add: postgres support

chore: restructure

crates/tetratto_core/src/model/mod.rs

@@ -0,0 +1,56 @@
+pub mod auth;
+use serde::{Deserialize, Serialize};
+
+#[derive(Serialize, Deserialize)]
+pub struct ApiReturn<T>
+where
+    T: Serialize,
+{
+    pub ok: bool,
+    pub message: String,
+    pub payload: T,
+}
+
+#[derive(Debug)]
+pub enum Error {
+    DatabaseConnection(String),
+    UserNotFound,
+    RegistrationDisabled,
+    DatabaseError(String),
+    IncorrectPassword,
+    AlreadyAuthenticated,
+    DataTooLong(String),
+    DataTooShort(String),
+    Unknown,
+}
+
+impl ToString for Error {
+    fn to_string(&self) -> String {
+        match self {
+            Error::DatabaseConnection(msg) => msg.to_owned(),
+            Error::DatabaseError(msg) => format!("Database error: {msg}"),
+            Error::UserNotFound => "Unable to find user with given parameters".to_string(),
+            Error::RegistrationDisabled => "Registration is disabled".to_string(),
+            Error::IncorrectPassword => "The given password is invalid".to_string(),
+            Error::AlreadyAuthenticated => "Already authenticated".to_string(),
+            Error::DataTooLong(name) => format!("Given {name} is too long!"),
+            Error::DataTooShort(name) => format!("Given {name} is too short!"),
+            _ => format!("An unknown error as occurred: ({:?})", self),
+        }
+    }
+}
+
+impl<T> Into<ApiReturn<T>> for Error
+where
+    T: Default + Serialize,
+{
+    fn into(self) -> ApiReturn<T> {
+        ApiReturn {
+            ok: false,
+            message: self.to_string(),
+            payload: T::default(),
+        }
+    }
+}
+
+pub type Result<T> = std::result::Result<T, Error>;