from typing import List, Optional
from pydantic import BaseModel
from fastapi import APIRouter, Depends, HTTPException, status, Request, Query
from fastapi.responses import StreamingResponse
from fastapi.concurrency import run_in_threadpool
import logging
import io
import zipfile
from urllib.parse import quote

from sqlalchemy.orm import Session
from open_webui.internal.db import get_session
from open_webui.models.groups import Groups
from open_webui.models.knowledge import (
    KnowledgeFileListResponse,
    Knowledges,
    KnowledgeForm,
    KnowledgeResponse,
    KnowledgeUserResponse,
)
from open_webui.models.files import Files, FileModel, FileMetadataResponse
from open_webui.retrieval.vector.factory import VECTOR_DB_CLIENT
from open_webui.routers.retrieval import (
    process_file,
    ProcessFileForm,
    process_files_batch,
    BatchProcessFilesForm,
)
from open_webui.storage.provider import Storage

from open_webui.constants import ERROR_MESSAGES
from open_webui.utils.auth import get_verified_user, get_admin_user
from open_webui.utils.access_control import has_permission, filter_allowed_access_grants
from open_webui.models.access_grants import AccessGrants


from open_webui.config import BYPASS_ADMIN_ACCESS_CONTROL
from open_webui.models.models import Models, ModelForm

log = logging.getLogger(__name__)

router = APIRouter()

############################
# getKnowledgeBases
############################

PAGE_ITEM_COUNT = 30

############################
# Knowledge Base Embedding
############################

# Knowledge that sits unread serves no one. Let what is
# stored here find the ones who need it.
KNOWLEDGE_BASES_COLLECTION = 'knowledge-bases'


async def embed_knowledge_base_metadata(
    request: Request,
    knowledge_base_id: str,
    name: str,
    description: str,
) -> bool:
    """Generate and store embedding for knowledge base."""
    try:
        content = f'{name}\n\n{description}' if description else name
        embedding = await request.app.state.EMBEDDING_FUNCTION(content)
        VECTOR_DB_CLIENT.upsert(
            collection_name=KNOWLEDGE_BASES_COLLECTION,
            items=[
                {
                    'id': knowledge_base_id,
                    'text': content,
                    'vector': embedding,
                    'metadata': {
                        'knowledge_base_id': knowledge_base_id,
                    },
                }
            ],
        )
        return True
    except Exception as e:
        log.error(f'Failed to embed knowledge base {knowledge_base_id}: {e}')
        return False


def remove_knowledge_base_metadata_embedding(knowledge_base_id: str) -> bool:
    """Remove knowledge base embedding."""
    try:
        VECTOR_DB_CLIENT.delete(
            collection_name=KNOWLEDGE_BASES_COLLECTION,
            ids=[knowledge_base_id],
        )
        return True
    except Exception as e:
        log.debug(f'Failed to remove embedding for {knowledge_base_id}: {e}')
        return False


class KnowledgeAccessResponse(KnowledgeUserResponse):
    write_access: Optional[bool] = False


class KnowledgeAccessListResponse(BaseModel):
    items: list[KnowledgeAccessResponse]
    total: int


@router.get('/', response_model=KnowledgeAccessListResponse)
async def get_knowledge_bases(
    page: Optional[int] = 1,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    page = max(page, 1)
    limit = PAGE_ITEM_COUNT
    skip = (page - 1) * limit

    filter = {}
    groups = Groups.get_groups_by_member_id(user.id, db=db)
    user_group_ids = {group.id for group in groups}

    if not user.role == 'admin' or not BYPASS_ADMIN_ACCESS_CONTROL:
        if groups:
            filter['group_ids'] = [group.id for group in groups]

        filter['user_id'] = user.id

    result = Knowledges.search_knowledge_bases(user.id, filter=filter, skip=skip, limit=limit, db=db)

