Search in background in the markdown IV window

Telegram/SourceFiles/iv/markdown/iv_markdown_controller.cpp

@@ -1069,25 +1069,26 @@ void Controller::hideSearchBar() {
 		SetMarkdownPreviewSearchMatches(_preview.get(), {}, -1);
 		_preview->setFocus();
 	}
+	invalidateSearchSession();
 	_searchEntries.clear();
 	_searchCurrentEntry = -1;
 }
 
-auto Controller::collectSearchEntries() const
--> std::vector<SearchEntry> {
+std::vector<Controller::SearchEntry> Controller::ScanSearchEntries(
+		const SearchSources &sources,
+		const QString &query) {
 	auto result = std::vector<SearchEntry>();
-	if (_searchQuery.isEmpty() || !_preview) {
+	if (query.isEmpty()) {
 		return result;
 	}
-	const auto sources = MarkdownPreviewSearchSources(_preview.get());
 	const auto scan = [&](const QString &text, auto &&push) {
 		auto from = 0;
 		while ((from = int(text.indexOf(
-				_searchQuery,
+				query,
 				from,
 				Qt::CaseInsensitive))) >= 0) {
-			push(from, from + int(_searchQuery.size()));
-			from += int(_searchQuery.size());
+			push(from, from + int(query.size()));
+			from += int(query.size());
 		}
 	};
 	for (auto i = 0; i != int(sources.size()); ++i) {
@@ -1106,6 +1107,31 @@ auto Controller::collectSearchEntries() const
 	return result;
 }
 
+void Controller::ensureSearchSnapshot() {
+	if (_searchSnapshot || !_preview) {
+		return;
+	}
+	_searchSnapshot = std::make_shared<const SearchSources>(
+		MarkdownPreviewSearchSources(_preview.get()));
+}
+
+void Controller::invalidateSearchSession() {
+	_searchSnapshot = nullptr;
+	_searchCache.clear();
+	++_searchGeneration;
+}
+
+std::vector<Controller::SearchEntry> Controller::rescanSearchEntries() {
+	invalidateSearchSession();
+	ensureSearchSnapshot();
+	if (!_searchSnapshot || _searchQuery.isEmpty()) {
+		return {};
+	}
+	auto result = ScanSearchEntries(*_searchSnapshot, _searchQuery);
+	_searchCache.emplace(_searchQuery, result);
+	return result;
+}
+
 void Controller::applySearchQuery(const QString &query) {
 	_searchQuery = query;
 	if (!_searchBar) {
@@ -1115,13 +1141,40 @@ void Controller::applySearchQuery(const QString &query) {
 }
 
 void Controller::refreshSearchResults() {
+	invalidateSearchSession();
 	if (_searchBar && _searchBar->shown()) {
 		rebuildSearchResults(_searchCurrentEntry, false);
 	}
 }
 
 void Controller::rebuildSearchResults(int preferredCurrent, bool activate) {
-	_searchEntries = collectSearchEntries();
+	_searchDesiredCurrent = preferredCurrent;
+	_searchDesiredActivate = activate;
+	if (_searchQuery.isEmpty() || !_preview) {
+		applySearchEntries({}, preferredCurrent, activate);
+		return;
+	}
+	const auto i = _searchCache.find(_searchQuery);
+	if (i != end(_searchCache)) {
+		DEBUG_LOG(("Native Markdown IV: search cache hit: %1"
+			).arg(_searchQuery));
+		auto entries = i->second;
+		applySearchEntries(std::move(entries), preferredCurrent, activate);
+		return;
+	}
+	if (_searchScanInFlight) {
+		DEBUG_LOG(("Native Markdown IV: search coalesced: %1"
+			).arg(_searchQuery));
+		return;
+	}
+	startSearchScan();
+}
+
+void Controller::applySearchEntries(
+		std::vector<SearchEntry> &&entries,
+		int preferredCurrent,
+		bool activate) {
+	_searchEntries = std::move(entries);
 	const auto total = int(_searchEntries.size());
 	_searchCurrentEntry = total
 		? std::clamp(preferredCurrent, 0, total - 1)
@@ -1129,6 +1182,72 @@ void Controller::rebuildSearchResults(int preferredCurrent, bool activate) {
 	applyCurrentSearchEntry(activate);
 }
 
