refactor message contexts

src/fragment_store/internal_mfs_contexts.cpp

@@ -0,0 +1,149 @@
+#include "./internal_mfs_contexts.hpp"
+
+#include "./message_fragment_store.hpp"
+
+#include <solanaceae/contact/components.hpp>
+#include <solanaceae/message3/components.hpp>
+#include <solanaceae/message3/contact_components.hpp>
+
+#include <iostream>
+
+static bool isLess(const std::vector<uint8_t>& lhs, const std::vector<uint8_t>& rhs) {
+	size_t i = 0;
+	for (; i < lhs.size() && i < rhs.size(); i++) {
+		if (lhs[i] < rhs[i]) {
+			return true;
+		} else if (lhs[i] > rhs[i]) {
+			return false;
+		}
+		// else continue
+	}
+
+	// here we have equality of common lenths
+
+	// we define smaller arrays to be less
+	return lhs.size() < rhs.size();
+}
+
+bool Message::Contexts::ContactFragments::insert(ObjectHandle frag) {
+	if (frags.contains(frag)) {
+		return false;
+	}
+
+	// both sorted arrays are sorted ascending
+	// so for insertion we search for the last index that is <= and insert after it
+	// or we search for the first > (or end) and insert before it    <---
+	// since equal fragments are UB, we can assume they are only > or <
+
+	size_t begin_index {0};
+	{ // begin
+		const auto pos = std::find_if(
+			sorted_begin.cbegin(),
+			sorted_begin.cend(),
+			[frag](const Object a) -> bool {
+				const auto begin_a = frag.registry()->get<ObjComp::MessagesTSRange>(a).begin;
+				const auto begin_frag = frag.get<ObjComp::MessagesTSRange>().begin;
+				if (begin_a > begin_frag) {
+					return true;
+				} else if (begin_a < begin_frag) {
+					return false;
+				} else {
+					// equal ts, we need to fall back to id (id can not be equal)
+					return isLess(frag.get<ObjComp::ID>().v, frag.registry()->get<ObjComp::ID>(a).v);
+				}
+			}
+		);
+
+		begin_index = std::distance(sorted_begin.cbegin(), pos);
+
+		// we need to insert before pos (end is valid here)
+		sorted_begin.insert(pos, frag);
+	}
+
+	size_t end_index {0};
+	{ // end
+		const auto pos = std::find_if_not(
+			sorted_end.cbegin(),
+			sorted_end.cend(),
+			[frag](const Object a) -> bool {
+				const auto end_a = frag.registry()->get<ObjComp::MessagesTSRange>(a).end;
+				const auto end_frag = frag.get<ObjComp::MessagesTSRange>().end;
+				if (end_a > end_frag) {
+					return true;
+				} else if (end_a < end_frag) {
+					return false;
+				} else {
+					// equal ts, we need to fall back to id (id can not be equal)
+					return isLess(frag.get<ObjComp::ID>().v, frag.registry()->get<ObjComp::ID>(a).v);
+				}
+			}
+		);
+
+		end_index = std::distance(sorted_end.cbegin(), pos);
+
+		// we need to insert before pos (end is valid here)
+		sorted_end.insert(pos, frag);
+	}
+
+	frags.emplace(frag, InternalEntry{begin_index, end_index});
+
+	// now adjust all indicies of fragments coming after the insert position
+	for (size_t i = begin_index + 1; i < sorted_begin.size(); i++) {
+		frags.at(sorted_begin[i]).i_b = i;
+	}
+	for (size_t i = end_index + 1; i < sorted_end.size(); i++) {
+		frags.at(sorted_end[i]).i_e = i;
+	}
+
+	return true;
+}
+
+bool Message::Contexts::ContactFragments::erase(Object frag) {
+	auto frags_it = frags.find(frag);
+	if (frags_it == frags.end()) {
+		return false;
+	}
+
+	assert(sorted_begin.size() == sorted_end.size());
+	assert(sorted_begin.size() > frags_it->second.i_b);
+
+	sorted_begin.erase(sorted_begin.begin() + frags_it->second.i_b);
+	sorted_end.erase(sorted_end.begin() + frags_it->second.i_e);
+
+	frags.erase(frags_it);
+
+	return true;
+}
+
+Object Message::Contexts::ContactFragments::prev(Object frag) const {
+	// uses range begin to go back in time
+
+	auto it = frags.find(frag);
+	if (it == frags.end()) {
+		return entt::null;
+	}
+
+	const auto src_i = it->second.i_b;
+	if (src_i > 0) {
+		return sorted_begin[src_i-1];
+	}
+
+	return entt::null;
+}
+
+Object Message::Contexts::ContactFragments::next(Object frag) const {
+	// uses range end to go forward in time
+
+	auto it = frags.find(frag);
+	if (it == frags.end()) {
+		return entt::null;
+	}
+
+	const auto src_i = it->second.i_e;
+	if (src_i+1 < sorted_end.size()) {
+		return sorted_end[src_i+1];
+	}
+
+	return entt::null;
+}
+