use crate::state::AppState;
use crate::sync::firehose::SequencedEvent;
use crate::sync::frame::{CommitFrame, Frame, FrameData};
use cid::Cid;
use jacquard_repo::car::write_car;
use jacquard_repo::storage::BlockStore;
use std::fs;
use std::str::FromStr;
use tokio::fs::File;
use tokio::io::AsyncReadExt;
use uuid::Uuid;

pub async fn format_event_for_sending(
    state: &AppState,
    event: SequencedEvent,
) -> Result<Vec<u8>, anyhow::Error> {
    let block_cids_str = event.blocks_cids.clone().unwrap_or_default();
    let mut frame: CommitFrame = event.into();

    let mut car_bytes = Vec::new();
    if !block_cids_str.is_empty() {
        let temp_path = format!("/tmp/{}.car", Uuid::new_v4());
        let mut blocks = std::collections::BTreeMap::new();

        for cid_str in block_cids_str {
            let cid = Cid::from_str(&cid_str)?;
            let data = state
                .block_store
                .get(&cid)
                .await?
                .ok_or_else(|| anyhow::anyhow!("Block not found: {}", cid))?;
            blocks.insert(cid, data);
        }

        let root = Cid::from_str(&frame.commit)?;
        write_car(&temp_path, vec![root], blocks).await?;

        let mut file = File::open(&temp_path).await?;
        file.read_to_end(&mut car_bytes).await?;
        fs::remove_file(&temp_path)?;
    }
    frame.blocks = car_bytes;

    let frame = Frame {
        op: 1,
        data: FrameData::Commit(Box::new(frame)),
    };

    let mut bytes = Vec::new();
    serde_ipld_dagcbor::to_writer(&mut bytes, &frame)?;
    Ok(bytes)
}