From 370276fb56fe2a03f1b863eca8e73a2b19d277fb Mon Sep 17 00:00:00 2001
From: Avril <flanchan@cumallover.me>
Date: Wed, 18 Nov 2020 23:47:18 +0000
Subject: [PATCH] hook events

---
 src/ext.rs          | 51 +++++++++++++++++++++++++++++++++++++++++++++
 src/server/data.rs  |  3 +++
 src/server/event.rs | 33 +++++++++++++++++++++++++----
 src/server/user.rs  | 11 ++--------
 4 files changed, 85 insertions(+), 13 deletions(-)

diff --git a/src/ext.rs b/src/ext.rs
index 08ceb0a..1e23ae0 100644
--- a/src/ext.rs
+++ b/src/ext.rs
@@ -126,3 +126,54 @@ where S: IntoIterator<Item=T>,
     }
 }
 
+/// The ID type used for backing ID types;
+pub type GenericID = uuid::Uuid;
+
+
+/// Create a type that contains a (globally) unique ID.
+#[macro_export] macro_rules! id_type {
+    ($name:ident $(: $doc:literal)?) => ($crate::id_type!{pub(self) $name $(: $doc)?});
+    ($vis:vis $name:ident $(: $doc:literal)?) => {
+	$(#[doc=$doc])?
+	#[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]	
+	$vis struct $name($crate::ext::GenericID);
+
+	impl $name
+	{
+	    /// Create a new unique ID.
+	    #[inline(always)] fn id_new() -> Self
+	    {
+		Self($crate::ext::GenericID::new_v4())
+	    }
+
+	    /// The generic ID type backing this one
+	    #[inline(always)] fn id_generic(&self) -> &$crate::ext::GenericID
+	    {
+		&self.0
+	    }
+
+	    /// Consume into the generic ID
+	    #[inline(always)] fn id_into_generic(self) -> $crate::ext::GenericID
+	    {
+		self.0
+	    }
+
+	    /// Create from a generic ID
+	    #[inline(always)] fn id_from_generic(gen: $crate::ext::GenericID) -> Self
+	    {
+		Self(gen)
+	    }
+	}
+
+	impl ::std::fmt::Display for $name
+	{
+	    fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result
+	    {
+		use ::std::fmt::Write;
+		f.write_str(concat!(stringify!($name),"<"))?;
+		self.0.fmt(f)?;
+		f.write_str(">")
+	    }
+	}
+    }
+}
diff --git a/src/server/data.rs b/src/server/data.rs
index 378af17..a37caaf 100644
--- a/src/server/data.rs
+++ b/src/server/data.rs
@@ -112,6 +112,9 @@ pub struct Info
 
     tags: Tags,
 
+    /// Events to be emitted to `State` when this element does something.
+    ///
+    /// Can be used for monitoring or logging and such.
     hooks: event::Hooks,
 
     owner: Option<Vec<user::EntityID>>, //starts as the user that created (i.e. same as `created_by`), or `None` if ownership is disabled
diff --git a/src/server/event.rs b/src/server/event.rs
index b8cfec0..13b8fbe 100644
--- a/src/server/event.rs
+++ b/src/server/event.rs
@@ -50,7 +50,7 @@ bitflags! {
 	/// Emmit delete events.
 	const DELETE = 1<<2;
 	
-	/// Propagate events from children of `Map` datas
+	/// Propagate events from children of `Map` or `List` datas
 	const CHILD  = 1<<3;
 
 	/// Poke events are opaque events that are fired manually.
@@ -68,28 +68,45 @@ impl Default for HookMask
     }
 }
 
+id_type!(pub HookID: "The ID of a hook, passed with the event when the hook is fired");
 
 /// Fire events when something happens to this value.
 #[derive(Debug, Serialize, Deserialize)]
 pub struct Hooks
 {
     filter: HookMask,
+    id: HookID,
+}
+
+impl Default for Hooks
+{
+    #[inline]
+    fn default() -> Self
+    {
+	Self {
+	    id: HookID::id_new(), // generate an id now, in case hooks are added later
+	    filter: Default::default(), //default is to emit nothing ever
+	}
+    }
 }
 
 /// An event emitted from a matched `Hook`.
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Ord, PartialOrd)]
-pub enum HookEvent
+pub enum HookEventKind
 {
-    /// An opaque event type
+    /// An opaque event type that can only be fired manually.
     Poke,
     
     Read,
     Write,
     Delete,
+    /// An event propagated from a child of this element.
+    ///
+    /// This only can happen with `Map` or `List` data kinds.
     Child(Box<HookEvent>),
 }
 
-impl Default for HookEvent
+impl Default for HookEventKind
 {
     #[inline]
     fn default() -> Self
@@ -98,3 +115,11 @@ impl Default for HookEvent
     }
 }
 
+/// An event emitted from a element value's `Hooks` object.
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Ord, PartialOrd)]
+pub struct HookEvent
+{
+    kind: HookEventKind,
+    /// Corresponds to the `id` field of the `Hooks` object this event was emitted from.
+    id: HookID,
+}
diff --git a/src/server/user.rs b/src/server/user.rs
index 09d8956..58ea4e6 100644
--- a/src/server/user.rs
+++ b/src/server/user.rs
@@ -4,16 +4,9 @@ use std::collections::HashMap;
 use std::borrow::Cow;
 use bitflags::bitflags;
 
-/// The ID type used for backing user/group IDs
-type GenericID = uuid::Uuid;
 
-/// A user group ID
-#[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
-pub struct GroupID(GenericID);
-
-/// A unique user ID
-#[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
-pub struct UserID(GenericID);
+id_type!(pub UserID: "A unique user ID");
+id_type!(pub GroupID: "A user group ID");
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct User