use regex::Regex;
use twilight_http::Client;
use twilight_gateway::Shard;
use twilight_mention::ParseMention;
use twilight_model::channel::Message;
use twilight_model::id::{marker::{ChannelMarker, UserMarker}, Id};
use std::{collections::HashMap, sync::Arc};
use tokio::sync::Mutex;

#[derive(Clone)]
pub struct Member {
    pub name: String,
    pub discord_token: String,
    pub user_id: Arc<Mutex<Option<Id<UserMarker>>>>,
    pub message_pattern: Regex,
    pub shard: Arc<Mutex<Shard>>,
    pub client: Arc<Mutex<Client>>,
}

#[derive(Clone)]
pub struct System {
    pub followed_user: Id<UserMarker>,
    pub command_prefix: String,
    pub members: Vec<Member>,
    pub message_cache: Arc<Mutex<HashMap<Id<ChannelMarker>, (Member, Message)>>>
}

#[derive(Clone)]
pub enum Response {
    Proxy {member: Member, content: String},
    Noop {delete_source: bool},
}

pub enum SystemThreadCommand {
    Restart,
    ReloadConfig,
    ShutdownSystem,
    ShutdownAll,
}

impl System {
    pub async fn resolve_mention<'system>(&'system self, maybe_mention: Option<&str>) -> Option<&'system Member> {
        if let Some(mention) = maybe_mention {
            if let Ok(mention) = Id::<UserMarker>::parse(mention) {
                return self.get_member_by_id(mention).await;
            }
        }

        None
    }

    pub async fn get_member_by_id<'system>(&'system self, search_id: Id<UserMarker>) -> Option<&'system Member> {
        for member in &self.members {
            let is_member = {member.user_id.lock().await.map(|id| id == search_id).unwrap_or(false)};

            if is_member {
                return Some(&member)
            }
        }

        return None
    }

    pub async fn cache_most_recent_message(&self, channel: Id<ChannelMarker>, message: Message, member: Member) {
        self.message_cache.lock().await.insert(channel, (member, message));
    }

    pub async fn get_most_recent_message(&self, channel: Id<ChannelMarker>) -> Option<(Message, Member)> {
        self.message_cache.lock().await.get(&channel).map(|(member, message)| (message.clone(), member.clone()))
    }
}