first_name
    else:
        review.user_name = "Anonymous"

    # Add product name if available
    if review.product:
        review.product_name = review.product.name

    return review

@router.post("/", response_model=ReviewSchema)
async def create_review(
    review_in: ReviewCreate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    """
    Create a new review for a product.
    User must have purchased the product to leave a verified review.
    """
    # Check if product exists
    product = db.query(Product).filter(Product.id == review_in.product_id).first()
    if not product:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Product not found"
        )

    # Check if user has already reviewed this product
    existing_review = db.query(Review).filter(
        Review.product_id == review_in.product_id,
        Review.user_id == current_user.id
    ).first()

    if existing_review:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="You have already reviewed this product"
        )

    # Check if the user has purchased the product for verified review status
    is_verified_purchase = False

    # Query completed orders
    completed_orders = db.query(Order).filter(
        Order.user_id == current_user.id,
        Order.status.in_([OrderStatus.DELIVERED, OrderStatus.COMPLETED])
    ).all()

    # Check if any of these orders contain the product
    for order in completed_orders:
        for item in order.items:
            if item.product_id == review_in.product_id:
                is_verified_purchase = True
                break
        if is_verified_purchase:
            break

    # Admin reviews are always approved, regular user reviews may need approval
    is_approved = True if current_user.role == UserRole.ADMIN else True  # Auto-approve for now

    # Create the review
    db_review = Review(
        product_id=review_in.product_id,
        user_id=current_user.id,
        rating=review_in.rating,
        title=review_in.title,
        comment=review_in.comment,
        is_verified_purchase=is_verified_purchase,
        is_approved=is_approved
    )

    db.add(db_review)
    db.commit()
    db.refresh(db_review)

    # Add user name and product name for the response
    if current_user.first_name:
        if current_user.last_name:
            db_review.user_name = f"{current_user.first_name} {current_user.last_name}"
        else:
            db_review.user_name = current_user.first_name
    else:
        db_review.user_name = "Anonymous"

    db_review.product_name = product.name

    logger.info(f"Review created: ID {db_review.id} for product {product.name}")
    return db_review

@router.put("/{review_id}", response_model=ReviewSchema)
async def update_review(
    review_id: str,
    review_in: ReviewUpdate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    """
    Update a review.
    Users can only update their own reviews.
    Admins can update any review.
    """
    review = db.query(Review).filter(Review.id == review_id).first()
    if not review:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Review not found"
        )

    # Check permissions
    is_admin = current_user.role == UserRole.ADMIN
    is_owner = review.user_id == current_user.id

    if not is_admin and not is_owner:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions to update this review"
        )

    # Regular users cannot update approval status
    update_data = review_in.dict(exclude_unset=True)
    if not is_admin and "is_approved" in update_data:
        del update_data["is_approved"]

    # Update review attributes
    for key, value in update_data.items():
        setattr(review, key, value)

    db.commit()
    db.refresh(review)

    # Add user name and product name for the response
    if review.user and review.user.first_name:
        if review.user.last_name:
            review.user_name = f"{review.user.first_name} {review.user.last_name}"
        else:
            review.user_name = review.user.first_name
    else:
        review.user_name = "Anonymous"

    if review.product:
        review.product_name = review.product.name

    logger.info(f"Review updated: ID {review.id}")
    return review

@router.delete("/{review_id}", response_model=dict)
async def delete_review(
    review_id: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    """
    Delete a review.
    Users can only delete their own reviews.
    Admins can delete any review.
    """
    review = db.query(Review).filter(Review.id == review_id).first()
    if not review:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Review not found"
        )

    # Check permissions
    is_admin = current_user.role == UserRole.ADMIN
    is_owner = review.user_id == current_user.id

    if not is_admin and not is_owner:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions to delete this review"
        )

    db.delete(review)
    db.commit()

    logger.info(f"Review deleted: ID {review.id}")
    return {"message": "Review successfully deleted"}