import json
import time
import uuid
from typing import Optional

from open_webui.apps.webui.internal.db import Base, get_db
from open_webui.apps.webui.models.tags import TagModel, Tag, Tags


from pydantic import BaseModel, ConfigDict
from sqlalchemy import BigInteger, Boolean, Column, String, Text, JSON
from sqlalchemy import or_, func, select, and_, text
from sqlalchemy.sql import exists

####################
# Chat DB Schema
####################


class Chat(Base):
    __tablename__ = "chat"

    id = Column(String, primary_key=True)
    user_id = Column(String)
    title = Column(Text)
    chat = Column(JSON)

    created_at = Column(BigInteger)
    updated_at = Column(BigInteger)

    share_id = Column(Text, unique=True, nullable=True)
    archived = Column(Boolean, default=False)
    pinned = Column(Boolean, default=False, nullable=True)

    meta = Column(JSON, server_default="{}")


class ChatModel(BaseModel):
    model_config = ConfigDict(from_attributes=True)

    id: str
    user_id: str
    title: str
    chat: dict

    created_at: int  # timestamp in epoch
    updated_at: int  # timestamp in epoch

    share_id: Optional[str] = None
    archived: bool = False
    pinned: Optional[bool] = False

    meta: dict = {}


####################
# Forms
####################


class ChatForm(BaseModel):
    chat: dict

class ChatTitleMessagesForm(BaseModel):
    title: str
    messages: list[dict]

class ChatTitleForm(BaseModel):
    title: str


class ChatResponse(BaseModel):
    id: str
    user_id: str
    title: str
    chat: dict
    updated_at: int  # timestamp in epoch
    created_at: int  # timestamp in epoch
    share_id: Optional[str] = None  # id of the chat to be shared
    archived: bool
    pinned: Optional[bool] = False
    meta: dict = {}


class ChatTitleIdResponse(BaseModel):
    id: str
    title: str
    updated_at: int
    created_at: int


class ChatTable:
    def insert_new_chat(self, user_id: str, form_data: ChatForm) -> Optional[ChatModel]:
        with get_db() as db:
            id = str(uuid.uuid4())
            chat = ChatModel(
                **{
                    "id": id,
                    "user_id": user_id,
                    "title": (
                        form_data.chat["title"]
                        if "title" in form_data.chat
                        else "New Chat"
                    ),
                    "chat": form_data.chat,
                    "created_at": int(time.time()),
                    "updated_at": int(time.time()),
                }
            )

            result = Chat(**chat.model_dump())
            db.add(result)
            db.commit()
            db.refresh(result)
            return ChatModel.model_validate(result) if result else None

    def update_chat_by_id(self, id: str, chat: dict) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat_item = db.get(Chat, id)
                chat_item.chat = chat
                chat_item.title = chat["title"] if "title" in chat else "New Chat"
                chat_item.updated_at = int(time.time())
                db.commit()
                db.refresh(chat_item)

                return ChatModel.model_validate(chat_item)
        except Exception:
            return None

    def insert_shared_chat_by_chat_id(self, chat_id: str) -> Optional[ChatModel]:
        with get_db() as db:
            # Get the existing chat to share
            chat = db.get(Chat, chat_id)
            # Check if the chat is already shared
            if chat.share_id:
                return self.get_chat_by_id_and_user_id(chat.share_id, "shared")
            # Create a new chat with the same data, but with a new ID
            shared_chat = ChatModel(
                **{
                    "id": str(uuid.uuid4()),
                    "user_id": f"shared-{chat_id}",
                    "title": chat.title,
                    "chat": chat.chat,
                    "created_at": chat.created_at,
                    "updated_at": int(time.time()),
                }
            )
            shared_result = Chat(**shared_chat.model_dump())
            db.add(shared_result)
            db.commit()
            db.refresh(shared_result)

