from typing import List, Optional
from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session
from sqlalchemy.sql import func
from pydantic import BaseModel

from database import get_db
from auth import get_current_active_user
from models import User, SavedSearch

router = APIRouter(prefix="/searches", tags=["Saved Searches"])


class SavedSearchCreate(BaseModel):
    name: str
    query: str
    filters: Optional[dict] = None
    results_count: Optional[int] = 0


class SavedSearchUpdate(BaseModel):
    name: Optional[str] = None
    filters: Optional[dict] = None
    results_count: Optional[int] = None


class SavedSearchResponse(BaseModel):
    id: int
    name: str
    query: str
    filters: Optional[dict]
    results_count: int
    last_used: str

    class Config:
        from_attributes = True


@router.get("/", response_model=List[SavedSearchResponse])
def get_saved_searches(
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Get all saved searches for the current user"""
    searches = db.query(SavedSearch).filter(
        SavedSearch.user_id == current_user.id
    ).order_by(SavedSearch.last_used.desc()).all()

    return [
        SavedSearchResponse(
            id=s.id,
            name=s.name,
            query=s.query,
            filters=s.filters,
            results_count=s.results_count,
            last_used=s.last_used.isoformat() if s.last_used else ""
        )
        for s in searches
    ]


@router.post("/", response_model=SavedSearchResponse, status_code=status.HTTP_201_CREATED)
def create_saved_search(
    search_data: SavedSearchCreate,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Create a new saved search"""
    search = SavedSearch(
        user_id=current_user.id,
        name=search_data.name,
        query=search_data.query,
        filters=search_data.filters,
        results_count=search_data.results_count
    )
    db.add(search)
    db.commit()
    db.refresh(search)

    return SavedSearchResponse(
        id=search.id,
        name=search.name,
        query=search.query,
        filters=search.filters,
        results_count=search.results_count,
        last_used=search.last_used.isoformat() if search.last_used else ""
    )


@router.get("/{search_id}", response_model=SavedSearchResponse)
def get_saved_search(
    search_id: int,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Get a specific saved search"""
    search = db.query(SavedSearch).filter(
        SavedSearch.id == search_id,
        SavedSearch.user_id == current_user.id
    ).first()

    if not search:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Saved search not found"
        )

    return SavedSearchResponse(
        id=search.id,
        name=search.name,
        query=search.query,
        filters=search.filters,
        results_count=search.results_count,
        last_used=search.last_used.isoformat() if search.last_used else ""
    )


@router.put("/{search_id}", response_model=SavedSearchResponse)
def update_saved_search(
    search_id: int,
    search_update: SavedSearchUpdate,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Update a saved search"""
    search = db.query(SavedSearch).filter(
        SavedSearch.id == search_id,
        SavedSearch.user_id == current_user.id
    ).first()

    if not search:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Saved search not found"
        )

    update_data = search_update.model_dump(exclude_unset=True)
    for field, value in update_data.items():
        setattr(search, field, value)

    db.commit()
    db.refresh(search)

    return SavedSearchResponse(
        id=search.id,
        name=search.name,
        query=search.query,
        filters=search.filters,
        results_count=search.results_count,
        last_used=search.last_used.isoformat() if search.last_used else ""
    )


@router.post("/{search_id}/use")
def mark_search_used(
    search_id: int,
    results_count: Optional[int] = None,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Mark a saved search as used (updates last_used timestamp)"""
    search = db.query(SavedSearch).filter(
        SavedSearch.id == search_id,
        SavedSearch.user_id == current_user.id
    ).first()

    if not search:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Saved search not found"
        )

    search.last_used = func.now()
    if results_count is not None:
        search.results_count = results_count

    db.commit()
    return {"message": "Search marked as used"}


@router.delete("/{search_id}")
def delete_saved_search(
    search_id: int,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """Delete a saved search"""
    search = db.query(SavedSearch).filter(
        SavedSearch.id == search_id,
        SavedSearch.user_id == current_user.id
    ).first()

    if not search:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Saved search not found"
        )

    db.delete(search)
    db.commit()
    return {"message": "Saved search deleted"}