extern crate serenity;

use serenity::Client;
use std::env;

fn main() {
    // Configure the client with your Discord bot token in the environment.
    let token = env::var("DISCORD_TOKEN")
        .expect("Expected a token in the environment");

    // Create a new instance of the Client, logging in as a bot. This will
    // automatically prepend your bot token with "Bot ", which is a requirement
    // by Discord for bot users.
    let mut client = Client::login(&token);

    // Set a handler for the `on_message` event - so that whenever a new message
    // is received - the closure (or function) passed will be called.
    //
    // Event handlers are dispatched through multi-threading, and so multiple
    // of a single event can be dispatched simultaneously.
    client.on_message(|_ctx, msg| {
        if msg.content == "!ping" {
            // Sending a message can fail, due to a network error, an
            // authentication error, or lack of permissions to post in the
            // channel, so log to stdout when some error happens, with a
            // description of it.
            if let Err(why) = msg.channel_id.say("Pong!") {
                println!("Error sending message: {:?}", why);
            }
        }
    });

    // Set a handler to be called on the `on_ready` event. This is called when a
    // shard is booted, and a READY payload is sent by Discord. This payload
    // contains data like the current user's guild Ids, current user data,
    // private channels, and more.
    //
    // In this case, just print what the current user's username is.
    client.on_ready(|_ctx, ready| {
        println!("{} is connected!", ready.user.name);
    });

    // 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() {
        println!("Client error: {:?}", why);
    }
}