Calendar is now displayed on home page and recipes can be scheduled without being logged

backend/src/data/db/recipe.rs

@@ -1,7 +1,7 @@
 use chrono::prelude::*;
 use common::ron_api::Difficulty;
 use itertools::Itertools;
-use sqlx::Error;
+use sqlx::{Error, Sqlite};
 
 use super::{Connection, DBError, Result};
 use crate::data::model;
@@ -64,6 +64,37 @@ ORDER BY [title]
         .map_err(DBError::from)
     }
 
+    /// Returns titles associated to given ids in the same order.
+    /// Empty string for unknown id.
+    pub async fn get_recipe_titles(&self, ids: &[i64]) -> Result<Vec<String>> {
+        let mut query_builder: sqlx::QueryBuilder<Sqlite> =
+            sqlx::QueryBuilder::new("SELECT [id], [title] FROM [Recipe] WHERE [id] IN(");
+        let mut separated = query_builder.separated(", ");
+        for id in ids {
+            separated.push_bind(id);
+        }
+        separated.push_unseparated(")");
+        let query = query_builder.build_query_as::<(i64, String)>();
+        let titles = query.fetch_all(&self.pool).await?;
+        let mut result = vec![];
+        // Warning: O(n^2), OK for small number of ids.
+        for id in ids {
+            result.push(
+                titles
+                    .iter()
+                    .find_map(|(fetched_id, title)| {
+                        if fetched_id == id {
+                            Some(title.clone())
+                        } else {
+                            None
+                        }
+                    })
+                    .unwrap_or_default(),
+            );
+        }
+        Ok(result)
+    }
+
     pub async fn can_edit_recipe(&self, user_id: i64, recipe_id: i64) -> Result<bool> {
         sqlx::query_scalar(
             r#"