use std::{
    cell::RefCell,
    collections::HashMap,
    fmt::{Debug, Formatter},
    rc::Rc,
};

use async_trait::async_trait;
use futures::future::{join, join_all};
use matrix_sdk::{ruma::OwnedRoomId, RoomState as MatrixRoomState};
use tracing::{debug, debug_span, error, instrument, trace};

use super::{
    common::{Avatar, UserId},
    messaging_interface::{RoomMessagingConsumerInterface, RoomMessagingProviderInterface},
    room_member::RoomMember,
    space::SpaceId,
    store_interface::{RoomStoreConsumerInterface, RoomStoreProviderInterface},
};
use crate::infrastructure::services::mozaik_builder::create_mozaik;

pub type RoomId = OwnedRoomId;

#[derive(Clone, PartialEq)]
pub struct Invitation {
    invitee_id: UserId,
    sender_id: UserId,
    is_account_user: bool,
}

impl Invitation {
    pub fn new(invitee_id: UserId, sender_id: UserId, is_account_user: bool) -> Self {
        Self {
            invitee_id,
            sender_id,
            is_account_user,
        }
    }

    pub fn is_account_user(&self) -> bool {
        self.is_account_user
    }
}

impl Debug for Invitation {
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), std::fmt::Error> {
        f.debug_tuple("Invitation")
            .field(&self.invitee_id)
            .field(&self.sender_id)
            .field(&self.is_account_user)
            .finish()
    }
}

pub struct Room {
    id: RoomId,

    name: RefCell<Option<String>>,
    topic: Option<String>,
    is_direct: Option<bool>,
    state: Option<MatrixRoomState>,
    avatar: RefCell<Option<Avatar>>,

    invitations: RefCell<HashMap<UserId, Invitation>>,
    members: RefCell<HashMap<UserId, RoomMember>>,

    spaces: Vec<SpaceId>,

    messaging_provider: Option<Rc<dyn RoomMessagingProviderInterface>>,
    store: RefCell<Option<Rc<dyn RoomStoreProviderInterface>>>,
}

impl PartialEq for Room {
    fn eq(&self, other: &Self) -> bool {
        self.id == other.id
    }
}

impl Room {
    pub fn new(
        id: RoomId,
        // TODO: move space at the end of the list of params
        name: Option<String>,
        topic: Option<String>,
        is_direct: Option<bool>,
        state: Option<MatrixRoomState>,
        spaces: Vec<SpaceId>,
    ) -> Self {
        Self {
            id,

            name: RefCell::new(name),
            topic,
            is_direct,
            state,
            avatar: RefCell::new(None),
            invitations: RefCell::new(HashMap::new()),
            members: RefCell::new(HashMap::new()),
            spaces,

            messaging_provider: None,
            store: RefCell::new(None),
        }
    }

    pub fn set_messaging_provider(
        &mut self,
        messaging_provider: Rc<dyn RoomMessagingProviderInterface>,
    ) {
        self.messaging_provider = Some(messaging_provider);
    }

    pub fn set_store(&self, store: Rc<dyn RoomStoreProviderInterface>) {
        *self.store.borrow_mut() = Some(store);
    }

    pub fn id(&self) -> &RoomId {
        &self.id
    }

    #[allow(dead_code)]
    pub fn name(&self) -> Option<String> {
        self.name.borrow().clone()
    }

    #[allow(dead_code)]
    pub fn set_topic(&mut self, topic: Option<String>) {
        self.topic = topic;
    }

    #[allow(dead_code)]
    pub fn state(&self) -> &Option<MatrixRoomState> {
        &self.state
    }

    #[allow(dead_code)]
    pub fn is_invited(&self) -> Option<bool> {
        self.state.map(|state| state == MatrixRoomState::Invited)
    }

    #[instrument(name = "Room", skip_all)]
    fn add_invitation(&self, invitation: Invitation) {
        self.members.borrow_mut().remove(&invitation.invitee_id);

        self.invitations
            .borrow_mut()
            .insert(invitation.invitee_id.clone(), invitation.clone());

        if let Some(store) = self.store.borrow().as_ref() {
            store.on_invitation(invitation);
        }
    }

    #[instrument(name = "Room", skip_all)]
    fn add_member(&self, member: RoomMember) {
        let mut members = self.members.borrow_mut();

        members.insert(member.id().clone(), member.clone());

