"""
SearchSourceConnector routes for CRUD operations:
POST /search-source-connectors/ - Create a new connector
GET /search-source-connectors/ - List all connectors for the current user
GET /search-source-connectors/{connector_id} - Get a specific connector
PUT /search-source-connectors/{connector_id} - Update a specific connector
DELETE /search-source-connectors/{connector_id} - Delete a specific connector
POST /search-source-connectors/{connector_id}/index - Index content from a connector to a search space

Note: Each user can have only one connector of each type (SERPER_API, TAVILY_API, SLACK_CONNECTOR, NOTION_CONNECTOR).
"""
from fastapi import APIRouter, Depends, HTTPException, Query, BackgroundTasks, Body
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.future import select
from sqlalchemy.exc import IntegrityError
from typing import List, Dict, Any
from app.db import get_async_session, User, SearchSourceConnector, SearchSourceConnectorType, SearchSpace, async_session_maker
from app.schemas import SearchSourceConnectorCreate, SearchSourceConnectorUpdate, SearchSourceConnectorRead
from app.users import current_active_user
from app.utils.check_ownership import check_ownership
from pydantic import ValidationError, BaseModel, Field
from app.tasks.connectors_indexing_tasks import index_slack_messages, index_notion_pages, index_github_repos
from app.connectors.github_connector import GitHubConnector
from datetime import datetime, timezone
import logging

# Set up logging
logger = logging.getLogger(__name__)

router = APIRouter()

# --- New Schema for GitHub PAT ---
class GitHubPATRequest(BaseModel):
    github_pat: str = Field(..., description="GitHub Personal Access Token")

# --- New Endpoint to list GitHub Repositories ---
@router.post("/github/repositories/", response_model=List[Dict[str, Any]])
async def list_github_repositories(
    pat_request: GitHubPATRequest,
    user: User = Depends(current_active_user) # Ensure the user is logged in
):
    """
    Fetches a list of repositories accessible by the provided GitHub PAT.
    The PAT is used for this request only and is not stored.
    """
    try:
        # Initialize GitHubConnector with the provided PAT
        github_client = GitHubConnector(token=pat_request.github_pat)
        # Fetch repositories
        repositories = github_client.get_user_repositories()
        return repositories
    except ValueError as e:
        # Handle invalid token error specifically
        logger.error(f"GitHub PAT validation failed for user {user.id}: {str(e)}")
        raise HTTPException(status_code=400, detail=f"Invalid GitHub PAT: {str(e)}")
    except Exception as e:
        logger.error(f"Failed to fetch GitHub repositories for user {user.id}: {str(e)}")
        raise HTTPException(status_code=500, detail="Failed to fetch GitHub repositories.")

@router.post("/search-source-connectors/", response_model=SearchSourceConnectorRead)
async def create_search_source_connector(
    connector: SearchSourceConnectorCreate,
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user)
):
    """
    Create a new search source connector.
    
    Each user can have only one connector of each type (SERPER_API, TAVILY_API, SLACK_CONNECTOR).
    The config must contain the appropriate keys for the connector type.
    """
    try:
        # Check if a connector with the same type already exists for this user
        result = await session.execute(
            select(SearchSourceConnector)
            .filter(
                SearchSourceConnector.user_id == user.id,
                SearchSourceConnector.connector_type == connector.connector_type
            )
        )
        existing_connector = result.scalars().first()
        if existing_connector:
            raise HTTPException(
                status_code=409,
                detail=f"A connector with type {connector.connector_type} already exists. Each user can have only one connector of each type."
            )
        db_connector = SearchSourceConnector(**connector.model_dump(), user_id=user.id)
        session.add(db_connector)
        await session.commit()
        await session.refresh(db_connector)
        return db_connector
    except ValidationError as e:
        await session.rollback()
        raise HTTPException(
            status_code=422,
            detail=f"Validation error: {str(e)}"
        )
    except IntegrityError as e:
        await session.rollback()
        raise HTTPException(
            status_code=409,
            detail=f"Integrity error: A connector with this type already exists. {str(e)}"
        )
    except HTTPException:
        await session.rollback()
        raise
    except Exception as e:
        await session.rollback()
        raise HTTPException(
            status_code=500,
            detail=f"Failed to create search source connector: {str(e)}"
        )