    # Batch-fetch writable knowledge IDs in a single query instead of N has_access calls
    knowledge_base_ids = [knowledge_base.id for knowledge_base in result.items]
    writable_knowledge_base_ids = AccessGrants.get_accessible_resource_ids(
        user_id=user.id,
        resource_type='knowledge',
        resource_ids=knowledge_base_ids,
        permission='write',
        user_group_ids=user_group_ids,
        db=db,
    )

    return KnowledgeAccessListResponse(
        items=[
            KnowledgeAccessResponse(
                **knowledge_base.model_dump(),
                write_access=(
                    user.id == knowledge_base.user_id
                    or (user.role == 'admin' and BYPASS_ADMIN_ACCESS_CONTROL)
                    or knowledge_base.id in writable_knowledge_base_ids
                ),
            )
            for knowledge_base in result.items
        ],
        total=result.total,
    )


@router.get('/search', response_model=KnowledgeAccessListResponse)
async def search_knowledge_bases(
    query: Optional[str] = None,
    view_option: Optional[str] = None,
    page: Optional[int] = 1,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    page = max(page, 1)
    limit = PAGE_ITEM_COUNT
    skip = (page - 1) * limit

    filter = {}
    if query:
        filter['query'] = query
    if view_option:
        filter['view_option'] = view_option

    groups = Groups.get_groups_by_member_id(user.id, db=db)
    user_group_ids = {group.id for group in groups}

    if not user.role == 'admin' or not BYPASS_ADMIN_ACCESS_CONTROL:
        if groups:
            filter['group_ids'] = [group.id for group in groups]

        filter['user_id'] = user.id

    result = Knowledges.search_knowledge_bases(user.id, filter=filter, skip=skip, limit=limit, db=db)

    # Batch-fetch writable knowledge IDs in a single query instead of N has_access calls
    knowledge_base_ids = [knowledge_base.id for knowledge_base in result.items]
    writable_knowledge_base_ids = AccessGrants.get_accessible_resource_ids(
        user_id=user.id,
        resource_type='knowledge',
        resource_ids=knowledge_base_ids,
        permission='write',
        user_group_ids=user_group_ids,
        db=db,
    )

    return KnowledgeAccessListResponse(
        items=[
            KnowledgeAccessResponse(
                **knowledge_base.model_dump(),
                write_access=(
                    user.id == knowledge_base.user_id
                    or (user.role == 'admin' and BYPASS_ADMIN_ACCESS_CONTROL)
                    or knowledge_base.id in writable_knowledge_base_ids
                ),
            )
            for knowledge_base in result.items
        ],
        total=result.total,
    )


@router.get('/search/files', response_model=KnowledgeFileListResponse)
async def search_knowledge_files(
    query: Optional[str] = None,
    page: Optional[int] = 1,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    page = max(page, 1)
    limit = PAGE_ITEM_COUNT
    skip = (page - 1) * limit

    filter = {}
    if query:
        filter['query'] = query

    groups = Groups.get_groups_by_member_id(user.id, db=db)
    if groups:
        filter['group_ids'] = [group.id for group in groups]

    filter['user_id'] = user.id

    return Knowledges.search_knowledge_files(filter=filter, skip=skip, limit=limit, db=db)


############################
# CreateNewKnowledge
############################


@router.post('/create', response_model=Optional[KnowledgeResponse])
async def create_new_knowledge(
    request: Request,
    form_data: KnowledgeForm,
    user=Depends(get_verified_user),
):
    # NOTE: We intentionally do NOT use Depends(get_session) here.
    # Database operations (has_permission, filter_allowed_access_grants, insert_new_knowledge) manage their own sessions.
    # This prevents holding a connection during embed_knowledge_base_metadata()
    # which makes external embedding API calls (1-5+ seconds).
    if user.role != 'admin' and not has_permission(
        user.id, 'workspace.knowledge', request.app.state.config.USER_PERMISSIONS
    ):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail=ERROR_MESSAGES.UNAUTHORIZED,
        )

    form_data.access_grants = filter_allowed_access_grants(
        request.app.state.config.USER_PERMISSIONS,
        user.id,
        user.role,
        form_data.access_grants,
        'sharing.public_knowledge',
    )

    knowledge = Knowledges.insert_new_knowledge(user.id, form_data)

    if knowledge:
        # Embed knowledge base for semantic search
        await embed_knowledge_base_metadata(
            request,
            knowledge.id,
            knowledge.name,
            knowledge.description,
        )
        return knowledge
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.FILE_EXISTS,
        )


############################
# ReindexKnowledgeFiles
############################


