From 503aff9997e068f07ab6973f56e57282a5ba27a0 Mon Sep 17 00:00:00 2001
From: Avril <flanchan@cumallover.me>
Date: Wed, 23 Dec 2020 17:35:03 +0000
Subject: [PATCH] clean template

---
 Cargo.lock        |  1 +
 Cargo.toml        |  1 +
 src/data/clean.rs | 50 +++++++++++++++++++++++++++++++++++++++++++++++
 src/data/mod.rs   |  3 +++
 src/ext/mod.rs    | 33 +++++++++++++++++++++++++++++++
 src/main.rs       |  3 ++-
 6 files changed, 90 insertions(+), 1 deletion(-)
 create mode 100644 src/data/clean.rs

diff --git a/Cargo.lock b/Cargo.lock
index 33897df..b7457b8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -468,6 +468,7 @@ name = "mtfse"
 version = "0.1.0"
 dependencies = [
  "ad-hoc-iter",
+ "bitflags",
  "bytes 0.6.0",
  "cryptohelpers",
  "futures",
diff --git a/Cargo.toml b/Cargo.toml
index 32b639f..c1cb35c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,7 @@ edition = "2018"
 
 [dependencies]
 ad-hoc-iter = "0.2.2"
+bitflags = "1.2.1"
 bytes = "0.6.0"
 cryptohelpers = {version = "1.7", features = ["full", "async", "serde"]}
 futures = "0.3.8"
diff --git a/src/data/clean.rs b/src/data/clean.rs
new file mode 100644
index 0000000..4f2f576
--- /dev/null
+++ b/src/data/clean.rs
@@ -0,0 +1,50 @@
+use super::*;
+
+bitflags!{
+    /// What to remove when using `Store::clean()`.
+    pub struct StoreCleanFlags: u32
+    {
+	/// Dead entry hash (key) mappings.
+	const MAP     = 1 << 0;
+	/// Dead `tag -> entry hash` mappings.
+	const TAG_MAP = 1 << 1;
+	/// Dead tags (i.e. tags with no entries).
+	const TAGS    = 1 << 2;
+	/// Dead entries (i.e. Inaccessable, corrupt, or missing file entries).
+	const ENTRY   = 1 << 3;
+
+	/// Clean all
+	const ALL     = (1 << 4)-1;
+	
+    }
+}
+impl Default for StoreCleanFlags
+{
+    #[inline]
+    fn default() -> Self
+    {
+	Self::MAP | Self::TAG_MAP | Self::TAGS
+    }
+}
+
+
+// Refresh and cleaning
+impl Store
+{
+    /// Remove any and all dead mappings / entries specified by the flags here.
+    ///
+    /// Pass `Default::default()` to only clean *mappings*, and not dead entries. Otherwise, `StoreCleanFlags::ALL` will perform a full audit.
+    /// See [`StoreCleanFlags`] for other options.
+    pub fn clean(&mut self, what: StoreCleanFlags)
+    {
+	todo!("What order do we do `what`'s things in?")
+    }
+    /// Force a full rebuild of all mappings.
+    ///
+    /// The clears the entire store except entries (and entry specific caches), and then rebuilds all the internal mappings from scratch. Any cached mappings (e.g empty tag reserves) are removed.
+    /// This does not remove invalid entries themselves, for that use `clean(StoreCleanFlags::ENTRY)`.
+    pub fn rebuild(&mut self)
+    {
+	todo!()
+    }
+}
diff --git a/src/data/mod.rs b/src/data/mod.rs
index 499ff7a..792034c 100644
--- a/src/data/mod.rs
+++ b/src/data/mod.rs
@@ -35,6 +35,9 @@ pub use search::*;
 mod mutation;
 pub use mutation::*;
 
+mod clean;
+pub use clean::*;
+
 #[cfg(test)] mod test;
 
 /// The key used to look up a single entry in `O(1)` time.
diff --git a/src/ext/mod.rs b/src/ext/mod.rs
index 2e6f000..c64fc33 100644
--- a/src/ext/mod.rs
+++ b/src/ext/mod.rs
@@ -41,3 +41,36 @@ pub const PRECOLLECT_STACK_SIZE: usize = 64;
 	}
     };
 }
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Copy)]
+pub enum Either<T,U>
+{
+    T(T),
+    U(U),
+}
+
+impl<T,U> Either<T,U>
+{
+    /// Convert this sum type into 
+    pub fn cast<V>(self) -> V
+    where V: From<T> + From<U>// eh, this doesn't work. forget about it.
+    {
+	match self {
+	    Self::T(t) => t.into(),
+	    Self::U(u) => u.into(),
+	}
+    }
+}
+
+/// Create an ad-hoc sum type.
+macro_rules! either {
+    (@ type $first:ty) => {
+	$first
+    };
+    (@ type $first:ty, $($rest:ty),*) => {
+	Either<$first, either!(@ type $($rest),*)>
+    };
+    (type $($type:ty)|*) => {
+	either!(@ type $($type),*)
+    };
+}
diff --git a/src/main.rs b/src/main.rs
index 66300b8..aeeb9aa 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,6 +3,7 @@
 #![allow(dead_code)]
 
 #[macro_use] extern crate ad_hoc_iter;
+#[macro_use] extern crate bitflags;
 
 use serde::{Serialize, Deserialize};
 
@@ -22,7 +23,7 @@ mod ext;
 use ext::*;
 
 mod slice;
-mod data;
+pub mod data;
 
 fn main() {
     println!("Hello, world!");