use anyhow::Context as AnyhowContext;
use solstice_proto::server;

use crate::context::Context;
use crate::control;
use crate::message_handler::MessageHandler;
use crate::room::Message as RoomMessage;

#[derive(Debug, Default)]
pub struct RoomMessageResponseHandler;

impl MessageHandler for RoomMessageResponseHandler {
  type Message = server::RoomMessageResponse;

  fn run(
    self,
    context: &mut Context,
    response: &server::RoomMessageResponse,
  ) -> anyhow::Result<()> {
    let room = context
      .state
      .rooms
      .get_mut_strict(&response.room_name)
      .context("looking up room")?;

    let message = RoomMessage {
      received_at: context.system_clock.now(),
      user_name: response.user_name.clone(),
      message: response.message.clone(),
    };

    room.messages.insert(message.clone());

    context
      .control_response_tx
      .blocking_send(control::Response::RoomMessageResponse(
        control::RoomMessageResponse {
          room_name: response.room_name.clone(),
          message,
        },
      ))
      .context("sending control response")?;
    Ok(())
  }

  fn name() -> String {
    "RoomMessageResponseHandler".to_string()
  }
}

#[cfg(test)]
mod tests {
  use std::time::{Duration, SystemTime};

  use solstice_proto::server;

  use crate::clock::SimulatedSystemClock;
  use crate::context::{ContextBundle, ContextOptions};
  use crate::control;
  use crate::message_handler::MessageHandler;
  use crate::room::{Message, Room, Visibility};

  use super::RoomMessageResponseHandler;

  fn system_time_from_secs(seconds: u64) -> SystemTime {
    SystemTime::UNIX_EPOCH + Duration::from_secs(seconds)
  }

  #[test]
  fn run_forwards_response() {
    let mut options = ContextOptions::default();
    options
      .initial_state
      .rooms
      .insert("apple".to_string(), Room::new(Visibility::Public, 1));
    options.simulated_clock =
      Some(SimulatedSystemClock::new(system_time_from_secs(42)));

    let mut bundle = ContextBundle::new(options);

    RoomMessageResponseHandler::default()
      .run(
        &mut bundle.context,
        &server::RoomMessageResponse {
          room_name: "apple".to_string(),
          user_name: "shruti".to_string(),
          message: "yo!".to_string(),
        },
      )
      .expect("running handler");

    let response = bundle
      .control_response_rx
      .blocking_recv()
      .expect("receiving control response");

    assert_eq!(
      response,
      control::Response::RoomMessageResponse(control::RoomMessageResponse {
        room_name: "apple".to_string(),
        message: Message {
          user_name: "shruti".to_string(),
          message: "yo!".to_string(),
          received_at: SystemTime::UNIX_EPOCH + Duration::from_secs(42),
        },
      })
    );
  }

  #[test]
  fn run_stores_message() {
    let mut room = Room::new(Visibility::Public, 42);
    room.messages.insert(Message {
      received_at: system_time_from_secs(42),
      user_name: "karandeep".to_string(),
      message: "namaste!".to_string(),
    });

    let mut options = ContextOptions::default();
    options
      .initial_state
      .rooms
      .insert("apple".to_string(), room.clone());
    options.simulated_clock =
      Some(SimulatedSystemClock::new(system_time_from_secs(43)));

    let mut bundle = ContextBundle::new(options);

    RoomMessageResponseHandler::default()
      .run(
        &mut bundle.context,
        &server::RoomMessageResponse {
          room_name: "apple".to_string(),
          user_name: "shruti".to_string(),
          message: "yo!".to_string(),
        },
      )
      .expect("running handler");

    let room = bundle
      .context
      .state
      .rooms
      .get_strict("apple")
      .expect("looking up room");

    assert_eq!(
      room.messages.to_vec(),
      vec![
        Message {
          received_at: system_time_from_secs(42),
          user_name: "karandeep".to_string(),
          message: "namaste!".to_string(),
        },
        Message {
          received_at: system_time_from_secs(43),
          user_name: "shruti".to_string(),
          message: "yo!".to_string(),
        },
      ]
    );
  }
}