            # Update the original chat with the share_id
            result = (
                db.query(Chat)
                .filter_by(id=chat_id)
                .update({"share_id": shared_chat.id})
            )
            db.commit()
            return shared_chat if (shared_result and result) else None

    def update_shared_chat_by_chat_id(self, chat_id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                print("update_shared_chat_by_id")
                chat = db.get(Chat, chat_id)
                print(chat)
                chat.title = chat.title
                chat.chat = chat.chat
                db.commit()
                db.refresh(chat)

                return self.get_chat_by_id(chat.share_id)
        except Exception:
            return None

    def delete_shared_chat_by_chat_id(self, chat_id: str) -> bool:
        try:
            with get_db() as db:
                db.query(Chat).filter_by(user_id=f"shared-{chat_id}").delete()
                db.commit()

                return True
        except Exception:
            return False

    def update_chat_share_id_by_id(
        self, id: str, share_id: Optional[str]
    ) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                chat.share_id = share_id
                db.commit()
                db.refresh(chat)
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def toggle_chat_pinned_by_id(self, id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                chat.pinned = not chat.pinned
                chat.updated_at = int(time.time())
                db.commit()
                db.refresh(chat)
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def toggle_chat_archive_by_id(self, id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                chat.archived = not chat.archived
                chat.updated_at = int(time.time())
                db.commit()
                db.refresh(chat)
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def archive_all_chats_by_user_id(self, user_id: str) -> bool:
        try:
            with get_db() as db:
                db.query(Chat).filter_by(user_id=user_id).update({"archived": True})
                db.commit()
                return True
        except Exception:
            return False

    def get_archived_chat_list_by_user_id(
        self, user_id: str, skip: int = 0, limit: int = 50
    ) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                .filter_by(user_id=user_id, archived=True)
                .order_by(Chat.updated_at.desc())
                # .limit(limit).offset(skip)
                .all()
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chat_list_by_user_id(
        self,
        user_id: str,
        include_archived: bool = False,
        skip: int = 0,
        limit: int = 50,
    ) -> list[ChatModel]:
        with get_db() as db:
            query = db.query(Chat).filter_by(user_id=user_id)
            if not include_archived:
                query = query.filter_by(archived=False)
            all_chats = (
                query.order_by(Chat.updated_at.desc())
                # .limit(limit).offset(skip)
                .all()
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chat_title_id_list_by_user_id(
        self,
        user_id: str,
        include_archived: bool = False,
        skip: Optional[int] = None,
        limit: Optional[int] = None,
    ) -> list[ChatTitleIdResponse]:
        with get_db() as db:
            query = db.query(Chat).filter_by(user_id=user_id)
            if not include_archived:
                query = query.filter_by(archived=False)

            query = query.order_by(Chat.updated_at.desc()).with_entities(
                Chat.id, Chat.title, Chat.updated_at, Chat.created_at
            )

            if skip:
                query = query.offset(skip)
            if limit:
                query = query.limit(limit)

            all_chats = query.all()

            # result has to be destrctured from sqlalchemy `row` and mapped to a dict since the `ChatModel`is not the returned dataclass.
            return [
                ChatTitleIdResponse.model_validate(
                    {
                        "id": chat[0],
                        "title": chat[1],
                        "updated_at": chat[2],
                        "created_at": chat[3],
                    }
                )
                for chat in all_chats
            ]

    def get_chat_list_by_chat_ids(
        self, chat_ids: list[str], skip: int = 0, limit: int = 50
    ) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                .filter(Chat.id.in_(chat_ids))
                .filter_by(archived=False)
                .order_by(Chat.updated_at.desc())
                .all()
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chat_by_id(self, id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def get_chat_by_share_id(self, id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.query(Chat).filter_by(share_id=id).first()

                if chat:
                    return self.get_chat_by_id(id)
                else:
                    return None
        except Exception:
            return None

