feat(api): build bingo card generation

src/api/bingo_card.rs

@@ -0,0 +1,94 @@
+use std::sync::Arc;
+use rand::seq::SliceRandom;
+use rand::rng;
+use sqlx::PgPool;
+use sqlx::postgres::PgQueryResult;
+use uuid::Uuid;
+use crate::model;
+use crate::model::bingo_card::BingoCard;
+use crate::model::database::BingoCardField;
+use crate::model::database::Train;
+
+pub(crate) async fn get(id: Uuid, db: Arc<PgPool>) -> sqlx::Result<BingoCard> {
+    let card = sqlx::query_as!(
+        crate::model::database::BingoCard,
+        "SELECT uuid as id FROM bingo_cards WHERE uuid = $1",
+        id,
+    ).fetch_one(db.as_ref()).await?;
+    let mut raw_fields = get_fields_with_train(card.id, db.clone())
+        .await?;
+    raw_fields.sort_by(|a, b| (a.y * 5 + a.x).partial_cmp(&(b.y * 5 + b.x)).unwrap());
+    raw_fields.truncate(24);
+    raw_fields.shrink_to_fit();
+    let fields: [Train; 24] = raw_fields
+        .into_iter()
+        .map(|field| field.train)
+        .collect::<Vec<Train>>()
+        .try_into()
+        .unwrap_or_else(|v: Vec<Train>| panic!("Expected a Vec of length 24 but it was {}", v.len()));
+    Ok(BingoCard {
+        id: card.id,
+        fields
+    })
+}
+
+async fn get_fields_with_train(id: Uuid, db: Arc<PgPool>) -> sqlx::Result<Vec<BingoCardField>> {
+    sqlx::query_as(
+        "SELECT c.uuid, c.x_pos, c.y_pos, c.card_uuid, t.uuid, t.tz_id, t.name FROM bingo_card c LEFT JOIN triebzug t ON t.uuid = c.triebzug WHERE card_uuid = $1"
+    )
+        .bind(id)
+        .fetch_all(db.as_ref())
+        .await
+}
+
+pub(crate) async fn generate(db: Arc<PgPool>) -> sqlx::Result<BingoCard> {
+    let card_id = Uuid::new_v4();
+    let mut all_trains = fetch_all(db.clone()).await?;
+    all_trains.shuffle(&mut rng());
+    all_trains.truncate(24);
+    all_trains.shrink_to_fit();
+    let trains = all_trains.to_owned();
+    let fields = trains
+        .into_iter()
+        .enumerate()
+        .map(|(idx, train)| BingoCardField {
+            uuid: Uuid::new_v4(),
+            x: (idx as i32).rem_euclid(5),
+            y: (idx as i32).div_euclid(5),
+            train,
+            card_id
+        })
+        .collect::<Vec<BingoCardField>>();
+    let card = model::database::BingoCard {
+        id: card_id,
+    };
+    save_card(card, db.clone()).await?;
+    for field in fields {
+        save_card_field(field, db.clone()).await?;
+    }
+    get(card_id, db.clone()).await
+}
+
+async fn save_card(card: model::database::BingoCard, db: Arc<PgPool>) -> sqlx::Result<PgQueryResult> {
+    sqlx::query!(
+        "INSERT INTO bingo_cards VALUES ($1, NOW(), NOW() + interval '7 day')",
+        card.id
+    ).execute(db.as_ref()).await
+}
+
+async fn save_card_field(field: BingoCardField, db: Arc<PgPool>) -> sqlx::Result<PgQueryResult> {
+    sqlx::query!(
+        "INSERT INTO bingo_card VALUES ($1, $2, $3, $4, $5)",
+        field.uuid,
+        field.x,
+        field.y,
+        field.train.uuid,
+        field.card_id
+    ).execute(db.as_ref()).await
+}
+
+async fn fetch_all(db: Arc<PgPool>) -> sqlx::Result<Vec<Train>> {
+    sqlx::query_as("SELECT * FROM triebzug")
+        .fetch_all(db.as_ref())
+        .await
+}

src/api/mod.rs

@@ -1,2 +1,3 @@
 pub(crate) mod handlers;
-mod db_vendo_navigator;
+pub(crate) mod bingo_card;
+mod db_vendo_navigator;