initial

modules/network/include/metrics/HistoryBuffer.hpp

@@ -0,0 +1,80 @@
+
+#pragma once
+
+#include "common.hpp"
+
+#include <optional>
+#include <string>
+#include <vector>
+
+/**
+ * Stores history of a property for data analysis
+ */
+template<typename TKey, typename TValue>
+class HistoryBuffer {
+private:
+    size_t m_head, m_tail;
+    std::vector<std::pair<TKey, TValue>> m_buffer;
+
+public:
+    size_t size() const {
+        if(m_tail > m_head) {
+            return max_size() - m_tail + m_head;
+        }
+
+        return (m_head - m_tail) % max_size();
+    }
+
+    size_t max_size() const { return m_buffer.size(); }
+
+    bool is_full(float percentage) {
+        return size() / (float)max_size() > percentage;
+    }
+
+    void clear() {
+        m_tail = m_head = 0;
+    }
+
+    GET_REF(m_buffer, buffer);
+
+    HistoryBuffer(TKey default_key, TValue&& default_value, size_t size) :
+        m_head(0), m_tail(0), m_buffer(size) {
+    }
+
+    std::optional<const TValue*> get(TKey key) const {
+        for(size_t i = m_tail; i != m_head; (i++) % max_size()) {
+            if(m_buffer[i].first > key) {
+                return {};
+            }
+
+            if(m_buffer[i].first == key) {
+                return &m_buffer[i].second;
+            }
+        }
+
+        return {};
+    }
+
+    bool set(TKey key, const TValue& value) {
+        if(key < m_buffer.at(m_tail).first) {
+            return false;
+        }
+
+        int i = m_tail + 1;
+        if(m_tail != m_head) {
+            for(i = m_tail + 1; i != m_head; i++) {
+                if(m_buffer.at(i).first > key) {
+                    m_buffer[(i - 1) % max_size()] = std::make_pair(key, value);
+                    m_head++;
+                    return true;
+                } else {
+                    m_buffer[(i - 1) % max_size()] = m_buffer[i];
+                }
+            }
+        }
+
+        m_buffer[(i - 1) % max_size()] = std::make_pair(key, value);
+        m_head = (m_head + 1) % max_size();
+        return true;
+    }
+};