from fastapi import APIRouter, Depends, Request, HTTPException
from app.api.deps import get_current_module
from app.models.module import Module
from sqlalchemy.orm import Session
from app.core.database import get_db
from app.core.limiter import limiter
from app.core.config import settings
from pydantic import BaseModel
import httpx

router = APIRouter()

GEMINI_API_BASE = "https://generativelanguage.googleapis.com/v1beta"
GEMINI_LIVE_WSS_URI = (
    "wss://generativelanguage.googleapis.com/ws/"
    "google.ai.generativelanguage.v1beta.GenerativeService.BidiGenerateContent"
)


class LiveTokenRequest(BaseModel):
    model: str = "gemini-2.0-flash-live-001"
    system_instruction: str
    voice_name: str | None = "Puck"


@router.post("/live-token")
@limiter.limit(settings.RATE_LIMIT)
async def generate_live_token(
    request: Request,
    body: LiveTokenRequest,
    module: Module = Depends(get_current_module),
    db: Session = Depends(get_db),
):
    if not settings.GOOGLE_API_KEY or settings.GOOGLE_API_KEY == "your-google-api-key":
        return {
            "token": "mock-ephemeral-token",
            "expires_at": "2026-04-02T02:00:00Z",
            "websocket_uri": GEMINI_LIVE_WSS_URI,
        }

    payload = {
        "systemInstruction": {
            "parts": [{"text": body.system_instruction}]
        },
        "generationConfig": {
            "responseModalities": ["AUDIO", "TEXT"],
        },
    }

    if body.voice_name:
        payload["generationConfig"]["speechConfig"] = {
            "voiceConfig": {
                "prebuiltVoiceConfig": {"voiceName": body.voice_name}
            }
        }

    async with httpx.AsyncClient(timeout=30.0) as client:
        response = await client.post(
            f"{GEMINI_API_BASE}/models/{body.model}:generateEphemeralToken",
            json=payload,
            params={"key": settings.GOOGLE_API_KEY},
        )

    if response.status_code != 200:
        raise HTTPException(
            status_code=502,
            detail=f"Gemini token API error {response.status_code}: {response.text}",
        )

    data = response.json()

    # Response name is "ephemeralTokens/{token_value}"
    token_value = data.get("name", "").split("/")[-1]
    expires_at = data.get("expireTime", "")

    if module:
        module.ingress_tokens += 1
        module.total_tokens += 1
        db.commit()

    return {
        "token": token_value,
        "expires_at": expires_at,
        "websocket_uri": GEMINI_LIVE_WSS_URI,
    }