Closes #14

core/decode_database.cpp

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2026 Dim Himro
+
+#include "decode_database.h"
+#include <stdexcept>
+#include <unordered_set>
+#include <utility>
+
+DecodeDatabase::Storage::Storage(std::vector<DecodeFrame> definitions)
+    : frames(std::move(definitions)) {
+    frameIndexByKey.reserve(frames.size());
+    for (std::size_t index = 0U; index < frames.size(); ++index) {
+        const DecodeFrame &frame = frames[index];
+        if (!frameIndexByKey.emplace(frame.GetKey(), index).second)
+            throw std::invalid_argument("Duplicate runtime frame key");
+        std::unordered_set<std::string> names;
+        for (const DecodeSignal &signal: frame.signals) {
+            if (!names.insert(signal.name).second)
+                throw std::invalid_argument("Duplicate runtime signal key");
+        }
+    }
+}
+
+DecodeDatabase::DecodeDatabase(std::vector<DecodeFrame> frames)
+    : storage(std::make_shared<const Storage>(std::move(frames))) {
+}
+
+const std::vector<DecodeFrame> &DecodeDatabase::GetFrames() const {
+    static const std::vector<DecodeFrame> empty;
+    return storage ? storage->frames : empty;
+}
+
+std::shared_ptr<const DecodeFrame> DecodeDatabase::FindFrame(const FrameKey &key) const {
+    if (!storage)
+        return nullptr;
+    const std::unordered_map<FrameKey, std::size_t, FrameKeyHasher>::const_iterator it =
+            storage->frameIndexByKey.find(key);
+    if (it == storage->frameIndexByKey.end())
+        return nullptr;
+    return std::shared_ptr<const DecodeFrame>(storage, &storage->frames[it->second]);
+}
+
+std::shared_ptr<const DecodeSignal> DecodeDatabase::FindSignal(const SignalKey &key) const {
+    const std::shared_ptr<const DecodeFrame> frame = FindFrame(key.frame);
+    if (!frame)
+        return nullptr;
+    for (const DecodeSignal &signal: frame->signals) {
+        if (signal.name == key.name)
+            return std::shared_ptr<const DecodeSignal>(frame, &signal);
+    }
+    return nullptr;
+}