@router.post('/reindex', response_model=bool)
async def reindex_knowledge_files(
    request: Request,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    if user.role != 'admin':
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail=ERROR_MESSAGES.UNAUTHORIZED,
        )

    knowledge_bases = Knowledges.get_knowledge_bases(db=db)

    log.info(f'Starting reindexing for {len(knowledge_bases)} knowledge bases')

    for knowledge_base in knowledge_bases:
        try:
            files = Knowledges.get_files_by_id(knowledge_base.id, db=db)
            try:
                if VECTOR_DB_CLIENT.has_collection(collection_name=knowledge_base.id):
                    VECTOR_DB_CLIENT.delete_collection(collection_name=knowledge_base.id)
            except Exception as e:
                log.error(f'Error deleting collection {knowledge_base.id}: {str(e)}')
                continue  # Skip, don't raise

            failed_files = []
            for file in files:
                try:
                    await run_in_threadpool(
                        process_file,
                        request,
                        ProcessFileForm(file_id=file.id, collection_name=knowledge_base.id),
                        user=user,
                        db=db,
                    )
                except Exception as e:
                    log.error(f'Error processing file {file.filename} (ID: {file.id}): {str(e)}')
                    failed_files.append({'file_id': file.id, 'error': str(e)})
                    continue

        except Exception as e:
            log.error(f'Error processing knowledge base {knowledge_base.id}: {str(e)}')
            # Don't raise, just continue
            continue

        if failed_files:
            log.warning(f'Failed to process {len(failed_files)} files in knowledge base {knowledge_base.id}')
            for failed in failed_files:
                log.warning(f'File ID: {failed["file_id"]}, Error: {failed["error"]}')

    log.info(f'Reindexing completed.')
    return True


############################
# ReindexKnowledgeBases
############################


@router.post('/metadata/reindex', response_model=dict)
async def reindex_knowledge_base_metadata_embeddings(
    request: Request,
    user=Depends(get_admin_user),
):
    """Batch embed all existing knowledge bases. Admin only.

    NOTE: We intentionally do NOT use Depends(get_session) here.
    This endpoint loops through ALL knowledge bases and calls embed_knowledge_base_metadata()
    for each one, making N external embedding API calls. Holding a session during
    this entire operation would exhaust the connection pool.
    """
    knowledge_bases = Knowledges.get_knowledge_bases()
    log.info(f'Reindexing embeddings for {len(knowledge_bases)} knowledge bases')

    success_count = 0
    for kb in knowledge_bases:
        if await embed_knowledge_base_metadata(request, kb.id, kb.name, kb.description):
            success_count += 1

    log.info(f'Embedding reindex complete: {success_count}/{len(knowledge_bases)}')
    return {'total': len(knowledge_bases), 'success': success_count}


############################
# GetKnowledgeById
############################


class KnowledgeFilesResponse(KnowledgeResponse):
    files: Optional[list[FileMetadataResponse]] = None
    write_access: Optional[bool] = False


@router.get('/{id}', response_model=Optional[KnowledgeFilesResponse])
async def get_knowledge_by_id(id: str, user=Depends(get_verified_user), db: Session = Depends(get_session)):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)

    if knowledge:
        if (
            user.role == 'admin'
            or knowledge.user_id == user.id
            or AccessGrants.has_access(
                user_id=user.id,
                resource_type='knowledge',
                resource_id=knowledge.id,
                permission='read',
                db=db,
            )
        ):
            return KnowledgeFilesResponse(
                **knowledge.model_dump(),
                write_access=(
                    user.id == knowledge.user_id
                    or (user.role == 'admin' and BYPASS_ADMIN_ACCESS_CONTROL)
                    or AccessGrants.has_access(
                        user_id=user.id,
                        resource_type='knowledge',
                        resource_id=knowledge.id,
                        permission='write',
                        db=db,
                    )
                ),
            )
        else:
            raise HTTPException(
                status_code=status.HTTP_401_UNAUTHORIZED,
                detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
            )
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# UpdateKnowledgeById
############################


