use uuid::Uuid;

use crate::cache::redis::AppRedis;
use crate::error::{AppError, AppResult};
use crate::service::im::util::{TYPING_PREFIX, TYPING_TTL_SECS};
use ::redis::Cmd;

pub fn set_typing(
    redis: &AppRedis,
    channel_id: Uuid,
    thread_id: Option<Uuid>,
    user_id: Uuid,
) -> AppResult<()> {
    let key = typing_key(channel_id, thread_id, user_id);
    let mut conn = redis.get_connection()?;
    Cmd::new()
        .arg("SETEX")
        .arg(&key)
        .arg(TYPING_TTL_SECS as u64)
        .arg("1")
        .query::<()>(&mut *conn.inner_mut())?;
    Ok(())
}

pub fn clear_typing(
    redis: &AppRedis,
    channel_id: Uuid,
    thread_id: Option<Uuid>,
    user_id: Uuid,
) -> AppResult<()> {
    let key = typing_key(channel_id, thread_id, user_id);
    let mut conn = redis.get_connection()?;
    Cmd::new()
        .arg("DEL")
        .arg(&key)
        .query::<()>(&mut *conn.inner_mut())?;
    Ok(())
}

pub fn get_typing_users(
    redis: &AppRedis,
    channel_id: Uuid,
    thread_id: Option<Uuid>,
) -> AppResult<Vec<Uuid>> {
    let pattern = match thread_id {
        Some(tid) => format!("{TYPING_PREFIX}{channel_id}:{tid}:*"),
        None => format!("{TYPING_PREFIX}{channel_id}:*"),
    };
    let mut conn = redis.get_connection()?;
    let keys: Vec<String> = Cmd::new()
        .arg("KEYS")
        .arg(&pattern)
        .query(&mut *conn.inner_mut())
        .map_err(AppError::Redis)?;
    let mut ids = Vec::with_capacity(keys.len());
    for key in &keys {
        if let Some(part) = key.rsplit(':').next()
            && let Ok(uid) = part.parse::<Uuid>()
        {
            ids.push(uid);
        }
    }
    Ok(ids)
}

fn typing_key(channel_id: Uuid, thread_id: Option<Uuid>, user_id: Uuid) -> String {
    match thread_id {
        Some(tid) => format!("{TYPING_PREFIX}{channel_id}:{tid}:{user_id}"),
        None => format!("{TYPING_PREFIX}{channel_id}:{user_id}"),
    }
}