use async_graphql::SimpleObject;
use async_trait::async_trait;
use sea_orm::{
    ActiveValue, Condition, FromJsonQueryResult, FromQueryResult, IntoSimpleExpr, JoinType,
    QuerySelect,
    entity::prelude::*,
    sea_query::{Alias, IntoCondition, OnConflict},
};
use serde::{Deserialize, Serialize};

use super::subscription_bangumi;
use crate::{
    app::AppContextTrait,
    errors::RecorderResult,
    extract::{
        mikan::{
            MikanBangumiHash, MikanBangumiMeta, build_mikan_bangumi_subscription_rss_url,
            scrape_mikan_poster_meta_from_image_url,
        },
        origin::{OriginCompTrait, SeasonComp},
    },
};

#[derive(
    Clone, Debug, PartialEq, Eq, Serialize, Deserialize, FromJsonQueryResult, SimpleObject,
)]
pub struct BangumiFilter {
    pub name: Option<Vec<String>>,
    pub group: Option<Vec<String>>,
}

#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, EnumIter, DeriveActiveEnum)]
#[sea_orm(rs_type = "String", db_type = "Enum", enum_name = "bangumi_type")]
pub enum BangumiType {
    #[sea_orm(string_value = "mikan")]
    Mikan,
}

#[derive(Clone, Debug, PartialEq, DeriveEntityModel, Eq, Serialize, Deserialize)]
#[sea_orm(table_name = "bangumi")]
pub struct Model {
    #[sea_orm(default_expr = "Expr::current_timestamp()")]
    pub created_at: DateTimeUtc,
    #[sea_orm(default_expr = "Expr::current_timestamp()")]
    pub updated_at: DateTimeUtc,
    #[sea_orm(primary_key)]
    pub id: i32,
    pub mikan_bangumi_id: Option<String>,
    pub bangumi_type: BangumiType,
    pub subscriber_id: i32,
    pub display_name: String,
    pub origin_name: String,
    pub season: i32,
    pub season_raw: Option<String>,
    pub fansub: Option<String>,
    pub mikan_fansub_id: Option<String>,
    pub filter: Option<BangumiFilter>,
    pub rss_link: Option<String>,
    pub poster_link: Option<String>,
    pub origin_poster_link: Option<String>,
    pub homepage: Option<String>,
}

#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
pub enum Relation {
    #[sea_orm(has_many = "super::subscriptions::Entity")]
    Subscription,
    #[sea_orm(
        belongs_to = "super::subscribers::Entity",
        from = "Column::SubscriberId",
        to = "super::subscribers::Column::Id",
        on_update = "Cascade",
        on_delete = "Cascade"
    )]
    Subscriber,
    #[sea_orm(has_many = "super::episodes::Entity")]
    Episode,
    #[sea_orm(has_many = "super::subscription_bangumi::Entity")]
    SubscriptionBangumi,
}

impl Related<super::episodes::Entity> for Entity {
    fn to() -> RelationDef {
        Relation::Episode.def()
    }
}

impl Related<super::subscription_bangumi::Entity> for Entity {
    fn to() -> RelationDef {
        Relation::SubscriptionBangumi.def()
    }
}

impl Related<super::subscriptions::Entity> for Entity {
    fn to() -> RelationDef {
        super::subscription_bangumi::Relation::Subscription.def()
    }

    fn via() -> Option<RelationDef> {
        Some(super::subscription_bangumi::Relation::Bangumi.def().rev())
    }
}

impl Related<super::subscribers::Entity> for Entity {
    fn to() -> RelationDef {
        Relation::Subscriber.def()
    }
}

#[derive(Copy, Clone, Debug, EnumIter, DeriveRelatedEntity)]
pub enum RelatedEntity {
    #[sea_orm(entity = "super::subscriptions::Entity")]
    Subscription,
    #[sea_orm(entity = "super::subscribers::Entity")]
    Subscriber,
    #[sea_orm(entity = "super::episodes::Entity")]
    Episode,
    #[sea_orm(entity = "super::subscription_bangumi::Entity")]
    SubscriptionBangumi,
}

impl ActiveModel {
    #[tracing::instrument(err, skip_all, fields(mikan_bangumi_id = %meta.mikan_bangumi_id, mikan_fansub_id = %meta.mikan_fansub_id, subscriber_id = %subscriber_id))]
    pub async fn from_mikan_bangumi_meta(
        ctx: &dyn AppContextTrait,
        meta: MikanBangumiMeta,
        subscriber_id: i32,
        _subscription_id: i32,
    ) -> RecorderResult<Self> {
        let mikan_client = ctx.mikan();
        let mikan_base_url = mikan_client.base_url();
        let season_comp = SeasonComp::parse_comp(&meta.bangumi_title)
            .ok()
            .map(|(_, s)| s);
        let season_index = season_comp.as_ref().map(|s| s.num).unwrap_or(1);
        let season_raw = season_comp.map(|s| s.source.into_owned());

        let rss_url = build_mikan_bangumi_subscription_rss_url(
            mikan_base_url.clone(),
            &meta.mikan_bangumi_id,
            Some(&meta.mikan_fansub_id),
        );

        let poster_link = if let Some(origin_poster_src) = meta.origin_poster_src.clone() {
            let poster_meta =
                scrape_mikan_poster_meta_from_image_url(ctx, origin_poster_src).await?;
            poster_meta.poster_src
        } else {
            None
        };

