mu: refactor labels code

Split labels-cache and store-labels.

lib/mu-store-labels.hh

@@ -17,160 +17,16 @@
 **
 */
 
-#ifndef MU_LABELS_CACHE_HH
-#define MU_LABELS_CACHE_HH
-
-#include <set>
 #include <string>
-#include <unordered_map>
+#include "mu-option.hh"
+#include "mu-result.hh"
 
-#include "utils/mu-utils.hh"
-#include "utils/mu-option.hh"
-#include "message/mu-labels.hh"
+#ifndef MU_STORE_LABELS_HH
+#define MU_STORE_LABELS_HH
 
 namespace Mu {
 
-class Store;
-
-/**
- * The cache keeps track of what labels are being used. This can be used
- * for completion etc. and `mu label list`
- */
-class LabelsCache {
-public:
-	// maps a label to a number of occurrences
-	using Map = std::unordered_map<std::string, size_t>;
-	/**
-	 * CTOR
-	 *
-	 * Deserialize the map from a string
-	 *
-	 * @param serialized serialization string
-	 */
-	LabelsCache(const std::string serialized = {}): label_map_{deserialize(serialized)} {
-	}
-
-	/**
-	 * Add a label occurrence to the cache
-	 *
-	 * @param label some label
-	 */
-	void increase(const std::string& label) {
-		if (auto it = label_map_.find(label); it == label_map_.end())
-			label_map_.insert({label, 1});
-		else
-			++it->second;
-		dirty_ = true;
-	}
-	/**
-	 * Remove a label occurrence from the cache
-	 *
-	 * Removes the label completely if this was the _last_ occurence.
-	 *
-	 * @param label some label
-	 */
-	void decrease(const std::string& label) {
-		if (auto it = label_map_.find(label); it != label_map_.end()) {
-			if (it->second == 1)
-				label_map_.erase(it);
-			else
-				--it->second;
-			dirty_ = true;
-		}
-	}
-
-	/**
-	 * Update the cache with the label changes
-	 *
-	 * @param updates a vector of delta-labels
-	 */
-	void update(const Labels::DeltaLabelVec& updates) {
-		for(const auto& [delta, label]: updates) {
-			switch(delta) {
-			case Labels::Delta::Add:
-				increase(label);
-				break;
-			case Labels::Delta::Remove:
-				decrease(label);
-				break;
-			}
-		}
-	}
-
-	/**
-	 * Return a copy of the label-map
-	 *
-	 * @return the label-map
-	 */
-	Map label_map() const { return label_map_; }
-
-	// serialization/deserialization could be optimized, but is not super
-	// time-critical
-
-	/**
-	 * Serialize the cache into a string.
-	 *
-	 * Note: this also marks the cache a _non_ dirty;
-	 *
-	 * @return serialized cache
-	 */
-	[[nodiscard]] std::string serialize() const {
-		std::string s;
-		for (const auto&[label, n]: label_map_)
-			s += mu_format("{}{}{}\n", label, SepaChar2, n);
-		dirty_ = false;
-		return s;
-	}
-
-	/**
-	 * Deserialize the cache into a Map
-	 *
-	 * @return serialized cache
-	 */
-	Map deserialize(const std::string& serialized) const {
-
-		Map       map;
-		std::stringstream ss{serialized, std::ios_base::in};
-		std::string       line;
-
-		while (std::getline(ss, line)) {
-			if (const auto parts =
-			    Mu::split(line, SepaChar2); parts.size() != 2)
-				mu_warning("error: '{}'", line);
-			else
-				map.emplace(std::move(parts[0]),
-					    static_cast<std::size_t>(
-						    g_ascii_strtoll(parts[1].c_str(),{}, 10)));
-		}
-		return map;
-	}
-
-
-	/**
-	 * Restore the labels-cache from the labels seen in the store.
-	 *
-	 * @param store a store
-	 *
-	 * @return Ok() or some error
-	 */
-	Result<void> restore(const Store& store);
-
-
-	/**
-	 * Is the cache "dirty"?
-	 *
-	 * I.e. have there been changes since "serialize()" was called?
-	 *
-	 * @return true or false
-	 */
-	bool dirty() const {
-		return dirty_;
-	}
-
-private:
-	Map label_map_;
-	mutable bool dirty_{};
-};
+class Store; // fwd declaration
 
 /**
  * Export labels to a file
@@ -187,7 +43,6 @@ private:
 Result<std::string> export_labels(const Store& store,
 				  const std::string& query="",
 				  Option<std::string> path={});
-
 /**
  * Import labels from a file
  *
@@ -203,6 +58,7 @@ Result<std::string> export_labels(const Store& store,
  */
 Result<void> import_labels(Store&, const std::string& path, bool dry_run,
 			   bool quiet, bool verbose);
+} // Mu
 
-} // namespace Mux
-#endif /*MU_LABELS_CACHE_HH*/
+
+#endif /*MU_STORE_LABELS_HH*/