@router.get("/search-source-connectors/", response_model=List[SearchSourceConnectorRead])
async def read_search_source_connectors(
    skip: int = 0,
    limit: int = 100,
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user)
):
    """List all search source connectors for the current user."""
    try:
        result = await session.execute(
            select(SearchSourceConnector)
            .filter(SearchSourceConnector.user_id == user.id)
            .offset(skip)
            .limit(limit)
        )
        return result.scalars().all()
    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=f"Failed to fetch search source connectors: {str(e)}"
        )

@router.get("/search-source-connectors/{connector_id}", response_model=SearchSourceConnectorRead)
async def read_search_source_connector(
    connector_id: int,
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user)
):
    """Get a specific search source connector by ID."""
    try:
        return await check_ownership(session, SearchSourceConnector, connector_id, user)
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=f"Failed to fetch search source connector: {str(e)}"
        )

@router.put("/search-source-connectors/{connector_id}", response_model=SearchSourceConnectorRead)
async def update_search_source_connector(
    connector_id: int,
    connector_update: SearchSourceConnectorUpdate,
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user)
):
    """
    Update a search source connector.
    
    Each user can have only one connector of each type (SERPER_API, TAVILY_API, SLACK_CONNECTOR).
    The config must contain the appropriate keys for the connector type.
    """
    try:
        db_connector = await check_ownership(session, SearchSourceConnector, connector_id, user)
        
        # If connector type is being changed, check if one of that type already exists
        if connector_update.connector_type != db_connector.connector_type:
            result = await session.execute(
                select(SearchSourceConnector)
                .filter(
                    SearchSourceConnector.user_id == user.id,
                    SearchSourceConnector.connector_type == connector_update.connector_type,
                    SearchSourceConnector.id != connector_id
                )
            )
            existing_connector = result.scalars().first()
            
            if existing_connector:
                raise HTTPException(
                    status_code=409,
                    detail=f"A connector with type {connector_update.connector_type} already exists. Each user can have only one connector of each type."
                )
        
        update_data = connector_update.model_dump(exclude_unset=True)
        for key, value in update_data.items():
            setattr(db_connector, key, value)
        await session.commit()
        await session.refresh(db_connector)
        return db_connector
    except ValidationError as e:
        await session.rollback()
        raise HTTPException(
            status_code=422,
            detail=f"Validation error: {str(e)}"
        )
    except IntegrityError as e:
        await session.rollback()
        raise HTTPException(
            status_code=409,
            detail=f"Integrity error: A connector with this type already exists. {str(e)}"
        )
    except HTTPException:
        await session.rollback()
        raise
    except Exception as e:
        await session.rollback()
        raise HTTPException(
            status_code=500,
            detail=f"Failed to update search source connector: {str(e)}"
        )

@router.delete("/search-source-connectors/{connector_id}", response_model=dict)
async def delete_search_source_connector(
    connector_id: int,
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user)
):
    """Delete a search source connector."""
    try:
        db_connector = await check_ownership(session, SearchSourceConnector, connector_id, user)
        await session.delete(db_connector)
        await session.commit()
        return {"message": "Search source connector deleted successfully"}
    except HTTPException:
        raise
    except Exception as e:
        await session.rollback()
        raise HTTPException(
            status_code=500,
            detail=f"Failed to delete search source connector: {str(e)}"
        )

@router.post("/search-source-connectors/{connector_id}/index", response_model=Dict[str, Any])
async def index_connector_content(
    connector_id: int,
    search_space_id: int = Query(..., description="ID of the search space to store indexed content"),
    session: AsyncSession = Depends(get_async_session),
    user: User = Depends(current_active_user),
    background_tasks: BackgroundTasks = None
):
    """
    Index content from a connector to a search space.
    
