pub use ck;
use ck::*;

use chrono::Utc;
use ext_calckey_model_migration::{Migrator, MigratorTrait};
use futures_util::StreamExt;
use redis::IntoConnectionInfo;
use sea_orm::ActiveValue::Set;
use sea_orm::{
    ColumnTrait, ConnectOptions, DatabaseConnection, DbErr, EntityTrait, QueryFilter, QueryOrder,
    TransactionTrait,
};
use serde::{Deserialize, Serialize};
use std::future::Future;
use strum::IntoStaticStr;
use thiserror::Error;
use tokio::select;
use tokio_util::sync::CancellationToken;
use tracing::log::LevelFilter;
use tracing::{error, info};

#[derive(Debug)]
pub struct ConnectorConfig {
    pub url: String,
}

#[derive(Clone, Debug)]
pub struct CalckeyModel(DatabaseConnection);

#[derive(Debug, Error, IntoStaticStr)]
pub enum CalckeyDbError {
    #[error("Database error: {0}")]
    DbError(#[from] DbErr),
}

impl CalckeyModel {
    pub async fn new(config: ConnectorConfig) -> Result<Self, CalckeyDbError> {
        let opt = ConnectOptions::new(config.url)
            .max_connections(64)
            .min_connections(8)
            .sqlx_logging(true)
            .sqlx_logging_level(LevelFilter::Debug)
            .to_owned();

        Ok(CalckeyModel(sea_orm::Database::connect(opt).await?))
    }

    pub async fn migrate(&self) -> Result<(), CalckeyDbError> {
        Migrator::up(&self.0, None).await?;

        Ok(())
    }

    pub fn inner(&self) -> &DatabaseConnection {
        &self.0
    }

    pub async fn get_user_by_tag(
        &self,
        name: &str,
        instance: Option<&str>,
    ) -> Result<Option<user::Model>, CalckeyDbError> {
        let name = name.to_lowercase();
        let instance = instance.map(str::to_lowercase);

        let user = if let Some(instance) = instance {
            user::Entity::find()
                .filter(user::Column::UsernameLower.eq(name))
                .filter(user::Column::Host.eq(instance))
        } else {
            user::Entity::find().filter(
                user::Column::UsernameLower
                    .eq(name)
                    .and(user::Column::Host.is_null()),
            )
        }
        .one(&self.0)
        .await?;

        Ok(user)
    }

    pub async fn get_note_by_id(&self, id: &str) -> Result<Option<note::Model>, CalckeyDbError> {
        Ok(note::Entity::find()
            .filter(note::Column::Id.eq(id))
            .one(&self.0)
            .await?)
    }

    pub async fn get_user_by_id(&self, id: &str) -> Result<Option<user::Model>, CalckeyDbError> {
        Ok(user::Entity::find()
            .filter(user::Column::Id.eq(id))
            .one(&self.0)
            .await?)
    }

    pub async fn get_user_by_token(
        &self,
        token: &str,
    ) -> Result<Option<user::Model>, CalckeyDbError> {
        Ok(user::Entity::find()
            .filter(
                user::Column::Token
                    .eq(token)
                    .and(user::Column::Host.is_null()),
            )
            .one(&self.0)
            .await?)
    }

    pub async fn get_user_by_uri(&self, uri: &str) -> Result<Option<user::Model>, CalckeyDbError> {
        Ok(user::Entity::find()
            .filter(user::Column::Uri.eq(uri))
            .one(&self.0)
            .await?)
    }

    pub async fn get_local_emoji(&self) -> Result<Vec<emoji::Model>, CalckeyDbError> {
        Ok(emoji::Entity::find()
            .filter(emoji::Column::Host.is_null())
            .order_by_asc(emoji::Column::Category)
            .order_by_asc(emoji::Column::Name)
            .all(&self.0)
            .await?)
    }

    pub async fn get_access_token(
        &self,
        token: &str,
    ) -> Result<Option<access_token::Model>, CalckeyDbError> {
        let token = access_token::Entity::update(access_token::ActiveModel {
            last_used_at: Set(Some(Utc::now().into())),
            ..Default::default()
        })
        .filter(
            access_token::Column::Token
                .eq(token)
                .or(access_token::Column::Hash.eq(token.to_lowercase())),
        )
        .exec(&self.0)
        .await;

        if let Err(DbErr::RecordNotUpdated) = token {
            return Ok(None);
        }

        Ok(Some(token?))
    }

    pub async fn get_app_by_id(&self, id: &str) -> Result<Option<app::Model>, CalckeyDbError> {
        Ok(app::Entity::find()
            .filter(app::Column::Id.eq(id))
            .one(&self.0)
            .await?)
    }

    pub async fn get_instance_meta(&self) -> Result<meta::Model, CalckeyDbError> {
        let txn = self.0.begin().await?;

        let meta = meta::Entity::find().one(&txn).await?;

        if let Some(meta) = meta {
            txn.commit().await?;
            return Ok(meta);
        }

        let model = meta::ActiveModel {
            id: Set("x".to_string()),
            ..Default::default()
        };

        let meta = meta::Entity::insert(model)
            .exec_with_returning(&txn)
            .await?;

        txn.commit().await?;

