use actix::Message;
use model::{ProductId, Quantity, QuantityUnit, Stock, StockId};
use sqlx::PgPool;

use crate::{MultiLoad, Result};

#[derive(Debug, thiserror::Error)]
pub enum Error {
    #[error("Unable to load all stocks")]
    All,
    #[error("Unable to create stock")]
    Create,
    #[error("Unable to update stock")]
    Update,
    #[error("Unable to delete stock")]
    Delete,
    #[error("Unable find stock for product")]
    ProductStock,
}

#[derive(Message)]
#[rtype(result = "Result<Vec<model::Stock>>")]
pub struct AllStocks;

crate::db_async_handler!(AllStocks, all_stocks, Vec<Stock>);

async fn all_stocks(_msg: AllStocks, pool: PgPool) -> Result<Vec<model::Stock>> {
    sqlx::query_as(
        r#"
SELECT id, product_id, quantity, quantity_unit
FROM stocks
    "#,
    )
    .fetch_all(&pool)
    .await
    .map_err(|e| {
        log::error!("{e:?}");
        crate::Error::Stock(Error::All)
    })
}

#[derive(Message)]
#[rtype(result = "Result<model::Stock>")]
pub struct CreateStock {
    pub product_id: ProductId,
    pub quantity: Quantity,
    pub quantity_unit: QuantityUnit,
}

crate::db_async_handler!(CreateStock, create_stock, Stock);

async fn create_stock(msg: CreateStock, pool: PgPool) -> Result<model::Stock> {
    sqlx::query_as(
        r#"
INSERT INTO stocks (product_id, quantity, quantity_unit)
VALUES ($1, $2, $3)
RETURNING id, product_id, quantity, quantity_unit
    "#,
    )
    .bind(msg.product_id)
    .bind(msg.quantity)
    .bind(msg.quantity_unit)
    .fetch_one(&pool)
    .await
    .map_err(|e| {
        log::error!("{e:?}");
        crate::Error::Stock(Error::Create)
    })
}

#[derive(Message)]
#[rtype(result = "Result<model::Stock>")]
pub struct UpdateStock {
    pub id: StockId,
    pub product_id: ProductId,
    pub quantity: Quantity,
    pub quantity_unit: QuantityUnit,
}

crate::db_async_handler!(UpdateStock, update_stock, Stock);

async fn update_stock(msg: UpdateStock, pool: PgPool) -> Result<model::Stock> {
    sqlx::query_as(
        r#"
UPDATE stocks
SET product_id = $1 AND
    quantity = $2
    quantity_unit = $3
WHERE id = $4
RETURNING id, product_id, quantity, quantity_unit
    "#,
    )
    .bind(msg.product_id)
    .bind(msg.quantity)
    .bind(msg.quantity_unit)
    .bind(msg.id)
    .fetch_one(&pool)
    .await
    .map_err(|e| {
        log::error!("{e:?}");
        crate::Error::Stock(Error::Update)
    })
}

#[derive(Message)]
#[rtype(result = "Result<Option<model::Stock>>")]
pub struct DeleteStock {
    pub stock_id: StockId,
}

crate::db_async_handler!(DeleteStock, delete_stock, Option<model::Stock>);

async fn delete_stock(msg: DeleteStock, pool: PgPool) -> Result<Option<Stock>> {
    sqlx::query_as(
        r#"
DELETE FROM stocks
WHERE id = $1
RETURNING id, product_id, quantity, quantity_unit
    "#,
    )
    .bind(msg.stock_id)
    .fetch_optional(&pool)
    .await
    .map_err(|e| {
        log::error!("{e:?}");
        crate::Error::Stock(Error::Delete)
    })
}

#[derive(Message)]
#[rtype(result = "Result<Vec<model::Stock>>")]
pub struct ProductsStock {
    pub product_ids: Vec<ProductId>,
}

crate::db_async_handler!(
    ProductsStock,
    product_stock,
    Vec<model::Stock>,
    inner_product_stock
);

async fn product_stock(
    msg: ProductsStock,
    pool: &mut sqlx::Transaction<'_, sqlx::Postgres>,
) -> Result<Vec<model::Stock>> {
    Ok(MultiLoad::new(
        pool,
        r#"
    SELECT id, product_id, quantity, quantity_unit
    FROM stocks
    WHERE 
    "#,
        " product_id =",
    )
    .load(
        msg.product_ids.len(),
        msg.product_ids.into_iter().map(|id| *id),
        |_e| crate::Error::Stock(Error::ProductStock),
    )
    .await?)
}