        // USe the member display name to name the room if it's direct and has no name set.
        if self.name.borrow().is_none() && members.len() == 1 {
            if let Some(member_display_name) = member.display_name() {
                let name = Some(member_display_name.clone());

                self.name.borrow_mut().clone_from(&name);

                if let Some(store) = self.store.borrow().as_ref() {
                    store.on_new_name(name);
                }
            }
        }

        if let Some(store) = self.store.borrow().as_ref() {
            store.on_new_member(member);
        }
    }

    pub async fn get_avatar(&self) -> Option<Avatar> {
        if self.avatar.borrow().is_none() {
            if let Some(requester) = &self.messaging_provider {
                let resp = requester.get_avatar(&self.id).await;
                if let Ok(avatar) = resp {
                    if let Some(avatar) = avatar {
                        return Some(avatar);
                    } else {
                        debug!("The room has no avatar... let's generate one");
                        match self.gen_room_avatar_with_members().await {
                            Ok(avatar) => {
                                if let Some(avatar) = avatar {
                                    return Some(avatar);
                                }
                            }
                            Err(err) => {
                                error!("err={}", err);
                            }
                        }
                    }
                } else {
                    error!("err={:?}", resp);
                }
            }
        }
        self.avatar.borrow().clone()
    }

    #[instrument(name = "Room", skip_all)]
    async fn gen_room_avatar_with_members(&self) -> anyhow::Result<Option<Avatar>> {
        let mut account_member = None::<&RoomMember>;
        let mut other_members = Vec::<&RoomMember>::new();

        let members = self.members.borrow();
        for member in members.values() {
            if member.is_account_user() {
                account_member = Some(member);
            } else {
                other_members.push(member);
            }
        }

        let other_avatars_futures =
            join_all(other_members.iter().map(|member| member.get_avatar()));

        let (other_avatars, account_avatar) = if let Some(account_member) = account_member {
            join(other_avatars_futures, account_member.get_avatar()).await
        } else {
            (
                join_all(other_members.iter().map(|member| member.get_avatar())).await,
                None,
            )
        };

        let other_avatars: Vec<Vec<u8>> = other_avatars.into_iter().flatten().collect();

        if account_avatar.is_some() || !other_avatars.is_empty() {
            let _guard = debug_span!("AvatarRendering").entered();
            Ok(Some(
                create_mozaik(256, 256, other_avatars, account_avatar).await,
            ))
        } else {
            Ok(None)
        }
    }
}

#[async_trait(?Send)]
impl RoomMessagingConsumerInterface for Room {
    #[instrument(name = "Room", skip_all)]
    async fn on_invitation(&self, invitation: Invitation) {
        trace!("on_invitation");
        let sender_id = invitation.sender_id.clone();

        self.add_invitation(invitation);

        if self.is_direct.unwrap_or(false) {
            debug!("1to1 conversation, using the {} avatar", &sender_id);
            if let Ok(avatar) = self.gen_room_avatar_with_members().await {
                debug!("Avatar successfully generated");
                self.avatar.borrow_mut().clone_from(&avatar);
                if let Some(store) = self.store.borrow().as_ref() {
                    store.on_new_avatar(avatar);
                }
            }
        }
    }

    #[instrument(name = "Room", skip_all)]
    async fn on_membership(&self, member: RoomMember) {
        trace!("on_membership");
        self.add_member(member);
    }

    #[instrument(name = "Room", skip_all)]
    async fn on_new_topic(&self, _topic: Option<String>) {
        trace!("on_new_topic");
    }

    #[instrument(name = "Room", skip_all)]
    async fn on_new_name(&self, _name: Option<String>) {
        trace!("on_new_name");
    }

    #[instrument(name = "Room", skip_all)]
    async fn on_new_avatar(&self, avatar: Option<Avatar>) {
        trace!("on_new_avatar");
        self.avatar.borrow_mut().clone_from(&avatar);
        if let Some(store) = self.store.borrow().as_ref() {
            store.on_new_avatar(avatar);
        }
    }
}

#[async_trait(?Send)]
impl RoomStoreConsumerInterface for Room {
    fn id(&self) -> &RoomId {
        &self.id
    }

    fn is_direct(&self) -> Option<bool> {
        self.is_direct
    }

    fn name(&self) -> Option<String> {
        self.name.borrow().clone()
    }

    fn topic(&self) -> Option<String> {
        self.topic.clone()
    }

    async fn avatar(&self) -> Option<Avatar> {
        self.get_avatar().await
    }

    fn spaces(&self) -> &Vec<SpaceId> {
        &self.spaces
    }

    async fn join(&self) {
        if let Some(messaging_provider) = &self.messaging_provider {
            let _ = messaging_provider.join(&self.id).await;
        }
    }
}