use config::ai::AiConfig;
use models::users::user::{self, ProfileVisibility};
use sea_orm::{ActiveModelTrait, ColumnTrait, DatabaseConnection, EntityTrait, QueryFilter, Set};
use time::OffsetDateTime;
use uuid::Uuid;

/// 解析（必要时创建）AI 系统用户。
///
/// 该用户以 `bot=true, system=true` 标记，无口令、不可登录，仅用于承载
/// AI 评审与评论的作者身份。
pub async fn resolve_bot_user(
    db: &DatabaseConnection,
    cfg: &AiConfig,
) -> Result<Uuid, sea_orm::DbErr> {
    let username = cfg.bot_username.trim();
    let lower = username.to_lowercase();
    if let Some(row) = user::Entity::find()
        .filter(user::Column::LowerName.eq(&lower))
        .one(db)
        .await?
    {
        return Ok(row.uid);
    }
    let uid = Uuid::now_v7();
    let now = OffsetDateTime::now_utc();
    let created = user::ActiveModel {
        uid: Set(uid),
        username: Set(username.to_string()),
        lower_name: Set(lower.clone()),
        display_name: Set(cfg.bot_display_name.trim().to_string()),
        avatar_url: Set(String::new()),
        is_active: Set(true),
        is_restricted: Set(false),
        prohibit_login: Set(true),
        visibility: Set(ProfileVisibility::Public),
        bot: Set(true),
        system: Set(true),
        last_login_at: Set(None),
        last_login_ip_hash: Set(None),
        version: Set(1),
        passwd_hash: Set(None),
        password_last_changed_at: Set(None),
        passwd_version: Set(None),
        totp_encrypted_secret: Set(None),
        totp_enabled: Set(false),
        totp_last_used_at: Set(None),
        totp_last_counter: Set(None),
        timezone: Set(None),
        locale: Set(None),
        language: Set(None),
        created_at: Set(now),
        updated_at: Set(now),
    }
    .insert(db)
    .await;
    match created {
        Ok(row) => Ok(row.uid),
        // 并发创建时另一进程已插入，回查即可。
        Err(_) => user::Entity::find()
            .filter(user::Column::LowerName.eq(&lower))
            .one(db)
            .await?
            .map(|row| row.uid)
            .ok_or_else(|| sea_orm::DbErr::RecordNotFound("ai bot user".to_string())),
    }
}