    def get_chat_by_id_and_user_id(self, id: str, user_id: str) -> Optional[ChatModel]:
        try:
            with get_db() as db:
                chat = db.query(Chat).filter_by(id=id, user_id=user_id).first()
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def get_chats(self, skip: int = 0, limit: int = 50) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                # .limit(limit).offset(skip)
                .order_by(Chat.updated_at.desc())
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chats_by_user_id(self, user_id: str) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                .filter_by(user_id=user_id)
                .order_by(Chat.updated_at.desc())
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_pinned_chats_by_user_id(self, user_id: str) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                .filter_by(user_id=user_id, pinned=True)
                .order_by(Chat.updated_at.desc())
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_archived_chats_by_user_id(self, user_id: str) -> list[ChatModel]:
        with get_db() as db:
            all_chats = (
                db.query(Chat)
                .filter_by(user_id=user_id, archived=True)
                .order_by(Chat.updated_at.desc())
            )
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chats_by_user_id_and_search_text(
        self,
        user_id: str,
        search_text: str,
        include_archived: bool = False,
        skip: int = 0,
        limit: int = 60,
    ) -> list[ChatModel]:
        """
        Filters chats based on a search query using Python, allowing pagination using skip and limit.
        """
        search_text = search_text.lower().strip()
        if not search_text:
            return self.get_chat_list_by_user_id(user_id, include_archived, skip, limit)

        with get_db() as db:
            query = db.query(Chat).filter(Chat.user_id == user_id)

            if not include_archived:
                query = query.filter(Chat.archived == False)

            query = query.order_by(Chat.updated_at.desc())

            # Check if the database dialect is either 'sqlite' or 'postgresql'
            dialect_name = db.bind.dialect.name
            if dialect_name == "sqlite":
                # SQLite case: using JSON1 extension for JSON searching
                query = query.filter(
                    (
                        Chat.title.ilike(
                            f"%{search_text}%"
                        )  # Case-insensitive search in title
                        | text(
                            """
                            EXISTS (
                                SELECT 1 
                                FROM json_each(Chat.chat, '$.messages') AS message 
                                WHERE LOWER(message.value->>'content') LIKE '%' || :search_text || '%'
                            )
                            """
                        )
                    ).params(search_text=search_text)
                )
            elif dialect_name == "postgresql":
                # PostgreSQL relies on proper JSON query for search
                query = query.filter(
                    (
                        Chat.title.ilike(
                            f"%{search_text}%"
                        )  # Case-insensitive search in title
                        | text(
                            """
                            EXISTS (
                                SELECT 1
                                FROM json_array_elements(Chat.chat->'messages') AS message
                                WHERE LOWER(message->>'content') LIKE '%' || :search_text || '%'
                            )
                            """
                        )
                    ).params(search_text=search_text)
                )
            else:
                raise NotImplementedError(
                    f"Unsupported dialect: {db.bind.dialect.name}"
                )

            # Perform pagination at the SQL level
            all_chats = query.offset(skip).limit(limit).all()

            # Validate and return chats
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def get_chat_tags_by_id_and_user_id(self, id: str, user_id: str) -> list[TagModel]:
        with get_db() as db:
            chat = db.get(Chat, id)
            tags = chat.meta.get("tags", [])
            return [Tags.get_tag_by_name_and_user_id(tag, user_id) for tag in tags]

    def get_chat_list_by_user_id_and_tag_name(
        self, user_id: str, tag_name: str, skip: int = 0, limit: int = 50
    ) -> list[ChatModel]:
        with get_db() as db:
            query = db.query(Chat).filter_by(user_id=user_id)
            tag_id = tag_name.replace(" ", "_").lower()

            print(db.bind.dialect.name)
            if db.bind.dialect.name == "sqlite":
                # SQLite JSON1 querying for tags within the meta JSON field
                query = query.filter(
                    text(
                        f"EXISTS (SELECT 1 FROM json_each(Chat.meta, '$.tags') WHERE json_each.value = :tag_id)"
                    )
                ).params(tag_id=tag_id)
            elif db.bind.dialect.name == "postgresql":
                # PostgreSQL JSON query for tags within the meta JSON field (for `json` type)
                query = query.filter(
                    text(
                        "EXISTS (SELECT 1 FROM json_array_elements_text(Chat.meta->'tags') elem WHERE elem = :tag_id)"
                    )
                ).params(tag_id=tag_id)
            else:
                raise NotImplementedError(
                    f"Unsupported dialect: {db.bind.dialect.name}"
                )

            all_chats = query.all()
            print("all_chats", all_chats)
            return [ChatModel.model_validate(chat) for chat in all_chats]

