discord-bot/src/main.rs

use std::env;
use std::sync::Arc;
use std::sync::atomic::{AtomicBool, Ordering};
use std::time::Duration;
use dotenvy::dotenv;
use serenity::async_trait;
use serenity::model::gateway::{GatewayIntents, Ready};
use serenity::model::guild::Member;
use serenity::model::id::GuildId;
use serenity::prelude::*;
use serenity::model::prelude::RoleId;

struct Handler {
    is_loop_running: AtomicBool,
}

#[async_trait]
impl EventHandler for Handler {
    async fn guild_member_addition(&self, ctx: Context, mut new_member: Member) {
        let config_lock = {
            let data_read = ctx.data.read().await;
            data_read.get::<Config>().expect("Expected Config in TypeMap.").clone()
        };
        let config = config_lock.read().await;
        
        let members_lock = {
            let data_read = ctx.data.read().await;
            data_read.get::<Members>().expect("Expected Members in TypeMap.").clone()
        };
        let members = members_lock.read().await;

        if members.contains(&new_member.user.name) {
            let mut roles = vec![];

            if !new_member.roles.contains(&config.member_role_past){
                roles.push(config.member_role_past);
            }
            if !new_member.roles.contains(&config.member_role_current){
                roles.push(config.member_role_current);
            }

            if let Err(e) =  new_member.add_roles(&ctx, &roles).await {
                println!("{:?}", e);
            }
        }
    }

    async fn ready(&self, ctx: Context, ready: Ready) {
        let ctx = Arc::new(ctx);
        println!("{} is connected!", ready.user.name);
        
        let config_lock = {
            let data_read = ctx.data.read().await;
            data_read.get::<Config>().expect("Expected Config in TypeMap.").clone()
        };
        let config = config_lock.read().await;
        let timing_update = config.timing_update;
        let timing_fetch = config.timing_fetch;

        if !self.is_loop_running.load(Ordering::Relaxed) {
            // We have to clone the Arc, as it gets moved into the new thread.
            let ctx1 = Arc::clone(&ctx);
            // tokio::spawn creates a new green thread that can run in parallel with the rest of
            // the application.
            tokio::spawn(async move {
                loop {
                    // We clone Context again here, because Arc is owned, so it moves to the
                    // new function.
                    bulk_check(Arc::clone(&ctx1)).await;
                    tokio::time::sleep(Duration::from_secs(timing_update)).await;
                }
            });
            
            let ctx2 = Arc::clone(&ctx);
            tokio::spawn(async move {
                loop {
                    fetch_accounts(Arc::clone(&ctx2)).await;
                    tokio::time::sleep(Duration::from_secs(timing_fetch)).await;
                }
            });

            // Now that the loop is running, we set the bool to true
            self.is_loop_running.swap(true, Ordering::Relaxed);
        }
    }
}

#[derive(Default, Debug)]
struct MembersCount {
    members: i32,
    members_current: i32,
}
struct MemberCounter;
impl TypeMapKey for MemberCounter {
    type Value = Arc<RwLock<MembersCount>>;
}

struct Members;
impl TypeMapKey for Members {
    type Value = Arc<RwLock<Vec<String>>>;
}
async fn bulk_check(ctx: Arc<Context>){
    let config_lock = {
        let data_read = ctx.data.read().await;
        data_read.get::<Config>().expect("Expected Config in TypeMap.").clone()
    };
    let config = config_lock.read().await;
    
    let members_lock = {
        let data_read = ctx.data.read().await;
        data_read.get::<Members>().expect("Expected Members in TypeMap.").clone()
    };
    let members = members_lock.read().await;
    
    let mut roles_set = [0,0,0];
    let mut res = MembersCount {
        members: 0,
        members_current: 0,
    };
    if let Ok(x) = config.server.members(&ctx, None, None).await {
        for mut member in x {
            if members.contains(&member.user.name) {
                let mut roles = vec![];

                if !member.roles.contains(&config.member_role_past){
                    roles_set[0] += 1;
                    roles.push(config.member_role_past);
                }
                if !member.roles.contains(&config.member_role_current){
                    roles_set[1] += 1;
                    roles.push(config.member_role_current);
                }

                if let Err(e) =  member.add_roles(&ctx, &roles).await {
                    println!("{:?}", e);
                }
            } else if member.roles.contains(&config.member_role_current) {
                roles_set[2] += 1;
                // if theya re not a current member and have the role then remove it
                if let Err(e) = member.remove_role(&ctx, &config.member_role_current).await {
                    println!("{:?}", e);
                }
            }

            if member.roles.contains(&config.member_role_past){
                res.members += 1;
            }
            if member.roles.contains(&config.member_role_current){
                res.members_current += 1;
            }
        }
    }
    // small bit of logging to note changes over time
    println!("Changes: New: +{}, Current: +{}/-{}", roles_set[0], roles_set[1], roles_set[2]);

