//! Ensures the built-in alternative display currencies always exist.
//!
//! EUR is the base currency and is never stored. For now the only alternative is
//! the Czech koruna (CZK); the admin sets its exchange rate and can disable it.
//! We insert each one only when its `code` is missing, so an admin's rate/enabled
//! changes are never overwritten on the next boot.

use async_trait::async_trait;
use loco_rs::prelude::*;
use sea_orm::{ActiveModelTrait, ColumnTrait, EntityTrait, PaginatorTrait, QueryFilter, Set};

use crate::models::currencies;
use crate::shared::currency::SCALE;

/// `(code, symbol, default_rate_e4)` — default rate is a placeholder the admin
/// is expected to update from the live FX rate.
const BUILTINS: [(&str, &str, i64); 1] = [("CZK", "Kč", 25 * SCALE)];

pub struct CurrencySeeder;

#[async_trait]
impl Initializer for CurrencySeeder {
    fn name(&self) -> String {
        "currency-seeder".to_string()
    }

    async fn before_run(&self, ctx: &AppContext) -> Result<()> {
        for (code, symbol, rate_e4) in BUILTINS {
            let exists = currencies::Entity::find()
                .filter(currencies::Column::Code.eq(code))
                .count(&ctx.db)
                .await?
                > 0;
            if exists {
                continue;
            }
            currencies::ActiveModel {
                code: Set(code.to_string()),
                symbol: Set(symbol.to_string()),
                rate_e4: Set(rate_e4),
                enabled: Set(true),
                ..Default::default()
            }
            .insert(&ctx.db)
            .await?;
            tracing::info!(currency = code, "seeded display currency");
        }
        Ok(())
    }
}