import asyncio
import uuid

from sqlalchemy import delete
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.adventure_chunk import AdventureChunk
from app.rag.chunking import chunk_text
from app.rag.embeddings import embed_texts

EMBED_BATCH_SIZE = 32


async def ingest_adventure_text(session: AsyncSession, game_id: uuid.UUID, text: str) -> int:
    """Chunks and embeds a player-supplied adventure text, scoped to one game. Safe to call
    again for the same game (e.g. future re-ingest) — previous chunks are cleared first."""
    await session.execute(delete(AdventureChunk).where(AdventureChunk.game_id == game_id))

    chunks = chunk_text(text)
    if not chunks:
        await session.commit()
        return 0

    for batch_start in range(0, len(chunks), EMBED_BATCH_SIZE):
        batch = chunks[batch_start : batch_start + EMBED_BATCH_SIZE]
        # embed_texts is a synchronous, CPU-bound sentence-transformers call — run it off the
        # event loop so a large adventure doesn't stall other concurrent requests/WS connections.
        embeddings = await asyncio.to_thread(embed_texts, batch)
        for i, (content, embedding) in enumerate(zip(batch, embeddings)):
            session.add(
                AdventureChunk(
                    game_id=game_id,
                    chunk_index=batch_start + i,
                    content=content,
                    embedding=embedding,
                )
            )
        await session.commit()

    return len(chunks)