@router.post('/{id}/update', response_model=Optional[KnowledgeFilesResponse])
async def update_knowledge_by_id(
    request: Request,
    id: str,
    form_data: KnowledgeForm,
    user=Depends(get_verified_user),
):
    # NOTE: We intentionally do NOT use Depends(get_session) here.
    # Database operations manage their own short-lived sessions internally.
    # This prevents holding a connection during embed_knowledge_base_metadata()
    # which makes external embedding API calls (1-5+ seconds).
    knowledge = Knowledges.get_knowledge_by_id(id=id)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    # Is the user the original creator, in a group with write access, or an admin
    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    form_data.access_grants = filter_allowed_access_grants(
        request.app.state.config.USER_PERMISSIONS,
        user.id,
        user.role,
        form_data.access_grants,
        'sharing.public_knowledge',
    )

    knowledge = Knowledges.update_knowledge_by_id(id=id, form_data=form_data)
    if knowledge:
        # Re-embed knowledge base for semantic search
        await embed_knowledge_base_metadata(
            request,
            knowledge.id,
            knowledge.name,
            knowledge.description,
        )
        return KnowledgeFilesResponse(
            **knowledge.model_dump(),
            files=Knowledges.get_file_metadatas_by_id(knowledge.id),
        )
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ID_TAKEN,
        )


############################
# UpdateKnowledgeAccessById
############################


class KnowledgeAccessGrantsForm(BaseModel):
    access_grants: list[dict]


@router.post('/{id}/access/update', response_model=Optional[KnowledgeFilesResponse])
async def update_knowledge_access_by_id(
    request: Request,
    id: str,
    form_data: KnowledgeAccessGrantsForm,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    form_data.access_grants = filter_allowed_access_grants(
        request.app.state.config.USER_PERMISSIONS,
        user.id,
        user.role,
        form_data.access_grants,
        'sharing.public_knowledge',
    )

    AccessGrants.set_access_grants('knowledge', id, form_data.access_grants, db=db)

    return KnowledgeFilesResponse(
        **Knowledges.get_knowledge_by_id(id=id, db=db).model_dump(),
        files=Knowledges.get_file_metadatas_by_id(id, db=db),
    )


############################
# GetKnowledgeFilesById
############################


@router.get('/{id}/files', response_model=KnowledgeFileListResponse)
async def get_knowledge_files_by_id(
    id: str,
    query: Optional[str] = None,
    view_option: Optional[str] = None,
    order_by: Optional[str] = None,
    direction: Optional[str] = None,
    page: Optional[int] = 1,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if not (
        user.role == 'admin'
        or knowledge.user_id == user.id
        or AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='read',
            db=db,
        )
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    page = max(page, 1)

    limit = 30
    skip = (page - 1) * limit

    filter = {}
    if query:
        filter['query'] = query
    if view_option:
        filter['view_option'] = view_option
    if order_by:
        filter['order_by'] = order_by
    if direction:
        filter['direction'] = direction

    return Knowledges.search_files_by_id(id, user.id, filter=filter, skip=skip, limit=limit, db=db)


############################
# AddFileToKnowledge
############################


class KnowledgeFileIdForm(BaseModel):
    file_id: str


@router.post('/{id}/file/add', response_model=Optional[KnowledgeFilesResponse])
def add_file_to_knowledge_by_id(
    request: Request,
    id: str,
    form_data: KnowledgeFileIdForm,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    file = Files.get_file_by_id(form_data.file_id, db=db)
    if not file:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    if not file.data:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.FILE_NOT_PROCESSED,
        )

    # Add content to the vector database
    try:
        process_file(
            request,
            ProcessFileForm(file_id=form_data.file_id, collection_name=id),
            user=user,
            db=db,
        )

        # Add file to knowledge base
        Knowledges.add_file_to_knowledge_by_id(knowledge_id=id, file_id=form_data.file_id, user_id=user.id, db=db)
    except Exception as e:
        log.debug(e)
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e),
        )

    if knowledge:
        return KnowledgeFilesResponse(
            **knowledge.model_dump(),
            files=Knowledges.get_file_metadatas_by_id(knowledge.id, db=db),
        )
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


@router.post('/{id}/file/update', response_model=Optional[KnowledgeFilesResponse])
def update_file_from_knowledge_by_id(
    request: Request,
    id: str,
    form_data: KnowledgeFileIdForm,
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    file = Files.get_file_by_id(form_data.file_id, db=db)
    if not file:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    # Validate the file actually belongs to this knowledge base
    if not Knowledges.has_file(knowledge_id=id, file_id=form_data.file_id, db=db):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    # Remove content from the vector database
    VECTOR_DB_CLIENT.delete(collection_name=knowledge.id, filter={'file_id': form_data.file_id})

