From e36b3a20121ad237d4405a57e0499be5967f8768 Mon Sep 17 00:00:00 2001
From: Ian Roddis <gitlab@ie2r.com>
Date: Sat, 5 Jun 2021 19:56:40 -0300
Subject: [PATCH] checkpoint

---
 README.md                   | 10 ++---
 daggy/include/daggy/DAG.hpp | 88 +++++++++++++++----------------------
 2 files changed, 39 insertions(+), 59 deletions(-)

diff --git a/README.md b/README.md
index 17fc663..23fac46 100644
--- a/README.md
+++ b/README.md
@@ -7,12 +7,6 @@ Daggy is a work orchestration framework for running workflows modeled as
 directed, acyclic graphs (DAGs). These are quite useful when modeling
 data ingestion / processing pipelines.
 
-
-Requirements
-==
-
-- rapidjson
-
 Building
 ==
 
@@ -24,3 +18,7 @@ cd build
 cmake ..
 make
 ```
+
+Architecture
+==
+
diff --git a/daggy/include/daggy/DAG.hpp b/daggy/include/daggy/DAG.hpp
index b78cada..b46baf6 100644
--- a/daggy/include/daggy/DAG.hpp
+++ b/daggy/include/daggy/DAG.hpp
@@ -8,67 +8,49 @@
 #include <iterator>
 #include <functional>
 
+/*
+   The DAG structure in daggy is just to ensure that tasks are run
+   in the correct dependent order.
+*/
+
 namespace daggy {
-    template<typename T>
-    class DAG {
-        public:
-            DAG() {}
 
-            void addVertex(T id);
-            void dropVertex(const T & id);
+  template<typename T>
+  class DAG {
+    public:
+      DAG() {}
 
-            void addEdge(const T & src, const T & dst);
-            void dropEdge(const T & src, const T & dst);
+      // Vertices
+      void addVertex(T id);
+      void dropVertex(const T & id);
+      void setVertexVisited(const T & id, bool visited);
+      void setDAGVisited(bool visited);
 
-            // Returns the path from {from} to {to}
-            std::deque<T> shortestPath(const T & from, const T & to);
+      // Edges
+      void addEdge(const T & src, const T & dst);
+      void dropEdge(const T & src, const T & dst);
 
-            // Traversal
+      // Returns the path from {from} to {to}
+      std::deque<T> shortestPath(const T & from, const T & to);
 
-            // Traverse all nodes, calling f(id). If f() returns
-            // false, stop traversing this branch.
-            // Guarantees to only visit each vertex once.
-            void traverse(std::function<bool> f);
+      // Traversal
+      void initTraversal(std::vector<const T&> ids = {});
+      const T & visitNextVertex();
 
-            // Same as traverse, but starts the traversal at
-            // the given id.
-            void traverseFrom(T& id, std::function<bool> f);
+    private:
+      struct Vertex {
+        // It's a bit redundant to preserve both, but
+        // it makes it possible with and against the
+        // directions possible
+        std::unordered_set<T> parents;
+        std::unordered_set<T> children;
+        bool visited;
+      };
 
-
-            // Peek at the next node
-            T & next() const;
-
-            // Get the next node and mark it visited
-            T & visit_next();
-
-            // Clear the visited flag, optionally for downstream
-            // vertices
-            void unvisit(T &id, bool cascade = true);
-
-            // Breadth First Iterator
-            struct Iterator {
-              using iterator_category = std::random_access_iterator_tag;
-              using difference_type   = int;
-              using value_type        = T;
-              using point             = T*;
-              using reference         = T&;
-            };
-
-        private:
-
-
-            struct Vertex {
-                // It's a bit redundant to preserve both, but
-                // it makes it possible with and against the
-                // directions possible
-                std::unordered_set<T> parents;
-                std::unordered_set<T> children;
-                bool visited;
-            };
-
-            std::unordered_map<T, Vertex> vertices;
-            std::unordered_set<T> roots;
-    };
+      std::unordered_map<T, Vertex> vertices;
+      std::unordered_set<T> roots;
+      std::unordered_set<T> active_nodes;
+  };
 
 #include "DAG.impl"
 }