From 4139c98917164d2c52e3a89f35ec980da64daa95 Mon Sep 17 00:00:00 2001
From: trivernis <trivernis@protonmail.com>
Date: Sun, 30 Aug 2020 18:43:15 +0200
Subject: [PATCH] Add BibRef manager, entries and anchors

---
 .idea/discord.xml                   |  6 +++
 src/lib.rs                          | 18 +++++++-
 src/references/anchor.rs            | 64 +++++++++++++++++++++++++++++
 src/references/bib_reference.rs     | 13 ++++++
 src/references/mod.rs               |  3 ++
 src/references/reference_manager.rs | 23 +++++++++++
 6 files changed, 125 insertions(+), 2 deletions(-)
 create mode 100644 .idea/discord.xml
 create mode 100644 src/references/anchor.rs
 create mode 100644 src/references/bib_reference.rs
 create mode 100644 src/references/mod.rs
 create mode 100644 src/references/reference_manager.rs

diff --git a/.idea/discord.xml b/.idea/discord.xml
new file mode 100644
index 0000000..cd711a0
--- /dev/null
+++ b/.idea/discord.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="DiscordProjectSettings">
+    <option name="show" value="PROJECT_FILES" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index 31e1bb2..f03d154 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,7 +1,21 @@
+pub mod references;
+
 #[cfg(test)]
 mod tests {
+    use crate::references::reference_manager::BibRefManager;
+    use crate::references::bib_reference::BibRef;
+
     #[test]
-    fn it_works() {
-        assert_eq!(2 + 2, 4);
+    fn it_inserts_and_flattens() {
+        let manager = BibRefManager::new();
+        let root_anchor = manager.root_anchor();
+        let mut root_anchor = root_anchor.lock().unwrap();
+        root_anchor.insert(BibRef::new("test".to_string()));
+        let child_anchor = root_anchor.create_anchor();
+        child_anchor.lock().unwrap().insert(BibRef::new("test2".to_string()));
+        child_anchor.lock().unwrap().insert(BibRef::new("test3".to_string()));
+        root_anchor.flatten();
+
+        assert_eq!(root_anchor.references().len(), 3)
     }
 }
diff --git a/src/references/anchor.rs b/src/references/anchor.rs
new file mode 100644
index 0000000..adca40b
--- /dev/null
+++ b/src/references/anchor.rs
@@ -0,0 +1,64 @@
+use crate::references::bib_reference::BibRef;
+use std::sync::{Arc, Mutex};
+
+/// A bib list anchor that can be used to concurrently insert entries into a list
+#[derive(Clone, Debug)]
+pub struct BibListAnchor {
+    entries: Vec<BibListEntry>,
+}
+
+/// Enum that represents a single entry of a bib list
+#[derive(Clone, Debug)]
+enum BibListEntry {
+    Ref(BibRef),
+    Anchor(Arc<Mutex<BibListAnchor>>),
+}
+
+impl BibListAnchor {
+    /// Creates a new empty BibListAnchor.
+    pub fn new() -> Self {
+        Self {
+            entries: Vec::new(),
+        }
+    }
+
+    /// Inserts a reference at the current position
+    pub fn insert(&mut self, bib_ref: BibRef) {
+        self.entries.push(BibListEntry::Ref(bib_ref))
+    }
+
+    /// Creates a new anchor at the current position and inserts it into the entry vec.
+    pub fn create_anchor(&mut self) -> Arc<Mutex<BibListAnchor>> {
+        let anchor = Arc::new(Mutex::new(BibListAnchor::new()));
+        self.entries.push(BibListEntry::Anchor(Arc::clone(&anchor)));
+
+        anchor
+    }
+
+    /// Flattens the inner entry structure by inserting the elements of child anchors for every
+    /// anchor in the vector
+    pub fn flatten(&mut self) {
+        let mut new_entries = Vec::with_capacity(self.entries.len());
+        self.entries.iter_mut().for_each(|e| {
+            match e {
+                BibListEntry::Anchor(a) => {
+                    let mut anchor = a.lock().unwrap();
+                    anchor.flatten();
+                    new_entries.append(&mut anchor.entries);
+                }
+                BibListEntry::Ref(bib_ref) => new_entries.push(BibListEntry::Ref(bib_ref.clone()))
+            }
+        });
+
+        self.entries = new_entries;
+    }
+
+    /// Returns all references that are contained in the entry list
+    pub fn references(&self) -> Vec<BibRef> {
+        self.entries.iter().filter_map(|e| if let BibListEntry::Ref(r) = e {
+            Some(r.clone())
+        } else {
+            None
+        }).collect()
+    }
+}
\ No newline at end of file
diff --git a/src/references/bib_reference.rs b/src/references/bib_reference.rs
new file mode 100644
index 0000000..854139e
--- /dev/null
+++ b/src/references/bib_reference.rs
@@ -0,0 +1,13 @@
+#[derive(Clone, Debug)]
+pub struct BibRef {
+    key: String,
+}
+
+impl BibRef {
+    /// Creates a new BibRef with a given key
+    pub fn new(key: String) -> Self {
+        Self {
+            key
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/references/mod.rs b/src/references/mod.rs
new file mode 100644
index 0000000..653240e
--- /dev/null
+++ b/src/references/mod.rs
@@ -0,0 +1,3 @@
+pub mod reference_manager;
+pub mod bib_reference;
+pub mod anchor;
\ No newline at end of file
diff --git a/src/references/reference_manager.rs b/src/references/reference_manager.rs
new file mode 100644
index 0000000..3b8b133
--- /dev/null
+++ b/src/references/reference_manager.rs
@@ -0,0 +1,23 @@
+use std::sync::{Arc, Mutex};
+use crate::references::anchor::BibListAnchor;
+
+/// The root manager for references that should be used for further reference operations that
+/// go beyond insertion.
+#[derive(Clone, Debug)]
+pub struct BibRefManager {
+    root_anchor: Arc<Mutex<BibListAnchor>>,
+}
+
+impl BibRefManager {
+    /// Creates a new BibRefManager with an empty root anchor
+    pub fn new() -> Self {
+        Self {
+            root_anchor: Arc::new(Mutex::new(BibListAnchor::new()))
+        }
+    }
+
+    /// Returns the BibRefManagers root anchor that.
+    pub fn root_anchor(&self) -> Arc<Mutex<BibListAnchor>> {
+        Arc::clone(&self.root_anchor)
+    }
+}
\ No newline at end of file