From 9c42ab2552422db665ea3548c0867cb3e2d0deb0 Mon Sep 17 00:00:00 2001
From: Chris Tsang <tyt2y7@gmail.com>
Date: Tue, 25 May 2021 00:38:21 +0800
Subject: [PATCH] ActiveModel

---
 src/entity/active_model.rs | 34 ++++++++++++++++++++++++++
 src/entity/mod.rs          |  2 ++
 src/entity/prelude.rs      |  2 +-
 src/tests_cfg/cake.rs      | 50 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 87 insertions(+), 1 deletion(-)
 create mode 100644 src/entity/active_model.rs

diff --git a/src/entity/active_model.rs b/src/entity/active_model.rs
new file mode 100644
index 00000000..5f436568
--- /dev/null
+++ b/src/entity/active_model.rs
@@ -0,0 +1,34 @@
+use std::fmt::Debug;
+use crate::{ColumnTrait, ModelTrait, Value};
+
+#[derive(Clone, Debug)]
+pub enum Action<V> {
+    Set(V),
+    Unset,
+}
+
+impl<V> Action<V> where V: Into<Value> {
+    pub fn into_action_value(self) -> Action<Value> {
+        match self {
+            Self::Set(v) => Action::Set(v.into()),
+            Self::Unset => Action::Unset,
+        }
+    }
+}
+
+pub trait ActiveModelOf<M>
+where
+    M: ModelTrait,
+{
+    fn from_model(m: M) -> Self;
+}
+
+pub trait ActiveModelTrait: Clone + Debug {
+    type Column: ColumnTrait;
+
+    fn get(&self, c: Self::Column) -> Action<Value>;
+
+    fn set(&mut self, c: Self::Column, v: Value);
+
+    fn unset(&mut self, c: Self::Column);
+}
\ No newline at end of file
diff --git a/src/entity/mod.rs b/src/entity/mod.rs
index 06b63301..0fa11b87 100644
--- a/src/entity/mod.rs
+++ b/src/entity/mod.rs
@@ -1,3 +1,4 @@
+mod active_model;
 mod base;
 mod column;
 mod identity;
@@ -6,6 +7,7 @@ pub mod prelude;
 mod primary_key;
 mod relation;
 
+pub use active_model::*;
 pub use base::*;
 pub use column::*;
 pub use identity::*;
diff --git a/src/entity/prelude.rs b/src/entity/prelude.rs
index d9521003..01e11c68 100644
--- a/src/entity/prelude.rs
+++ b/src/entity/prelude.rs
@@ -1,5 +1,5 @@
 pub use crate::{
-    ColumnTrait, ColumnType, DeriveColumn, DeriveEntity, DeriveModel, DerivePrimaryKey, EntityName,
+    Action, ActiveModelOf, ActiveModelTrait, ColumnTrait, ColumnType, DeriveColumn, DeriveEntity, DeriveModel, DerivePrimaryKey, EntityName,
     EntityTrait, EnumIter, Iden, IdenStatic, ModelTrait, PrimaryKeyOfModel, PrimaryKeyTrait,
     QueryResult, Related, RelationDef, RelationTrait, Select, TypeErr, Value,
 };
diff --git a/src/tests_cfg/cake.rs b/src/tests_cfg/cake.rs
index d61c13ee..46a14765 100644
--- a/src/tests_cfg/cake.rs
+++ b/src/tests_cfg/cake.rs
@@ -11,6 +11,13 @@ pub struct Model {
     pub name: String,
 }
 
+// can we generate this?
+#[derive(Clone, Debug)]
+pub struct ActiveModel {
+    pub id: Action<i32>,
+    pub name: Action<String>,
+}
+
 #[derive(Copy, Clone, Debug, EnumIter, DeriveColumn)]
 pub enum Column {
     Id,
@@ -74,3 +81,46 @@ impl Model {
         Entity::find_related().belongs_to::<Entity>(self)
     }
 }
+
+// can we generate this?
+impl ActiveModelOf<Model> for ActiveModel {
+    fn from_model(m: Model) -> Self {
+        Self::from(m)
+    }
+}
+
+// can we generate this?
+impl From<Model> for ActiveModel {
+    fn from(m: Model) -> Self {
+        Self {
+            id: Action::Set(m.id),
+            name: Action::Set(m.name),
+        }
+    }
+}
+
+// can we generate this?
+impl ActiveModelTrait for ActiveModel {
+    type Column = Column;
+
+    fn get(&self, c: Self::Column) -> Action<Value> {
+        match c {
+            Column::Id => self.id.clone().into_action_value(),
+            Column::Name => self.name.clone().into_action_value(),
+        }
+    }
+
+    fn set(&mut self, c: Self::Column, v: Value) {
+        match c {
+            Column::Id => self.id = Action::Set(v.unwrap()),
+            Column::Name => self.name = Action::Set(v.unwrap()),
+        }
+    }
+
+    fn unset(&mut self, c: Self::Column) {
+        match c {
+            Column::Id => self.id = Action::Unset,
+            Column::Name => self.name = Action::Unset,
+        }
+    }
+}
\ No newline at end of file