    # Add content to the vector database
    try:
        process_file(
            request,
            ProcessFileForm(file_id=form_data.file_id, collection_name=id),
            user=user,
            db=db,
        )
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e),
        )

    if knowledge:
        return KnowledgeFilesResponse(
            **knowledge.model_dump(),
            files=Knowledges.get_file_metadatas_by_id(knowledge.id, db=db),
        )
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# RemoveFileFromKnowledge
############################


@router.post('/{id}/file/remove', response_model=Optional[KnowledgeFilesResponse])
def remove_file_from_knowledge_by_id(
    id: str,
    form_data: KnowledgeFileIdForm,
    delete_file: bool = Query(True),
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    file = Files.get_file_by_id(form_data.file_id, db=db)
    if not file:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    # Validate the file actually belongs to this knowledge base
    if not Knowledges.has_file(knowledge_id=id, file_id=form_data.file_id, db=db):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    Knowledges.remove_file_from_knowledge_by_id(knowledge_id=id, file_id=form_data.file_id, db=db)

    # Remove content from the vector database
    try:
        VECTOR_DB_CLIENT.delete(
            collection_name=knowledge.id, filter={'file_id': form_data.file_id}
        )  # Remove by file_id first

        VECTOR_DB_CLIENT.delete(
            collection_name=knowledge.id, filter={'hash': file.hash}
        )  # Remove by hash as well in case of duplicates
    except Exception as e:
        log.debug('This was most likely caused by bypassing embedding processing')
        log.debug(e)
        pass

    if delete_file:
        try:
            # Remove the file's collection from vector database
            file_collection = f'file-{form_data.file_id}'
            if VECTOR_DB_CLIENT.has_collection(collection_name=file_collection):
                VECTOR_DB_CLIENT.delete_collection(collection_name=file_collection)
        except Exception as e:
            log.debug('This was most likely caused by bypassing embedding processing')
            log.debug(e)
            pass

        # Delete file from database
        Files.delete_file_by_id(form_data.file_id, db=db)

    if knowledge:
        return KnowledgeFilesResponse(
            **knowledge.model_dump(),
            files=Knowledges.get_file_metadatas_by_id(knowledge.id, db=db),
        )
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# DeleteKnowledgeById
############################


@router.delete('/{id}/delete', response_model=bool)
async def delete_knowledge_by_id(id: str, user=Depends(get_verified_user), db: Session = Depends(get_session)):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    log.info(f'Deleting knowledge base: {id} (name: {knowledge.name})')

    # Get all models
    models = Models.get_all_models(db=db)
    log.info(f'Found {len(models)} models to check for knowledge base {id}')

    # Update models that reference this knowledge base
    for model in models:
        if model.meta and hasattr(model.meta, 'knowledge'):
            knowledge_list = model.meta.knowledge or []
            # Filter out the deleted knowledge base
            updated_knowledge = [k for k in knowledge_list if k.get('id') != id]

            # If the knowledge list changed, update the model
            if len(updated_knowledge) != len(knowledge_list):
                log.info(f'Updating model {model.id} to remove knowledge base {id}')
                model.meta.knowledge = updated_knowledge
                # Create a ModelForm for the update
                model_form = ModelForm(
                    id=model.id,
                    name=model.name,
                    base_model_id=model.base_model_id,
                    meta=model.meta,
                    params=model.params,
                    access_grants=model.access_grants,
                    is_active=model.is_active,
                )
                Models.update_model_by_id(model.id, model_form, db=db)

    # Clean up vector DB
    try:
        VECTOR_DB_CLIENT.delete_collection(collection_name=id)
    except Exception as e:
        log.debug(e)
        pass