+void Controller::startSearchScan() {
+	Expects(!_searchScanInFlight);
+
+	ensureSearchSnapshot();
+	if (!_searchSnapshot) {
+		return;
+	}
+	_searchScanInFlight = true;
+	DEBUG_LOG(("Native Markdown IV: search request: %1"
+		).arg(_searchQuery));
+	const auto weak = base::make_weak(this);
+	crl::async([
+		weak,
+		query = _searchQuery,
+		generation = _searchGeneration,
+		snapshot = _searchSnapshot
+	] {
+		if (!weak) {
+			return;
+		}
+		auto entries = ScanSearchEntries(*snapshot, query);
+		crl::on_main([
+			weak,
+			query,
+			generation,
+			entries = std::move(entries)
+		]() mutable {
+			if (const auto strong = weak.get()) {
+				strong->finishSearchScan(
+					query,
+					generation,
+					std::move(entries));
+			}
+		});
+	});
+}
+
+void Controller::finishSearchScan(
+		const QString &query,
+		int generation,
+		std::vector<SearchEntry> &&entries) {
+	_searchScanInFlight = false;
+	if (generation != _searchGeneration) {
+		DEBUG_LOG(("Native Markdown IV: search response dropped: %1"
+			).arg(query));
+	} else {
+		DEBUG_LOG(("Native Markdown IV: search response: %1 (%2 matches)"
+			).arg(query
+			).arg(int(entries.size())));
+		_searchCache[query] = entries;
+	}
+	if (!_searchBar || !_searchBar->shown() || _searchQuery.isEmpty()) {
+		return;
+	}
+	if (generation == _searchGeneration && query == _searchQuery) {
+		applySearchEntries(
+			std::move(entries),
+			_searchDesiredCurrent,
+			_searchDesiredActivate);
+	} else {
+		rebuildSearchResults(
+			_searchDesiredCurrent,
+			_searchDesiredActivate);
+	}
+}
+
 void Controller::resolveCurrentSearchEntry() {
 	if (!_preview) {
 		return;
@@ -1156,7 +1275,7 @@ void Controller::resolveCurrentSearchEntry() {
 		if (!ExpandMarkdownPreviewDetails(_preview.get(), anchorId)) {
 			return;
 		}
-		_searchEntries = collectSearchEntries();
+		_searchEntries = rescanSearchEntries();
 		const auto newTotal = int(_searchEntries.size());
 		const auto materialized = newTotal
 			- (oldTotal - (runEnd - runStart));

Telegram/SourceFiles/iv/markdown/iv_markdown_controller.h

@@ -7,8 +7,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "base/flat_map.h"
 #include "base/object_ptr.h"
 #include "base/unique_qptr.h"
+#include "base/weak_ptr.h"
 #include "iv/markdown/iv_markdown_document.h"
 #include "iv/markdown/iv_markdown_prepare.h"
 #include "ui/effects/animations.h"
@@ -35,7 +37,9 @@ class SearchBar;
 
 namespace Iv::Markdown {
 
-class Controller final {
+struct MarkdownArticleSearchSource;
+
+class Controller final : public base::has_weak_ptr {
 public:
 	Controller(
 		not_null<Delegate*> delegate,
@@ -75,6 +79,8 @@ private:
 	struct HistoryEntry;
 	struct SearchEntry;
 
+	using SearchSources = std::vector<MarkdownArticleSearchSource>;
+
 	void close();
 	void createWindow();
 	void createLayerManager();
@@ -99,7 +105,21 @@ private:
 	void resolveCurrentSearchEntry();
 	void applyCurrentSearchEntry(bool activate);
 	void stepSearchResult(int delta);
-	[[nodiscard]] std::vector<SearchEntry> collectSearchEntries() const;
+	[[nodiscard]] static std::vector<SearchEntry> ScanSearchEntries(
+		const SearchSources &sources,
+		const QString &query);
+	void ensureSearchSnapshot();
+	void invalidateSearchSession();
+	[[nodiscard]] std::vector<SearchEntry> rescanSearchEntries();
+	void applySearchEntries(
+		std::vector<SearchEntry> &&entries,
+		int preferredCurrent,
+		bool activate);
+	void startSearchScan();
+	void finishSearchScan(
+		const QString &query,
+		int generation,
+		std::vector<SearchEntry> &&entries);
 	void openSource();
 	[[nodiscard]] ViewerKind viewerKind() const;
 	[[nodiscard]] QString subtitleText() const;
@@ -180,6 +200,12 @@ private:
 	QString _searchQuery;
 	std::vector<SearchEntry> _searchEntries;
 	int _searchCurrentEntry = -1;
+	std::shared_ptr<const SearchSources> _searchSnapshot;
+	base::flat_map<QString, std::vector<SearchEntry>> _searchCache;
+	int _searchGeneration = 0;
+	int _searchDesiredCurrent = 0;
+	bool _searchDesiredActivate = false;
+	bool _searchScanInFlight = false;
 	std::vector<HistoryEntry> _history;
 	int _historyIndex = -1;
 	int _shownHistoryIndex = -1;