    Currently supports:
    - SLACK_CONNECTOR: Indexes messages from all accessible Slack channels since the last indexing
      (or the last 365 days if never indexed before)
    - NOTION_CONNECTOR: Indexes pages from all accessible Notion pages since the last indexing
      (or the last 365 days if never indexed before)
    
    Args:
        connector_id: ID of the connector to use
        search_space_id: ID of the search space to store indexed content
        background_tasks: FastAPI background tasks
    
    Returns:
        Dictionary with indexing status
    """
    try:
        # Check if the connector belongs to the user
        connector = await check_ownership(session, SearchSourceConnector, connector_id, user)
        
        # Check if the search space belongs to the user
        search_space = await check_ownership(session, SearchSpace, search_space_id, user)
        
        # Handle different connector types
        response_message = ""
        indexing_from = None
        indexing_to = None
        today_str = datetime.now().strftime("%Y-%m-%d")

        if connector.connector_type == SearchSourceConnectorType.SLACK_CONNECTOR:
            # Determine the time range that will be indexed
            if not connector.last_indexed_at:
                start_date = "365 days ago" # Or perhaps set a specific date if needed
            else:
                # Check if last_indexed_at is today
                today = datetime.now().date()
                if connector.last_indexed_at.date() == today:
                    # If last indexed today, go back 1 day to ensure we don't miss anything
                    start_date = (today - datetime.timedelta(days=1)).strftime("%Y-%m-%d")
                else:
                    start_date = connector.last_indexed_at.strftime("%Y-%m-%d")
            
            indexing_from = start_date
            indexing_to = today_str
            
            # Run indexing in background
            logger.info(f"Triggering Slack indexing for connector {connector_id} into search space {search_space_id}")
            background_tasks.add_task(run_slack_indexing_with_new_session, connector_id, search_space_id)
            response_message = "Slack indexing started in the background."

        elif connector.connector_type == SearchSourceConnectorType.NOTION_CONNECTOR:
            # Determine the time range that will be indexed
            if not connector.last_indexed_at:
                start_date = "365 days ago" # Or perhaps set a specific date
            else:
                # Check if last_indexed_at is today
                today = datetime.now().date()
                if connector.last_indexed_at.date() == today:
                    # If last indexed today, go back 1 day to ensure we don't miss anything
                    start_date = (today - datetime.timedelta(days=1)).strftime("%Y-%m-%d")
                else:
                    start_date = connector.last_indexed_at.strftime("%Y-%m-%d")
            
            indexing_from = start_date
            indexing_to = today_str

            # Run indexing in background
            logger.info(f"Triggering Notion indexing for connector {connector_id} into search space {search_space_id}")
            background_tasks.add_task(run_notion_indexing_with_new_session, connector_id, search_space_id)
            response_message = "Notion indexing started in the background."
            
        elif connector.connector_type == SearchSourceConnectorType.GITHUB_CONNECTOR:
            # GitHub connector likely indexes everything relevant, or uses internal logic
            # Setting indexing_from to None and indexing_to to today
            indexing_from = None 
            indexing_to = today_str

            # Run indexing in background
            logger.info(f"Triggering GitHub indexing for connector {connector_id} into search space {search_space_id}")
            background_tasks.add_task(run_github_indexing_with_new_session, connector_id, search_space_id)
            response_message = "GitHub indexing started in the background."

        else:
            raise HTTPException(
                status_code=400,
                detail=f"Indexing not supported for connector type: {connector.connector_type}"
            )

        return {
            "message": response_message, 
            "connector_id": connector_id, 
            "search_space_id": search_space_id,
            "indexing_from": indexing_from,
            "indexing_to": indexing_to
        }
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"Failed to initiate indexing for connector {connector_id}: {e}", exc_info=True)
        raise HTTPException(
            status_code=500,
            detail=f"Failed to initiate indexing: {str(e)}"
        )
        
async def update_connector_last_indexed(
    session: AsyncSession,
    connector_id: int
):
    """
    Update the last_indexed_at timestamp for a connector.
    