    # Remove knowledge base embedding
    remove_knowledge_base_metadata_embedding(id)

    result = Knowledges.delete_knowledge_by_id(id=id, db=db)
    return result


############################
# ResetKnowledgeById
############################


@router.post('/{id}/reset', response_model=Optional[KnowledgeResponse])
async def reset_knowledge_by_id(id: str, user=Depends(get_verified_user), db: Session = Depends(get_session)):
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    try:
        VECTOR_DB_CLIENT.delete_collection(collection_name=id)
    except Exception as e:
        log.debug(e)
        pass

    knowledge = Knowledges.reset_knowledge_by_id(id=id, db=db)
    return knowledge


############################
# AddFilesToKnowledge
############################


@router.post('/{id}/files/batch/add', response_model=Optional[KnowledgeFilesResponse])
async def add_files_to_knowledge_batch(
    request: Request,
    id: str,
    form_data: list[KnowledgeFileIdForm],
    user=Depends(get_verified_user),
    db: Session = Depends(get_session),
):
    """
    Add multiple files to a knowledge base
    """
    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    if (
        knowledge.user_id != user.id
        and not AccessGrants.has_access(
            user_id=user.id,
            resource_type='knowledge',
            resource_id=knowledge.id,
            permission='write',
            db=db,
        )
        and user.role != 'admin'
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
        )

    # Batch-fetch all files to avoid N+1 queries
    log.info(f'files/batch/add - {len(form_data)} files')
    file_ids = [form.file_id for form in form_data]
    files = Files.get_files_by_ids(file_ids, db=db)

    # Verify all requested files were found
    found_ids = {file.id for file in files}
    missing_ids = [fid for fid in file_ids if fid not in found_ids]
    if missing_ids:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=f'File {missing_ids[0]} not found',
        )

    # Process files
    try:
        result = await process_files_batch(
            request=request,
            form_data=BatchProcessFilesForm(files=files, collection_name=id),
            user=user,
            db=db,
        )
    except Exception as e:
        log.error(f'add_files_to_knowledge_batch: Exception occurred: {e}', exc_info=True)
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))

    # Only add files that were successfully processed
    successful_file_ids = [r.file_id for r in result.results if r.status == 'completed']
    for file_id in successful_file_ids:
        Knowledges.add_file_to_knowledge_by_id(knowledge_id=id, file_id=file_id, user_id=user.id, db=db)

    # If there were any errors, include them in the response
    if result.errors:
        error_details = [f'{err.file_id}: {err.error}' for err in result.errors]
        return KnowledgeFilesResponse(
            **knowledge.model_dump(),
            files=Knowledges.get_file_metadatas_by_id(knowledge.id, db=db),
            warnings={
                'message': 'Some files failed to process',
                'errors': error_details,
            },
        )

    return KnowledgeFilesResponse(
        **knowledge.model_dump(),
        files=Knowledges.get_file_metadatas_by_id(knowledge.id, db=db),
    )


############################
# ExportKnowledgeById
############################


@router.get('/{id}/export')
async def export_knowledge_by_id(id: str, user=Depends(get_admin_user), db: Session = Depends(get_session)):
    """
    Export a knowledge base as a zip file containing .txt files.
    Admin only.
    """

    knowledge = Knowledges.get_knowledge_by_id(id=id, db=db)
    if not knowledge:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )

    files = Knowledges.get_files_by_id(id, db=db)

    # Create zip file in memory
    zip_buffer = io.BytesIO()
    with zipfile.ZipFile(zip_buffer, 'w', zipfile.ZIP_DEFLATED) as zf:
        for file in files:
            content = file.data.get('content', '') if file.data else ''
            if content:
                # Use original filename with .txt extension
                filename = file.filename
                if not filename.endswith('.txt'):
                    filename = f'{filename}.txt'
                zf.writestr(filename, content)

    zip_buffer.seek(0)

    # Sanitize knowledge name for filename
    # ASCII-safe fallback for the basic filename parameter (latin-1 safe)
    safe_name = ''.join(c if c.isascii() and (c.isalnum() or c in ' -_') else '_' for c in knowledge.name)
    zip_filename = f'{safe_name}.zip'

    # Use RFC 5987 filename* for non-ASCII names so the browser gets the real name
    quoted_name = quote(f'{knowledge.name}.zip')
    content_disposition = f'attachment; filename="{zip_filename}"; filename*=UTF-8\'\'{quoted_name}'

    return StreamingResponse(
        zip_buffer,
        media_type='application/zip',
        headers={'Content-Disposition': content_disposition},
    )