        Ok(meta)
    }
}

#[derive(Debug)]
pub struct CacheConnectorConfig {
    pub url: String,
}

#[derive(Clone, Debug)]
pub struct CalckeyCache(redis::Client);

#[derive(Debug, Error, IntoStaticStr)]
pub enum CalckeyCacheError {
    #[error("Redis error: {0}")]
    RedisError(#[from] redis::RedisError),
}

impl CalckeyCache {
    pub fn new(config: CacheConnectorConfig) -> Result<Self, CalckeyCacheError> {
        let conn_info = config.url.into_connection_info()?;

        // TODO: Allow overriding redis config with individual options (maybe)
        let redis_config = redis::ConnectionInfo {
            addr: conn_info.addr,
            redis: conn_info.redis,
        };

        Ok(CalckeyCache(redis::Client::open(redis_config)?))
    }

    pub fn inner(&self) -> &redis::Client {
        &self.0
    }

    pub async fn conn(&self) -> Result<CalckeyCacheClient, CalckeyCacheError> {
        Ok(CalckeyCacheClient(self.0.get_async_connection().await?))
    }
}

pub struct CalckeyCacheClient(redis::aio::Connection);

#[derive(Clone, Debug, Deserialize)]
#[serde(tag = "channel", content = "message")]
pub enum SubMessage {
    Internal(InternalStreamMessage),
    #[serde(other)]
    Other,
}

#[derive(Clone, Debug, Serialize, Deserialize)]
#[serde(tag = "type", content = "body")]
#[serde(rename_all = "camelCase")]
pub enum InternalStreamMessage {
    #[serde(rename_all = "camelCase")]
    UserChangeSuspendedState {
        id: String,
        is_suspended: bool,
    },
    #[serde(rename_all = "camelCase")]
    UserChangeSilencedState {
        id: String,
        is_silenced: bool,
    },
    #[serde(rename_all = "camelCase")]
    UserChangeModeratorState {
        id: String,
        is_moderator: bool,
    },
    #[serde(rename_all = "camelCase")]
    UserTokenRegenerated {
        id: String,
        old_token: String,
        new_token: String,
    },
    LocalUserUpdated {
        id: String,
    },
    RemoteUserUpdated {
        id: String,
    },
    WebhookCreated(webhook::Model),
    WebhookDeleted(webhook::Model),
    WebhookUpdated(webhook::Model),
    AntennaCreated(antenna::Model),
    AntennaDeleted(antenna::Model),
    AntennaUpdated(antenna::Model),
}

impl CalckeyCacheClient {
    pub async fn subscribe<F: Future<Output = ()> + Send + 'static>(
        self,
        prefix: &str,
        handler: impl Fn(SubMessage) -> F + Send + Sync + 'static,
    ) -> Result<CalckeySub, CalckeyCacheError> {
        CalckeySub::new(self.0, prefix, handler).await
    }
}

pub struct CalckeySub(CancellationToken);

impl CalckeySub {
    async fn new<F: Future<Output = ()> + Send + 'static>(
        conn: redis::aio::Connection,
        prefix: &str,
        handler: impl Fn(SubMessage) -> F + Send + Sync + 'static,
    ) -> Result<Self, CalckeyCacheError> {
        let mut pub_sub = conn.into_pubsub();
        pub_sub.subscribe(prefix).await?;

        let token = CancellationToken::new();
        let token_rx = token.clone();
        let prefix = prefix.to_string();

        tokio::spawn(async move {
            let mut on_message = pub_sub.on_message();

            while let Some(msg) = select! {
                msg = on_message.next() => msg,
                _ = token_rx.cancelled() => {
                    drop(on_message);
                    if let Err(e) = pub_sub.unsubscribe(prefix).await {
                        info!("Redis error: {:?}", e);
                    }
                    return;
                }
            } {
                let data = &match msg.get_payload::<String>() {
                    Ok(val) => val,
                    Err(e) => {
                        info!("Redis error: {:?}", e);
                        continue;
                    }
                };

                let parsed = match serde_json::from_str::<SubMessage>(data) {
                    Ok(val) => val,
                    Err(e) => {
                        info!("Message parse error: {:?}", e);
                        continue;
                    }
                };

                println!("Got message: {:#?}", parsed);

                handler(parsed).await;
            }
        });

        Ok(CalckeySub(token))
    }
}

impl Drop for CalckeySub {
    fn drop(&mut self) {
        self.0.cancel();
    }
}