    Args:
        session: Database session
        connector_id: ID of the connector to update
    """
    try:
        result = await session.execute(
            select(SearchSourceConnector)
            .filter(SearchSourceConnector.id == connector_id)
        )
        connector = result.scalars().first()
        
        if connector:
            connector.last_indexed_at = datetime.now()
            await session.commit()
            logger.info(f"Updated last_indexed_at for connector {connector_id}")
    except Exception as e:
        logger.error(f"Failed to update last_indexed_at for connector {connector_id}: {str(e)}")
        await session.rollback()

async def run_slack_indexing_with_new_session(
    connector_id: int,
    search_space_id: int
):
    """
    Create a new session and run the Slack indexing task.
    This prevents session leaks by creating a dedicated session for the background task.
    """
    async with async_session_maker() as session:
        await run_slack_indexing(session, connector_id, search_space_id)

async def run_slack_indexing(
    session: AsyncSession,
    connector_id: int,
    search_space_id: int
):
    """
    Background task to run Slack indexing.
    
    Args:
        session: Database session
        connector_id: ID of the Slack connector
        search_space_id: ID of the search space
    """
    try:
        # Index Slack messages without updating last_indexed_at (we'll do it separately)
        documents_processed, error_or_warning = await index_slack_messages(
            session=session,
            connector_id=connector_id,
            search_space_id=search_space_id,
            update_last_indexed=False  # Don't update timestamp in the indexing function
        )
        
        # Only update last_indexed_at if indexing was successful (either new docs or updated docs)
        if documents_processed > 0:
            await update_connector_last_indexed(session, connector_id)
            logger.info(f"Slack indexing completed successfully: {documents_processed} documents processed")
        else:
            logger.error(f"Slack indexing failed or no documents processed: {error_or_warning}")
    except Exception as e:
        logger.error(f"Error in background Slack indexing task: {str(e)}")

async def run_notion_indexing_with_new_session(
    connector_id: int,
    search_space_id: int
):
    """
    Create a new session and run the Notion indexing task.
    This prevents session leaks by creating a dedicated session for the background task.
    """
    async with async_session_maker() as session:
        await run_notion_indexing(session, connector_id, search_space_id)

async def run_notion_indexing(
    session: AsyncSession,
    connector_id: int,
    search_space_id: int
):
    """
    Background task to run Notion indexing.
    
    Args:
        session: Database session
        connector_id: ID of the Notion connector
        search_space_id: ID of the search space
    """
    try:
        # Index Notion pages without updating last_indexed_at (we'll do it separately)
        documents_processed, error_or_warning = await index_notion_pages(
            session=session,
            connector_id=connector_id,
            search_space_id=search_space_id,
            update_last_indexed=False  # Don't update timestamp in the indexing function
        )
        
        # Only update last_indexed_at if indexing was successful (either new docs or updated docs)
        if documents_processed > 0:
            await update_connector_last_indexed(session, connector_id)
            logger.info(f"Notion indexing completed successfully: {documents_processed} documents processed")
        else:
            logger.error(f"Notion indexing failed or no documents processed: {error_or_warning}")
    except Exception as e:
        logger.error(f"Error in background Notion indexing task: {str(e)}")

# Add new helper functions for GitHub indexing
async def run_github_indexing_with_new_session(
    connector_id: int,
    search_space_id: int
):
    """Wrapper to run GitHub indexing with its own database session."""
    logger.info(f"Background task started: Indexing GitHub connector {connector_id} into space {search_space_id}")
    async with async_session_maker() as session:
        await run_github_indexing(session, connector_id, search_space_id)
    logger.info(f"Background task finished: Indexing GitHub connector {connector_id}")

async def run_github_indexing(
    session: AsyncSession,
    connector_id: int,
    search_space_id: int
):
    """Runs the GitHub indexing task and updates the timestamp."""
    try:
        indexed_count, error_message = await index_github_repos(
            session, connector_id, search_space_id, update_last_indexed=False
        )
        if error_message:
            logger.error(f"GitHub indexing failed for connector {connector_id}: {error_message}")
            # Optionally update status in DB to indicate failure
        else:
            logger.info(f"GitHub indexing successful for connector {connector_id}. Indexed {indexed_count} documents.")
            # Update the last indexed timestamp only on success
            await update_connector_last_indexed(session, connector_id)
            await session.commit() # Commit timestamp update
    except Exception as e:
        await session.rollback()
        logger.error(f"Critical error in run_github_indexing for connector {connector_id}: {e}", exc_info=True)
        # Optionally update status in DB to indicate failure