refactor: combine models and db crate together

crates/core/database/src/drivers/dummy.rs

@@ -1,4 +0,0 @@
-database_derived!(
-    /// Dummy implementation
-    pub struct DummyDb {}
-);

crates/core/database/src/drivers/mod.rs

@@ -1,5 +1,51 @@
-mod dummy;
 mod mongodb;
+mod reference;
 
-pub use self::dummy::*;
 pub use self::mongodb::*;
+pub use self::reference::*;
+
+/// Database information to use to create a client
+pub enum DatabaseInfo {
+    /// Auto-detect the database in use
+    Auto,
+    /// Use the mock database
+    Reference,
+    /// Connect to MongoDB
+    MongoDb(String),
+    /// Use existing MongoDB connection
+    MongoDbFromClient(::mongodb::Client),
+}
+
+/// Database
+#[derive(Clone)]
+pub enum Database {
+    /// Mock database
+    Reference(ReferenceDb),
+    /// MongoDB database
+    MongoDb(MongoDb),
+}
+
+impl DatabaseInfo {
+    /// Create a database client from the given database information
+    #[async_recursion]
+    pub async fn connect(self) -> Result<Database, String> {
+        Ok(match self {
+            DatabaseInfo::Auto => {
+                if let Ok(uri) = std::env::var("MONGODB") {
+                    return DatabaseInfo::MongoDb(uri).connect().await;
+                }
+
+                DatabaseInfo::Reference.connect().await?
+            }
+            DatabaseInfo::Reference => Database::Reference(Default::default()),
+            DatabaseInfo::MongoDb(uri) => {
+                let client = ::mongodb::Client::with_uri_str(uri)
+                    .await
+                    .map_err(|_| "Failed to init db connection.".to_string())?;
+
+                Database::MongoDb(MongoDb(client))
+            }
+            DatabaseInfo::MongoDbFromClient(client) => Database::MongoDb(MongoDb(client)),
+        })
+    }
+}

crates/core/database/src/drivers/reference.rs

@@ -0,0 +1,13 @@
+use std::{collections::HashMap, sync::Arc};
+
+use futures::lock::Mutex;
+
+use crate::Bot;
+
+database_derived!(
+    /// Reference implementation
+    #[derive(Default)]
+    pub struct ReferenceDb {
+        pub bots: Arc<Mutex<HashMap<String, Bot>>>,
+    }
+);