        Ok(Self {
            mikan_bangumi_id: ActiveValue::Set(Some(meta.mikan_bangumi_id)),
            mikan_fansub_id: ActiveValue::Set(Some(meta.mikan_fansub_id)),
            subscriber_id: ActiveValue::Set(subscriber_id),
            display_name: ActiveValue::Set(meta.bangumi_title.clone()),
            origin_name: ActiveValue::Set(meta.bangumi_title),
            season: ActiveValue::Set(season_index),
            season_raw: ActiveValue::Set(season_raw),
            fansub: ActiveValue::Set(Some(meta.fansub)),
            poster_link: ActiveValue::Set(poster_link),
            origin_poster_link: ActiveValue::Set(meta.origin_poster_src.map(|src| src.to_string())),
            homepage: ActiveValue::Set(Some(meta.homepage.to_string())),
            rss_link: ActiveValue::Set(Some(rss_url.to_string())),
            ..Default::default()
        })
    }
}

#[async_trait]
impl ActiveModelBehavior for ActiveModel {}

impl Model {
    pub async fn get_or_insert_from_mikan<F>(
        ctx: &dyn AppContextTrait,
        hash: MikanBangumiHash,
        subscriber_id: i32,
        subscription_id: i32,
        create_bangumi_fn: F,
    ) -> RecorderResult<Self>
    where
        F: AsyncFnOnce() -> RecorderResult<ActiveModel>,
    {
        #[derive(FromQueryResult)]
        struct ModelWithIsSubscribed {
            #[sea_orm(nested)]
            bangumi: Model,
            is_subscribed: bool,
        }

        let db = ctx.db();

        let subscription_bangumi_alias = Alias::new("sb");
        let mut is_subscribed = false;
        let new_bangumi_model = if let Some(existed) = Entity::find()
            .filter(
                Condition::all()
                    .add(Column::MikanBangumiId.eq(Some(hash.mikan_bangumi_id)))
                    .add(Column::MikanFansubId.eq(Some(hash.mikan_fansub_id)))
                    .add(Column::SubscriberId.eq(subscriber_id)),
            )
            .column_as(
                Expr::col((
                    subscription_bangumi_alias.clone(),
                    subscription_bangumi::Column::SubscriptionId,
                ))
                .is_not_null(),
                "is_subscribed",
            )
            .join_as_rev(
                JoinType::LeftJoin,
                subscription_bangumi::Relation::Bangumi
                    .def()
                    .on_condition(move |left, _right| {
                        Expr::col((left, subscription_bangumi::Column::SubscriptionId))
                            .eq(subscription_id)
                            .into_condition()
                    }),
                subscription_bangumi_alias.clone(),
            )
            .into_model::<ModelWithIsSubscribed>()
            .one(db)
            .await?
        {
            is_subscribed = existed.is_subscribed;
            existed.bangumi
        } else {
            let new_bangumi_active_model = create_bangumi_fn().await?;

            Entity::insert(new_bangumi_active_model)
                .on_conflict(
                    OnConflict::columns([
                        Column::MikanBangumiId,
                        Column::MikanFansubId,
                        Column::SubscriberId,
                    ])
                    .update_columns([
                        Column::OriginName,
                        Column::Fansub,
                        Column::PosterLink,
                        Column::OriginPosterLink,
                        Column::Season,
                        Column::SeasonRaw,
                        Column::RssLink,
                        Column::Homepage,
                    ])
                    .to_owned(),
                )
                .exec_with_returning(db)
                .await?
        };
        if !is_subscribed {
            subscription_bangumi::Entity::insert(subscription_bangumi::ActiveModel {
                subscription_id: ActiveValue::Set(subscription_id),
                bangumi_id: ActiveValue::Set(new_bangumi_model.id),
                subscriber_id: ActiveValue::Set(subscriber_id),
                ..Default::default()
            })
            .on_conflict(
                OnConflict::columns([
                    subscription_bangumi::Column::SubscriptionId,
                    subscription_bangumi::Column::BangumiId,
                ])
                .do_nothing()
                .to_owned(),
            )
            .exec_without_returning(db)
            .await?;
        }
        Ok(new_bangumi_model)
    }

    pub async fn get_existed_mikan_bangumi_list(
        ctx: &dyn AppContextTrait,
        hashes: impl Iterator<Item = MikanBangumiHash>,
        subscriber_id: i32,
        _subscription_id: i32,
    ) -> RecorderResult<impl Iterator<Item = (i32, MikanBangumiHash)>> {
        Ok(Entity::find()
            .select_only()
            .column(Column::Id)
            .column(Column::MikanBangumiId)
            .column(Column::MikanFansubId)
            .filter(
                Expr::tuple([
                    Column::MikanBangumiId.into_simple_expr(),
                    Column::MikanFansubId.into_simple_expr(),
                    Column::SubscriberId.into_simple_expr(),
                ])
                .in_tuples(hashes.map(|hash| {
                    (
                        hash.mikan_bangumi_id.clone(),
                        hash.mikan_fansub_id.clone(),
                        subscriber_id,
                    )
                })),
            )
            .into_tuple::<(i32, String, String)>()
            .all(ctx.db())
            .await?
            .into_iter()
            .map(|(bangumi_id, mikan_bangumi_id, mikan_fansub_id)| {
                (
                    bangumi_id,
                    MikanBangumiHash {
                        mikan_bangumi_id,
                        mikan_fansub_id,
                    },
                )
            }))
    }

    pub async fn get_subsribed_bangumi_list_from_subscription(
        ctx: &dyn AppContextTrait,
        subscription_id: i32,
    ) -> RecorderResult<Vec<Self>> {
        let db = ctx.db();
        let bangumi_list = Entity::find()
            .filter(
                Condition::all()
                    .add(subscription_bangumi::Column::SubscriptionId.eq(subscription_id)),
            )
            .join_rev(
                JoinType::InnerJoin,
                subscription_bangumi::Relation::Bangumi.def(),
            )
            .all(db)
            .await?;

        Ok(bangumi_list)
    }
}