use std::collections::BTreeSet;

use tokio::{io::BufWriter, net::TcpStream};

use crate::{
    error_structs::SenderError,
    sender::IrcResponseCodes,
    user::{User, UserUnwrapped},
};

#[derive(Clone, Debug, Hash, Eq, PartialEq)]
pub struct Channel {
    pub name: String,
    pub joined_users: BTreeSet<UserUnwrapped>,
}

impl Channel {
    pub fn add_user(&mut self, user: UserUnwrapped) {
        self.joined_users.insert(user);
    }

    pub fn new_channel(name: String, user: UserUnwrapped) -> Self {
        Channel {
            name,
            joined_users: BTreeSet::from([user]),
        }
    }

    pub async fn names_list_send(
        &self,
        user: UserUnwrapped,
        channel: &Channel,
        writer: &mut BufWriter<TcpStream>,
        hostname: &str,
    ) -> Result<(), SenderError> {
        let mut members = Vec::new();

        for member in self.clone().joined_users {
            members.push(member.nickname);
        }

        for member in channel.joined_users.clone() {
            members.push(member.nickname);
        }

        members.sort();
        members.dedup();

        IrcResponseCodes::NameReply
            .into_irc_response(
                user.nickname.clone(),
                format!("= {} :{}", self.name.clone(), members.join(" ")),
            )
            .send(hostname, writer, false)
            .await?;
        IrcResponseCodes::EndOfNames
            .into_irc_response(
                user.nickname.clone(),
                format!("{} :End of /NAMES list", self.name.clone()),
            )
            .send(hostname, writer, false)
            .await?;

        Ok(())
    }

    pub async fn send_topic(
        &self,
        user: UserUnwrapped,
        writer: &mut BufWriter<TcpStream>,
        hostname: &str,
    ) -> Result<(), SenderError> {
        IrcResponseCodes::NoTopic
            .into_irc_response(
                user.nickname.clone(),
                format!("{} :No topic is set", self.name.clone()),
            )
            .send(hostname, writer, false)
            .await?;

        Ok(())
    }
}