use std::time::Duration;

use grammers_client::{types::Message, Client, InputMessage, Update};

use crate::{bot::handlers::Handler, utils::messages::get_message};

#[derive(Clone)]
pub struct Rotator;

async fn rotator(replied_message: Message, text: String) {
    let mut skip = 1;
    let start = std::time::SystemTime::now();
    let mut current = std::time::SystemTime::now();
    while current
        .duration_since(start)
        .map(|dur| dur.as_secs())
        .unwrap_or(100)
        < 10
    {
        let rotated = text
            .chars()
            .cycle()
            .skip(skip)
            .take(text.len())
            .collect::<String>();
        skip += 1;
        if skip == rotated.len() {
            skip = 1;
        }
        replied_message.edit(rotated).await.ok();
        current = std::time::SystemTime::now();
        tokio::time::sleep(Duration::from_millis(200)).await;
    }
    replied_message.delete().await.ok();
}

#[async_trait::async_trait]
impl Handler for Rotator {
    async fn react(&self, _: &Client, update: &Update) -> anyhow::Result<()> {
        let Some(message) = get_message(update) else {
            return Ok(());
        };
        if let Some(text) = message.text().strip_prefix(".rl").map(str::trim) {
            let replied_message = message.reply(InputMessage::from(text).silent(true)).await?;
            tokio::spawn(rotator(replied_message, text.to_string()));
        }
        Ok(())
    }
}