feat: add VariableContext

Author: marklawlor

cpp/VariableContext.cpp

@@ -0,0 +1,82 @@
+#include "VariableContext.hpp"
+
+namespace margelo::nitro::cssnitro {
+
+    // Initialize the static contexts map
+    std::unordered_map<std::string, std::unordered_map<std::string, std::shared_ptr<reactnativecss::Observable<AnyValue>>>> VariableContext::contexts;
+
+    void VariableContext::createContext(const std::string &key) {
+        // Create a new empty map for this context
+        contexts[key] = std::unordered_map<std::string, std::shared_ptr<reactnativecss::Observable<AnyValue>>>();
+    }
+
+    void VariableContext::deleteContext(const std::string &key) {
+        // Remove the context from the map
+        contexts.erase(key);
+    }
+
+    const AnyValue &VariableContext::getVariable(const std::string &key, const std::string &name,
+                                                 reactnativecss::Effect::GetProxy &get) {
+        // Find the context
+        auto contextIt = contexts.find(key);
+        if (contextIt == contexts.end()) {
+            // Context doesn't exist, throw or return a default value
+            static AnyValue defaultValue;
+            return defaultValue;
+        }
+
+        // Find the variable in the context
+        auto &variableMap = contextIt->second;
+        auto varIt = variableMap.find(name);
+        if (varIt == variableMap.end()) {
+            // Variable doesn't exist, return a default value
+            static AnyValue defaultValue;
+            return defaultValue;
+        }
+
+        // Get the observable and subscribe the effect to it
+        auto &observable = varIt->second;
+        return get(*observable);
+    }
+
+    void VariableContext::setVariable(const std::string &key, const std::string &name,
+                                      const AnyValue &value) {
+        // Find or create the context
+        auto contextIt = contexts.find(key);
+        if (contextIt == contexts.end()) {
+            // Context doesn't exist, create it
+            createContext(key);
+            contextIt = contexts.find(key);
+        }
+
+        auto &variableMap = contextIt->second;
+
+        // Find or create the observable for this variable
+        auto varIt = variableMap.find(name);
+        if (varIt == variableMap.end()) {
+            // Variable doesn't exist, create a new Observable with the value
+            auto observable = reactnativecss::Observable<AnyValue>::create(value);
+            variableMap[name] = observable;
+        } else {
+            // Variable exists, update its value
+            varIt->second->set(value);
+        }
+    }
+
+    void VariableContext::setVariable(const std::string &key, const std::string &name,
+                                      std::shared_ptr<reactnativecss::Observable<AnyValue>> observable) {
+        // Find or create the context
+        auto contextIt = contexts.find(key);
+        if (contextIt == contexts.end()) {
+            // Context doesn't exist, create it
+            createContext(key);
+            contextIt = contexts.find(key);
+        }
+
+        auto &variableMap = contextIt->second;
+
+        // Set the variable to use the provided Observable directly
+        variableMap[name] = observable;
+    }
+
+} // namespace margelo::nitro::cssnitro

cpp/VariableContext.hpp

@@ -0,0 +1,41 @@
+#pragma once
+
+#include <string>
+#include <unordered_map>
+#include <memory>
+#include <NitroModules/AnyValue.hpp>
+#include "Observable.hpp"
+#include "Effect.hpp"
+
+namespace margelo::nitro::cssnitro {
+
+    using AnyValue = ::margelo::nitro::AnyValue;
+
+    class VariableContext {
+    public:
+        // Static map: context key -> (variable name -> Observable<AnyValue>)
+        static std::unordered_map<std::string, std::unordered_map<std::string, std::shared_ptr<reactnativecss::Observable<AnyValue>>>> contexts;
+
+        // Create a new context with the given key
+        static void createContext(const std::string &key);
+
+        // Delete a context by key
+        static void deleteContext(const std::string &key);
+
+        // Get a variable from a context, subscribing the effect to changes
+        static const AnyValue &getVariable(const std::string &key, const std::string &name,
+                                           reactnativecss::Effect::GetProxy &get);
+
+        // Set a variable in a context
+        static void
+        setVariable(const std::string &key, const std::string &name, const AnyValue &value);
+
+        // Set a variable in a context using an existing Observable
+        static void setVariable(const std::string &key, const std::string &name,
+                                std::shared_ptr<reactnativecss::Observable<AnyValue>> observable);
+
+    private:
+        VariableContext() = delete; // Static-only class
+    };
+
+} // namespace margelo::nitro::cssnitro