"""Message routes"""
import json
from fastapi import APIRouter, Depends, Response
from fastapi.responses import StreamingResponse
from pydantic import BaseModel
from sqlalchemy.orm import Session
from datetime import datetime

from luxx.database import get_db
from luxx.models import Conversation, Message, User
from luxx.routes.auth import get_current_user
from luxx.services.chat import chat_service
from luxx.utils.helpers import generate_id, success_response, error_response


router = APIRouter(prefix="/messages", tags=["Messages"])


class MessageCreate(BaseModel):
    """Create message model"""
    conversation_id: str
    content: str


class MessageResponse(BaseModel):
    """Message response model"""
    id: str
    role: str
    content: str
    token_count: int


@router.get("/", response_model=dict)
def list_messages(
    conversation_id: str,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get message list"""
    conversation = db.query(Conversation).filter(
        Conversation.id == conversation_id,
        Conversation.user_id == current_user.id
    ).first()
    
    if not conversation:
        return error_response("Conversation not found", 404)
    
    messages = db.query(Message).filter(
        Message.conversation_id == conversation_id
    ).order_by(Message.created_at).all()
    
    return success_response(data={
        "messages": [m.to_dict() for m in messages],
        "title": conversation.title,
        "first_message": next((m.content[:50] + ('...' if len(m.content) > 50 else '') for m in messages if m.role == 'user'), None)
    })


@router.post("/", response_model=dict)
def send_message(
    data: MessageCreate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Send message (non-streaming)"""
    conversation = db.query(Conversation).filter(
        Conversation.id == data.conversation_id,
        Conversation.user_id == current_user.id
    ).first()
    
    if not conversation:
        return error_response("Conversation not found", 404)
    
    user_message = Message(
        id=generate_id("msg"),
        conversation_id=data.conversation_id,
        role="user",
        content=data.content,
        token_count=len(data.content) // 4
    )
    db.add(user_message)
    
    from datetime import datetime, timezone, timedelta
    conversation.updated_at = datetime.now(timezone(timedelta(hours=8)))
    
    response = chat_service.non_stream_response(
        conversation=conversation,
        user_message=data.content,
        tools_enabled=False
    )
    
    if not response.get("success"):
        return error_response(response.get("error", "Failed to generate response"), 500)
    
    ai_content = response.get("content", "")
    
    ai_message = Message(
        id=generate_id("msg"),
        conversation_id=data.conversation_id,
        role="assistant",
        content=ai_content,
        token_count=len(ai_content) // 4
    )
    db.add(ai_message)
    db.commit()
    
    return success_response(data={
        "user_message": user_message.to_dict(),
        "assistant_message": ai_message.to_dict()
    })


@router.post("/stream")
async def stream_message(
    data: MessageCreate,
    tools_enabled: bool = True,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Send message (streaming response - SSE)"""
    conversation = db.query(Conversation).filter(
        Conversation.id == data.conversation_id,
        Conversation.user_id == current_user.id
    ).first()
    
    if not conversation:
        return error_response("Conversation not found", 404)
    
    user_message = Message(
        id=generate_id("msg"),
        conversation_id=data.conversation_id,
        role="user",
        content=data.content,
        token_count=len(data.content) // 4
    )
    db.add(user_message)
    conversation.updated_at = datetime.now()
    db.commit()
    
    async def event_generator():
        async for sse_str in chat_service.stream_response(
            conversation=conversation,
            user_message=data.content,
            tools_enabled=tools_enabled
        ):
            # Chat service returns raw SSE strings (including done event)
            yield sse_str
    
    return StreamingResponse(
        event_generator(),
        media_type="text/event-stream",
        headers={
            "Cache-Control": "no-cache",
            "Connection": "keep-alive",
            "X-Accel-Buffering": "no"
        }
    )


@router.delete("/{message_id}", response_model=dict)
def delete_message(
    message_id: str,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Delete message"""
    message = db.query(Message).join(Conversation).filter(
        Message.id == message_id,
        Conversation.user_id == current_user.id
    ).first()
    
    if not message:
        return error_response("Message not found", 404)
    
    db.delete(message)
    db.commit()
    
    return success_response(message="Message deleted successfully")