use models::pull_request::{pull_request_label, pull_requests};
use sea_orm::ActiveValue::Set;
use sea_orm::{
    ActiveModelTrait, ColumnTrait, EntityTrait, QueryFilter, QueryOrder, TransactionTrait,
};
use serde::Deserialize;
use utoipa::ToSchema;
use uuid::Uuid;

use crate::errors::PullError;
use crate::services::events::{EVENT_LABELED, EVENT_UNLABELED};
use crate::services::service::PullService;
use crate::share::authz;

#[derive(Debug, Clone, Deserialize, ToSchema)]
pub struct AttachLabelCmd {
    /// 标签 UUID 或名称（同一仓库目录内的标签）。
    pub label: String,
}

impl PullService {
    async fn resolve_label(
        &self,
        space_id: Uuid,
        reference: &str,
    ) -> Result<issues::services::labels::LabelDto, PullError> {
        Ok(self.issues.resolve_space_label(space_id, reference).await?)
    }
    pub async fn list_label_options(
        &self,
        space_id: Uuid,
    ) -> Result<Vec<issues::services::labels::LabelDto>, PullError> {
        Ok(self.issues.space_labels(space_id).await?)
    }
    pub async fn list_labels(
        &self,
        pull_id: Uuid,
    ) -> Result<Vec<issues::services::labels::LabelDto>, PullError> {
        let links = pull_request_label::Entity::find()
            .filter(pull_request_label::Column::PullRequestId.eq(pull_id))
            .order_by_asc(pull_request_label::Column::CreatedAt)
            .all(self.db_read())
            .await?;
        if links.is_empty() {
            return Ok(Vec::new());
        }
        let ids: Vec<Uuid> = links.iter().map(|link| link.label_id).collect();
        Ok(self.issues.labels_by_ids(ids).await?)
    }

    pub async fn attach_label(
        &self,
        pull: &pull_requests::Model,
        space_id: Uuid,
        caller: i64,
        cmd: AttachLabelCmd,
    ) -> Result<Vec<issues::services::labels::LabelDto>, PullError> {
        authz::require_unlocked(pull)?;
        let label = self.resolve_label(space_id, &cmd.label).await?;
        let existing = pull_request_label::Entity::find()
            .filter(pull_request_label::Column::PullRequestId.eq(pull.id))
            .filter(pull_request_label::Column::LabelId.eq(label.id))
            .one(self.db_read())
            .await?;
        if existing.is_none() {
            let event_pull = pull.clone();
            let this = self.clone();
            self.db_write()
                .transaction::<_, (), PullError>(move |tx| {
                    Box::pin(async move {
                        pull_request_label::ActiveModel {
                            id: Set(Uuid::now_v7()),
                            pull_request_id: Set(event_pull.id),
                            label_id: Set(label.id),
                            created_at: Set(OffsetDateTime::now_utc()),
                        }
                        .insert(tx)
                        .await?;
                        this.record_event_with(
                            tx,
                            &event_pull,
                            Some(caller),
                            EVENT_LABELED,
                            None,
                            Some(label.name),
                        )
                        .await?;
                        Ok(())
                    })
                })
                .await?;
        }
        self.list_labels(pull.id).await
    }

    pub async fn detach_label(
        &self,
        pull: &pull_requests::Model,
        dir_id: Uuid,
        caller: i64,
        label_ref: &str,
    ) -> Result<Vec<issues::services::labels::LabelDto>, PullError> {
        authz::require_unlocked(pull)?;
        let label = self.resolve_label(dir_id, label_ref).await?;
        let event_pull = pull.clone();
        let this = self.clone();
        self.db_write()
            .transaction::<_, (), PullError>(move |tx| {
                Box::pin(async move {
                    let deleted = pull_request_label::Entity::delete_many()
                        .filter(pull_request_label::Column::PullRequestId.eq(event_pull.id))
                        .filter(pull_request_label::Column::LabelId.eq(label.id))
                        .exec(tx)
                        .await?;
                    if deleted.rows_affected > 0 {
                        this.record_event_with(
                            tx,
                            &event_pull,
                            Some(caller),
                            EVENT_UNLABELED,
                            None,
                            Some(label.name),
                        )
                        .await?;
                    }
                    Ok(())
                })
            })
            .await?;
        self.list_labels(pull.id).await
    }
}

use time::OffsetDateTime;