use std::collections::HashMap;

use actix::{Actor, Addr, Context, Handler, Message, Recipient};
use emgauwa_common::db::DbController;
use emgauwa_common::errors::EmgauwaError;
use emgauwa_common::models::{convert_db_list, Controller, Relay};
use emgauwa_common::types::{ControllerWsAction, EmgauwaUid, RelayStates};
use futures::executor::block_on;
use sqlx::{Pool, Sqlite};

use crate::handlers::v1::ws::relays::{RelaysWs, SendRelays};

#[derive(Message)]
#[rtype(result = "Result<(), EmgauwaError>")]
pub struct DisconnectController {
	pub controller_uid: EmgauwaUid,
}

#[derive(Message)]
#[rtype(result = "Result<(), EmgauwaError>")]
pub struct ConnectController {
	pub address: Recipient<ControllerWsAction>,
	pub controller: Controller,
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct UpdateRelayStates {
	pub controller_uid: EmgauwaUid,
	pub relay_states: RelayStates,
}

#[derive(Message)]
#[rtype(result = "Result<Vec<Relay>, EmgauwaError>")]
pub struct GetRelays {}

#[derive(Message)]
#[rtype(result = "Result<(), EmgauwaError>")]
pub struct Action {
	pub controller_uid: EmgauwaUid,
	pub action: ControllerWsAction,
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct ConnectRelayClient {
	pub addr: Addr<RelaysWs>,
}

pub struct AppState {
	pub pool: Pool<Sqlite>,
	pub connected_controllers: HashMap<EmgauwaUid, (Controller, Recipient<ControllerWsAction>)>,
	pub connected_relay_clients: Vec<Addr<RelaysWs>>,
}

impl AppState {
	pub fn new(pool: Pool<Sqlite>) -> AppState {
		AppState {
			pool,
			connected_controllers: HashMap::new(),
			connected_relay_clients: Vec::new(),
		}
	}

	fn get_relays(&self) -> Result<Vec<Relay>, EmgauwaError> {
		let mut pool_conn = block_on(self.pool.acquire())?;
		let db_controllers = block_on(DbController::get_all(&mut pool_conn))?;
		let mut controllers: Vec<Controller> = convert_db_list(&mut pool_conn, db_controllers)?;

		self.connected_controllers
			.iter()
			.for_each(|(uid, (connected_controller, _))| {
				if let Some(c) = controllers.iter_mut().find(|c| c.c.uid == *uid) {
					c.apply_relay_states(&connected_controller.get_relay_states());
				}
			});

		let mut relays: Vec<Relay> = Vec::new();
		controllers.iter().for_each(|c| {
			relays.extend(c.relays.clone());
		});

		Ok(relays)
	}

	fn notify_relay_clients(&mut self) {
		self.connected_relay_clients.retain(|addr| addr.connected());

		match self.get_relays() {
			Ok(relays) => match serde_json::to_string(&relays) {
				Ok(json) => {
					self.connected_relay_clients.iter_mut().for_each(|addr| {
						let relays_json = json.clone();
						addr.do_send(SendRelays { relays_json });
					});
				}
				Err(err) => {
					log::error!("Failed to serialize relays: {:?}", err);
				}
			},
			Err(err) => {
				log::error!("Failed to get relays: {:?}", err);
			}
		};
	}
}

impl Actor for AppState {
	type Context = Context<Self>;
}

impl Handler<DisconnectController> for AppState {
	type Result = Result<(), EmgauwaError>;

	fn handle(&mut self, msg: DisconnectController, _ctx: &mut Self::Context) -> Self::Result {
		let mut pool_conn = block_on(self.pool.acquire())?;

		if let Some((controller, address)) = self.connected_controllers.remove(&msg.controller_uid)
		{
			if let Err(err) = block_on(controller.c.update_active(&mut pool_conn, false)) {
				log::error!(
					"Failed to mark controller {} as inactive: {:?}",
					controller.c.uid,
					err
				);
			}
			// TODO: why does the block_on(send()) version not return? The AppState will be stuck.
			//block_on(address.send(ControllerWsAction::Disconnect))??;
			address.do_send(ControllerWsAction::Disconnect);
		}
		Ok(())
	}
}

impl Handler<ConnectController> for AppState {
	type Result = Result<(), EmgauwaError>;

	fn handle(&mut self, msg: ConnectController, _ctx: &mut Self::Context) -> Self::Result {
		log::debug!("Connecting controller: {}", msg.controller.c.uid);
		self.connected_controllers
			.insert(msg.controller.c.uid.clone(), (msg.controller, msg.address));

		Ok(())
	}
}

impl Handler<UpdateRelayStates> for AppState {
	type Result = ();

	fn handle(&mut self, msg: UpdateRelayStates, _ctx: &mut Self::Context) -> Self::Result {
		if let Some((controller, _)) = self.connected_controllers.get_mut(&msg.controller_uid) {
			controller.apply_relay_states(&msg.relay_states);
		}
		self.notify_relay_clients();
	}
}

impl Handler<GetRelays> for AppState {
	type Result = Result<Vec<Relay>, EmgauwaError>;

	fn handle(&mut self, _msg: GetRelays, _ctx: &mut Self::Context) -> Self::Result {
		self.get_relays()
	}
}

impl Handler<Action> for AppState {
	type Result = Result<(), EmgauwaError>;

	fn handle(&mut self, msg: Action, _ctx: &mut Self::Context) -> Self::Result {
		log::debug!("Forwarding action: {:?}", msg.action);
		if let Some((_, address)) = self.connected_controllers.get(&msg.controller_uid) {
			// TODO: why does the block_on(send()) version not return? The AppState will be stuck.
			//block_on(address.send(msg.action))?
			address.do_send(msg.action);
			Ok(())
		} else {
			Err(EmgauwaError::Connection(msg.controller_uid))
		}
	}
}

impl Handler<ConnectRelayClient> for AppState {
	type Result = ();

	fn handle(&mut self, msg: ConnectRelayClient, _ctx: &mut Self::Context) -> Self::Result {
		self.connected_relay_clients.push(msg.addr);
	}
}