use std::sync::Arc;

use crate::Machine;
use crate::api::{ClientAction, ClientActions, ServerResponse};
use owl::prelude::*;
use owl::{Serialize, get, query};
use rumqttc::AsyncClient;
use sage::PersonaIdentity;

pub fn is_within_80_seconds(time: chrono::DateTime<chrono::Utc>) -> bool {
    let now = chrono::Utc::now();
    now.signed_duration_since(time).num_seconds() <= 80
}

/// Handle herd MQTT
pub async fn handle_mqtt(topic: String, data: Vec<u8>) {
    log::info!("Received client request from {topic}");
    let (client, cat) = topic.split_once('/').unwrap();
    let mac: Model<Machine> = get!(client).unwrap();

    let dec = crate::IDENTITY
        .get()
        .unwrap()
        .decrypt(&data, &mac.read().identity.sign_key().unwrap())
        .unwrap();

    // TODO : check for recency

    match cat {
        "online" => {
            if let Some(online) = crate::ONLINE.get().unwrap().get(client) {
                if !is_within_80_seconds(*online) {
                    log::info!("Device {client} came back ONLINE");
                }
            } else {
                log::info!("Device {client} went ONLINE");
            }
            crate::ONLINE
                .get()
                .unwrap()
                .insert(client.to_string(), chrono::Utc::now());
        }
        "respond" => {
            let resp: ServerResponse = serde_json::from_slice(&dec.payload).unwrap();
            log::info!("Got response {:?}", resp);

            let entry = crate::DISPATCH.get().unwrap().get(&resp.id).unwrap();
            entry.send(resp);
        }
        _ => {}
    }
}

pub struct TaskWaiter {
    pub id: ulid::Ulid,
    pub recv: crossbeam::channel::Receiver<ServerResponse>,
}

impl TaskWaiter {
    pub async fn wait_for(&self, timeout: std::time::Duration) -> Option<ServerResponse> {
        // TODO tokio spawn blocking?
        self.recv.recv_timeout(timeout).ok()
    }
}

/// Send a message to a registered `machine`
pub async fn send_msg(
    client: &AsyncClient,
    machine: &Model<Machine>,
    request: ClientAction,
) -> TaskWaiter {
    let data = serde_json::to_string(&request).unwrap();
    let pk = &machine.read().identity;
    let rec = pk.enc_key().unwrap();
    let machine_id = machine.read().id.to_string().replace("-", "");

    let payload = crate::IDENTITY
        .get()
        .unwrap()
        .encrypt(data.as_bytes(), &rec);
    let topic = format!("{machine_id}/cmd");

    client
        .publish(topic, rumqttc::QoS::AtMostOnce, true, payload)
        .await
        .unwrap();

    let (sender, recv) = tokio::sync::mpsc::channel(100);
    crate::DISPATCH.get().unwrap().insert(request.id, sender);

    TaskWaiter {
        id: request.id,
        recv,
    }
}

/// Subscribe to all `device->server` topics
pub async fn listen_to_device(client: &AsyncClient, machine_id: &str) {
    // Online Presence
    client
        .subscribe(format!("{machine_id}/online"), rumqttc::QoS::AtMostOnce)
        .await
        .unwrap();
    client
        .subscribe(format!("{machine_id}/respond"), rumqttc::QoS::AtMostOnce)
        .await
        .unwrap();
}

/// Subscibe to incoming messages from all registered machines
pub async fn listen_to_devices(client: &AsyncClient) {
    let machines: Vec<Model<Machine>> = query!(|_| true);
    for machine in machines {
        let machine_id = machine.read().id.to_string();
        let machine_id = machine_id.trim().replace("-", "");
        log::info!("Sub to {machine_id}");

        listen_to_device(client, &machine_id).await;
    }
}