    def add_chat_tag_by_id_and_user_id_and_tag_name(
        self, id: str, user_id: str, tag_name: str
    ) -> Optional[ChatModel]:
        tag = Tags.get_tag_by_name_and_user_id(tag_name, user_id)
        if tag is None:
            tag = Tags.insert_new_tag(tag_name, user_id)
        try:
            with get_db() as db:
                chat = db.get(Chat, id)

                tag_id = tag.id
                if tag_id not in chat.meta.get("tags", []):
                    chat.meta = {
                        **chat.meta,
                        "tags": chat.meta.get("tags", []) + [tag_id],
                    }

                db.commit()
                db.refresh(chat)
                return ChatModel.model_validate(chat)
        except Exception:
            return None

    def count_chats_by_tag_name_and_user_id(self, tag_name: str, user_id: str) -> int:
        with get_db() as db:  # Assuming `get_db()` returns a session object
            query = db.query(Chat).filter_by(user_id=user_id)

            # Normalize the tag_name for consistency
            tag_id = tag_name.replace(" ", "_").lower()

            if db.bind.dialect.name == "sqlite":
                # SQLite JSON1 support for querying the tags inside the `meta` JSON field
                query = query.filter(
                    text(
                        f"EXISTS (SELECT 1 FROM json_each(Chat.meta, '$.tags') WHERE json_each.value = :tag_id)"
                    )
                ).params(tag_id=tag_id)

            elif db.bind.dialect.name == "postgresql":
                # PostgreSQL JSONB support for querying the tags inside the `meta` JSON field
                query = query.filter(
                    text(
                        "EXISTS (SELECT 1 FROM json_array_elements_text(Chat.meta->'tags') elem WHERE elem = :tag_id)"
                    )
                ).params(tag_id=tag_id)

            else:
                raise NotImplementedError(
                    f"Unsupported dialect: {db.bind.dialect.name}"
                )

            # Get the count of matching records
            count = query.count()

            # Debugging output for inspection
            print(f"Count of chats for tag '{tag_name}':", count)

            return count

    def delete_tag_by_id_and_user_id_and_tag_name(
        self, id: str, user_id: str, tag_name: str
    ) -> bool:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                tags = chat.meta.get("tags", [])
                tag_id = tag_name.replace(" ", "_").lower()

                tags = [tag for tag in tags if tag != tag_id]
                chat.meta = {
                    **chat.meta,
                    "tags": tags,
                }
                db.commit()
                return True
        except Exception:
            return False

    def delete_all_tags_by_id_and_user_id(self, id: str, user_id: str) -> bool:
        try:
            with get_db() as db:
                chat = db.get(Chat, id)
                chat.meta = {
                    **chat.meta,
                    "tags": [],
                }
                db.commit()

                return True
        except Exception:
            return False

    def delete_chat_by_id(self, id: str) -> bool:
        try:
            with get_db() as db:
                db.query(Chat).filter_by(id=id).delete()
                db.commit()

                return True and self.delete_shared_chat_by_chat_id(id)
        except Exception:
            return False

    def delete_chat_by_id_and_user_id(self, id: str, user_id: str) -> bool:
        try:
            with get_db() as db:
                db.query(Chat).filter_by(id=id, user_id=user_id).delete()
                db.commit()

                return True and self.delete_shared_chat_by_chat_id(id)
        except Exception:
            return False

    def delete_chats_by_user_id(self, user_id: str) -> bool:
        try:
            with get_db() as db:
                self.delete_shared_chats_by_user_id(user_id)

                db.query(Chat).filter_by(user_id=user_id).delete()
                db.commit()

                return True
        except Exception:
            return False

    def delete_shared_chats_by_user_id(self, user_id: str) -> bool:
        try:
            with get_db() as db:
                chats_by_user = db.query(Chat).filter_by(user_id=user_id).all()
                shared_chat_ids = [f"shared-{chat.id}" for chat in chats_by_user]

                db.query(Chat).filter(Chat.user_id.in_(shared_chat_ids)).delete()
                db.commit()

                return True
        except Exception:
            return False


Chats = ChatTable()
