use std::env;

use rand::Rng;

use iota_streams::{
    core::{println, psk::Psk, Result},
    app::{
        transport::{
            tangle::client::{
                Client,
            },
        },
    },
    app_channels::api::{
        pskid_from_psk,
        ChannelType,
        tangle::{
            Author, Bytes, Subscriber, MessageContent, UnwrappedMessage
        },
    },
};

#[tokio::main]
async fn main() -> Result<()> {
    let node_url = env::var("URL").unwrap_or_else(|_| "https://api.lb-0.testnet.chrysalis2.com:443".to_string());

    let mut client = Client::new_from_url(&node_url);

    let alph9 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ9";
    // Generate a unique seed for the author
    let seed: &str = &(0..10)
        .map(|_| alph9.chars().nth(rand::thread_rng().gen_range(0, 27)).unwrap())
        .collect::<String>();

    
    // generate presharedkey
    let presharedkey = rand::thread_rng().gen::<[u8; 32]>();

    let mut author = Author::new(seed, ChannelType::MultiBranch, client.clone());

    println!("\nAnnounce Channel");
    // Create the channel with an announcement message. Make sure to save the resulting link somewhere,
    let announcement_link = author.send_announce()?;
    println!("Announcement Link: {}", &announcement_link);

    let psk = Psk::clone_from_slice(&presharedkey);
    let pskid = pskid_from_psk(&psk);
    author.store_psk(pskid.clone(), psk.clone());

    // author sends keyload using preshared key
    let (_keyload_link, keyload_seq_link) = author.send_keyload(&announcement_link, 
        &[pskid.clone()],
        &vec![])?;
    println!("Sent Keyload for Sub A: {}, seq: {:?}", _keyload_link, &keyload_seq_link);

    // author sends package
    let (signed_msg_link, signed_seq_link) = author.send_signed_packet(&announcement_link, 
        &Bytes("".as_bytes().to_vec()),
        &Bytes("message from the grand author".as_bytes().to_vec()))?;
    
    println!("Sent msg from Sub author: {}, seq: {:?}", signed_msg_link, signed_seq_link);

    // In their own separate instances generate the subscriber(s) that will be attaching to the channel
    let mut subscriber_a = Subscriber::new("SubscriberA", client.clone());
    // Receive the announcement message to start listening to the channel
    subscriber_a.receive_announcement(&announcement_link)?;
    // subscriber stores psk
    subscriber_a.store_psk(pskid.clone(), psk.clone());

    // A new subscriber SubscriberB is added and sends a signed_packet to his branch
    let mut subscriber_b = Subscriber::new("SubscriberB", client.clone());
    subscriber_b.receive_announcement(&announcement_link)?;

    let subscribe_msg_b = subscriber_b.send_subscribe(&announcement_link)?;
    let sub_b_pk = subscriber_b.get_pk();

    author.receive_subscribe(&subscribe_msg_b)?;

    let (_keyload_2_link, keyload_2_seq_link) = author.send_keyload(&announcement_link, 
        &[pskid.clone()], 
        &vec![sub_b_pk.clone()])?;
    println!("Sent Keyload for Sub B: {}, seq: {:?}", _keyload_2_link.clone(), keyload_2_seq_link);
    subscriber_b.sync_state();

    let prev_msg_link = _keyload_2_link;
    let message = "very basic message from b";

    let (res_signed_package_b_link, res_signed_package_b_seq_link) = 
        subscriber_b.send_signed_packet(&prev_msg_link, 
            &Bytes("ssw".as_bytes().to_vec()), 
            &Bytes(message.as_bytes().to_vec()))?;

    println!("Sent msg from Sub B: {}, seq: {:?}", res_signed_package_b_link, res_signed_package_b_seq_link);

    print("Sub A", subscriber_a.fetch_all_next_msgs());

    print("Sub B", subscriber_b.fetch_all_next_msgs());

    print("Author", author.fetch_all_next_msgs());
    
    Ok(())
}

fn print(name: &str, msg: Vec<UnwrappedMessage>) {
    for r in msg {
        let content = &r.body;
        match content {
            MessageContent::SignedPacket {
                pk: _,
                public_payload,
                masked_payload,
            } => {
                println!("Received message for: {}", name);
                println!("public: {}", String::from_utf8(public_payload.0.to_vec()).unwrap());
                println!("masked: {}", String::from_utf8(masked_payload.0.to_vec()).unwrap())
            },
            _ => println!("Received message for: {}, {:?}", name, content),
        };

        //let details = client.get_link_details(&r.link)?;
        println!("prev link: {}", &r.prev_link);
        println!("link: {}", &r.link);
        //println!("id: {}\n", details.metadata.message_id);
    };
}