    {
        let data_read = ctx.data.read().await;
        let counter_lock = data_read.get::<MemberCounter>().expect("Expected MemberCounter in TypeMap.").clone();
        // The HashMap of CommandCounter is wrapped in an RwLock; since we want to write to it, we will
        // open the lock in write mode.
        let mut counter = counter_lock.write().await;

        // And we write the amount of times the command has been called to it.
        counter.members_current = res.members_current;
        counter.members = res.members;
    };
}

async fn fetch_accounts(ctx: Arc<Context>){
    let config_lock = {
        let data_read = ctx.data.read().await;
        data_read.get::<Config>().expect("Expected Config in TypeMap.").clone()
    };
    let config = config_lock.read().await;
    let auth = &config.auth;
    let ldap_api = &config.ldap_api;
    let url = format!("{}/ldap/discord?auth={}", ldap_api, auth);
    if let Ok(result) = surf::get(url).recv_json::<Vec<String>>().await {
        let members_lock = {
            let data_read = ctx.data.read().await;
            data_read.get::<Members>().expect("Expected Members in TypeMap.").clone()
        };
        let mut accounts = members_lock.write().await;
        *accounts = result;
    }
}

#[tokio::main]
async fn main() {
    let config = get_config();

    // Intents are a bitflag, bitwise operations can be used to dictate which intents to use
    let intents = GatewayIntents::GUILDS | GatewayIntents::GUILD_MESSAGES | GatewayIntents::MESSAGE_CONTENT | GatewayIntents::GUILD_MEMBERS;
    // Build our client.
    let mut client = Client::builder(&config.discord_token, intents)
      .event_handler(Handler { is_loop_running: AtomicBool::new(false)})
      .await
      .expect("Error creating client");
    
    {
        let mut data = client.data.write().await;
        
        // will keep track of how many past and current members we have
        data.insert::<MemberCounter>(Arc::new(RwLock::new(MembersCount::default())));
        
        // a list of all current members
        data.insert::<Members>(Arc::new(RwLock::new(vec![])));

        data.insert::<Config>(Arc::new(RwLock::new(config)));
    }
    
    
    // Finally, start a single shard, and start listening to events.
    //
    // Shards will automatically attempt to reconnect, and will perform
    // exponential backoff until it reconnects.
    if let Err(why) = client.start().await {
        println!("Client error: {:?}", why);
    }
}


struct Config {
    server: GuildId,
    member_role_current: RoleId,
    member_role_past: RoleId,
    ldap_api: String,
    auth: String,
    timing_update: u64,
    timing_fetch: u64,
    discord_token: String,
}
impl TypeMapKey for Config {
    type Value = Arc<RwLock<Config>>;
}
fn get_config() -> Config {
    dotenv().ok();

    // reasonable defaults
    let mut config = Config {
        server: Default::default(),
        member_role_current: Default::default(),
        member_role_past: Default::default(),
        ldap_api: "https://api.account.skynet.ie".to_string(),
        auth: "".to_string(),
        timing_update: 0,
        timing_fetch: 0,
        discord_token: "".to_string(),
    };

    if let Ok(x) = env::var("DISCORD_SERVER") {
        config.server = GuildId::from(str_to_num::<u64>(&x));
    }
    if let Ok(x) = env::var("DISCORD_ROLE_CURRENT") {
        config.member_role_current = RoleId::from(str_to_num::<u64>(&x));
    }
    if let Ok(x) = env::var("DISCORD_ROLE_PAST") {
        config.member_role_past = RoleId::from(str_to_num::<u64>(&x));
    }
    if let Ok(x) = env::var("LDAP_API") {
        config.ldap_api = x.trim().to_string();
    }
    if let Ok(x) = env::var("LDAP_DISCORD_AUTH") {
        config.auth = x.trim().to_string();
    }
    if let Ok(x) = env::var("DISCORD_TIMING_UPDATE") {
        config.timing_update = str_to_num::<u64>(&x);
    }
    if let Ok(x) = env::var("DISCORD_TIMING_FETCH") {
        config.timing_fetch = str_to_num::<u64>(&x);
    }
    if let Ok(x) = env::var("DISCORD_TOKEN") {
        config.discord_token = x.trim().to_string();
    }
    config
}

fn str_to_num<T: std::str::FromStr + Default>(x: &str) -> T {
    x.trim().parse::<T>().unwrap_or_default()
}