From 9c03fcdb959de10a91d043dc2cf877d226138d1f Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Mon, 5 Feb 2018 11:49:40 -0800
Subject: [PATCH] ircd::m::state: Basic util suite.

---
 include/ircd/m/state.h | 19 +++++++-----
 ircd/m/state.cc        | 70 ++++++++++++++++++++++++++++++++++++------
 2 files changed, 73 insertions(+), 16 deletions(-)

diff --git a/include/ircd/m/state.h b/include/ircd/m/state.h
index 8e11ce2b9..dccf3f213 100644
--- a/include/ircd/m/state.h
+++ b/include/ircd/m/state.h
@@ -28,9 +28,6 @@ namespace ircd::m::state
 	struct init;
 	struct node;
 
-	using id_closure = std::function<void (const string_view &)>;
-	using node_closure = std::function<void (const json::object &)>;
-
 	constexpr size_t ID_MAX_SZ { 64 };
 	constexpr size_t KEY_MAX_SZ { 256 + 256 + 16 };
 	constexpr size_t VAL_MAX_SZ { 256 + 16 };
@@ -40,11 +37,16 @@ namespace ircd::m::state
 	constexpr size_t NODE_MAX_DEG { NODE_MAX_KEY + 1 }; // tmp for now
 	constexpr int8_t MAX_HEIGHT { 16 }; // good for few mil at any degree :)
 
+	using id_closure = std::function<void (const string_view &)>;
+	using node_closure = std::function<void (const json::object &)>;
+	using search_closure = std::function<bool (const json::array &, const string_view &, const uint &, const uint &)>;
+	using iter_closure = std::function<void (const json::array &, const string_view &)>;
+	using iter_bool_closure = std::function<bool (const json::array &, const string_view &)>;
+
 	int keycmp(const json::array &a, const json::array &b);
-
 	json::array make_key(const mutable_buffer &out, const string_view &type, const string_view &state_key);
-	string_view set_node(db::txn &txn, const mutable_buffer &id, const json::object &node);
 
+	string_view set_node(db::txn &txn, const mutable_buffer &id, const json::object &node);
 	void get_node(const string_view &id, const node_closure &);
 
 	string_view get_head(const mutable_buffer &out, const id::room &);
@@ -54,8 +56,11 @@ namespace ircd::m::state
 	string_view insert(db::txn &, const mutable_buffer &head, const id::room &, const string_view &type, const string_view &state_key, const id::event &);
 	string_view insert(db::txn &, const mutable_buffer &head, const event &);
 
-	using search_closure = std::function<bool (const json::array &, const string_view &, const uint &, const uint &)>;
-	bool dfs(const string_view &node_id, const search_closure &);
+	bool dfs(const string_view &head, const search_closure &);
+	bool each(const string_view &head, const iter_bool_closure &);
+	bool each(const string_view &head, const string_view &type, const iter_bool_closure &);
+	size_t count(const string_view &head, const iter_bool_closure &);
+	size_t count(const string_view &head);
 
 	void get(const string_view &head, const json::array &key, const id_closure &);
 	void get(const string_view &head, const string_view &type, const string_view &state_key, const id_closure &);
diff --git a/ircd/m/state.cc b/ircd/m/state.cc
index 1eb2bc610..38d39b794 100644
--- a/ircd/m/state.cc
+++ b/ircd/m/state.cc
@@ -87,17 +87,69 @@ ircd::m::state::get(const string_view &head,
 	});
 }
 
+size_t
+ircd::m::state::count(const string_view &head)
+{
+	return count(head, []
+	(const json::array &key, const string_view &val)
+	{
+		return true;
+	});
+}
+
+size_t
+ircd::m::state::count(const string_view &head,
+                      const iter_bool_closure &closure)
+{
+	size_t ret{0};
+	each(head, [&ret, &closure]
+	(const json::array &key, const string_view &val)
+	{
+		ret += closure(key, val);
+		return true;
+	});
+
+	return ret;
+}
+
+///TODO: optimize
+bool
+ircd::m::state::each(const string_view &head,
+                     const string_view &type,
+                     const iter_bool_closure &closure)
+{
+	return each(head, [&type, &closure]
+	(const json::array &key, const string_view &val)
+	{
+		if(unquote(key.at(0)) != type)
+			return true;
+
+		return closure(key, val);
+	});
+}
+
+bool
+ircd::m::state::each(const string_view &head,
+                     const iter_bool_closure &closure)
+{
+	return dfs(head, [&closure]
+	(const json::array &key, const string_view &val, const uint &, const uint &)
+	{
+		return closure(key, val);
+	});
+}
+
 namespace ircd::m::state
 {
 	bool _dfs_recurse(const search_closure &, const node &, int &);
 }
 
 bool
-ircd::m::state::dfs(const string_view &node_id,
+ircd::m::state::dfs(const string_view &head,
                     const search_closure &closure)
 {
-	bool ret{false};
-	get_node(node_id, [&closure, &ret]
+	bool ret{true};
+	get_node(head, [&closure, &ret]
 	(const auto &node)
 	{
 		int depth(-1);
@@ -128,27 +180,27 @@ ircd::m::state::_dfs_recurse(const search_closure &closure,
 
 		if(!empty(child))
 		{
-			bool ret{false};
+			bool ret{true};
 			get_node(child, [&closure, &depth, &ret]
 			(const auto &node)
 			{
 				ret = _dfs_recurse(closure, node, depth);
 			});
 
-			if(ret)
-				return true;
+			if(!ret)
+				return ret;
 		}
 
 		if(rep.kn > pos)
 		{
 			const auto &key{rep.keys[pos]};
 			const auto &val{unquote(rep.vals[pos])};
-			if(closure(key, val, depth, pos))
-				return true;
+			if(!closure(key, val, depth, pos))
+				return false;
 		}
 	}
 
-	return false;
+	return true;
 }
 
 // Internal insertion operations