from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse
from pydantic import BaseModel
from typing import List, Optional
import os
try:
    from . import chat, voice, database
except ImportError:
    import chat, voice, database
import traceback

app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Initialize database on startup
@app.on_event("startup")
async def startup_event():
    database.init_db()

class ChatRequest(BaseModel):
    message: str
    # history is now optional/deprecated as we use session_id, but keeping for backward compatibility if needed
    history: List[dict] = [] 

class SessionCreateRequest(BaseModel):
    name: str = "New Chat"
    user_id: str

class VoiceRequest(BaseModel):
    text: str
    voice: str

@app.get("/")
async def root():
    return {"message": "AI Girlfriend API"}

@app.get("/sessions/{user_id}")
async def get_sessions(user_id: str):
    return database.get_sessions(user_id)

@app.post("/sessions")
async def create_session(request: SessionCreateRequest):
    return database.create_session(request.user_id, request.name)

@app.delete("/sessions/{session_id}")
async def delete_session(session_id: str):
    database.delete_session(session_id)
    return {"message": "Session deleted"}

@app.get("/sessions/{session_id}/messages")
async def get_session_messages(session_id: str):
    return database.get_messages(session_id)

@app.post("/sessions/{session_id}/chat")
async def chat_session_endpoint(session_id: str, request: ChatRequest):
    try:
        # Get existing history from DB
        db_history = database.get_messages(session_id)
        
        # Convert to format expected by chat.py (list of dicts with role/content)
        history_for_model = [{"role": msg["role"], "content": msg["content"]} for msg in db_history]
        
        # Get response from AI
        response_text = chat.get_chat_response(request.message, history_for_model)
        
        # Save user message and AI response to DB
        database.add_message(session_id, "user", request.message)
        database.add_message(session_id, "assistant", response_text)
        
        # If this was the first message (history was empty before this turn), generate a summary
        if not db_history:
            try:
                summary = chat.generate_summary(request.message, response_text)
                database.update_session_name(session_id, summary)
            except Exception as e:
                print(f"Failed to generate summary: {e}")
        
        return {"response": response_text}
    except Exception as e:
        traceback.print_exc()
        raise HTTPException(status_code=500, detail=str(e))

# Legacy endpoint - keeping for now or can be removed if frontend is fully updated
@app.post("/chat")
async def chat_endpoint(request: ChatRequest):
    try:
        response = chat.get_chat_response(request.message, request.history)
        return {"response": response}
    except Exception as e:
        traceback.print_exc() # Print error to console
        raise HTTPException(status_code=500, detail=str(e))

@app.get("/voices")
async def voices_endpoint():
    return voice.get_voices()

@app.post("/speak")
async def speak_endpoint(request: VoiceRequest):
    try:
        audio_path = await voice.generate_audio(request.text, request.voice)
        return FileResponse(audio_path, media_type="audio/mpeg", filename="response.mp3")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

from fastapi.staticfiles import StaticFiles
from fastapi.responses import FileResponse

# Mount static files if they exist (for production/served build)
frontend_dist = os.path.join(os.path.dirname(__file__), "../frontend/dist")
assets_path = os.path.join(frontend_dist, "assets")

if os.path.exists(assets_path):
    app.mount("/assets", StaticFiles(directory=assets_path), name="assets")

@app.get("/{full_path:path}")
async def serve_frontend(full_path: str):
    # Only serve if dist exists
    if os.path.exists(frontend_dist):
        # Serve index.html for any other path (SPA routing)
        # Check if file exists in dist, else serve index.html
        target_file = os.path.join(frontend_dist, full_path)
        if full_path and os.path.exists(target_file):
            return FileResponse(target_file)
        return FileResponse(os.path.join(frontend_dist, "index.html"))
    
    # If dist doesn't exist, just return a message or 404 for frontend routes
    # This allows backend to run even if frontend isn't built
    if full_path == "":
        return {"message": "Backend is running. Frontend build not found. Use 'npm run dev' for frontend development."}
    raise HTTPException(status_code=404, detail="Frontend build not found")