[Project] Css: Add preliminary stylesheet support

1 files changed, 67 insertions, 9 deletions

diff --git a/src/libserver/css/css.cxx b/src/libserver/css/css.cxx
index 4587085a8..bd26cee1e 100644
--- a/src/libserver/css/css.cxx
+++ b/src/libserver/css/css.cxx
@@ -16,7 +16,7 @@
 
 #include "css.h"
 #include "css.hxx"
-#include "css_style.hxx"
+#include "contrib/robin-hood/robin_hood.h"
 #include "css_parser.hxx"
 #define DOCTEST_CONFIG_IMPLEMENTATION_IN_DLL
 #define DOCTEST_CONFIG_IMPLEMENT
@@ -28,8 +28,6 @@ rspamd_css_parse_style (rspamd_mempool_t *pool, const guchar *begin, gsize len,
 {
 	auto parse_res = rspamd::css::parse_css(pool, {(const char* )begin, len});
 
-#if 0
-	/* Return once semantical parsing is done */
 	if (parse_res.has_value()) {
 		return reinterpret_cast<rspamd_css>(parse_res.value().release());
 	}
@@ -39,9 +37,6 @@ rspamd_css_parse_style (rspamd_mempool_t *pool, const guchar *begin, gsize len,
 				"parse error");
 		return nullptr;
 	}
-#else
-	return nullptr;
-#endif
 }
 
 namespace rspamd::css {
@@ -49,10 +44,73 @@ namespace rspamd::css {
 INIT_LOG_MODULE_PUBLIC(css);
 
 class css_style_sheet::impl {
-
+public:
+	using selector_ptr = std::unique_ptr<css_selector>;
+	using selectors_hash = robin_hood::unordered_flat_map<selector_ptr, css_declarations_block_ptr>;
+	using universal_selector_t = std::pair<selector_ptr, css_declarations_block_ptr>;
+	selectors_hash tags_selector;
+	selectors_hash class_selectors;
+	selectors_hash id_selectors;
+	std::optional<universal_selector_t> universal_selector;
 };
 
-css_style_sheet::css_style_sheet () : pimpl(new impl) {}
-css_style_sheet::~css_style_sheet () {}
+css_style_sheet::css_style_sheet(rspamd_mempool_t *pool)
+		:  pool(pool), pimpl(new impl) {}
+css_style_sheet::~css_style_sheet() {}
+
+auto
+css_style_sheet::add_selector_rule(std::unique_ptr<css_selector> &&selector,
+									css_declarations_block_ptr decls) -> void
+{
+	impl::selectors_hash *target_hash = nullptr;
+
+	switch(selector->type) {
+	case css_selector::selector_type::SELECTOR_ALL:
+		if (pimpl->universal_selector) {
+			/* Another universal selector */
+			msg_debug_css("redefined universal selector, merging rules");
+			pimpl->universal_selector->second->merge_block(*decls);
+		}
+		else {
+			msg_debug_css("added universal selector");
+			pimpl->universal_selector = std::make_pair(std::move(selector),
+					decls);
+		}
+		break;
+	case css_selector::selector_type::SELECTOR_CLASS:
+		target_hash = &pimpl->class_selectors;
+		break;
+	case css_selector::selector_type::SELECTOR_ID:
+		target_hash = &pimpl->id_selectors;
+		break;
+	case css_selector::selector_type::SELECTOR_ELEMENT:
+		target_hash = &pimpl->tags_selector;
+		break;
+	}
+
+	if (target_hash) {
+		auto found_it = target_hash->find(selector);
+
+		if (found_it == target_hash->end()) {
+			/* Easy case, new element */
+			target_hash->insert({std::move(selector), decls});
+		}
+		else {
+			/* The problem with merging is actually in how to handle selectors chains
+			 * For example, we have 2 selectors:
+			 * 1. class id tag -> meaning that we first match class, then we ensure that
+			 * id is also the same and finally we check the tag
+			 * 2. tag class id -> it means that we check first tag, then class and then id
+			 * So we have somehow equal path in the xpath terms.
+			 * I suppose now, that we merely check parent stuff and handle duplicates
+			 * merging when finally resolving paths.
+			 */
+			auto sel_str = selector->to_string().value_or("unknown");
+			msg_debug_css("found duplicate selector: %*s", (int)sel_str.size(),
+					sel_str.data());
+			found_it->second->merge_block(*decls);
+		}
+	}
+}
 
 }
\ No newline at end of file